JP2008163915A - Exhaust emission control device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device suitable for an internal combustion engine in which a back pressure increase is preferably avoided, capable of simplifying the structure by smoothly performing exhaust emission control using a single filter, realizing reduction in costs and an occupied space, improving a backwashing effect by securing blowing force of backwashing air, and reducing thermal load of the filter. <P>SOLUTION: When collecting particulate matter, a high pressure air jetting device 171 is not operated, and a blower 160 is operated to suck exhaust coming out of an exhaust passage 200 of the internal combustion engine from a suction part 130 along with outside air in the periphery flowing from an opening part 131 into a contamination side space 111a of a main body case 110, and the particulate matter is collected by the filter 120. The cleaned exhaust is discharged to the outside through a clean side space 111b and a clean side passage 150 of the main body case 110. During backwashing, a bypass valve 182 is opened while keeping the blower 160 operated and negative pressure on the clean side space 111b is released, and the high pressure jetting device is operated to perform backwashing of the filter 120. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an exhaust gas purification apparatus for an internal combustion engine that collects particulate matter from the exhaust gas of the internal combustion engine and discharges the purified exhaust gas.

  Conventionally, as an exhaust purification device that collects black smoke or other particulate matter contained in the exhaust gas of an internal combustion engine, an exhaust passage provided with a filter that collects particulate matter contained in the exhaust is known. (For example, refer to Patent Document 1 and Patent Document 2). In such an exhaust purification device, when the filter is clogged, the filter collection material is removed by blowing backwash air from the exhaust downstream side of the filter to regenerate the filter. In that case, two filters are provided in parallel, and one filter is used to collect particulate matter. If the filter is clogged, switch the exhaust to the other filter and regenerate the clogged filter in the meantime. ing.

  In Patent Document 3, as one of the exhaust gas purification facilities, a high-temperature dust-containing gas is supplied to a bag filter type dust collector to collect the dust, and further, the dust adhering to the bag filter is blown by backwash air blowing. An exhaust gas purifying device that is made to be removed is disclosed. Patent Document 4 discloses a filter device including a pleat filter that is formed in a tubular shape as a whole so that folds on the inside and outside of the pleat are aligned along the circumferential direction.

JP-A-2-185611 JP-A-10-131740 JP 2006-297265 A JP-A-2005-193131

  When a filter is provided in the exhaust passage as in the exhaust gas purification device of Patent Document 1 or Patent Document 2 and exhaust gas is allowed to pass through the filter by its pressure, the back pressure of the exhaust passage increases. However, in an internal combustion engine in which the allowable back pressure is set to be low, such as an internal combustion engine for power generation, there is a demand for suppressing an increase in back pressure caused by providing an exhaust purification device in the exhaust passage. Further, for example, when a performance test is performed by bringing an internal combustion engine into a test bench, there is a demand for preventing an increase in back pressure caused by connecting an exhaust purification device to the exhaust passage from affecting the engine performance.

  Therefore, it is conceivable that a blower is provided on the exhaust downstream side of the filter as in Patent Document 3, and the exhaust is sucked through the filter by this blower, thereby allowing the exhaust to pass through the filter. This is suitable for exhaust gas purification of an internal combustion engine in which the back pressure of the exhaust passage does not increase and it is desired to avoid an increase in the back pressure.

  However, when the exhaust air is sucked using the blower on the exhaust downstream side of the filter, if the backwash air is blown from the exhaust downstream side of the filter toward the filter, the negative pressure atmosphere realized by the blower is obtained. Since backwashing air is blown into the inside, the effect of backwashing is reduced, and the exhaust purification device is unlikely to function normally. This tendency is particularly strong when substances having a small specific gravity are collected in the filter. In that case, it is conceivable to provide two filters in parallel as in Patent Document 1 or Patent Document 2 and use them by switching them. That is, one filter is used to collect particulate matter, and when the filter is clogged, the exhaust is switched to the other filter, while the blower is stopped on the clogged filter side and backwash air is blown in. The filter is regenerated. However, if this is done, two systems of filters and passages are required, which complicates the structure, increases costs, and increases the occupied space.

