External wastegate controller

Abstract

The present disclosure is directed to an external compressed bias gas pressured external wastegate controller. The external compressed bias gas pressured external wastegate controller comprises: an upper body portion having a compressed gas bias chamber and a lower body portion having a boost reference chamber; a boost reference port into the boost reference chamber to provide a boost reference pressure from a turbocharger compressor outlet; a bias chamber vent port configured to receive a bias pressure vent solenoid, the vent solenoid configured when actuated to remove compressed bias gas from the bias chamber; a bias gas injection port configured to receive a bias pressure compressed gas injection solenoid, the solenoid configured when actuated to inject compressed bias gas into the bias chamber; a pressure sensor port into the bias chamber; an actuator stem having an upper end and a lower end configured to actuate a wastegate bypass valve; and a diaphragm disposed intermediate the bias chamber and the boost reference chamber and being associated with the stem, the diaphragm movable between a closed position wherein the stem maintains the wastegate bypass valve closed, towards an open position correspondingly moving the stem such the wastegate valve moves to bypass exhaust gas; wherein the upper end of the stem is biased to move the wastegate bypass valve towards the closed position. 20 26 20 21 59 19 M ar 2 02 6 E X T E R N A L W A S T E G A T E C O N T R O L L E R 2 0 2 6 2 0 2 1 5 9 1 9 M a r 2 0 2 6 E X T E R N A L W A S T E G A T E C O N T R O L L E R 2 0 2 6 2 0 2 1 5 9 1 9 M a r 2 0 2 6 Page 1 of 4 FIG. 1 1 11 14 25 12 2 36 35 30 37 3 21 32 X 31 34 17 33 4 16 5 6 23 18 20 26 20 21 59 19 M ar 2 02 6 1 9 M a r 2 0 2 6 1 4 2 5 1 2 2 2 0 2 6 2 0 2 1 5 9 3 6 3 5 3 0 3 7 2 1 3 2 X 3 1 3 4 1 7 3 3 4 1 6 6 2 3 1 8 F I G . 1 1 9 M a r 2 0 2 6 1 4 2 5 1 2 2 0 2 6 2 0 2 1 5 9 X 3 1 6 2 3 1 8 F I G . 1

Description

Field

[0001] The present invention relates to forced air intake engines and, in particular, to a method and apparatus for a turbocharger or supercharger wastegate control.

[0002] The invention has been developed primarily for use in controlling an external wastegate of an exhaust driven turbocharger and will be described hereinafter with reference to this application. However, it will be appreciated that the invention is not limited to this particular field of use and is applicable to engine crank or belt driven superchargers. Background

[0003] Combustion engines, whether internal combustion or compression, increasingly used forced air intake mechanisms to increase engine performance or to improve efficiency. Most commonly, a turbocharger is connected in line with an engine exhaust which drives a turbocharger impeller before being expelled into a vehicle exhaust system. On a common shaft, an intake impellor forces air into the engine air intake via direct injection or via a carburetor or the like.

[0004] Use of a turbocharger therefore allows more fuel to be burnt in any engine cycle by delivering more air to each cylinder providing more power per stroke. When an engine is in use, throttle position determines exhaust gas flow and prevents a turbocharger being over pressured by the exhaust gas either by too higher rate or pressure of exhaust gas or during transition period of rapidly decreasing throttle input. If the exhaust side of the turbocharger is over a predetermined pressure the impeller shaft drawing air into the intake consequently delivers too much air pressure for the engine and can have significant negative consequences including for the turbocharger structure.

[0005] To avoid this, turbochargers include a wastegate valve to prevent overpressure exhaust driving the turbocharger impeller. Some turbochargers have wastegates built in but many others desirably do not. This is because the boost pressure applied by a turbocharger can be varied using an external wastegate. This is typically achieved by disposing a bypass valve in the 2026202159   19 Mar 2026 exhaust gas supply and most conveniently exhaust is bypassed around the turbocharger directly into the exhaust stream, or in some cases to the atmosphere.

[0006] The valve can, most simply, seal a bypass conduit mounted to the exhaust before the turbocharger. As the valve is moved, exhaust gases bypass the turbocharger to reduce impellor drive forces and reduce corresponding air intake. It is well known to use an actuator operated in response to exhaust pressure exceeds a set amount by moving the valve to bleed exhaust gas. A compression spring is often used to exert a bias on the wastegate valve which is overcome by a set pressure.

[0007] In addition, some turbochargers use an external compressed gas supply to increase or decrease the bias of the spring. This bias gas supply includes a conduit acting as a bias gas pressure line connected to the wastegate controller to selective increase pressure by adding pressurized bias gas from the external supply to correspondingly increase or add to spring bias increasing resistance to opening the wastegate valve. A bias gas vent, typically to atmosphere, is used to remove or vent bias external bias gas to reduce the spring bias thereby altering the boost pressure needed by the exhaust to move or open the wastegate valve.

