DE1451898A1 - Internal combustion engine with exhaust gas turbine and charging fan driven by this - Google Patents

Description

Daimler-Benz Aktiengesellschaft Daim 6510/4

Stuttgart - Untertürkheim October 21, 1964

Dr. Expl.

Patent application

Internal combustion engine with exhaust gas turbine and charging fan ^{w driven by this}

The invention relates to an internal combustion engine with an exhaust gas turbine and the charge fan driven by this, the combustion air promotes in a main charge air line of the internal combustion engine.

The object on which the invention is based is in particular therein, internal combustion engines of the type mentioned in an advantageous manner for use in so-called immediate standby units train that, for example, in the event of a mains voltage failure, the generation of electrical current without any significant interruption have to take over. For this purpose, the internal combustion engine including the charge fan must be switched off in the shortest possible time the standstill to the speed corresponding to their maximum output be accelerated.

When the internal combustion engine starts up, a negative pressure arises in the main charge air line as a result of the throttling effect of the charge blower which is still stationary or rotating at low speed, which means that the internal combustion engine receives too little air and only emits a small amount of exhaust gas energy. Blower only the difference from Abgasturbinett- and supercharger power is consequently effective - at increasing speeds the charging Gebläsee in the main charge air line, an overpressure so that the supercharger to promote against this pressure performance · aufnimat as acceleration performance for the speed increase Lad · created.

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In solving the problem underlying the invention is based on the knowledge that an internal combustion engine of the The type mentioned at the beginning can only deliver its maximum output in the shortest possible time if the charging fan is also used in this period of time is accelerated to its speed corresponding to the maximum output of the internal combustion engine.

To solve the problem and avoid the disadvantages shown in an internal combustion engine of the type mentioned the invention provides that a control element influenced by the delivery pressure or the speed of the charge blower, the main charge air line into a fan-side and a machine-side line section subdivided and has an O-connection for atmospheric pressure, whereby both line sections are below a certain delivery pressure or speed of the charge blower by the regulating element of the main charge air line are connected to the O connection, while Above this delivery pressure or speed, the O connection is blocked and both line sections of the main charge air line are connected to one another.

According to the invention, the charging fan promotes during the acceleration phase only against atmospheric pressure, reducing its power consumption remains low and the acceleration phase is significantly shortened. Another advantage of the invention is that the internal combustion engine when starting via the O-connection of the control element s can suck in immediately with atmospheric pressure, so that a higher amount of exhaust gas energy to accelerate the Ladegebläsea is available.

In an advantageous embodiment of the invention is a Connection piece for atmospheric pressure with the fan-side and the machine-side line section of the main charge air line in connection and can be closed pressure-tight against the atmosphere by a shut-off device, the shut-off device via an actuator can be actuated by a control element influenced by the delivery pressure or the speed of the charge blower. This can be advantageous at the transition from the fan side to the machine side

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Line section of the main charge air line a throttle valve known per se can be arranged, which has a known per se

Angle lever drive is in connection with the shut-off device, the shut-off device by spring force in a manner known per se in held in its open position and against the spring force in its closed position by moving the throttle valve out of its Can be actuated in its closed position in its open end position.

According to the invention, at delivery pressures that do not correspond to a specific speed of the charge blower, both line sections are available the main charge air line via the shut-off element in connection with the atmosphere, so that the charge fan is reached until it is reached this speed only promotes against a relatively low pressure level.

In a further embodiment of the invention, the shut-off element can be formed by a poppet valve opening into the connecting piece whose valve stem is arranged coaxially in the connecting piece

V.

and one in a manner known per se in a rotationally fixed manner with the throttle valve connected angle lever is articulated, wherein a fixed pin of the valve stem engages in an elongated hole of the Y / angle lever . Due to this advantageous design of the shut-off element, its spring force is opposed to the delivery pressure of the charge blower and this acts on the valve plate in the sense of his Closing movement, so that at high delivery pressures the poppet valve is definitely in its closed position and the throttle valve inevitably moved into their open end position releasing the flow cross section of the main charge air line and held there will.

To the valve disc also automatically when reaching a certain To operate the delivery pressure in its closed position, according to the invention have a rigidly attached in the connecting piece Stop for the opening movement of the valve disk and one in the Seat of the iellerventiles overlying throttle cross-section for the valve disk a smaller distance from each other than he Angle of rotation of the throttle valve between its closed position and

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corresponds to their end position. This creates the valve head when immersed in the throttle cross-section regardless of the movement of the throttle valve under the throttle effect by the Delivery pressure pressed onto the valve seat.

In an advantageous embodiment of the invention, a guide bushing can be arranged coaxially in the connecting piece, wherein the guide bushing has a stop surface for the valve disc and axial penetrations for the passage of the combustion air having. So that the poppet valve is opened with certainty when the blower is at a standstill or when the delivery pressure is low is, the invention also sees vot that on the valve disc facing away from the end face of the guide bushing engages a helical compression spring which is arranged coaxially around the valve stem and is supported against a collar of the valve stem, the helical compression spring having such an effective length, that this is effective only between a middle open position and the open end position of the throttle valve is. According to a further feature of the invention, a counterweight effective in the opening direction is connected to the throttle valve in a rotationally fixed manner and so matched to their own weight that the throttle flap by a low delivery pressure of the charge blower in a lower open position is moved. As a result of this coordination, the throttle valve is already at low delivery pressures of the Charging blower lifted off, so that a throttling effect which disadvantageously increases the power consumption of the charging blower is advantageous is avoided.