  Further, depending on the material of the filter, the durability of the filter may be impaired by the heat load caused by the exhaust. In particular, when a bug filter as in Patent Document 3 or a pleated filter as in Patent Document 4 is used, this becomes a big problem.

  The present invention has been made paying attention to such points, and the object of the present invention is to suck the exhaust of the internal combustion engine together with the surrounding outside air by a blower provided on the exhaust downstream side of the filter, and form particulates of the exhaust. Material is collected with a filter, and when the backwash air is blown in, the suction side of the blower is opened to the outside and the negative pressure is eased. An exhaust purification system suitable for internal combustion engines that can reduce back pressure and increase the back pressure, increase the backwash effect by securing the backwash air blowing force, reduce the thermal load of the filter, and avoid back pressure rise It is to provide.

  In order to achieve the above object, an exhaust gas purification apparatus for an internal combustion engine according to the present invention sucks exhaust gas coming out of an exhaust passage of the internal combustion engine together with ambient outside air, collects particulate matter contained in the exhaust gas, and purifies the purified exhaust gas. An exhaust emission control device for an internal combustion engine that discharges. The exhaust gas purification apparatus for an internal combustion engine is provided with a main body case provided with a collection space inside, and provided in the main body case so as to partition the collection space into a contamination side space and a clean side space. A filter that collects particulate matter contained in the main body case, the main body case, provided to communicate with the contaminated space, an inhalation portion provided with an open portion that communicates with surrounding outside air, and the main body case, A discharge part provided to communicate with the clean side space, a clean side passage communicating with the discharge part, a blower provided in the clean side path, and the main body case provided facing the clean side space. A high-pressure air injection device that injects high-pressure air toward the filter, a bypass passage communicating with a portion closer to the main body case than the blower in the clean side passage, and a normally closed bypass valve provided in the bypass passage When the particulate matter is collected, the high-pressure air injection device is deactivated, the blower is activated, and the exhaust gas from the exhaust passage of the internal combustion engine enters the open side of the exhaust air from the inlet to the contamination side space of the main body case. Suction, collect particulate matter with a filter, exhaust the purified exhaust gas through the clean side space and clean side passage of the main body case, and open the bypass valve with the blower open during backwashing. The negative pressure in the space is relaxed, and the high pressure air injection device is operated to perform backwashing of the filter.

  When the particulate matter is collected by performing the purification operation, the high-pressure air injection device is deactivated, the blower is activated, and the exhaust from the exhaust passage of the internal combustion engine enters from the opening portion together with the surrounding outside air from the suction portion to the main body case. The particulate matter is collected by the filter, and the purified exhaust gas is discharged to the outside through the clean side space and the clean side passage of the main body case. On the other hand, when the filter is backwashed by performing the backwash operation, the bypass valve is opened while the blower is operating and the negative pressure in the clean side space is relieved. The blowing force is secured, and the backwashing of the filter is performed strongly.

  In that case, exhaust air is sucked in by the blower, so that an increase in the back pressure in the exhaust passage of the internal combustion engine can be avoided. Further, since exhaust purification is performed by a single filter, the structure of the exhaust purification device can be simplified, the cost can be reduced, and the occupied space can be reduced. In addition, since the blower is not stopped or restarted, the responsiveness is excellent, and the switching between the purification operation and the backwash operation is performed smoothly. When backwashing operation is performed, the negative pressure in the clean side space is relieved, so the amount of exhaust suction is reduced.However, since the suction part is provided with an open part that communicates with the surrounding outside air, exhaust does not enter the body case. When there is no exhaust, the exhaust goes out from the open part. Therefore, the back pressure of the exhaust passage does not increase and the internal pressure of the main body case does not increase. Furthermore, since the exhaust gas discharged from the exhaust passage is sucked together with the surrounding outside air, the exhaust gas temperature is lowered by dilution of the outside air, so that the heat load of the filter is reduced.

  In the exhaust gas purification apparatus for an internal combustion engine of the present invention, the inlet of the suction portion extends in a funnel shape toward the outside, and by disposing the inlet and the end portion of the exhaust passage of the internal combustion engine apart from each other, An open portion may be provided between the end portion of the exhaust passage and the inlet of the suction portion.

