Filter for exhaust gases of a gasoline engine, respectively a diesel engine.
This invention relates to a filter for exhaust gases for a gasoline engine, respectively a diesel engine.
The exhaust gases of these motors are, as is generally known, rather polluting. A substantial part of the polluters could however be captured by filters. To generalise the use of filters and, if necessary, to obligate it, one of the many requirements is that it should be possible for the user to exchange the filtering material regularly and without too many difficulties.
A solution thereto has not yet been found, since the structure of a filter of the said type should moreover comprise technically reliable means to, on the one hand, react to the degree of pollution of the filter, and on the other hand, allow a rapid and simple exchange of at least the filtering part.
To achieve this according to the invention, the filter for exhaust gases of a gasoline engine is designed in combination with a muffler, which muffler is composed of a box with an inlet at the front and an outlet at the back, in which box successively three compartments occur in the direction of circulation of the exhaust gases, which compartments are separated by means of partitions.
namely a frontal compartment to which the inlet is directly connected, a central compartment, wherein the gases enter by means of a central perforated tube which is connected upstream to said first compartment and downstream to a partition, which partition separates said central compartment from a rear compartment, in which rear compartment a cilindrical filter is centrally attached, to remove the purified or substantially purified exhaust gases, which circulate to the outlet through openings in the partition between the central compartment and the rear compartment.
In a preferred embodiment, said back of said box is formed by a detachable sheet with a central tube, which serves simultaneously as an exhaust for the gases and a centralising means for said cilindrical filter, and is said partition which separates the central compartment from the rear compartment, provided with central centralising means in the form of a small pipe, for receiving an end part of said cilindrical filter.
Also according to the invention, said cilindrical filter consists of a double walled perforated cilinder which is filled with a filtering agent.
In case the exhaust gases emanate from a diesel engine, the filter is designed in combination with a muffle, which muffle consists of a box with an inlet at the front and an outlet at the back, which box is subdivided in longitudinal direction in three compartments, namely a frontal compartment to which the inlet is connected and a rear compartment to which the outlet is connected, and an elongated central compartment which is comprised between two partitions which separate said
central compartment from said frontal and rear compartments and consists of an upper part and a lower part, in which elongated central compartment a filter in the form of a sheet is detachably mounted, and in each of said partitions openings are provided for permitting a flow of circulating exhaust gases, in such a way that these gases enter the elongated central compartment via one side of the filter in the form of a sheet and leave the central compartment at the other side of this filter.
Still according to the invention, said box is provided sideways with an elongated detachable cover sheet, with dimensions which permit the passing of said filter in the form of a sheet. In a preferred embodiment of the invention, said filter in the form of a sheet is received in a framework in said box, which framework is formed by three profiles arranged in the form of an U, and said filter in the form of a sheet is formed by a housing which is filled with filter material consisting of perforated sheets.
Other details and advantages of the invention will become clear from the following description Figure 1 is a longitudinal section through a filter for a gasoline engine according to the invention.
Figure 2 is a perspective view of the filter according to figure l, wherein part of the components have been removed.
Figure 3 is a side view, partly a longitudinal section of the filter for a diesel engine according to the invention, wherein some parts have been omitted. Figure 4 is a top view wherein the
filter of figure 1 is partly omitted, wherein the filter is pulled out partly and the cover sheet is removed.
The filter for the exhaust gases of a gasoline engine shown in figure 1 and 2, consists essentially of a combination of a muffle in the form of a box 1, of which the interior is subdivided into three compartments. The different successive compartments, in the direction of the movement of the exhaust gases, are: a frontal compartment 2, a central compartment 3 and a rear compartment 4.
The dimensions of compartment 2 are determined by the distance between the sheet 5 and the partition 6, the dimensions of the central compartment 3 by the distance between the partitions 6 and 7, and the dimensions of the rear compartment by the distance between partition 7 and detachable sheet 8.
The inlet 9 is connected to sheet 5. A central perforated tube 10 extends between the partitions 6 and 7. Upstream, this tube 10 is connected with the frontal compartment 2. Consequently, the exhaust gases consequently pass from the frontal compartment 2 to the central compartment 3, as well through openings 11 which are provided in the central perforated tube 10, as through the openings 12 in the partition 6.
Part of the exhaust gases of the frontal compartment 2 flows via openings 12 to the central compartment 3, because of the necessity to bend away the gases which escape from perforated pipe 10, so that they escape in the direction of a series of openings 13 in the partition 7. The gases from the central compartment 3 reach the rear compartment 4 through these openings 13.
