1. A method of equalizing the pixels in an array of pixels that include semiconductor devices that age differently under different ambient and stress conditions, said method comprising
extracting at least one pixel parameter from said array;
creating a stress pattern for said array, based on the extracted pixel parameter;
stressing said pixels in accordance with said stress pattern;
extracting said pixel parameter from the stressed pixels;
determining whether the pixel parameter extracted from the stressed pixels is within a preselected range and, when the answer is negative:
creating a second stress pattern for said array, based on the pixel parameter extracted from the stressed pixels;
stressing said pixels in accordance with said second stress pattern;
extracting said pixel parameter from the stressed pixels; and
determining whether the pixel parameter extracted from the stressed pixels is within said preselected range.
2. The method of claim 1 in which, when said answer is positive, said array of pixels is returned to normal operation.
3. A method of equalizing the pixels in an array of pixels that include semiconductor devices that age differently under different ambient and stress conditions, said method comprising
creating a stress history of said pixels during a usage cycle;
extracting at least one pixel parameter from said array after the usage cycle;
creating a stress pattern for said array, based on the extracted pixel parameter and;
stressing said pixels in accordance with said stress pattern;
extracting said pixel parameter from the stressed pixels;
determining whether the pixel parameter extracted from the stressed pixels is within a preselected range and, when the answer is negative:
creating a second stress pattern for said array, based on the pixel parameter extracted from the stressed pixels;
stressing said pixels in accordance with said second stress pattern;
extracting said pixel parameter from the stressed pixels; and
determining whether the pixel parameter extracted from the stressed pixels is within said preselected range.
4. The method of claim 3 in which, when said answer is positive, said array of pixels is returned to normal operation.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A differential gear for a multi-axle wheeled vehicle with drive to all axles, comprising
a differential housing (24; DH) which is associated with each wheel pair of the vehicle and is coaxially connected to a respective crown wheel (14; CW) via a connection,
a plurality of differential gears (48, 56: DG), which are rotatably supported in the differential housing (24; DH) and which mesh with a respective drive shaft gear (46, 54; LDSG, RDSG) for a left or a right drive shaft for the wheel pair, the axes of rotation of the drive shaft gears coinciding with the axis of rotation of the crown wheel (14), and
a first, releasable lock (42, 44; C1) between the crown wheel (14) and the one drive shaft,
characterized in that the connection between the crown wheel (14; CW) and the differential housing (24; DH) forms a second, releasable lock (66, 68; C2), and that the differential housing (24; DH) can be connected to a fixed vehicle part (26; FVP) by way of a third releasable lock (74, 76; C3), the second and third locks being designed to be opened and locked alternately with one another.
2. The differential gear as claimed in claim 1, characterized in that the second, releasable lock (66; 68) comprises a clutch ring (70), which is connected so that it is rotationally locked and axially displaceable to the differential housing (24), the clutch ring (70) by way of one end side (66) forming a clutch half that can be rotationally locked to the crown wheel (14).
3. The differential gear as claimed in claim 2, characterized in that the clutch ring (70), via its other side (68) also forms a clutch half that can be releasably connected to a fixed housing part (26) of the differential gear.
4. The differential gear as claimed in claim 2, characterized in that the clutch ring (70) is connected so that it is axially displaceable to the differential housing (24) via a splined connection (72, 73).
5. The differential gear as claimed in claim 3, characterized in that both end sides of the clutch ring (70) are designed with a dog clutch configuration (68, 76) for alternate interaction with a corresponding dog clutch configuration (66) on a first clutch half (64) rotationally locked to the crown wheel (14) and with a corresponding dog clutch configuration (74) on a clutch half connected to the fixed housing part (26).
6. The differential gear as claimed in claim 3, characterized by an operating element (78, 82, 84, 86, 88) for selective axial displacement of the clutch ring (70) engaging and disengaging with the first clutch half (64) rotationally locked to the crown wheel (14).
7. The differential gear as claimed in claim 6, characterized in that the operating element (78, 82, 84, 86, 88) is designed to produce a selective axial displacement of the clutch ring (70) for alternate locking engagement with the crown wheel (14) and the fixed housing part (26).
8. The differential gear as claimed in claim 6, characterized in that the operating element comprises an annular sleeve (78) which surrounds the clutch ring (70) and is provided with driver elements (82) designed for axial lateral displacement of the clutch ring (70) from an engagement position with the crown wheel (14) to an alternative engagement position with the fixed housing (26), and vice-versa.
9. The differential gear as claimed in claim 8, characterized in that the driver elements comprise slide elements (82), which adjoin a radially projecting rib (80) on the clutch ring (70).
10. The differential gear as claimed in claim 8, characterized in that at least three pin-groove mechanisms (84, 86) are evenly spaced in the circumferential direction between the operating sleeve (78) and the surrounding fixed outer housing (26).
11. The differential gear as claimed in claim 10, characterized in that the pins (86) are guide pins anchored in a fixed part (26) of the differential gear and are designed to engage in slanting guide grooves (84) in the operating sleeve (78).