  In this way, since it is not necessary to directly connect the suction part of the exhaust purification device to the exhaust passage, it is relatively easy to install the exhaust purification device regardless of the internal combustion engine to be purified.

  The exhaust gas purification apparatus for an internal combustion engine according to the present invention is configured so that an inlet of an intake portion can be connected to an exhaust passage of the internal combustion engine, and an air introduction whose one end communicates with outside air at a portion closer to the main body case than the inlet of the intake portion. The other end of the passage may be connected, and the open portion may be configured by the air introduction passage.

  In this way, since the position of one end of the air introduction passage can be appropriately laid out, the degree of freedom in determining the outside air intake destination and the overflow exhaust destination increases.

  The exhaust gas purification apparatus for an internal combustion engine of the present invention may be provided with a buffer tank having a predetermined volume and communicating with the air introduction passage.

  In this way, exhaust that does not enter the main body case during backwashing accumulates in the buffer tank, so that the exhaust is prevented from overflowing from the open portion to the outside.

  In the exhaust gas purification apparatus for an internal combustion engine according to the present invention, the filter may be a pleated filter including a filtering part formed by winding a folded filter material into a substantially cylindrical shape.

  In this way, the cost of the exhaust emission control device can be reduced by using a pleated filter that is less expensive than a ceramic filter or the like. In addition, since the pleated filter has poor heat resistance compared to a ceramic filter or the like, the effect of improving the filter durability, which is derived by reducing the heat load of the filter due to dilution of the outside air, appears significantly.

  In the exhaust gas purification apparatus for an internal combustion engine of the present invention, a vibration device that applies vibration to the filter or its support member may be provided.

  If it does in this way, the collection substance adhering to the filter by vibration will be screened off.

  The present invention sucks the exhaust gas of the internal combustion engine together with the surrounding outside air by a blower provided on the exhaust downstream side of the filter and collects particulate matter of the exhaust by the filter, and externally connects the suction side of the blower when backwashing air is blown Since the negative pressure is relieved by releasing the air, the exhaust purification by a single filter can be performed smoothly to simplify the structure, reduce the cost and reduce the occupied space, and ensure the backwash air blowing force Thus, the backwashing effect can be improved, the heat load of the filter can be reduced, and an exhaust purification device suitable for an internal combustion engine that wants to avoid an increase in back pressure can be provided.

  The inlet of the intake section is expanded in a funnel shape toward the outside, and the inlet and the end of the exhaust passage of the internal combustion engine are spaced apart from each other, so that the end of the exhaust passage and the inlet of the intake section are spaced apart. When the open portion is provided in the exhaust pipe, the intake portion of the exhaust purification device does not have to be directly connected to the exhaust passage, so that the installation operation of the exhaust purification device is relatively simple regardless of the internal combustion engine to be purified.

  The inlet of the suction portion is configured to be connected to the exhaust passage of the internal combustion engine, and the other end of the air introduction passage whose one end communicates with the outside air is connected to a portion closer to the main body case than the inlet of the suction portion. When the open portion is constituted by the passage, the position of one end of the air introduction passage can be appropriately laid out, so that the degree of freedom in determining the outside air intake destination and the overflow exhaust destination is increased.

  When a buffer tank communicating with the air introduction passage is provided, exhaust can be prevented from overflowing from the open portion to the outside during backwashing.

  When the filter is a pleated filter having a filter part formed by winding a folded filter material into a substantially cylindrical shape, the cost of the exhaust gas purification device can be reduced, and the filter heat load can be reduced by diluting the outside air. The effect of improving the filter durability is noticeable.