[0008] Unfortunately, external wastegates are often added to a vehicle turbocharger to allow for controlled boost pressure before the wastegate actuates to bypass exhaust gas. In many cases, the external wastegate is added to an engine is an aftermarket accessory to a turbocharger not having a wastegate provided by the original equipment manufacturer (OEM), or in cases where a turbocharger is added to a non-turbocharged OEM engine. As modern engines particularly become more efficiently packaged within a vehicle, space available to insert boost vent and boost fill solenoids and connecting those via a T-piece to the wastegate controller can be highly restricted. Furthermore, the manifold volume of the connecting element between the boost vent and fill solenoids complicates the additional removal of boost pressure.

[0009] It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to at least provide a useful alternative thereto. 2026202159   19 Mar 2026 Summary of Invention

[00010] According to a first aspect of the invention, there is provided an external compressed bias gas pressured external wastegate controller comprising: an upper body portion having a compressed gas bias chamber and a lower body portion having a boost reference chamber; a boost reference port into the boost reference chamber to provide a boost reference pressure from a turbocharger compressor outlet; a bias chamber vent port configured to receive a bias pressure vent solenoid, the vent solenoid configured when actuated to remove compressed bias gas from the bias chamber; a bias gas injection port configured to receive a bias pressure compressed gas injection solenoid, the solenoid configured when actuated to inject compressed bias gas into the bias chamber; a pressure sensor port into the bias chamber; an actuator stem having an upper end and a lower end configured to actuate a wastegate bypass valve; and a diaphragm disposed intermediate the bias chamber and the boost reference chamber and being associated with the stem, the diaphragm movable between a closed position wherein the stem maintains the wastegate bypass valve closed, towards an open position correspondingly moving the stem such the wastegate valve moves to bypass exhaust gas; wherein the upper end of the stem is biased to move the wastegate bypass valve towards the closed position.

[00011] According to a second aspect of the invention, there is provided a method of providing a compressed bias gas pressured external wastegate controller, the method comprising the steps of: 2026202159   19 Mar 2026 providing a body having an upper body portion with a compressed gas bias chamber and a lower body portion with a boost reference chamber; disposing a boost reference port into the boost reference chamber to provide a boost reference pressure from a turbocharger compressor outlet; disposing a bias chamber vent port into the upper body portion for receiving a bias pressure vent solenoid being configured when actuated to remove compressed bias gas from the bias chamber; disposing a bias gas injection port into the upper body portion for receiving bias pressure compressed gas injection solenoid being configured when actuated to inject compressed bias gas into the bias chamber; disposing a pressure sensor port into the bias chamber; providing an actuator stem having an upper end and a lower end configured to engage with a wastegate actuator bypass valve; disposing a diaphragm intermediate the bias chamber and the boost reference chamber and associating the diaphragm with the stem, and configuring the diaphragm to move between a closed position wherein the stem maintains the wastegate bypass valve closed and towards an open position correspondingly moving the stem such that the wastegate bypass valve moves to bypass exhaust gas; and biasing the upper end of the actuator stem to move the wastegate bypass valve toward the closed position.

[00012] According to a third aspect of the invention, there is provided an external compressed gas biased external wastegate comprising: a wastegate body having an inlet configured to receive exhaust gases and an outlet to pass exhaust gases from the inlet therethrough; 2026202159   19 Mar 2026 a wastegate valve configured to close the exhaust gas path between the body inlet and outlet in a first position and to open an exhaust gas path from the inlet through the body in a second position; and the wastegate controller according to the first aspect of the invention, wherein the lower end of the stem is engaged with the wastegate valve such that movement of the stem from the closed position moves the wastegate valve from the first position towards the second position.

[00013] It can therefore be seen there is provided a highly responsive external wastegate controller that also removes the need for the compressed gas boost vent and injection elements to be disposed remotely. Brief Description of Drawings

[00014] A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

[00015] Fig. 1 is a cutaway side view of a compressed bias gas boosted external wastegate controller according to the preferred embodiment; and

[00016] Fig. 2 top view of the controller of Fig. 1;

[00017] Fig. 3 shows the controller of Fig. 1 associated with a wastegate bypass; and

[00018] Fig. 4 schematically shows the relationship between the controller of Fig. 1, and a wastegate bypass and turbocharger. Description of Embodiments

[00019] Referring to the drawings, like reference numerals are used to denote like components. Fig. 1 shows a cutaway side view of an externally supplied compressed gas biased external wastegate controller 1 according to the preferred embodiment. The controller 1 includes an upper body portion 2 having a gas bias chamber 3, and a lower body portion 4 having a boost reference chamber 5. The external compressed bias gas is preferably CO2 or nitrogen or other inert compressed gas. 2026202159   19 Mar 2026

[00020] The controller 1 also includes a boost reference port 6 into the boost reference chamber 5 to provide a boost reference pressure from a turbocharger compressor outlet 7. This is best seen in Fig. 3 showing an example turbocharger 7 and wastegate bypass 8.

