What is claimed is:
1. An ink-jet writing instrument carriage assembly for an ink-jet printer having a printing axis, a print media transport axis, and an ink drop firing axis, comprising:
a carriage;
a movable pen latch;
a positioning mechanism associated with the pen latch; and
a positioning mechanism retainer associated with the carriage, wherein the carriage and pen latch are each provided with complementary interfit devices such that when the movable pen latch is in a closed position with the retainer interlocked with the handle, the carriage and latch are held by the interfit devices with zero clearance interfit in at least one the axis such that torsional deflections of the carriage are thereby reduced.
2. The assembly as set forth in claim 1, comprising:
a plurality of interfit devices are provided and displaced in the y-axis for holding the carriage and the latch with zero clearance interfit in at least two axes.
3. The assembly as set forth in claim 1, comprising:
the interfit devices setting up counterforces to pen yaw torsional deflection tendencies of the carriage when the pen latch is in a closed position.
4. The assembly as set forth in claim 1, comprising:
the interfit devices setting up counterforces to pen roll torsional deflection tendencies of the carriage when the pen latch is in a closed position.
5. The assembly as set forth in claim 1, comprising:
the interfit devices setting up counterforces to pen pitch torsional deflection tendencies of the carriage when the pen latch is in a closed position.
6. The assembly as set forth in claim 1, comprising:
each of the interfit devices includes a pen latch retainer on the carriage, the retainer including wedge configured receivers having receiver mating surfaces for providing y-axis constraint, and a protruding arm on the pen latch, the arm including a pivot having a surface wherein the pivot is interfit against the surfaces such that the pen latch can be rotatably moved between an open position and the closed position and the interfit provides y-axis, z-axis, theta-y and theta-z constraints for printheads of each pen.
7. The assembly as set forth in claim 1, comprising:
each of the interfit devices includes a pen latch retainer on the carriage, the retainer including wedge-configured receivers having receiver mating surfaces for providing x-axis constraint, and a protruding arm on the pen latch, the arm including at least one face having a geometric configuration for establishing a interfit against at least one of the receiver mating surfaces such that in the closed position, the interfit provides x-axis and z-axis constraints for pen printheads.
8. The assembly as set forth in claim 1, comprising:
the positioning mechanism is a handle and the retainer biases the handle; and
the interfit devices include at least one wedge-configured receiver positioned on the carriage in a region proximate the receiver, the receiver having a mating surface for providing y-axis constraint, and the pen latch having at least one surface having a face having a geometric configuration for establishing a interfit against the mating surface when the pen latch is in the closed position such that the interfit provides y-axis, z-axis, theta-x, and theta-z constraints of pen printheads.
9. The assembly as set forth in claim 1, comprising:
the carriage means and pen latch means complementary interfit devices provide pen pitch, pen roll and pen yaw counterforces when the pen latch means is in the closed position.
10. The assembly as set forth in claim 7, comprising:
the interfit surfaces are provided with surface angles wherein the contact between the surfaces is self-locking.
11. An ink-jet writing instrument carriage assembly, comprising:
carriage means for mounting at least one ink-jet printhead and for scanning across print medium positioned adjacently thereto such that the printhead is positioned with an ink drop nozzle side aligned for depositing ink drops on the print medium and a holddown side aligned for receiving a latching force;
movable pen latch means for accessing the printhead mounted in the carriage means when the latch means is in an open position and for providing a force against a holddown side of the printhead when in a closed position;
fixedly mounted to the carriage means, latch retainer means for receiving the pen latch means via complementary interfit devices of each;
associated with the pen latch means, latch securing means for securing the pen latch means against the carriage means and forcing a interfit between the complementary interfit device; and
mounted on the carriage means, bias means for holding the latch securing means in the closed position,
wherein the carriage means and pen latch means complementary interfit devices provide pen pitch, pen roll and pen yaw counterforces when the pen latch means is in the closed position.
12. The assembly as set forth in claim 11, comprising:
a plurality of interfit devices are provided and displaced in the y-axis for holding the carriage and the latch with zero clearance interfit in at least two axes.