  When the filter or its supporting member is provided with a vibration device that applies vibration to the filter, the trapped substance attached to the filter by vibration can be effectively removed.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an exhaust emission control device 100 for an internal combustion engine according to a first embodiment. The internal combustion engine that performs exhaust purification by the exhaust purification device 100 is an internal combustion engine in which fuel is injected into a cylinder, and is a known diesel engine. The internal combustion engine includes a cylinder, a piston slidably fitted in the cylinder, an intake passage that communicates with the cylinder and supplies intake air to the cylinder, and an exhaust that communicates with the cylinder and exhausts exhausted from the cylinder. And a passage 200 (not shown except for the exhaust passage). The intake passage is constituted by a series of internal passages of members such as an air cleaner, an intake pipe and an intake manifold, for example, and intake air introduced from the air cleaner passes through the intake pipe, and intake air is introduced from the intake manifold to the cylinder. The exhaust passage 200 is constituted by a series of internal passages of members such as an exhaust manifold and an exhaust pipe, for example. Exhaust gas from the cylinder is led to the exhaust manifold and released to the atmosphere through the exhaust pipe. The configuration of the intake passage and the exhaust passage is not limited to this. The internal combustion engine of this embodiment is a naturally aspirated internal combustion engine, but the internal combustion engine that is the subject of the present invention includes an internal combustion engine that includes a known exhaust turbocharger. The internal combustion engine that is the subject of the present invention includes an internal combustion engine that uses gasoline as fuel and injects fuel into the cylinder, and also includes a known gasoline engine. The internal combustion engine of this embodiment is an internal combustion engine for driving a power generator and is fixed on a site. However, the internal combustion engine that is the subject of the present invention may be an internal combustion engine mounted on an automobile or other transportation equipment, for example, an internal combustion engine that is fixed on the site even if it is not an internal combustion engine for driving a power generation device The usage is not limited. The form of the internal combustion engine that is the subject of the present invention is not limited by the combustion system of the internal combustion engine that is the subject of the embodiment or other forms.

  The exhaust gas purification apparatus 100 sucks exhaust gas from an exhaust passage 200 of an internal combustion engine together with ambient outside air, collects particulate matter contained in the exhaust gas, and discharges the purified exhaust gas. The exhaust purification apparatus 100 includes a main body case 110, and a collection space 111 is provided inside the main body case 110. Inside the main body case 110, a filter 120 for collecting particulate matter contained in the exhaust is provided. The filter 120 is provided so as to partition the collection space 111 into a contamination side space 111a and a clean side space 111b.

  As shown in FIGS. 4 and 5, the filter 120 is a pleated filter provided with a filtering part 121 formed by winding a folded filter material into a substantially cylindrical shape. The filter medium is formed in a substantially thin plate shape using polyester and PPS, but may have other materials and shapes as long as it has a filtering function. Ceramic filters are superior in heat resistance. As shown in FIG. 5, the crease fold is performed by continuously performing a mountain fold and a valley fold on the filter medium so as to form a continuous W shape. The filter unit 121 winds the filter material folded into a substantially cylindrical shape so that the inner and outer folds of the pleat are aligned along the circumferential direction, and when viewed in the direction of the fold as shown in FIG. A communication portion 121a that communicates with the openings at both ends is formed inside. As shown in FIG. 4 and FIG. 5, one opening of the filtration part 121 has an opening having a shape substantially corresponding to the opening of the communication part 121 a in the vicinity of the center and a diameter substantially equal to the outer diameter of the filtration part 121. A hollow disk 124 having a diameter is provided so as to contact the filter medium, and a disk 125 having a diameter substantially equal to the outer diameter of the filter part 121 is provided in the other opening so as to contact the filter medium. Is blocked. Inside the main body case 110, a partition plate 112 that partitions the collection space 111 together with the filter 120 into a contamination side space 111a and a clean side space 111b is provided, and the partition plate 112 substantially corresponds to the opening of the communication portion 121a. An opening having the shape described above is provided. The filter 120 is arranged on the contamination side space side so that the opening of the hollow disk 124 is aligned with the opening of the partition plate 112. Reference numeral 122 denotes a support member that sandwiches and supports the filter 120 together with the partition plate 112. Therefore, when the exhaust gas in the contamination side space 111a passes through the filtration unit 121 and flows from the communication unit 121a to the clean side space 111b, the particulate matter is collected from the exhaust gas by the filtration unit 121 during this period. Yes. The pleated filter may have another known configuration, and the configuration is not limited by this embodiment. The support member 122 is provided with a known vibration device 123 that applies vibration to the support member 122. The vibration device 123 is, for example, a known air-driven piston vibrator or the like. However, the vibration device 123 may generate vibration based on other operating principles. You may make it provide a vibration apparatus in the filter 120 or the member which contacts it.

