JPS6112106B2 - - Google Patents

Description

Detailed Description of the Invention The present invention is a vaporizer that vaporizes and depressurizes a liquefied gas such as LPG and supplies it to an engine through a mixture. The operation of the secondary valve body that opens and closes the gas passage provided between the secondary chamber and the secondary chamber that sends the gas to the mixer is adjustable, so that the gas pressure in the secondary chamber can be changed as appropriate. .

The gas pressure in the secondary chamber of a vaporizer has a significant effect on the air-fuel mixture, and many vaporizers are equipped with means for appropriately adjusting the opening operation of the secondary valve. For example, Publication of Utility Model Publication No. 50-25848, Publication of Utility Model Publication No. 51-
As disclosed in Japanese Patent No. 114514, a spring is provided that acts in the opening direction in opposition to the spring that acts in the closing direction of the secondary valve, and the opening operation of the secondary valve is adjusted by adjusting this spring force from the outside. There is one that adjusts the However, these only make it easier to open the secondary valve by compressing the spring and limiting its extension, so although the rich side of the air-fuel mixture can be properly adjusted, the lean side cannot be adjusted. Moreover, since the adjustment is done manually, it is impossible to automatically adjust the air-fuel mixture according to the situation while the engine is running to obtain a proper air-fuel mixture. In addition, Japanese Patent Publication No. 39-26224 discloses a technology that automatically adjusts the opening operation of the secondary valve using the engine's suction negative pressure, but the opening of the secondary valve is increased only under full load. Therefore, it cannot respond to various driving situations.

The present invention is intended to solve these problems, and embodiments thereof will be described below.

The drawing shows an example of a vaporizer equipped with a secondary chamber gas pressure adjustment mechanism according to the present invention, and a gas inlet 1 connected to a pressure-resistant container (not shown) faces the inside of a primary chamber 2 to form a primary valve port 3. The primary valve port 3 is opened and closed by the primary valve body 7 at the tip of the lever 6 whose base end is engaged with the hook piece 5 built in the primary chamber 2 and fixed to the membrane 4, and the primary valve port 3 is opened and closed from the primary chamber 2. A gas passage 9 leading to the secondary chamber 8 faces the inside of the secondary chamber 8 to form a secondary valve port 10, and a membrane 11 built in the secondary chamber 8 is formed.
The secondary valve body 1 at the tip of the lever 12 whose base end is engaged with the
3 opens and closes the secondary valve port 10, thereby adjusting the gas pressure and sending the gas through the gas delivery port 14 to a mixer (not shown).

An adjustable spring 16 is built into the primary operation chamber 15, which is separated from the primary chamber 2 by the membrane 4 and into which the atmosphere is introduced.
The membrane 4 moves toward the primary operation chamber 15 against the force, and the lever 6 is rotated counterclockwise in the figure around the support shaft 17 to bring the primary valve body 7 into close contact with the primary valve port 3, and the gas is turned off. The inlet 1 is closed, but when the gas pressure decreases, the membrane 4 moves toward the primary chamber 2 by the force of the spring 16.
Turn the lever 6 in the opposite direction to open the gas inlet 1.

A lever 12 having a secondary valve body 13 is rotatably supported on a support shaft 18 and is actuated by a spring 19 that acts in the direction of closing the gas passage 9. It is loosely fitted onto the fixed pin 20 and is further brought into contact engagement with a nut-shaped contact piece 22 fixedly protruding from the center of the negative pressure operating membrane 21 . The secondary operation chamber 23, which is separated from the secondary chamber 8 by a negative pressure operating membrane 21, introduces engine suction negative pressure and has a built-in spring 24. When the engine is stopped, two springs 19, The force of 24 is used to bring the secondary valve body 13 into close contact with the secondary valve port 10 and close the gas passage 9. However, when the engine is operated and suction negative pressure is generated, the negative pressure actuating membrane 21 resists the force of the spring 24. The contact piece 22 moves towards the secondary operation chamber 23 and the lever 1
2, and the lever 12 is made rotatable.

