JP2693711B2 - Cylinder head for internal combustion engine with air-assisted direct fuel injection system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to a cylinder head for an internal combustion engine having an air-assisted direct fuel injection device.

[0002]

BACKGROUND OF THE INVENTION Various methods are currently known for allowing air-assisted direct fuel injection into the cylinder head of an internal combustion engine. In some of these methods, high pressure air is created by a suitable device external to the engine, fuel is injected into a suitable chamber, and the mixture formed therein is then placed on the cylinder head of the engine. It is supplied into the combustion chamber by opening the opened valve.

Among these various known methods, different formats can be established. That is, one type has high pressure air, and therefore an electromechanical actuated small section valve,
The second type also has low pressure air and thus a large valve with all-mechanical actuation.

However, both of these major types have various drawbacks, especially in the case of small engines.

In practice, the first type is structurally complex because it must produce high pressure compressed air. Furthermore, since the moment of injection must be controlled in addition to the opening time,
The electronic valve control circuit becomes complicated.

The second type has a lubrication problem, and a compensating container must be provided to adjust the pressure difference between the crankcase and the injection valve. This entails an additional increase in cost and space.

The object of the present invention is mainly to solve the above-mentioned problems, for example by eliminating high-pressure air, facilitating lubrication and reducing the control and verification required for the above-mentioned known methods. is there.

This object is achieved according to the invention by the provision of a cylinder head characterized by the claims.

Non-limiting examples of cylinder heads having the structural and functional features and advantages of the present invention are shown in the accompanying drawings.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, this shows a cylinder 51 of an internal combustion engine having an associated crankcase 52 and an associated upper head 11. A cylinder head 11 having a combustion chamber 12 below extends upwards into a movable part 13 and is provided with an electromagnetic fuel injector, for example housed in a seat 14 and shown diagrammatically at 15.

A chamber 16 is provided inside the movable part 13 and the cylinder head 11. Further, in addition to the chamber 16, a portion 17 protruding from both the cylinder head 11 and the movable portion 13 is provided. The projecting portion 17 is provided with a shaft 18 rotatably supported by two bearings 19. Facing the chamber 16, a plate-like portion 20 is provided at a first end of a shaft 18, and the shaft is eccentrically pivotably mounted on the first end of a connecting rod 22 by means of a related pin 21. . The connecting rod, at the other end, is pivotally mounted at 54 to the injection piston 23, which injects the air-fuel mixture formed in the chamber 16 during its compression phase.

The injection piston 23 is housed in an extension or lower part 24 of the chamber 16, the wall of which is defined by a jacket 25 having an outwardly convex lateral part 26, which is used as a transfer duct. The piston slides inside.

A jacket 25 having a closure member 53 (FIG. 4) or an alternative member (FIGS. 5, 6 and 8) on the wall 27 at one end provides a suitable valve seat 28, or valve opening, a movable mushroom. A shaped valve is housed, and the mushroom shaped valve may close the lower opening of the valve seat 28. The valve seat 28 is communicated upwardly to the lower extension 24 of the chamber 16 by a series of holes 30. The mushroom valve 29 is a radial disc spring 58 fixed to the valve rod 32.
Is held in the closed position by.

Further, the shaft 18 is provided with a pulley 33 at one of its ends projecting to the outside of the cylinder head 11, and this pulley is rotated by a toothed belt 34 driven by the rotational movement of the crankshaft 52. To be

The movable part 13 is, for example, a plurality of bolts 5.
A gasket or seal ring 58 is provided on the outward side, which is fixed to the cylinder head 13 by 7 and corresponds to the point where the front bearing 19 is connected to the shaft 18.

In the first example, as shown in FIGS. 1-3, the shaft 18 is a hollow shaft and has a hole or radial opening 62 which faces the inlet duct 63. This duct 63 is arranged in such a way that the two pipes 64 used for air or air with fuel and / or oil supplied by the equipment of the injector 15
And 65.

It will be appreciated that air, oil and / or fuel is then fed into the chamber 16 via the respective duct and hollow shaft 18. In Fig. 3,
If the fuel supply injector 15 is present in the inner head,
Pipe 64 supplies air, pipe 65 supplies oil
I do. If there is no fuel injector 15 in the cylinder head,
Pipe 64 supplies air and pipe 65 supplies fuel and
Supply il.

In the following examples (FIGS. 5, 6 and 8), the same members as above are given the same numbers, but in these examples the shaft 18 is not hollow and the space sleeve 35
, Which are retained in the projecting portion 17 by a cover (not shown) of interest.