  The main body case 110 is provided with a suction portion 130 so as to communicate with the contamination side space 111a. The suction portion 130 is connected to a portion corresponding to the contamination side space 111a in the main body case 110, and is provided by a tube or a tubular member in which a passage extending to the outside and through which the exhaust is passed is formed. You may provide by opening. The suction part 130 is provided with an open part 131 that communicates with surrounding ambient air. In this embodiment, the inlet 132 of the suction portion 130 extends in a funnel shape toward the outside, and the exhaust passage is arranged by separating the inlet 132 and the end portion of the exhaust passage 200 of the internal combustion engine. An open part 131 is provided between the terminal part 200 and the inlet 132 of the suction part 130.

  The main body case 110 is provided with a discharge portion 140 so as to communicate with the clean side space 111b. The discharge part 140 is provided by an opening that opens at a part corresponding to the clean side space 111b in the main body case 110. Instead, there is a passage that is connected to this part and that extends to the outside and passes the exhaust to the inside. You may provide by the formed pipe | tube or the tubular member. A clean side passage 150 communicates with the discharge portion 140. The clean side passage 150 is provided by an internal passage of a pipe or tubular member that is connected to the discharge portion 140 and extends to the outside. A known blower 160 is provided in the middle of the clean side passage 150. The pressure ratio of the blower 160 falls within the category of a general blower, but even if it falls within the category of a pump, it can be applied to the present invention. In one embodiment, for example, the rotational speed of a blower having a maximum discharge pressure of about 6 kPa is controlled, and the pressure difference before and after the filter is used within a range of about 2 to 3 kPa. In this case, the pressure ratio is about 1.03. The main body case 110 is provided with a high-pressure air injection device 171. The high-pressure air injection device 171 is provided facing the clean side space 111 b and exhibits a function of injecting high-pressure air toward the filter 120. In this embodiment, the nozzle part of the high-pressure air injection device 171 is arranged toward the opening of the communication part 121a of the filter 120, and the high-pressure air from the nozzle part is ejected toward the communication part 121a. However, the arrangement of the nozzle portion is not limited to this. The high-pressure air injection device 171 is supplied with high-pressure air once sent from the compressor 173 to the air tank 172, but this configuration does not limit the interpretation of the high-pressure air injection device of the present invention.

  The bypass passage 181 communicates with a portion of the clean side passage 150 closer to the main body case 110 than the blower 160. The bypass passage 181 is provided by a pipe or tubular member having one end connected to a portion closer to the main body case 110 than the blower 160 in the clean side passage 150 and the other end extending to the outside and opened. A bypass passage may be provided simply by providing an opening at this site. The bypass passage 181 is provided with a normally closed bypass valve 182 made of a known valve. The bypass valve 182 is normally closed, but opens when an electrical signal is received. The bypass valve only needs to be a normally closed valve, and does not limit the operating principle or structure. Further, a plurality of bypass passages may be communicated with the clean side passage, and a bypass valve may be provided for each.