13. The assembly as set forth in claim 12, comprising:
the interfit devices setting up counterforces to pen yaw torsional deflection tendencies of the carriage when the pen latch is in a closed position.
14. The assembly as set forth in claim 12, comprising:
the interfit devices setting up counterforces to pen roll torsional deflection tendencies of the carriage when the pen latch is in a closed position.
15. The assembly as set forth in claim 12, comprising:
the interfit devices setting up counterforces to pen pitch torsional deflection tendencies of the carriage when the pen latch is in a closed position.
16. The assembly as set forth in claim 12, comprising:
each of the interfit devices includes a pen latch retainer on the carriage, the retainer including wedge-configured receivers having receiver mating surfaces for providing y-axis constraint, and a protruding arm on the pen latch, the arm including a pivot having a surface wherein the pivot is interfit against the surfaces such that the pen latch can be rotatably moved between an open position and the closed position and the interfit provides y-axis, z-axis, theta-y and theta-z constraints for printheads of each pen.
17. The assembly as set forth in claim 12, comprising:
each of the interfit devices includes a pen latch retainer on the carriage, the retainer including wedge-configured receivers having receiver mating surfaces for providing x-axis constraint, and a protruding arm on the pen latch, the arm including at least one face having a geometric configuration for establishing a interfit against at least one of the receiver mating surfaces such that in the closed position, the interfit provides x-axis and z-axis constraints for pen printheads.
18. The assembly as set forth in claim 12, comprising:
each of the interfit devices includes at least one wedge-configured receiver positioned on the carriage in a region proximate the bias means, the receiver having a mating surface for providing y-axis constraint, and the pen latch having at least one surface having a face having a geometric configuration for establishing a interfit against the mating surface when the pen latch is in the closed position such that the interfit provides y-axis, z-axis, theta-x, and theta-z constraints of pen printheads.
19. The assembly as set forth in claim 12, comprising:
the carriage means and pen latch means complementary interfit devices provide pen pitch, pen roll and pen yaw counterforces when the pen latch means is in the closed position.
20. The assembly as set forth in claim 17, comprising:
the interfit surfaces are provided with surface angles wherein the contact between the surfaces is self-locking.
21. A method for reducing torsional deflections in an ink-jet writing-instrument carriage, comprising the steps of:
providing the carriage and writing-instrument latch with geometrically configured complementary interfit surfaces; and
positioning the writing-instrument latch on the carriage against a bias such that when the writing-instrument latch is closed, counterforces to carriage torsional deflections which would affect the printhead-to-paper orientation and distance are established by the complementary interfit surfaces.
22. The method as set forth in claim 21 wherein said torsional deflections are associated with printhead yaw, pitch, and roll or any combination thereof.
23. An ink-jet hard copy apparatus having a plurality of ink-jet writing-instruments for ejecting droplets of ink in a printing zone of the apparatus, the apparatus being defined by a scanning axis, a print media transport axis, and an ink drop firing axis, wherein the axes are mutually orthogonal, comprising:
a writing-instrument carriage, mounted in the apparatus for selectively scanning the printing zone along parallel to the scanning axis, the carriage including a plurality of bays for locating the writing-instruments with respect to the printing zone;
a movable writing-instrument latch having an open position for accessing the bays and a closed position for securing the writing-instruments in the bays;
a writing-instrument latch handle associated with the writing-instrument latch; and
a biased handle retainer for the carriage,
wherein the carriage and writing-instrument latch are each provided with complementary interfit devices such that when the movable writing-instrument latch is in the closed position with the retainer interlocked with the handle, the carriage and latch are held by the interfit devices with zero clearance interfit in at least one the axis such that torsional deflections of the carriage are thereby reduced.
24. The assembly as set forth in claim 23, comprising:
a plurality of interfit devices are provided and displaced in the y-axis for holding the carriage and the latch with zero clearance interfit in at least two axes.