A seal ring 36 is provided between the bearing 19 and the plate-shaped portion 20.

In another embodiment of the cylinder head according to the invention of FIGS. 5 to 9, there is a duct 37 in the inner chamber 16 instead of the end outlet part of the hollow shaft. This duct 37
Is used for air or air added to the fuel and / or oil supplied by the equipment of the injector 15, as if it had a hollow shaft.

The end of the duct is closed in the second example of FIG. 5 by a valve-like member consisting of at least one slice 38. The maximum flakes opening is determined by a rigid stop member 39 secured by screws 40 at one end of the flakes.
In FIG. 5, the fuel supply injector 1 is installed in the cylinder head.
5, the injector 15 supplies fuel and
37 supplies air and oil. In FIG.
If the cylinder head does not have the fuel supply injector 15,
Act 37 supplies air, oil and fuel.

FIGS. 6 and 7 show a third embodiment of the invention in which the same elements are given the same numbers.

In this embodiment, the valve members are given different shapes. In fact, the duct 37 ends in a series of different openings 41, here four openings in combination with four petal-shaped flakes 42. The petal-shaped thin piece 42 to which the bolt 43 is applied is fixed to a strong stopping member 44 conforming to the shape.

FIGS. 8 and 9 show a fourth embodiment of the invention in which the same elements are given the same numbers. In this alternative embodiment, the valve member is a swivel disc 4.
5 is comprised.

This disc 45 made of very light material
Are fixed to the pins or crankpins 21 by means of steady pins 46 and are actuated in the rotational direction by the plate-like parts 20. Furthermore, said disc 45 is pinned at 47 in the center to the wall of the inner chamber 16. FIG. 9 shows that when the disk 45 rotates around the pin 46, the duct 3
7 is shown to have a dimension somewhat larger than the circumference, such as opening and closing.

However, in all of the above-mentioned embodiments, the piston 23 in the chamber 16 allows a direct injection of the fuel, which is pneumatically assisted by the air supplied into the combustion chamber 12 of the lower cylinder.

Briefly, the operation of the cylinder head of the present invention can be described as follows.

With respect to the above examples, the installation of the injector 15 supplies air either through the hollow shaft 18 or the duct 37, or air enriched with fuel and / or oil.

The mixture thus obtained is, in various given cases, compressed by the injection piston 23 as it passes through the convex lateral portion 26 in the lower portion 24 of the chamber 16. The pressure generated between the injection piston 23 and the valve seat 28 overcomes the elastic force of the radial disc spring 31 and allows the mushroom shaped valve 29 to descend, so that the mixture injection into the lower combustion chamber 12 is effected. You can

The cylinder head of the present invention eliminates the need for high pressure air supplied into chamber 16 and avoids the use of unique equipment. In this way, the problems associated with the need for expensive components and the timing of the high pressure air supply and the fuel supply by the injector and solenoid valve are eliminated.

In the first embodiment, the inlet duct 6
The direct supply of oil through 3 ensures a sufficient amount of lubrication means for the correct operation of all parts, eliminating the need for a supply container.

A further illustrated embodiment using one or more flakes such as a valve member ensures a good seal during the compression stage while at the same time a swivel disc with a smaller seal, especially at low speeds. Examples were provided having. In any case, the cylinder head of the present invention allows a significant reduction of the dead space in the crankcase of the precompression pump while still having the advantage of good suction efficiency even at relatively low speed reciprocating pumps.

The particularly simplified construction and operation of the cylinder head for an internal combustion engine according to the invention considerably reduces the cost, which is particularly suitable and advantageous for two-stroke engines.

The main features and aspects of the present invention are as follows.

1. A valve opening and a fuel supply means
Emptying of fuel into at least one cylinder equipped with
SILIN FOR INTERNAL COMBUSTION ENGINE HAVING DEVICE FOR QI-ASSISTED DIRECT INJECTION
In the Darhead, connect to the valve on one side
On the other side air, or fuel and / or oil
Communicated to the supply means of the air added with the chamber, and the
A piston that operates in a chamber,
The air-fuel mixture into the cylinder at least
Comprises a piston for injecting through a Kiben opening, said piston
The ton is driven by the transmission means driven by the crankshaft.
It is operated mechanically and the piston is
Slidable within a lower extension of the chamber bounded
And these parts of said extension are at least one duct
To connect the upstream and downstream of the piston via
Characteristic cylinder head for internal combustion engine.

