JPS6235843Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a scavenging air control valve device for an internal combustion engine.

Generally, as an airtight measure for scavenging air control valve devices for internal combustion engines, a gas tight ring (piston ring) is attached to the outer periphery of the cylinder liner below the scavenging hole, and the inner surface of the scavenging air control valve is slidable on this gas tight ring. A press-contact type is used. However, when gas titling is used,
The wear on the ring sliding surface is significant, making maintenance and inspection complicated. Furthermore, since the frictional resistance of the ring portion is large, a large driving force is required on the sliding side (scavenging control valve).

An object of the present invention is to propose a scavenging air control valve device for an internal combustion engine that can limit wear during sliding and can perform sliding with a small driving force.

In order to achieve the above object, the present invention provides a scavenging control valve that covers the scavenging hole portion of the cylinder liner.
A driving device is provided to move the scavenging air control valve to open and close the scavenging air hole, an upper valve seat is provided above the scavenging air hole to which the upper end of the scavenging air control valve can come into contact, and a drive device is provided above the scavenging air hole, and an upper valve seat is provided below the scavenging air hole. A movable seal ring that can be raised and lowered within a certain range relative to the liner is installed.
A lower valve seat is provided at the lower end of the scavenging control valve, and the lower end of the movable seal ring can come into contact with the lower valve seat. According to this configuration, by forming a gap between the inner surface of the scavenging control valve and the outer surface of the seal ring, the sliding movement of the scavenging control valve can be controlled with almost no wear and with a small amount of wear. This can be done using driving force.

Hereinafter, one embodiment of the present invention will be described based on the drawings. 1 is a cylinder liner in which a plurality of scavenging holes 2 are formed. Reference numeral 3 denotes a scavenging control valve that covers the scavenging hole 2, and is moved by the operation of a drive device (such as a cylinder device) 4 to open and close the scavenging hole 2. The upper end surface 3A of the scavenging air control valve 3 is inclined with the outer side facing downward, and the upper valve seat 6 having a hard metal plate 5 on which the upper end surface 3A can come into contact is located above the scavenging hole 2. It is attached to the cylinder liner 1 side. A movable seal ring 7 is provided below the scavenging hole 2 and can be moved up and down within a certain range with respect to the cylinder liner 1. That is, the movable seal ring 7 is attached to the stopper 9 attached to the cylinder liner 1.
It is possible to go up and down within a certain range above. In addition, so as to be in contact with the inner surface of the movable seal ring 7,
A gas tight ring 10 is attached to the cylinder liner 1. A gap 11 is formed in advance between the outer surface of the movable seal ring 7 and the inner surface of the scavenging control valve 3. Also cylinder liner 1
A gap 12 is also formed between the outer surface of the lower edge of the scavenging hole 2 and the inner surface of the scavenging control valve 3. A hard metal plate (seal) 13 is provided at the lower end of the movable seal ring 7 and is inclined upward toward the outer side. It is formed at the lower end of the control valve 3.

FIG. 1 shows a state in which the scavenging control valve 3 is lowered and the scavenging hole 2 is opened. At this time, the movable seal ring 7 descends due to its own weight and is stopped by the stopper 9. In this state, the scavenging control valve 3 is raised by the drive device 4, and the scavenging hole 2 is closed as shown in FIG. At this time, the upper end surface 3A comes into pressure contact with the hard metal plate 5, and the airtightness of the upper part is maintained. Further, in the lower part, the lower valve seat 14 contacts the hard metal plate 13 from below to lift the movable seal ring 7, but at this time, the combustion gas pressure A acts on the upper surface of the movable seal ring 7 through the gap 12. As a result, the hard metal plate 13 is pressed against the lower valve seat 14, and the airtightness of the lower part is maintained.

According to the present invention described above, by forming a gap between the inner surface of the scavenging control valve and the outer surface of the seal ring, the sliding movement of the scavenging control valve is maintained in a state where there is almost no wear. This can be done with a small driving force. In addition, when the scavenging hole is closed by the scavenging control valve, the upper end of the scavenging control valve comes into contact with the upper valve seat, so the upper part can be kept airtight, and the movable seal ring is moved to the lower part by the combustion gas pressure. By being pressed against the valve seat, airtightness of the lower part can be maintained, and reliable airtightness can be maintained while having a simple structure and easy manufacturing and installation.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a longitudinal sectional view of the main parts in the open state, and FIG. 2 is a longitudinal sectional view of the main parts in the closed state. 1...Cylinder liner, 2...Scavenging hole, 3...
Scavenging control valve, 3A... upper end surface, 4... drive device,
5... Hard fillet, 6... Upper valve seat, 7... Movable seal ring, 9... Stopper, 10... Gas tight ring, 11, 12... Gap, 13... Hard fillet, 14... Lower valve seat.

Claims (1)

[Scope of utility model registration request] A scavenging air control valve that covers the scavenging air hole portion of the cylinder liner is provided, a drive device is provided that moves the scavenging air control valve to open and close the scavenging air hole, and an upper valve seat on which the upper end of the scavenging air control valve can come into contact is connected to the scavenging air hole. A movable seal ring is provided above and below the scavenging hole, and is capable of moving up and down within a certain range with respect to the cylinder liner, and the lower end of the movable seal ring is capable of coming into contact with the lower end of the scavenging control valve. A scavenging air control valve device for an internal combustion engine, characterized by having a lower valve seat.