1. Wind stop device for convertible vehicles, comprising:
a wind blocker rising above a belt line of a body; and
a cover connected to the wind blocker for an area, located behind the wind blocker in relation to a direction of travel, of a passenger compartment opening of the body, the wind blocker having an air permeability which is greater than an air permeability of the cover.
2. Wind stop device in accordance with claim 1, wherein the air permeability of the wind blocker is approximately twice the air permeability of the cover.
3. Wind stop device in accordance with claim 2, wherein the air permeability of the wind blocker is at least approximately 2.5 times the air permeability of the cover.
4. Wind stop device in accordance with claim 1, wherein the air permeability of the wind blocker is at maximum approximately five times the air permeability of the cover.
5. Wind stop device in accordance with claim 4, wherein the air permeability of the wind blocker is at maximum approximately four times the air permeability of the cover.
6. Wind stop device in accordance with claim 1, wherein the air permeability of the wind blocker is approximately three times the air permeability of the cover.
7. Wind stop device in accordance with claim 1, wherein the air permeability of the cover is of such size that at an approach velocity of the air of 10 ms towards the cover an air current with a velocity of between approximately 0.5 ms and approximately 2 ms results after the cover.
8. Wind stop device in accordance with claim 7, wherein the air permeability of the cover is of such size that at an approach velocity of the air of 10 ms towards the cover an air current with a velocity of between approximately 0.75 ms and approximately 1.7 ms results after the cover.
9. Wind stop device in accordance with claim 8, wherein the air permeability of the cover is of such size that at an approach velocity of the air of 10 ms towards the cover an air current with a velocity of between approximately 1 ms and approximately 1.5 ms results after the cover.
10. Wind stop device in accordance with claim 1, wherein the cover has an air permeability which varies in a transverse direction extending transversely to the direction of travel.
11. Wind stop device in accordance with claim 10, wherein the air permeability varies symmetrically in relation to a longitudinal center plane extending in the direction of travel.
12. Wind stop device in accordance with claim 1, wherein the air permeability in an inner area of the cover is different than in an outer area of the cover that lies outside of the inner area.
13. Wind stop device in accordance with claim 12, wherein the air permeability in the inner area is lower than in the outer area of the cover.
14. Wind stop device in accordance with claim 1, wherein the wind blocker has an air permeability which varies in a transverse direction extending transversely to the direction of travel.
15. Wind stop device in accordance with claim 14, wherein the air permeability varies symmetrically in relation to a longitudinal center plane extending in the direction of travel.
16. Wind stop device in accordance with claim 1, wherein the air permeability in an inner area of the wind blocker is different than in an outer area of the wind blocker that lies outside of the inner area.
17. Wind stop device in accordance with claim 16, wherein the air permeability in the inner area is greater than in the outer area of the wind blocker.
18. Wind stop device in accordance with claim 1, wherein the wind blocker is formed by a wind blocker frame and a wind blocker frame insert.
19. Wind stop device in accordance with claim 18, wherein the wind blocker frame insert is of air-permeable design.
20. Wind stop device in accordance with claim 19, wherein the wind blocker frame insert is formed from a flat material having a slackness that allows it to be bent.
21. Wind stop device in accordance with claim 20, wherein the flat material having a slackness that allows it to be bent is clamped in the wind blocker frame.
22. Wind stop device in accordance with claim 1, wherein the cover is formed by at least one cover frame and a cover frame insert.
23. Wind stop device in accordance with claim 22, wherein the cover frame insert is of air-permeable design.
24. Wind stop device in accordance with claim 23, wherein the cover frame insert is formed from a flat material having a slackness that allows it to be bent.
25. Wind stop device in accordance with claim 24, wherein the flat material having a slackness that allows it to be bent is clamped in the cover frame.