The filter 14 is mounted in such a way in thiε rear compartment 4, that it can be easily removed therefrom and be exchanged for a new one. To allow this, a centralising pipe 15 is provided in the middle of partition 7, and in the middle of the detachable sheet 8, a similar cilindrical tube is provided which constitutes the actual exhaust 16. By unscrewing the bolts 17, the detachable sheet 8 can be removed together with the exhaust 16. The bolts 17 are screwed into the openings 18 (fig. 1) of flange
19. The filter easily leaves the rear compartment and consequently a new filter can be mounted in time.
The degree of pollution, thus the degree of blocking, of the filter 14 is indicated by an increasing counterpressure in the frontal compartment 2. Thereto, a sensor 20, which fulfills a double function, is provided at the side of this frontal compartment 2. On the one hand this sensor activates an alarm light, which informs the driver about the degree of pollution, thus blocking of the filter 14, while on the other hand, when the counterpressure in compartment 2 is further increased, a valve 21 of the by-pass 22 is opened. Consequently the counterpressure in the compartment 2 drops tot the desired level.
The filter for the exhaust gases of a diesel engine according to figures 3 and 4, consists of a box 31 in the form of a muffle, which box consists, in the direction of the movement of the exhaust gases, successively of a frontal compartment 32, a central compartment 33 and a rear compartment 34.
The inlet 35 is connected to the frontal compartment 32, while the outlet 36 is connected to the rear compartment 34.
The frontal compartment is closed off, in the direction of the central compartment 33, by means of a parition 37, while the rear compartment 34, also in the direction of the central compartment 33, is closed off by a partition 38. In the upper part of the partition 37, several passways 39 are provided, while several openings 10 are provided at the bottom of partition 38.
The polluted exhaust gases thus reach the upper part 33a of the central compartment 33, via the passways 39 and leave the lower part 33b of the central compartment 33 through the openings 40.
Since the box 31, along a cross section, is of a substantially elliptical shape, the larger axis of which ellips lays in the longitudinal symmetry plane of the filter 41, above this filter a space is created, which space is equal to the space below this filter. The filter used herein is a filter 41 in the form of a sheet, filled with rockwool of a technically equivalent product, which is capable of collecting the polluting dust particles. The filter 41 in the form of a sheet is constituted of a metal housing, wherein several openings 33 are provided. Due to the sheet structure of the filter 41, a very large filtering surface is created. The filter 41 is indeed substantially located in the longitudinal symmetry plane of box 31, to which also the larger axis of the ellips belongs which corresponds with the cross-section of the box 31. The filter 41 easily slides in and out of a framework, which is constituted by three profiles 44 arranged in the form of an U.
The box 31 is closed off sideways by a cover sheet 45 with a handle 46, and shows an elongated opening to allow the filter 41 to pass.
Because the filter 41 in the form of a sheet fits the three profiles 44 arranged in the form of an U, both compartments are well separated from each other at the upper and the bottom side. At the side of the cover sheet, which closes off the box 31 along one side in the longitudinal direction, the filter in the form of a εheet is also pushed against said cover sheet 45, so that a good or at least sufficient air tight sealing is also assured here. The exhaust gases should thus circulate over the entire surface of the filter 41 in the form of a sheet and through the filter material. Because of the very simple but technically reliable structure of the filter according to the invention, the user of a car can exchange a polluted filter by another one, in time, in a simple way.
In case the pressure in the frontal compartment 32 rises due to the pollution of the filter, the automatic valve which is mounted at the bottom of partition 37 opens, and the polluted gases will be guided to the bottom part 33b of central compartment 33. These gaseε then circulate in an unfiltered εtate through the bottom part 33b of central compartment 33 and leave the box 31 through the rear compartment 34 and outlet 36.
From the description of a filter for the exhaust gases of the gasoline engine according to the invention, it should be clear that a filter which is mounted in a muffle which also serves as a housing for the diferent components, the polluting, harmful, dust particles of the exhaust gases are reliably collected and filtered off. It should also be clear that the degree of pollution of the filter can be rapidly detected, while a polluted and blocked filter can be exchanged by a new one in a very simple way.
This can be performed by every driver or user of the vehicle. This indeed constitutes the essential advantage of the invention.
It should also be stressed that the filter mounted in the muffle has a sound-insulating effect.