SU1358A1 - Two stroke internal combustion engine - Google Patents

Description

The invention relates to a device for increasing the speed of such two-stroke internal combustion engines, which have double-acting air pumps for compressing the required purge air and, in particular, such engines that operate with relatively heavy fuel oil. The invention aims at a faster engine speed, due to the possibility of obtaining more power from a small engine than it has been until now. In two-stroke internal combustion engines, the increase in speed or speed per unit of time is limited, since the release of burnt gases from the working cylinders and replacing them with fresh air between each working stroke requires a certain time, and since every second stroke of the two-stroke engines represents a working stroke then it follows that the possible large number of engine revolutions largely depends on the speed with which the gases in the cylinders are replaced. By using an appropriate double-acting air pump that compresses the purge air in a special chamber where it is constantly under pressure, the possible engine speed can already be increased if the pressurized purge air is supplied to the cylinder simultaneously from both ends, as explained below. The subject matter of the invention is shown in the accompanying drawing, as applied to a two-cylinder engine. FIG. 1 shows a section through the cylinders along line ab of FIG. 2, which in turn depicts a horizontal section along the line c-d of FIG. 1, in FIG. 3-section along the line ef of FIG. 1, in FIG. 4-section along the line g-h of the same figure. The drawing shows the cylinders of a vertical engine, but the invention can be equally applied also to a horizontal engine. Both working cylinders are indicated in the drawings by the numbers i and 2. The air pump cylinder is interrupted between the working cylinders, as indicated in the drawing, although it can be placed in

another place. The air pump must be double acting and fresh air is forced through holes in the middle of the cylinders. The air is expelled from the air pump through valves at both ends of its cylinder (not shown in the drawing); compressed air is collected in the compression chamber (fig. 1), which forms the floor, common to all cylinders, the cover, where pressure is constantly maintained by a pump. This known device for compressing air does not fall within the scope of the invention and may be made differently, since it is only necessary for the invention to obtain compressed air, no matter how it is received or from where it is supplied to working cylinders. The application of the invention to engines with the air compression device described above is intended to be simplified, since air ducts can be arranged inside the walls of the cylinders.

The working cylinders have air inlets at their ends distant from the engine frame; these openings are controlled by valves 6 (Fig. 1). After the final stroke, the burnt gases escape through the openings 7 in the wall of the cylinders, which are opened by the piston when the latter approaches the end of its stroke. In addition, there are still other air inlet openings 8, which lead to the working cylinders and are constantly openly connected to the compression chamber / via channels c / (Fig. 2), running along the cylinder of the air pump. These air inlets are diametrically opposite the outlet holes y, they are of such size and location that the outlet openings y open earlier than the openings 8. The shape of these openings is chosen so that the outlet openings 7 are already half open when the inlets 8 is still starting to open, and that the full opening of both holes occurs simultaneously.

With air cooled engines, channels may be placed to introduce compressed air near the ends of the cylinders facing the engine frame; with water cooled engines, they are placed as indicated in the drawing, namely, that between the water jacket and the cylinders at the height of the inlets 8 there is a transverse channel h (Fig. 2-4), which is connected by means of the described longitudinal channels p with a squeeze camera.

At the end of the working stroke, the gases are released through the openings 7 while these openings alone are open. After that, the openings 8 will also open and the incoming air will drive the remains of the burned gases at high speed out of the cylinders. Valves 6 will also open almost simultaneously and fresh air will quickly fill the cylinder from the other end. The device described makes it easier to completely replace the gases in the cylinder, and the engine speed rises without reducing the efficiency.

SUBJECT OF THE PATENT.

A two-stroke internal combustion engine, characterized in that the purging takes place from both ends of the cylinder through valve 6 in the cylinder head and through slots 5 located at the front end of the cylinder against exhaust ports 7 hours which communicate with the compressed air chamber / longitudinal channels.