Device for accurate positioning of an object on a frame

1. A device for positioning a printhead in an opening of a frame in a predetermined position with respect to a plane extending in the direction of the plane of the frame (plane X-Y), wherein the printhead includes a first spherical segment provided on a first side and a second spherical segment provided on a second side situated opposite the first side and the frame comprises a positioning means which, after placing the printhead, exerts a force with a component in the radial and tangential direction on the printhead at the first spherical segment, the tangential component reaching a minimum in the situation in which the printhead is situated in the predetermined position, and a recess in which the second spherical segment is pressed by the positioning means.

2. The device according to claim 1 , wherein the frame includes auxiliary means, which prevent movements of the printhead in the direction perpendicularly out of the plane of the frame (Z-direction).

3. The device according to claim 1 , wherein at the positioning means is a resilient element.

4. The device according to claim 3 , wherein the resilient element is a curved leaf spring.

5. The device according to claim 4 , wherein the curved leaf spring is symmetrically shaped and encloses more than one-half of an arc of a circle.

6. The device of claim 4 , wherein straight elements are added to the positioning means.

7. The device according to claim 1 , wherein the positioning means forms a unit with the frame and is formed from the work piece by machining.

8. The device according to claim 1 , wherein the recess is formed as a V-groove.

9. The device according to claim 8 , wherein the recess is conical.

10. The device of claim 1 , wherein the positioning means provides a resilient, self-aligning surface for said printhead.

11. A device for positioning a printhead in an opening of a frame in a predetermined position with respect to an imaginary plane. extending in the direction of the plane of the frame (plane X-Y), the printhead including a first spherically shaped surface segment provided at a first side of the printhead and a second spherically shaped surface segment provided at a second side of the printhead said second side of the printhead being situated opposite said first side of the object, and wherein the frame comprises a recess configured to receive said second spherically shaped surface segment, said frame further comprising at least one positioning means which is configured to exert a force in the situation where the printhead is placed in the frame, said force having a component in the radial direction and the tangential direction on the printhead at said first spherically shaped surface segment, wherein the tangential component reaches a minimum in the situation in which the printhead is situated in the predetermined position.

12. the device according to claim 11 , wherein the frame includes auxiliary means which prevents movements of the printhead in a direction perpendicularly out of the plane of the frame (Z-direction).

13. The device according to claim 11 , wherein the positioning means comprises a resilient element.

14. The device according to claim 13 , wherein the resilient element is a curved leaf spring.

15. The device according to claim 14 , wherein the curved leaf spring is symmetrically shaped and encloses more than one-half of an arc of a circle.

16. The device of claim 14 , wherein straight elements are added to the positioning means.

17. The device according to claim 11 , wherein the positioning means forms a unit with the frame and is formed by machining from a work piece.

18. The device according to claim 11 , wherein the recess is formed as a V-groove.

19. The device according to claim 11 , wherein the recess is conical.

20. The device of claim 11 , wherein the positioning means provides a resilient self-aligning surface for said printhead.