12. The differential gear as claimed in claim 10, characterized in that at least one tangentially acting drive device (88) is designed to rotate the operating sleeve (78) in the circumferential direction whilst allowing a limited axial movement thereof together with the clutch ring (70) by way of the driver elements (82) and the pin-groove mechanisms (84, 86).
13. The differential gear as claimed in claim 1, characterized in that the first releasable lock (42, 44) between the crown wheel (14) and the one drive shaft. comprises a clutch plate (40), which is supported so that it is rotationally locked and axially displaceable on an output shaft (34) in the differential gear, and is designed to be capable of engagement with a second clutch half associated with the crown wheel (14).
14. The differential gear as claimed in claim 13, characterized in that an axially acting drive device is designed to displace the clutch plate (40) supported on the output shaft (34) into and out of an engagement position with the second clutch half associated with the crown wheel (14).
15. The differential gear as claimed in claim 14, characterized in that the first clutch half (64) of the crown wheel (14) is arranged in an outer peripheral part of one side of the crown wheel, whilst the second clutch half thereof is arranged on a radially inner hub part of the other side of the crown wheel.
16. The differential gear as claimed in claim 1, characterized in that the differential gears (48, 56) are supported with their axes of rotation parallel to one another and with the output shafts (34, 50) carrying the drive shaft gears (46, 54) for connection to a left or right drive shaft of the vehicle, the differential gears (48, 56) intermeshing in pairs with one another in an axially overlapping relationship at circumferentially separated points around the output shafts (34, 50).
17. The differential gear as claimed in claim 1, characterized in that the differential gears (DG) are supported with their axes of rotation at right angles to the output shafts (LDS, RDS) carrying the drive shaft gears (LDSG, RDSG) for a left and right drive shaft of the vehicle, each differential gear (DG) meshing with both of the drive shaft gears (LSDG, RSDG) at circumferentially separated points around the output shafts (LDS, RDS).
18. The differential gear as claimed in claim 1, characterized in that the third releasable lock (74, 76; C3) is designed to be kept in the locked position whilst the first lock (42, 44; C1) is in a locked position and the second lock (66, 68, C2) is in the open position, in order to permit rotation of the left and right drive shafts in opposite directions of rotation.
19. A differential gear for a multi-axle, wheeled vehicle with drive to all axles, comprising;
a planetary gear train (DPED) which is associated with each wheel pair of the vehicle and which is coaxially connected to a respective crown wheel (CW) via a connection,
said planetary gear train having a plurality of differential gears in the form of pairs of intermeshing planet wheels (PW1, PW2) at circumferentially separated points and rotatably supported in a planet carrier (PC), in which the one planet wheel (PW1) in each pair also meshes with a surrounding annular wheel (AW) and the other planet wheel (PW2) also meshes with a sun gear (LDSG), the sun gear (LDSG) being designed to be connected to the one drive shaft (LDS) of each wheel pair, whilst the planet carrier (PC) is designed to be connected to the other drive shaft (RDS) of the wheel pair,
and a first, releasable lock (C1) between the crown wheel (CW) and the. one drive shaft (LDS),
characterized in that the crown wheel (CW) can be connected to the surrounding annular wheel (AW) via a second, releasable lock (C2), and that the annular wheel (AW) can be connected to a fixed vehicle part (FVP) via a third, releasable lock (C3), the second and third locks (C2, C3) being designed to be opened and locked alternately with one another.
20. A drivetrain in a multi-axle, wheeled vehicle with drive to all axles for allowing simultaneous rotation of the left and right drive shafts (20a-d, 22a-d; LDS, RDS) of the vehicle in opposite directions of rotation, comprising: cardan shaft sections (18b-d) associated with vehicle wheel pairs, and a pinion (12b-d; CBP), which is associated with each cardan shaft section and which meshes with a crown wheel (14b-d; CW) of a respective differential gear (16b-d), in which each differential gear comprises:
a) a differential housing (24a-d; DH) which is coaxially connected to a respective crown wheel (14a-d; CW) via a connection,
b) a plurality of differential gears (48, 56; DC), which are rotatably supported in the differential housing (24; DH) and which mesh with a respective drive shaft gear (46, 54; LDSG, RDSG) for a left or a right drive shaft of each wheel pair, the axes of rotation of the drive shaft gears being coaxial with the axis of rotation of the crown wheel (14a-d; CW), and
c) first releasable lock (42, 44; C1) between the respective crown wheel and the one drive shaft,
characterized in that the connection between each crown wheel (14a-d; CW) and its associated differential housing (24a-d; DH) forms a second, releasable lock (66, 68; C2), and that the differential housing can be connected to a fixed vehicle part (26; FVP) by way of a third releasable lock (74, 76; C3), the second and third locks being designed to be opened and locked alternately with one another, and the third lock (74,76; C3) being designed to be locked simultaneously with the first lock (42, 44; C1).