2. The cylinder head for an engine as described in the above item 1, wherein the means for supplying the air or the air to which fuel and / or oil is added has a duct.

3. The valve-shaped member facing the chamber is provided at an end of the duct.
The engine cylinder head described in the section.

4. The engine cylinder head as described in the above item 3, wherein the valve member is made of at least one thin piece.

5. A cylinder head for an engine as described in the above item 4, wherein a strong stopping member is connected to the at least one thin piece.

6. The above-mentioned item 4, characterized in that said at least one lamina is a petal-shaped lamina and each petal of said at least one lamina is placed in correspondence with various openings associated with said duct. The engine cylinder head described.

7. The cylinder head for an engine as described in the above item 3, wherein the flaky member is a swivel disc that closes the duct.

8. The swivel disc is anchored to a pin or crankpin by means of a steady pin, which is therefore driven by rotation of the transmission shaft of the piston, the disc being pinned at its center to the wall on which the outlet end of the duct rests The engine cylinder head described in the above item 7, characterized in that

9. The cylinder head for an engine as described in the above item 7, wherein the disk is slightly larger than the size of a semicircle.

10. The supply duct comprises at least a portion of a hollow shaft rotatably supported in the chamber, the hollow shaft being driven in the rotational direction by the reliable transmission and being eccentrically pinned to one end of the connecting rod. A cylinder head for an engine as described in the above item 2, characterized in that it has a portion facing the inner portion of the chamber, and the other end of the connecting rod is pivotally attached to the piston.

11. The hollow shaft extends outwardly from the cylinder head to support a pulley driven by a toothed belt rotated by a second pulley fixed to the crank shaft. The engine cylinder head described in item 10.

12. The valve housed in the valve opening is
It is a mushroom type valve that slides inside the valve seat and is guided.
Maintains the valve in a position to close the valve opening when below
The elastic member is provided for the second item.
The cylinder head for the engine described in.

13. An engine cylinder head as described in paragraph 12 above, wherein the at least one duct is a laterally outwardly convex portion within the jacket.

14. The valve housed in the valve opening is a mushroom-shaped valve that is slidably guided in a valve seat, and an elastic member that maintains the valve in a position that closes the valve opening when in a rest state is provided. The engine cylinder head described in the above item 1.

15. Item 14 above, characterized in that the valve seat is provided with a downward opening against which the mushroom-shaped end of the valve abuts and a series of holes at its upper end through which the rod slides. Engine cylinder head.

16. The engine cylinder head described in the above item 14, wherein the elastic member is a radial disc spring.

17. A cylinder head for an engine as set forth in claim 16, wherein the rotatably supported parts face away from the cylinder head and the shaft comprises a seal gasket.

[Brief description of the drawings]

FIG. 1 is a side view of a cylinder head according to the present invention mounted on a cylinder of an internal combustion engine.

2 is a cross-sectional view through the upper portion of FIG. 1 inverted, ie through the cylinder head according to the invention.

FIG. 3 FIG. 1 obtained at line III-III of FIG.
FIG. 3 is a cross-sectional view of the cylinder head of FIG.

FIG. 4 is an enlarged detail view of FIG. 3;

FIG. 5 is a partially sectioned side view of a second example of a cylinder head of the present invention.

FIG. 6 is a partially sectioned side view of a third example of a cylinder head of the present invention.

FIG. 7 is a detailed view of the petal-shaped flakes depicted in FIG.

FIG. 8 is a partially sectioned side view of a fourth example of a cylinder head of the present invention. And

9 is a partially sectioned detail of the swivel disk depicted in FIG. 8. FIG.

[Explanation of symbols]

 11 Upper Head 12 Combustion Chamber 13 Movable Part 14 Seat 16 Chamber 17 Projection Part 22 Connecting Rod 23 Piston

Claims (1)

(57) [Claims] 1. A valve and a fuel supply means are provided, and a valve opening is provided.
Air support for fuel in at least one cylinder that has been burned
Cylinder for an internal combustion engine with a device for assisted direct injection
In the head, the valve is connected to the valve on one side and empty on the other side.
Supply of air or air with fuel and / or oil
A chamber connected to the feeding means and a piston operating in said chamber,
The air-fuel mixture created in the cylinder
And a piston for injecting through the valve opening, the piston being driven by a crankshaft.
Driven mechanically by the piston before the piston is bounded by the jacket
It is slidable in the lower extension of the writing chamber, these parts of said extension being connected by at least one duct.
And connecting the upstream and the downstream of the piston.
Cylinder head for internal combustion engine.