25. The assembly as set forth in claim 23, comprising:
the interfit devices setting up counterforces to pen yaw torsional deflection tendencies of the carriage when the pen latch is in a closed position.
26. The assembly as set forth in claim 23, comprising:
the interfit devices setting up counterforces to pen roll torsional deflection tendencies of the carriage when the pen latch is in a closed position.
27. The assembly as set forth in claim 23, comprising:
the interfit devices setting up counterforces to pen pitch torsional deflection tendencies of the carriage when the pen latch is in a closed position.
28. The assembly as set forth in claim 23, comprising:
each of the interfit devices includes a pen latch retainer on the carriage, the retainer including wedge-configured receivers having receiver mating surfaces for providing y-axis constraint, and a protruding arm on the pen latch, the arm including a pivot having a surface wherein the pivot is interfit against the surfaces such that the pen latch can be rotatably moved between an open position and the closed position and the interfit provides y-axis, z-axis, theta-y and theta-z constraints for printheads of each pen.
29. The assembly as set forth in claim 23, comprising:
each of the interfit devices includes a pen latch retainer on the carriage, the retainer including wedge-configured receivers having receiver mating surfaces for providing x-axis constraint, and a protruding arm on the pen latch, the arm including at least one face having a geometric configuration for establishing a interfit against at least one of the receiver mating surfaces such that in the closed position, the interfit provides x-axis and z-axis constraints for pen printheads.
30. The assembly as set forth in claim 23, comprising:
each of the interfit devices includes at least one wedge-configured receiver positioned on the carriage in a region proximate the biased handle receiver, the receiver having a mating surface for providing y-axis constraint, and the pen latch having at least one surface having a face having a geometric configuration for establishing a interfit against the mating surface when the pen latch is in the closed position such that the interfit provides y-axis, z-axis, theta-x, and theta-z constraints of pen printheads.
31. The assembly as set forth in claim 23, comprising:
the carriage means and pen latch means complementary interfit devices provide pen pitch, pen roll and pen yaw counterforces when the pen latch means is in the closed position.
32. The assembly as set forth in claim 29, comprising:
the interfit surfaces are provided with surface angles wherein the contact between the surfaces is self-locking.
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 zoom lens comprising, in order from an object side to an image side of said zoom lens:
a first lens unit having positive optical power;
a second lens unit having negative optical power;
a third lens unit which has positive optical power and which does not move for zooming; and
a fourth lens unit having positive optical power,
wherein when zooming from a wide-angle end to a telephoto end, the first lens unit is moved toward the object side and the second lens unit is moved toward the image side, whereby the distance between the first and second lens units is increased, and
wherein, when fW and fT are focal lengths of the overall system at the wide-angle end and the telephoto end, respectively, f2 is a focal length of the second lens unit, e3T is the distance between principal points of the third and fourth lens units at the telephoto end when an object located at infinity is in focus, f3 and f4 are focal lengths of the third and fourth lens units, respectively, and fA is defined as fA{square root}{square root over (fwfT)}, at least one of the following expressions is satisfied:
0.17<f2fA<0.30,2.05<e3TfW<2.96,
and
0.6<f3f4<0.92.
2. A zoom lens according to claim 1, wherein at least one of the following expressions is satisfied:
0.20<f2fA<0.28,2.10<e3TfW<2.80,
and
0.65<f3f4<0.90.
3. A zoom lens according to claim 1, wherein at least two of the conditions are satisfied.
4. A zoom lens according to claim 1, wherein all three of the conditions are satisfied.
5. A zoom lens according to according to claim 1, wherein the fourth lens unit is moved during zooming and focusing.
6. A zoom lens according to according to claim 5, wherein the fourth lens unit is moved along a locus which is convex toward the object side in zooming from the wide-angle end to the telephoto end.
7. A zoom lens according to according to claim 1, wherein, when e3W is the distance between the principal points of the third and fourth lens units at the wide-angle end when the object located at infinity is in focus, and M2 is the amount by which the second lens unit is moved in zooming from the wide-angle end to the telephoto end, the following expression is satisfied:
(e3Te3W)M2<0.13.