  When the particulate matter is collected, the high-pressure air injection device 171 is deactivated, and the blower 160 is activated to exhaust the exhaust gas from the exhaust passage 200 of the internal combustion engine from the suction portion 130 together with the surrounding outside air entering from the opening portion 131. 110, the particulate matter is collected by the filter 120, and the purified exhaust gas is discharged to the outside through the clean side space 111b and the clean side passage 150 of the main body case 110. The bypass valve 182 is opened while the valve is operated, and the surrounding outside air is introduced into the clean side space 111b via the bypass passage 181, thereby relieving the negative pressure in the clean side space 111b and operating the high pressure air injection device 171. The filter 120 is back-washed. In the case of this embodiment, these operations are controlled by the control device 190. The control device 190 is electrically connected to the high-pressure air injection device 171, the bypass valve 182, and the vibration device 123, and sends an electrical signal to these to control the operation of each device. The control device 190 has an electric circuit, and when the set time elapses from the start of operation of the exhaust gas purification device 100, the control device 190 sends an open signal to the bypass valve 182 to open the bypass valve 182, and the high-pressure air injection device 171. The injection operation signal is sent to the high pressure air from the nozzle part toward the communication part 121a for a predetermined time or a predetermined amount, and control is performed to stop the transmission of the open signal to the bypass valve 182 and return to the purification operation. Further, when the same set time as the previous set time or another set time has elapsed since the start of the operation of the exhaust gas purification apparatus 100, an operation signal is sent to the vibration generator 123 to generate vibration. As shown by the dense oblique lines in FIG. 5, the trapping substance T adheres to the outer surface of the filter 120 by the purification operation. However, when the vibration generator 123 generates vibration, the filtration unit 121 vibrates. The trapping substance T adhering to the outer surface of the filter 120 is peeled off from the valley-folded filter medium and collected on the disk 125. In FIG. 4, the collected substances T indicated by the oblique lines are collected, and in FIG. 5, the collected substances T that have fallen on the disk 125 from the specific valley folds of the filtration part 121 are shown by the oblique lines with coarse pitches. ing. The control device may include a computer having a CPU, a memory, and the like. However, the control method at the time of backwashing is not limited to this, and the bypass valve is opened with the blower kept operating to relieve the negative pressure in the clean side space, and the high pressure air injection device is operated to reverse the filter. What is necessary is just to control so that it may wash. For example, instead of controlling the operation of each device according to the set time, it receives a detection signal from a detection means for detecting the load, rotation speed, cooling water temperature, key switch open / closed state or other state quantity of the internal combustion engine. The operation of each device may be controlled by the control device based on them.

  The operation of the first embodiment will be described. As shown in FIG. 2, when the particulate matter is collected by performing the purification operation, the high-pressure air injection device 171 is deactivated, the blower 160 is activated, and the exhaust discharged from the exhaust passage 200 of the internal combustion engine is opened to the open portion 131. From the suction part 130 to the contaminated side space 111a of the main body case 110 together with the surrounding ambient air entering through the filter 120, the particulate matter is collected by the filter 120, and the purified exhaust gas is purified into the clean side space 111b and the clean side passage of the main body case 110. It is discharged outside through 150. On the other hand, as shown in FIG. 3, when the filter 120 is backwashed by performing the backwash operation under the control of the control device 190, the bypass valve 182 is opened while the blower 160 is operating and the negative pressure in the clean side space 111 b is maintained. Therefore, when the high-pressure air injection device 171 is activated, the backwash air blowing force is secured, and the filter 120 is strongly backwashed.

  In that case, exhaust air is sucked in by the blower 160, so that an increase in back pressure in the exhaust passage 200 of the internal combustion engine can be avoided. Further, since the exhaust gas purification is performed by the single filter 120, the structure of the exhaust gas purification device 100 can be simplified, the cost can be reduced, and the occupied space can be reduced. Further, since the blower 160 is not stopped or restarted, the responsiveness is excellent, and the switching between the purification operation and the backwash operation is performed smoothly. When the backwash operation is performed, the negative pressure in the clean side space 111b is relieved, so that the amount of exhaust suction is reduced. However, since the suction portion 130 is provided with an open portion 131 that communicates with the surrounding outside air, the exhaust is When it cannot enter 110, the exhaust goes out through the opening 131. Therefore, the back pressure of the exhaust passage 200 does not increase and the internal pressure of the main body case 110 does not increase. Further, since the exhaust gas exiting from the exhaust passage 200 is sucked together with the surrounding outside air, the exhaust gas temperature is lowered by dilution of the outside air, so that the heat load on the filter 120 is reduced.

  The internal combustion engine exhaust gas purification apparatus according to the present invention is configured so that when the blower is operated, the exhaust gas discharged from the exhaust passage of the internal combustion engine is sucked from the suction portion into the contamination side space of the main body case together with the surrounding outside air entering from the open portion. That's fine. However, in the above-described embodiment, the inlet 132 of the suction portion 130 extends in a funnel shape toward the outside, and the inlet 132 and the end portion of the exhaust passage 200 of the internal combustion engine are arranged apart from each other. The open portion 131 is provided between the end portion of the exhaust passage 200 and the inlet 132 of the suction portion 130. In this way, since the suction part 130 of the exhaust purification device 100 does not have to be directly connected to the exhaust passage 200, the installation operation of the exhaust purification device 100 is relatively easy regardless of the internal combustion engine to be purified. is there.