[00021] A bias chamber vent port 9 is disposed into the bias chamber 3. The vent 9 receives a bias gas pressure vent solenoid 10. Vent solenoid 10 vents bias chamber 3 gas to atmosphere, however, it can be connected to a closed compressed gas supply (not illustrated) if desired. The solenoid 10 is configured to be actuated to remove compressed bias gas from the bias chamber 3.

[00022] A bias gas injection port 11 is also provided into the bias chamber 3 to receive a bias pressure compressed gas injection solenoid 12. The solenoid 12 is connected to the external compressed bias gas supply. Solenoid 12 is configured when actuated to inject compressed bias gas into the bias chamber 3. A pressure sensor port 14 is also disposed into the bias chamber 3, together with a bias chamber vent port 15 to prevent bias chamber 3 exceeding a predetermined preferred pressure.

[00023] The controller 1 further includes an actuator stem 16 having an upper end 17 and a lower end 18 configured to actuate a wastegate bypass valve 20 (partly shown in Fig. 3) associated with the bypass 8. A diaphragm 21 is disposed intermediate the bias chamber 3 and the boost reference chamber 5. The stem 16 in the preferred embodiment extends through the diaphragm 21 which is associated with the stem 16 in that diaphragm 21 is associated with the stem 16 to accommodate its movement.

[00024] The diaphragm 21 is movable between a closed position wherein the stem 16 maintains the wastegate bypass valve 20 closed, towards an open position correspondingly moving with stem 16 such the wastegate valve 20 moves to bypass exhaust gas in bypass 8. The upper end 17 of the stem 18 is biased by a compression spring 30 to urge or move the wastegate bypass valve 20 towards the closed position.

[00025] In the preferred embodiment, the lower end 18 of the stem extends from the bias chamber 3 through the diaphragm 21 beyond a lower end 23 of the boost reference chamber 5. Movement of the lower end 18 of the stem 16 correspondingly moves the wastegate bypass valve 20. Stem 18 is biased into the closed position. 2026202159   19 Mar 2026

[00026] Additionally, the wastegate controller 1 of the preferred embodiment includes a stem position sensor port 25 configured for receiving a stem position sensor 26. Output from sensor 26 is used to control pressure in bias chamber 3 at a desired level with the compressed bias gas from the external gas supply added to or removed from the bias chamber 3 via bias 11 and vent 9 ports respectively.

[00027] It will be appreciated that stem 16 moves towards the open position in response to a boost reference port pressure exceeding the sum of the bias provided on the diaphragm 21 from the bias chamber 3. The desired or predetermined pressure at which valve 20 is moved towards the closed position exceeds the compressed gas pressure in boost reference chamber 5 which exceeds the pressure of the spring 30 plus the pressure provided by the compressed bias gas in the bias chamber 3.

[00028] In the preferred embodiment, the upper 2 and lower 4 body portions include threaded portions 31 at lower 32 and upper ends 33 respectively for threaded engagement therebetween. An annulus portion 34 of the diaphragm 21 is used to form a seal between body portions 2 & 4 and isolate bias 3 & boost reference 5 chambers. It will be appreciated that any preferred means can be used instead of or additionally to annulus portion 34 to seal body portions 2 & 4 such as a gasket or O-ring

[00029] Also in the preferred embodiment, stem upper end 17 includes element 35 disposed intermediate the position sensor 26 at upper end 36 of bias chamber 3 and upper end 18 of stem 16. Element 35 includes cavity 37 into which upper end 18 of stem 16 can move towards in response to diaphragm 21 moving away from boost reference chamber 5 when pressure in boost reference chamber 5 exceeds pressure on diaphragm 21 applied by the spring 30 and compressed gas in the bias chamber 5. As stem upper end 17 moves into cavity 37 the wastegate valve 20 correspondingly moves from the closed position.

[00030] In use, the bias pressure applied to boost chamber 3 can be made to provide constant pressure or variable pressure as desired. This can be controlled by varying chamber 3 pressure using bias vent 9 and injection 11 ports and controlling compressed gas pressure. In addition, stem position sensor 26 can also be used to provide signals on which to vary the bias chamber 3 pressure. 2026202159   19 Mar 2026

[00031] It will be appreciated that the bias chamber solenoid 12 and bias injection port 11 can be interchanged if desired with bias chamber solenoid 10 bias vent port 9, as well as with bias chamber vent port 15.