8. A zoom lens according to according to claim 1, wherein, when e3W is the distance between the principal points of the third and fourth lens units at the wide-angle end when the object located at infinity is in focus, and M2 is the amount by which the second lens unit is moved in zooming from the wide-angle end to the telephoto end, the following expression is satisfied:
(e3Te3W)M2<0.11.
9. A zoom lens according to according to claim 1, wherein when 2W and 2T are lateral magnifications of the second lens unit at the wide-angle end and at the telephoto end, respectively, and Z is the zoom ratio of the overall system, where ZfTfW, the following expression is satisfied:
0.95<Log(2T2W)Log(Z)<1.24.
10. A zoom lens according to according to claim 1, wherein when 2W and 2T are lateral magnifications of the second lens unit at the wide-angle end and at the telephoto end, respectively, and Z is the zoom ratio of the overall system, where ZfTfW, the following expression is satisfied:
0.95<Log(2T2W)Log(Z)<1.15.
11. A zoom lens according to claim 1, wherein the third lens unit comprises:
at least one positive lens; and
a negative lens having a concave surface which has a higher optical power in the direction toward the image side than in the direction toward the object side, the concave surface facing toward the image side.
12. A zoom lens according to claim 1, further comprising an aperture stop located next to the third lens unit, on the object side, wherein the aperture stop does not move during zooming.
13. A zoom lens according to according to claim 1, wherein when M1 is the amount by which the first lens unit is moved in zooming from the wide-angle end to the telephoto end and M2 is the amount by which the second lens unit is moved in zooming from the wide-angle end to the telephoto end, the following expression is satisfied:
0.7<M1M2<1.4.
14. A zoom lens according to according to claim 1, wherein when M1 is the amount by which the first lens unit is moved in zooming from the wide-angle end to the telephoto end and M2 is the amount by which the second lens unit is moved in zooming from the wide-angle end to the telephoto end, the following expression is satisfied:
0.85<M1M2<1.25.
15. A zoom lens according to according to claim 1, wherein when R2i is the radius of curvature of an ith surface in the second lens unit counted from the object side, the radius of curvature being the paraxial radius of curvature when the surface is aspherical, the following expression is satisfied:
0.65<R22R23<0.79.
16. A zoom lens according to according to claim 1, wherein when R2i is the radius of curvature of an ith surface in the second lens unit counted from the object side, the radius of curvature being the paraxial radius of curvature when the surface is aspherical, the following expression is satisfied:
0.7<R22R23<0.78.
17. A zoom lens according to claim 1, where at least a part of the third lens unit is moved in a direction perpendicular to an optical axis so that an image formed by the zoom lens is also moved.
18. A zoom lens according to claim 1, where the zoom lens forms an image on a photoelectric transducer.
19. A camera comprising:
a zoom lens, said zoom lens comprising, in order from an object side to an image side of said zoom lens:
a first lens unit having positive optical power;
a second lens unit having negative optical power;
a third lens unit which has positive optical power and which does not move for zooming; and
a fourth lens unit having positive optical power,
wherein when zooming from a wide-angle end to a telephoto end, the first lens unit is moved toward the object side and the second lens unit is moved toward the image side, whereby the distance between the first and second lens units is increased, and
wherein, when fW and fT are focal lengths of the overall system at the wide-angle end and the telephoto end, respectively, f2 is a focal length of the second lens unit, e3T is the distance between principal points of the third and fourth lens units at the telephoto end when an object located at infinity is in focus, f3 and f4 are focal lengths of the third and fourth lens units, respectively, and fA is defined as fA{square root}{square root over (fwfT)}, at least one of the following expressions is satisfied:
0.17<f2fA<0.30,2.05<e3TfW<2.96,
and
0.6<f3f4<0.92;
and
a photoelectric transducer that receives an image formed by said zoom lens.
20. A camera according to claim 19, wherein at least one of the following expressions is satisfied:
0.20<f2fA<0.28,2.10<e3TfW<2.80,
and
0.65<f3f4<0.90.