Photography – With exposure objective focusing means – focusing aid – or... – Mechanical mechanism for displacement of exposure objective
Reexamination Certificate
2002-05-22
2004-03-02
Adams, Russell (Department: 2851)
Photography
With exposure objective focusing means, focusing aid, or...
Mechanical mechanism for displacement of exposure objective
C396S132000, C396S133000
Reexamination Certificate
active
06701076
ABSTRACT:
BACKGROUND OF INVENTION
1. Field of the Invention
The present invention relates to a focus retaining mechanism, and more particularly, to a focus retaining mechanism of a camera.
2. Description of the Prior Art
Please refer to
FIG. 1
of a top view of a conventional lens driving device
10
of a camera. The lens driving device
10
is disclosed in U.S. Pat. No. 5,680,649 “LENS DRIVING DEVICE FOR AUTO-FOCUS CAMERA”. The lens driving device
10
comprises a base
12
comprising a cylindrical opening
16
, a focusing lens
14
rotatably mounted within the opening
16
, a lens setting ring
40
rotatably mounted on the periphery of the opening
16
on the base
12
, a driving ring
44
mounted on the base
12
by hooking the lens setting ring
40
, a cam portion
42
, a lens barrel
18
mounted on the base
12
by hooking the lens setting ring
40
and the cam portion
42
, a first bi-directional driving motor
20
and a second bidirectional driving motor
30
mounted on the base
12
, a spring
34
mounted on the base
12
, and a retainer member
22
disposed on the base
12
. In addition, a cylindrical projection
46
disposed on the lens setting ring
40
hooks an engaging portion
19
of the lens barrel
18
. Thus, when the lens setting ring
40
is rotated, the lens barrel
18
and the focusing lens
14
are also rotated. The second bidirectional driving motor
30
is used to rotate the driving ring
44
for controlling a shutter. The first bi-directional driving motor
20
is used to drive the retainer member
22
for mounting the cam portion
42
in a predetermined position so as to rotate the focusing lens
14
to a corresponded position. Moreover, an idler gear
70
and a first ratchet
50
are used for the transmission between the cam portion
42
and the retainer member
22
.
As shown in
FIG. 1
, when the second bi-directional driving motor rotates the driving ring
44
toward a positive direction via a second ratchet
32
to control an opening position of the shutter, the driving ring
44
moves the lens setting ring
40
so as to rotate the lens barrel
18
and focusing lens
14
. At the same time, the lens setting ring
40
also moves the retaining member
22
so that a plurality of gear portions
43
hook with a hold lever
60
one by one. The retaining member
22
rotates the first ratchet
50
by hooking the idler gear
70
.
When the second bi-directional driving motor
30
moves the driving ring
44
toward a positive direction to a predetermined position, which is an appropriate position for focusing, the first bi-directional driving motor
20
controls the retainer member
22
to stop rotating the first ratchet
50
. At this time, a pull-back action to the retaining member
22
generated by the flexible component
34
is stopped due to the stop action of the retainer member
22
. Thus, the lens barrel
19
and the driving ring
44
do not circumrotate so that the lens driving device
10
can focus and retain position. At this time, the driving ring
44
moves to a predetermined shutter position and opens the shutter, and the lens barrel
18
also drives the focusing lens
14
to rotate to a corresponding position.
The second bi-directional driving motor
30
continues to rotate in a positive direction and moves the driving ring
44
to an utmost position
45
. At the same time, the first bi-directional driving motor
20
drives the retainer member
22
to rotate the first ratchet
50
so that the first ratchet
50
and the cam portion
42
rotate to corresponding utmost positions. At this time, the second bi-directional driving motor
30
provides no power to the lens driving device
10
. That means after the second bi-directional driving motor
30
moves the driving ring
44
to a utmost position
45
, only the first bi-directional driving motor
20
provides a small amount of power to back focus retaining structures such as the first ratchet
50
, the cam portion
42
, the lens barrel
18
, the driving ring
44
, and the flexible component
14
to an initial state. After the first bi-directional driving motor
20
drives the retainer member
22
and the first ratchet
50
to their utmost positions, the first ratchet
50
does not contact with the retainer member
22
, and a spring
62
disposed on the base
12
pulls the hold lever
60
back to the initial state. This is an action of closing the shutter. In addition, the flexible component
34
also pulls the cam portion
42
back to the initial state so that the driving ring
44
, lens barrel
18
, and the first ratchet
50
are also moved back to the initial states.
As described above, the conventional lens driving device
10
has a complicated focus retaining structure, and a retainer member and a gear assembly are needed. Thus, the complexity and costs of components are increased. This highly complicated structure hardly reduces costs of assembly. In addition, although the retainer member
22
acts effectively, the available space of the lens driving device
10
is decreased with the use of the retainer member
22
.
SUMMARY OF INVENTION
It is therefore a primary objective of the claimed invention to provide a focus retaining mechanism to solve the above-mentioned problems.
The claimed invention provides a focus retaining mechanism of a camera. The camera comprises a base, a focusing lens, a retaining member, and a retaining hook. The base comprises a cylindrical and vertical opening therein. The focusing lens is rotationally fixed within the opening. The retaining member is horizontally and movably fixed in the base. The horizontal sides of the retaining member include a ratchet side, a smooth side, a first end and a second end positioned over the connecting portions of the ratchet side and the smooth side. The retaining hook has a horizontal arm and a vertical arm installed under the horizontal arm. The horizontal arm can move horizontally across the upper side of the retaining member, and the vertical arm can thus contact each of the horizontal sides of the retaining member.
It is an advantage of the claimed invention that a focus retaining mechanism of a camera with a simple design is used for simplifying the focus retaining mechanism
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment, which is illustrated in the various figures and drawings.
REFERENCES:
patent: 4985724 (1991-01-01), Akimoto et al.
patent: 5680649 (1997-10-01), Akimoto et al.
patent: 5710949 (1998-01-01), Akimoto et al.
Adams Russell
Hsu Winston
Primax Electronics Ltd.
Smith Arthur A
LandOfFree
Camera with a focus retaining mechanism does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Camera with a focus retaining mechanism, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Camera with a focus retaining mechanism will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3257463