  The exhaust gas purification apparatus for an internal combustion engine of the present invention does not limit the type of filter. Therefore, a known filter for collecting plugging type, porous body type, fiber type or other particulate matter can be used, and in terms of material, it is particulate made of ceramic, metal or other material. A known filter for collecting substances can be used. However, in the above-described embodiment, the filter 120 is a pleated filter provided with the filtering part 121 formed by winding the folded filter material into a substantially cylindrical shape. In this way, the cost of the exhaust emission control device 100 can be reduced by using a pleated filter that is less expensive than a ceramic filter or the like. In addition, since the pleated filter has poor heat resistance compared to a ceramic filter or the like, the effect of improving the durability of the filter, which is derived by reducing the thermal load of the filter 120 due to dilution of the outside air, remarkably appears. Similar actions and effects can be obtained when a known bag filter is used.

  The exhaust gas purification apparatus for an internal combustion engine according to the present invention may be configured such that the trapped substance attached to the filter is peeled off from the filter by its own weight or the like without providing a vibration device. However, in the above embodiment, the filter 120 or the support member 122 thereof is provided with the vibration device 123 that applies vibrations thereto. If it does in this way, the collection substance adhering to the filter 120 by vibration will be screened off favorably, and the collection substance adhering to the filter can be removed effectively.

  FIG. 6 shows an exhaust emission control device 100 for an internal combustion engine according to the second embodiment. In this embodiment, the configuration of the opening portion of the suction portion is different from that of the first embodiment, but the other configuration is the same as that of the first embodiment. Each part that exhibits the same function as the exhaust purification apparatus 100 of the first embodiment is denoted by the same reference numeral as that used in the first embodiment, and the description thereof is omitted. In this embodiment, similar to the first embodiment, the suction portion 130 is connected to a portion corresponding to the contamination-side space 111a in the main body case 110, and extends to the outside to form a passage through which exhaust is passed. It is provided by a tubular member. The inlet 132 of the suction portion 130 is configured to be connected to the exhaust passage 200 of the internal combustion engine. This is dealt with by providing a flange at the inlet 132 and connecting it to the end of the exhaust passage 200 so that the exhaust does not leak, but other connection structures may be used. The suction part 130 is provided with an open part 131 that communicates with surrounding ambient air. In the second embodiment, the other end of the air introduction passage 133 whose one end communicates with the outside air is connected to a portion closer to the main body case 110 than the inlet 132 in the suction portion 130, and the open portion 131 is connected by the air introduction passage 133. It is composed. Further, a buffer tank 134 is provided in the air introduction passage 133. The buffer tank 134 is provided in such a form that its part is expanded in the middle of the air introduction passage 133 and has a predetermined volume inside. However, the buffer tank 134 may have any form as long as it has a predetermined volume and communicates with the air introduction passage.

  According to the exhaust gas purification apparatus 100 of the internal combustion engine of the second embodiment, the same functions and effects as those of the exhaust gas purification apparatus 100 of the first embodiment can be obtained except for the functions and effects obtained from the funnel shape of the open portion. In the second embodiment, the inlet 132 of the suction portion 130 is configured to be connected to the exhaust passage 200 of the internal combustion engine, and one end communicates with the outside air at a portion closer to the main body case 110 than the inlet 132 of the suction portion 130. The other end of the air introduction passage 133 to be connected was connected, and the open portion 131 was configured by this air introduction passage 133. In this way, since the position of one end of the air introduction passage 133 can be appropriately laid out, the degree of freedom in determining the outside air intake destination and the overflow exhaust destination is increased.

  In addition, since the buffer tank 134 having a predetermined volume and communicating with the air introduction passage 133 is provided, the exhaust that cannot enter the main body case 110 during backwashing accumulates in the buffer tank 134, so that the exhaust is discharged from the opening 131. It is prevented from overflowing to the outside.

  The embodiments and examples described above are merely examples of the exhaust gas purification apparatus for an internal combustion engine of the present invention. Therefore, the exhaust gas purification apparatus for an internal combustion engine of the present invention is not limitedly interpreted by the description and numerical values of this embodiment and examples.

