Supercharger of an internal combustion engine with a diaphragm having an electrical actuator controlled resonant frequency

Patent metadata

Field	Value
Publication number	US-10704457-B2
Application number	US-201615759110-A
Country	US
Kind code	B2
Filing date	Jul 20, 2016
Priority date	Sep 10, 2015
Publication date	Jul 7, 2020
Grant date	Jul 7, 2020

Abstract

A supercharger for an internal combustion engine includes a supercharger chamber, a diaphragm, an inlet valve, an outlet valve, an exhaust gas line, and an actuator. The diaphragm is positioned in the supercharger chamber and divides the supercharger chamber into an intake chamber and an exhaust gas chamber. The inlet valve and outlet valve are positioned on the intake chamber. The exhaust gas chamber is connected to the exhaust gas line, and to the actuator. The actuator is electrically actuatable, is connected to the diaphragm, and is configured to change a resonance frequency of the diaphragm.

First claim

The invention claimed is:

1. A supercharger for an internal combustion engine, comprising:
a supercharger chamber,
a diaphragm positioned in the supercharger chamber so as to subdivide the supercharger chamber into an intake chamber and an exhaust gas chamber;
an inlet valve and an outlet valve positioned on the intake chamber;
an exhaust gas line connected to the exhaust gas chamber; and
an electrically operable actuator connected to the diaphragm, and configured to change a resonant frequency of the diaphragm.

2. The supercharger as claimed in claim 1 , wherein the actuator includes an electrically operable electrical spring element with a variable spring stiffness.

3. The supercharger as claimed in claim 2 , wherein the electrically operable electrical spring element has:
an armature connected to the diaphragm; and
a coil.

4. The supercharger as claimed in claim 3 , wherein:
the electrically operable electrical spring element further includes a stationary permanent-magnet element and a short-circuiting element positioned along an axial direction of the actuator, and configured to change a magnetic flux through the armature; and
the actuator is further configured such that applying a current to the coil causes a position of the short-circuiting element to vary, in order to change a spring stiffness of the electrically operable spring element.

5. The supercharger as claimed in claim 4 , wherein the actuator is configured to vary the position of the short-circuiting element only between a first extreme position and a second extreme position.

6. The supercharger as claimed in claim 3 , further comprising:
a control unit configured to control the actuator so that the diaphragm oscillates at a resonant frequency of the diaphragm or at a frequency in a range of +1-20% of the resonant frequency.

7. The supercharger as claimed in claim 6 , wherein:
the control unit is further configured to apply current constantly to the coil; or
the control unit is further configured to apply current cyclically to the coil.

8. The supercharger as claimed in claim 6 , wherein the control unit is further configured to apply current constantly to the coil and to superimpose a cyclical current on the constant current.

9. The supercharger as claimed in claim 6 , wherein the control unit is further configured to apply current to the coil synchronously to an internal combustion engine cycle in order to change an oscillation amplitude of the diaphragm without influencing the resonant frequency.

10. The supercharger as claimed in claim 6 , wherein the control unit is further configured to operate the actuator such that current is applied to the coil based on an ignition frequency of an internal combustion engine.

11. The supercharger as claimed in claim 6 , wherein the control unit is further configured to operate the actuator such that current is applied to the coil based on a rotation speed of an internal combustion engine.

12. The supercharger as claimed in claim 1 , wherein at least one of the inlet valve and the outlet valve is a non-return valve.

13. The supercharger as claimed in claim 1 , wherein the diaphragm is a stainless steel diaphragm.

14. The supercharger as claimed in claim 6 , wherein the control unit is further configured to control the actuator so that the diaphragm oscillates in a range of +/−10% of the resonant frequency.

15. The supercharger as claimed in claim 9 , wherein the control unit is further configured to apply current to the coil synchronously to the internal combustion engine cycle in order to increase the oscillation amplitude of the diaphragm without influencing the resonant frequency.

Assignees

• Bosch Gmbh Robert

Inventors

• Baeuerle Michael
• Nau Michael

Classifications

• F04B45/047

  Pumps having electric drive · CPC title

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02B33/32

  Engines with pumps other than of reciprocating-piston type (with crankcase pumps F02B33/02) · CPC title

• F02B29/00

  Engines characterised by provision for charging or scavenging not provided for in groups F02B25/00, F02B27/00 or F02B33/00 - F02B39/00; Details thereof · CPC title

• F02B33/42

  with driven apparatus for immediate conversion of combustion gas pressure into pressure of fresh charge, e.g. with cell-type pressure exchangers · CPC title