According to another feature of the invention, the O connection is the Control organ via a known connection line with the Intake line of the charge blower connected. As a result of this connection When starting up, a negative pressure arises in the suction line of the charge blower, so that the power consumption of the blower is effective is decreased. This advantageous effect is further increased by the fact that the air conveyed by the charge fan is increased Temperature. When this heated air is sucked in again by the charging fan, the specific weight of the air throughput is reduced decreased. As a result, Mftk ± the power consumption of the

ORIGINAL INSPECTED _ ₅ _

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biases and its acceleration phase is shortened considerably.

In a known internal combustion engine of the type mentioned at the beginning Art is a device for starting the internal combustion engine so effective that the air sucked in by the fan is completely or partially circulated, heated thereby and fed to the combustion cylinder in this state. To this end, will the charging fan in the known device, however, from an external power source before the internal combustion engine is started driven, with a shut-off body - the one in a connecting line is arranged from the main charge air line to the intake line of the charge blower - when the blower is started up opened and only when the internal combustion engine changes from starting closed to manual operation. Devices and auxiliary drives for starting an internal combustion engine of this type are not the subject of the invention.

Details of the invention can be seen from the drawing, in which an embodiment of the same is shown, and in

1 shows a schematic arrangement of the internal combustion engine and

* 2 show the control element arranged in the main charge air line in a longitudinal section and on an enlarged scale.

In Figure 1, 1 indicates an internal combustion engine, which is from an external drive 2 can be started via a clutch 3 can · On the exhaust side of the internal combustion engine lead a or several exhaust pipes 4 to an exhaust gas turbine 5 »which drives a charging fan 7 via a shaft 6. The charge blower? sucks Combustion air from an intake line 8 and conveys it into a main charge air line 9 leading to the individual cylinders the internal combustion engine leads. A control element 10 is arranged in the main charge air line 9. The one from the control unit 10 to the loading fan 7 leading line section of the main charge air line 9

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is at 11, the line section leading to the internal combustion engine designated by 12. An air filter 13 is arranged in the intake line 8 of the charge blower 7. The one between the charge fan 7 and the air filter The line section of the suction line 8 lying on the 13th is denoted by 14.

According to FIG. 2, that which is arranged in the main charge air line 9 is shown Control element 10 has a connection piece 15 for atmospheric pressure. The connection piece 15 is in the embodiment shown Connected via a connecting line 16 (see FIG. 1) to the line section 14 of the suction line 8 on the fan side. The connection piece 15 is against the atmospheric pressure by a The poppet valve 18, which is arranged with its valve stem 19 coaxially within the connecting piece 15, can be closed. That Disk valve 18 has a valve disk 28 which, in the closed position of the valve, has a valve seat 17 in the connecting piece 15 closes pressure-tight. The Ventxfeitz 17 flows over a throttle cross-section 17a for the valve disk 28 in the connection stub 15. The valve stem 19 of the disk valve 18 is guided by a concentrically arranged in the connection piece 15 guide bushing 20, which for the passage of the combustion air has axial penetrations 21 and is rigidly connected to the connecting piece 15 in a manner not shown.

The fan-side line section 11 of the main charge air line can be closed by a throttle valve 22 which is arranged on a shaft 23 in a rotationally fixed manner. With the shaft 23 is still a Angle lever 24 and an effective in the opening direction of the throttle valve 22 Counterweight 25 rotatably connected. This is matched to the weight of the throttle valve 22 so that already by a certain low delivery pressure a lower opening position III of the throttle valve 22 results.

The angle lever 24 has an elongated hole 26 into which a fixed pin 27 of the valve stem 19 of the poppet valve 18 engages.

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One stop for the opening movement of the valve disk 28 trained end face 31 of the guide bushing 20 has such a dimensioned distance from the throttle cross-section 17a that the The valve disk 28 already dips into the throttle cross section 17a before the throttle flap 22 changes its rotary movement into that indicated by II Has completed the opening end position.

In the opening positions of the throttle valve 22, both line sections 11 and 12 of the main charge air line 9 are connected to the connecting line for as long 16 connected, as the valve disk 28 of the poppet valve 18 is located outside of the throttle cross-section 17a.

The valve stem 19 faces away from the valve disk 28 on its side End of a collar 29 as a stop for a helical compression spring 30, which is concentric to the valve stem 19 between the Collar 29 and an end face 32 on the guide bush 20 is arranged.