1 is an overall schematic configuration diagram of an exhaust emission control device for an internal combustion engine according to a first embodiment. The support member for the filter and the vibration device are omitted. The signal line exiting the control device and ending with an arrow is connected to the vibration device. It is a figure explaining the flow of exhaust gas when a purification driving | operation is performed with the exhaust gas purification apparatus of the internal combustion engine of 1st Embodiment. The support member for the filter and the vibration device are omitted. It is a figure explaining the flow of exhaust when backwashing operation is performed with the exhaust emission control device of the internal combustion engine of a 1st embodiment. The support member for the filter and the vibration device are omitted. It is a partial longitudinal cross-sectional view of the filter vicinity which showed the filter part of the exhaust gas purification apparatus of the internal combustion engine of 1st Embodiment in cross section. The collected material is shown screened off from the filter by the backwash operation. It is a cross-sectional view showing the vicinity of the filter of the exhaust gas purification apparatus for an internal combustion engine of the first embodiment. A trapping substance is attached to the filter. It is a whole schematic block diagram of the exhaust gas purification device of the internal combustion engine of 2nd Embodiment. The support member for the filter and the vibration device are omitted. The signal line exiting the control device and ending with an arrow is connected to the vibration device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Exhaust gas purification device 110 Main body case 111 Collection space 111a Contamination side space 111b Clean side space 120 Filter 123 Excitation device 130 Suction part 131 Opening part 132 Inlet 133 Air introduction path 134 Buffer tank 140 Discharge part 150 Clean side path 160 Blower 171 High-pressure air injection device 181 Bypass passage 182 Bypass valve 200 Exhaust passage

Claims (6)

An exhaust gas purification apparatus for an internal combustion engine that sucks exhaust gas from an exhaust passage of the internal combustion engine together with ambient ambient air, collects particulate matter contained in the exhaust gas, and exhausts the purified exhaust gas,
A body case with a collection space inside,
In the main body case, the filter is provided so as to partition the collection space into a contamination side space and a clean side space, and collects particulate matter contained in the exhaust,
A suction part provided in the main body case so as to communicate with the contaminated space, and provided with an open part communicating with the surrounding outside air;
A discharge portion provided in the main body case so as to communicate with the clean side space;
A clean side passage communicating with the discharge section;
A blower provided in the clean side passage;
A high-pressure air injection device that is provided in the main body case facing the clean side space and injects high-pressure air toward the filter;
A bypass passage communicating with a portion closer to the main body case than the blower in the clean side passage;
A normally closed bypass valve provided in the bypass passage,
When collecting the particulate matter, the high-pressure air injection device is deactivated, and the blower is activated to suck the exhaust from the exhaust passage of the internal combustion engine from the intake part into the contaminated space of the main body case together with the surrounding outside air entering from the open part. The particulate matter is collected with a filter, and the purified exhaust is discharged to the outside through the clean side space and the clean side passage of the main body case. An exhaust purification device for an internal combustion engine configured to relieve negative pressure and operate a high-pressure air injection device to perform backwashing of a filter.   The inlet of the suction part spreads in the shape of a funnel toward the outside. By arranging the inlet and the end of the exhaust passage of the internal combustion engine apart from each other, the end of the exhaust passage and the inlet of the suction part An exhaust purification device for an internal combustion engine according to claim 1, wherein an opening is provided between the two. The inlet of the suction part is configured to be connected to the exhaust passage of the internal combustion engine,
2. The exhaust gas purification apparatus for an internal combustion engine according to claim 1, wherein the other end of the air introduction passage having one end communicating with the outside air is connected to a portion closer to the main body case than the inlet in the suction portion, and an open portion is constituted by the air introduction passage.   The exhaust gas purification apparatus for an internal combustion engine according to claim 3, further comprising a buffer tank having a predetermined volume and communicating with the air introduction passage.   The exhaust emission control device for an internal combustion engine according to any one of claims 1 to 4, wherein the filter is a pleated filter including a filtering portion formed by winding a folded filter material into a substantially cylindrical shape.   The exhaust emission control device for an internal combustion engine according to any one of claims 1 to 5, wherein the filter or a support member thereof is provided with a vibration device that applies vibration to the filter or the support member.

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