The part separated by the secondary chamber 8 and the membrane 11 forms an atmospheric chamber 25, and when the gas pressure in the secondary chamber 8 becomes lower than atmospheric pressure, the membrane 11 moves into the secondary chamber 8 due to the pressure difference. The lever 12 is rotated clockwise in the figure against the force of the spring 19 to open the gas passage 9, and the gas pressure is increased by the spring 19 in the secondary chamber 8.
The pressure is reduced according to the force of the

A membrane 11 that rotates a lever 12 having a secondary valve body 13 has a spring 2 on the side opposite to the lever mounting position.
6, the tip of the balance lever 28 rotatably supported on the support shaft 27 receives this spring 26, and a weakening spring 29 acting in the direction of weakening the force of the spring 26 is placed on the opposite side of the support shaft 27. Further, a counter lever 31 rotatably supported on a support shaft 30 is brought into contact with the base end. The counter lever 31 has adjusting screws 32 and 33 screwed into the wall of the atmospheric pressure 25 and extending in a right angle direction, which act as two stoppers.
The tips of the two are in contact with each other. The first adjusting screw 32 limits the expansion range of the spring 26, and when the first adjusting screw 32 is screwed in and the counter lever 31 rotates the balance lever 28 clockwise in the figure, the spring 26 is compressed. In this state, when the engine starts and suction negative pressure is generated and the negative pressure operating membrane 21 is separated from the lever 12, the membrane 1 between the secondary chamber 8 and the atmospheric chamber 25
1 are two springs 19 and 26 that act on the lever 12.
Since the pressing forces of the secondary valve body 13 are balanced, the secondary valve body 13 is easily sucked and moved by the relatively low negative pressure in the secondary chamber 8, and the secondary valve body 13 is opened widely. Therefore, the fuel gas required during idling with a small air flow rate and light load low speed operation can be appropriately supplied. The second adjustment screw 33 limits the range of compression of the spring 26. When the second adjustment screw 33 is screwed in and the balance lever 28 is rotated counterclockwise in the figure, the spring 26 will expand and its force will be weakened, thereby reducing the air flow rate. The opening operation of the secondary valve body 13 is slowed down in an operating range where there is little. In the high-speed operation range, the membrane 1 is adjusted regardless of the two adjustment screws 32 and 33.
1 towards the secondary chamber 8 weakens the force of the spring 26, so that the membrane 11 is controlled only by the force of the spring 19 acting on the lever 12.

At the tip of the balance lever 28, on the side opposite to the support surface of the spring 26, the tip of a rod-shaped actuating piece 34 is opposed, and there is a membrane (the same can be used instead of a piston) that moves under the pressure of an operating pressure chamber 35. The actuating member 36 is formed with a spring 34 that protrudes from the actuating member 36, and a spring 37 that acts in the direction of pressing the actuating piece 34 against the balance lever 28 is housed in the operating pressure chamber 35. Either the engine suction negative pressure or the atmosphere is introduced into this operating pressure chamber 35 via an electromagnetic switching valve 38.

When suction negative pressure is introduced into the operating pressure chamber 35, the actuating member 36 moves toward the operating pressure chamber 35 against the force of the spring 37 and separates from the balance lever 28, so the spring 26 expands and the secondary valve body 13 It opens and closes as described above. When the suction negative pressure is low or atmospheric pressure is introduced into the operating pressure chamber 35, the force of the spring 37 causes the actuating member 36 to move toward the balance lever 28, pushing it and compressing the spring 26, so that the secondary valve is activated. The body 13 becomes easier to open or its degree of opening increases.

That is, the membrane 1 that controls the opening and closing operation of the secondary valve body 13
A spring 26 that acts in the opening direction of the secondary valve body 13 is applied to the spring 26, and the position of the rotatable balance lever 28, which supports this spring 26, is held by another weakening spring 29, so that the secondary valve When the body 13 opens the gas passage 9 and connects the primary chamber 2 and the secondary chamber 8, the spring 26 is applied to the secondary valve body 13 until it balances with the spring 19 acting on the lever 12 to which the secondary valve body 13 is attached. The applied load gradually increases in proportion to the head, and as a result, the engine speed changes in proportion to the opening of the mixer throttle valve, which not only improves the no-load characteristics but also during idling and light load low speed operation. This ensures that the fuel gas supply is appropriate.