The mode of operation of the invention is explained as follows:

When the internal combustion engine starts up, the throttle valve 22 from its drawn closed position I already through the effect of the still low initial delivery pressure into the one marked III moved lower open position. In this, the line sections 11 and 12 of the main charge air line 9 are connected to the intake line 8 via the connecting line 16. The internal combustion engine sucks in combustion air at atmospheric pressure and quickly increases their speed. The charging fan 7 only promotes against atmospheric pressure, whereby the fan speed as a result of increasing exhaust gas energy of the internal combustion engine also quickly increases. The pressure in front of the throttle valve is increased by the increased air flow in the charge fan · The throttle valve is moved under this influence into central opening positions, in which, however, both line sections 11 and 12 of the The main charge air line 9 is connected to the intake line 8. The exhaust gas turbine accelerates as a result of increasing exhaust gas energy 5 the charging fan 7 continues up to its maximum speed.

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In the process, the throttle valve 22 is raised further and the valve 18 is moved in the direction of flow. When reaching a certain Speed or delivery rate - the pressure remains relatively low due to the open line 16 - the valve disk 28 enters the Throttle cross-section 17a on · As a result of the throttling, a rapid pressure increase now occurs and the valve 18 is opened to its Seat 17 pressed, with the throttle valve 22 inevitably reaching its open end position II at the same time.

During the acceleration phase of the supercharger 7, the pressure in the suction line 8 drops, which reduces the power consumption of the Fan is reduced. The same advantageous effect results from the increase in temperature of the amount of air conveyed by the fan, since this is the suction side of the supercharger is supplied again, whereby the specific weight of the air throughput in the charge blower decreases.

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Claims (10)

-9- Paint 6510/4. H51898 claims: 1. Internal combustion engine with exhaust gas turbine and driven by this Charging fan which conveys combustion air into a main charge air line of the internal combustion engine, characterized in that a control element (10) influenced by the delivery pressure or speed of the charge blower (7), the main charge air line (9) into a blower-side and a machine-side line section (11 and 12) subdivided as well as having a 0 connection for atmospheric pressure, whereby by the control element (10) below a certain Delivery pressure or speed of the charge blower (7) both line sections (11 and 12) of the main charge air line (9) with the 0-connection are connected, while above this delivery pressure or speed of the O-connection is blocked and both line sections ι (11 and 12) of the main charge air line (9) are connected to one another. 2. Internal combustion engine according to claim 1, characterized in that the fan-side and the masohine-side line section (11 and 12) of the main charge air line (9) have a common connection piece (15) which is in communication with the atmosphere, which can be closed in a pressure-tight manner against the atmosphere by a shut-off element, the shut-off element via an actuator can be actuated by a control element which is influenced by the delivery pressure or the speed of the charge blower (7). 3. Internal combustion engine according to claim 1 and 2, characterized in that that at the transition from the fan-side to the machine-side line section (11 or 12) of the main charge air line (9) is a per se known (15) is connected, the shut-off element being held in its open position in a manner known per se duroh spring force and against the spring force into its closed position by moving the throttle valve (22) out of its closed position (I) can be actuated in its opening end division (II). 909831/0325 -10- -10- Daim 6510/4 U51898 4. Internal combustion engine according to previous claims, characterized by a poppet valve opening into the connecting piece (15) (18) as a shut-off device, the valve stem (19) of which is coaxial in the connecting piece (15) arranged and on an angle lever connected in a manner known per se to the throttle valve (22) in a rotationally fixed manner (24) is articulated, with a fixed pin (27) of the valve stem (19) in a singing hole (26) of the angle lever (24) intervenes. 5. Internal combustion engine according to previous claims, characterized in that that in the connection piece (15) rigidly attached stop for the opening movement of the valve disk (28) and a the throttle cross-section (I7a) that merges into the valve seat (17) for the valve disk (28) have a smaller distance, when it corresponds to the angle of rotation of the throttle valve © (22) between its closed position (I) and its opening position (II). 6. Internal combustion engine after. previous claims by a guide bushing (20) arranged coaxially in the connecting stub (15) for the valve stem (19) of the poppet valve (18) with a stop surface (31) for the valve disk (28) and axial penetrations (21) for the combustion air. 7 internal combustion engine according to previous claims, characterized in that that on the end face (32) of the Pührungsbuchee (20) facing away from the valve plate (28) there is a helical compression spring (30) engages, which are arranged concentrically around the valve stem (19) is and against a collar (29) of the valve stem (19) is supported. 8. Internal combustion engine according to claim 7 »characterized by a Dtr-like effective length d # r helical compression spring (30) that this is only effective between a middle position and the opening end division (II) of the throttle valve (22). 909831/0325 -11- -11- Paim 6510/4 9. Internal combustion engine according to previous claims, characterized in that that a counterweight (25) acting in the opening direction is connected to the throttle valve (22) in a rotationally fixed manner and so is matched to its own weight that the throttle valve (22) is affected by a low delivery pressure of the loading area (7) is moved into a lower open position (III). 10. Internal combustion engine according to claim 1 and having an intake line for the charging fan, characterized in that the O-connection of the control element (10) via a connection line (16) known per se to the suction line (8) of the charge blower (7) connected is. 90 9 831/0325 ORIGINAL INSPECTED