[00032] The foregoing describes only one embodiment of the present invention and modifications, obvious to those skilled in the art, can be made thereto without departing from the scope of the present invention.

[00033] The term “comprising” (and its grammatical variations) as used herein is used in the inclusive sense of “including” or “having” and not in the exclusive sense of “consisting only of”.

Claims

1. An external compressed bias gas pressured external wastegate controller comprising:an upper body portion having a compressed gas bias chamber and a lower body portion having a boost reference chamber;a boost reference port into the boost reference chamber to provide a boost reference pressure from a turbocharger compressor outlet;a bias chamber vent port configured to receive a bias pressure vent solenoid, the vent solenoid configured when actuated to remove compressed bias gas from the bias chamber;a bias gas injection port configured to receive a bias pressure compressed gas injection solenoid, the solenoid configured when actuated to inject compressed bias gas into the bias chamber;a pressure sensor port into the bias chamber;an actuator stem having an upper end and a lower end configured to actuate a wastegate bypass valve; anda diaphragm disposed intermediate the bias chamber and the boost reference chamber and being associated with the stem, the diaphragm movable between a closed position wherein the stem maintains the wastegate bypass valve closed, towards an open position correspondingly moving the stem such the wastegate valve moves to bypass exhaust gas;wherein the upper end of the stem is biased to move the wastegate bypass valve towards the closed position.

2. A wastegate controller according to claim 1, wherein the stem extends from the biaschamber through the diaphragm towards or beyond a lower end of the boost reference chamber to correspondingly move the wastegate bypass valve.2026202159   19 Mar 20263.     A wastegate controller according to claim 1 or 2, wherein the stem is biased by acompression spring longitudinally extending from or adjacent the inside of an upper end of the upper body portion.

4. A wastegate controller according to any one of claims 1 to 3, including a stem positionsensor port disposed in the upper body portion and configured for receiving a stem position sensor.

5. The wastegate controller according to any one of claims 1 to 4, wherein the upper andlower body portions include threaded portions at lower and upper ends respectively for threaded engagement therebetween.

6. The wastegate controller according to any one of claims 1 to 5, wherein the diaphragmmoves away from the closed position in response to a boost reference port pressure exceeding the sum of the bias on the stem and compressed bias gas pressure in the bias chamber.

7. The wastegate controller according to any one of claims 1 to 6, wherein the bias pressurechamber vent port and bias chamber injection port solenoids are connected to a closed compressed gas system.

8. The wastegate controller according to any one of claims 1 to 7, including a bias chambervent port into the bias chamber.

9. A method of providing a compressed bias gas pressured external wastegate controller, themethod comprising the steps of:providing a body having an upper body portion with a compressed gas bias chamber and a lower body portion with a boost reference chamber;disposing a boost reference port into the boost reference chamber to provide a boost reference pressure from a turbocharger compressor outlet;2026202159   19 Mar 2026disposing a bias chamber vent port into the upper body portion for receiving a bias pressure vent solenoid being configured when actuated to remove compressed bias gas from the bias chamber;disposing a bias gas injection port into the upper body portion for receiving bias pressure compressed gas injection solenoid being configured when actuated to inject compressed bias gas into the bias chamber;disposing a pressure sensor port into the bias chamber;providing an actuator stem having an upper end and a lower end configured to engage with a wastegate actuator bypass valve;disposing a diaphragm intermediate the bias chamber and the boost reference chamber and associating the diaphragm with the stem, and configuring the diaphragm to move between a closed position wherein the stem maintains the wastegate bypass valve closed and towards an open position correspondingly moving the stem such that the wastegate bypass valve moves to bypass exhaust gas; andbiasing the upper end of the actuator stem to move the wastegate bypass valve toward the closed position.

10. An external compressed gas biased external wastegate comprising:a wastegate body having an inlet configured to receive exhaust gases and an outlet to pass exhaust gases from the inlet therethrough;a wastegate valve configured to close the exhaust gas path between the body inlet and outlet in a first position and to open an exhaust gas path from the inlet through the body in a second position; andthe wastegate controller according to any one of claims 1 to 8, wherein the lower end of the stem is engaged with the wastegate valve such that movement of the stem from the closed position moves the wastegate valve from the first position towards the second position.2026202159   19 Mar 202611. A wastegate according to claim 10, wherein the lower end of the controller body is mounted to a wastegate body.Turbosmart Pty LimitedPatent Attorneys for the Applicant / Nominated PersonSPRUSON & FERGUSON

Images