Grid arrangement for X-ray apparatus

1. Grid arrangement for use with an X-ray apparatus that is provided with an X-ray source and a recording element, it being possible, in operation, to place the grid arrangement against the recording element and the grid arrangement being equipped to accommodate a flat grid that comprises a multiplicity of elongated thin lamellae, the lamellae being placed essentially parallel to one another in a direction parallel to one surface of the grid, and the lamellae being oriented towards a focal axis a specific distance above the surface of the grid, and the grid arrangement having drive means which are equipped to move the grid in a pendulum movement essentially about an axis of rotation, wherein the grid arrangement further comprises adjustment means for adjusting the axis of rotation of the pendulum movement to match the focal axis of the grid.

2. Grid arrangement according to claim 1 , wherein the grid is made as a flat plate.

3. Grid arrangement according to claim 1 or 2 , wherein the focal axis of the grid is between 100 cm and 250 cm away from the grid.

4. Grid arrangement according to claim 1 , wherein the grid arrangement further comprises a reading device for detecting how far the focal axis is above the grid, the reading device being connected to the adjustment means and the adjustment means being equipped to adjust the axis of rotation of the pendulum movement to match the detected focal axis of the grid.

5. Grid arrangement according to claim 1 , wherein the drive means comprise a first and a second adjustable body provided with a first and a second slot in which fixing means for the grid can be moved back and forth, the first and second slots making an obtuse angle with respect to one another.

6. Grid arraignment according to claim 5 , wherein the obtuse angle is an angle of between 135° and 180°.

7. Grid arrangement according to claim 5 , wherein the first and second adjustable bodies can be rotated about a first and, respectively, second pivot point, the adjustable means further comprise an adjustment body having a longitudinal axis from a first end to a second end, which adjustment body is provided at the first and the second end with a first and, respectively, a second guide slot, which guide slots are essentially parallel to one another and make a first and, respectively, second angle with the longitudinal axis of the adjustment body, the first guide slot is fixed by a rotary coupling to the first adjustable body and the second guide slot is fixed by a further rotary coupling to the second adjustable body, in such a way that the obtuse angle between the first slot and second slot is changed by displacement of the adjustment body along the longitudinal axis.

8. Grid arrangement according to claim 5 , wherein the second slot has a first section and a second section, the first section forming the obtuse angle with the first slot and the second section making an angle with the first slot that is greater than the obtuse angle.

9. Grid arrangement according to claim 1 , wherein the drive means comprise a drive drum having a guide track at the periphery or the drive drum, and a transmission that can be moved in the guide track and is coupled to the grid, the guide track having a shape such that a rotation of the drive drum results in a back and forth movement of the grid over a certain distance.

10. Grid arrangement according to claim 9 , wherein the drive drum has an ejection track and a changeover device, the changeover device being equipped to connect the ejection track to the guide track on actuation.

11. Grid arrangement according to claim 9 , wherein the drive means are provided with at least two rotary couplings with the grid on either side of the grid, and the two rotary couplings are joined to one another by a shaft.

12. Grid arrangement according to claim 11 , wherein the transmission between drive drum and grid comprises:

a first gear disc and a second gear disc;

a toothed belt that is stretched tautly around the first and second gear discs;

a first pawl provided with a pin for coupling to the guide track, the first pawl being rotatably connected to the toothed belt on one side of the first and second gear discs; and

a second pawl provided with a rotary coupling for coupling to the grid, the second pawl being rotatably connected to the toothed belt on a second side of the first and second gear discs.