26. Wind stop device in accordance with claim 1, wherein:
the wind blocker is formed by two wind blocker parts which, in turn, are adapted to be brought by pivoting about a pivot axis from a extended position in which the wind blocker extends with a maximum extent in a direction of extension into a folded position in which the two wind blocker parts lie substantially on top of each other; and
in that the cover is formed by two cover parts.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A method for rapidly controlling the rate of ion generation in an ion source having a filament-cathode and a mirror electrode, the ion source being operable to generate an ion beam from the ionization of ion precursor gas present in the chamber by electrons emitted from the filament, the method comprising the steps of:
supplying current to said filament-cathode;
supplying current to said mirror electrode; and
controlling the potential difference between said filament-cathode and said mirror electrode by modifying the potential of the mirror electrode to control the number of electrons available for ionization.
2. The method of claim 1 further comprising the step of reducing the ion beam intensity by driving the potential of the mirror electrode positive relative to the filament cathode.
3. The method of claim 1 further comprising the step of increasing the ion beam intensity by driving the potential of the mirror electrode to negatively bias the mirror electrode relative to the filament of the ion chamber.
4. The method of claim 1 wherein the filament cathode is a directly heated cathode.
5. The method of claim 1 wherein the filament cathode is an indirectly heated cathode.
6. The method of claim 1 further comprising the step of modulating the number of electrons in a manner that varies the ion beam from a first intensity to a second intensity during a time frame of less than one millisecond.
7. A method for rapidly controlling the rate of ion generation in an ion source having a filament-cathode, a mirror electrode, and at least one grid, the ion source being operable to generate an ion beam from the ionization of ion precursor gas present in the chamber by electrons emitted from the filament, the method comprising the steps of:
supplying current to said filament-cathode;
supplying current to said mirror electrode;
supplying current to the grid, and
controlling the potential difference between said filament-cathode and said grid by modifying the potential of the grid relative to the filament to control the number of electrons available for ionization between the grid and the mirror electrode.
8. The method of claim 7 further comprising the step of reducing the ion beam intensity by driving the potential of the grid positive relative to the filament cathode.
9. The method of claim 7 further comprising the step of increasing the ion beam intensity by driving the potential of the grid to negatively bias the grid relative to the filament cathode.
10. The method of claim 7 wherein the filament cathode is a directly heated cathode.
11. The method of claim 7 wherein the filament cathode is an indirectly heated cathode.
12. The method of claim 7 further comprising the step of modulating the number of electrons in a manner that varies the ion beam from a first intensity to a second intensity during a time frame of less than one millisecond.
13. An improved ion source apparatus for rapidly modulating the intensity of an ion beam, comprising:
an ion chamber having mutually opposed sides and configured to receive ion precursor gas;
a filament-cathode located on one side of said ion chamber and operable to emit electrons for the ionization of the precursor gas for the generation of the ion beam; and
a mirror electrode having a potential associated therewith and located on the other side of said ion chamber, said mirror electrode being connected to a circuit to vary its potential relative to said filament so as to vary the number of the electrons available in the ion chamber for ionization.
14. The apparatus of claim 13 wherein said mirror electrode is operable for modulating the ion beam between a first and second intensity during a time frame of less than 1 millisecond.
15. The apparatus of claim 13 wherein the filament cathode is a directly heated cathode.
16. The apparatus of claim 13 wherein the filament cathode is an indirectly heated cathode.
17. An improved ion source apparatus for rapidly modulating the intensity of an ion beam, comprising:
an ion chamber having mutually opposed sides and configured to receive ion precursor gas;
a filament-cathode located on one side of said ion chamber and operable to emit electrons for the ionization of the precursor gas for the generation of the ion beam;
a mirror electrode located on the other side of said ion chamber, and
at least one grid extending inside said ion chamber and positioned between said filament-cathode and said mirror electrode, said at least one grid being connected to a circuit to vary its potential relative to said filament and being operable so as to vary the number of electrons available in the ion chamber for ionization.
18. The apparatus of claim 17 wherein the filament cathode is a directly heated cathode.
19. The apparatus of claim 17 wherein the filament cathode is an indirectly heated cathode.
20. The apparatus of claim 17 wherein said grid is positioned in proximity to said filament-cathode so as to vary the number of electrons available for ionization between said at least one grid and said mirror electrode.