According to the present invention, the actuating member 36 that responds to the pressure in the operating pressure chamber 35 that switches between suction negative pressure and atmospheric pressure is actuated on the balance lever 28, and when atmospheric pressure is introduced, the above-mentioned intake air amount is set. The opening degree of the secondary valve body 13 is increased by compressing the spring 26 which acts in the operating range where the negative pressure is low, and when the suction negative pressure is introduced, the secondary valve body 13 is
The spring 26 is kept in a certain degree of compression to make it easier to open, but when the negative pressure increases, the balance lever 28
The actuating member 36 is separated from the valve body 13 to allow the secondary valve body 13 to perform its normal operation. Therefore, when starting the engine,
If atmospheric pressure is introduced during idling and light-load, low-speed operation, the secondary valve body 13 will be wide open, and not only will it be possible to supply the required air-fuel mixture with a relatively high concentration to the engine regardless of the small amount of intake air, but also during acceleration. By introducing atmospheric pressure, a highly concentrated mixture can be supplied, and even when the engine is fully open and at low speed, the required mixture can be supplied by using the low suction negative pressure or by introducing atmospheric pressure, depending on the operating conditions. By appropriately switching between suction negative pressure and atmospheric pressure, the mixture ratio characteristics can be automatically changed and an appropriate mixture can be supplied to the engine.

Also according to the invention, two adjustment screws 32, 3
3, by limiting the movement of the balance lever 28 to an appropriate range, the range of compression and expansion of the spring 26 can be arbitrarily limited, and the opening degree of the secondary valve body 13 can be adjusted steplessly by adjusting screws 32 and 33. The gas pressure in the secondary chamber 8 can be set arbitrarily, and the optimum mixing ratio can be obtained by making fine adjustments according to the composition of the fuel gas in addition to the operating conditions. It is something.

[Brief explanation of the drawing]

The drawings are longitudinal sectional views showing embodiments of the present invention. 2...Primary chamber, 7...Primary valve body, 8...Secondary chamber, 9...Gas passage, 10...Secondary valve port, 11...
...Membrane, 12...Lever, 13...Secondary valve body, 23
... Secondary operation chamber, 26 ... Spring, 28 ... Balance lever, 29 ... Spring, 31 ... Counter lever, 32, 33 ... Adjustment screw, 34 ... Actuation piece, 35 ... Operation pressure chamber , 36... operating member, 3
7...Spring, 38...Switching valve.

Claims (1)

[Scope of Claims] 1. A primary chamber 2 that introduces liquefied gas, a secondary chamber 8 that sends out reduced pressure gas, a gas passage 9 that leads from the primary chamber 2 to the secondary chamber 8, and a and a lever 12 having a secondary valve element 13 attached to a membrane 11 operated by negative pressure to open and close the gas passage 9, so that the secondary valve element 13 can be opened when suction negative pressure is generated in the engine. This liquefied gas vaporizer includes a spring 26 that is provided on the opposite side of the membrane 11 from the mounting position of the lever 12 and acts in the opening direction of the secondary valve body 13, and a rotatable balance lever that supports this spring 26. 28 and this balance lever 28
a weakening spring 29 acting in a direction to weaken the force of the spring, an actuating member 36 disposed on the opposite side of the balance lever 28 from the supporting surface of the spring 26, and either the engine suction negative pressure or the atmospheric pressure. When negative suction pressure is introduced, the actuating member 36 moves away from the balance lever 28 to extend the spring 26, and when atmospheric pressure is introduced, the actuating member 36 pushes the balance lever 28 to release the spring. 26
A liquefied gas vaporizer characterized by being configured to compress liquefied gas. 2. Operates by the primary chamber 2 that introduces liquefied gas, the secondary chamber 8 that sends out the reduced pressure gas, the gas passage 9 that leads from the primary chamber 2 to the secondary chamber 8, and the negative pressure of the secondary chamber 8. and a lever 12 having a secondary valve element 13 attached to a membrane 11 that opens and closes the gas passage 9, and in which the secondary valve element 13 is in a state where it can be opened when negative suction pressure is generated in the engine. , a spring 26 that is provided on the opposite side of the membrane 11 to the mounting position of the lever 12 and acts in the opening direction of the secondary valve body 13, a rotatable balance lever 28 that supports this spring 26, and this balance lever. 28
a weakening spring 29 acting in a direction to weaken the force of the spring 26, and the spring 2 of the balance lever 28.
an actuating member 36 disposed opposite the support surface of 6;
When either the suction negative pressure or the atmospheric pressure of the engine is switched and the suction negative pressure is introduced, the actuating member 3
6 moves away from the balance lever 28 to extend the spring 26, but when atmospheric pressure is introduced, the operating pressure chamber 35 acts to push the balance lever 28 and compress the spring 26, and limits the movement of the balance lever 28. two adjustment screws 32, 3 which respectively limit the compression and extension ranges of the tie spring 26;
3. A liquefied gas vaporizer characterized by comprising: