FR2461275A1 - PHOTOGRAPHIC CAMERA WITH LENS COVER - Google Patents

Abstract

THE INVENTION CONCERNS A PHOTOGRAPHIC APPARATUS 1 INCLUDING A LENS 7 MOBILE IN THE DIRECTION OF ITS OPTICAL AXIS IN RESPONSE TO THE OPERATION OF A DISTANCE ADJUSTMENT RING 9, AND A LENS COVER 9 MOBILE BETWEEN A FIRST POSITION IN WHICH IT COVERS L 'BEFORE THE LENS AND A SECOND POSITION IN WHICH HE DISCOVERED THIS. TRANSMITTER ORGANS 14, 15 PLACES ON THE DISTANCE ADJUSTMENT RING, ARE DRIVEN BY DRIVING ORGANS 16, 17 MOUNTED ON THE LENS COVER TO CAUSE ANGULAR MOVEMENT OF THE DISTANCE ADJUSTMENT RING UNTIL THE THE LENS REACHES ITS NORMAL FOCUS POSITION WHEN THE LENS COVER GETS ITS FIRST POSITION. THE DEVICE ALLOWS IMMEDIATE SNAPSHOTS TO BE TAKEN WITHOUT PRIOR SETTING.

Description

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  The present invention relates to a photographic camera equipped with a protective lens cover and, more specifically, such a device whose lens cover can move between a first position in which it covers the front of the lens. -

  tif of shooting and a second position in the-

what it releases this objective.

  Several lens cover devices have been proposed

capable of covering the front of a susceptible lens

ble of axial displacements on its optical axis for the

focus.

  Devices of this kind are suitable for portable cameras and have advantages

  for snapshots. In such cases, it is often

  haitable to be able to immediately activate the camera regardless of the distance from the object photographed

Specifically, when photographing an immobile object

bile, the shutter function may be de-

snapped after having made a precise development but, for moving objects, we risk leaving

  to pass the optimal moment of operation of the obtu-

erator, while we are focusing, allowing the object to be photographed at a given moment It is therefore desirable to minimize the time

required for focusing.

On the other hand, a lens has a depth of field determined by the focal length of the lens, the aperture of the diaphragm and the distance from the photographed object (to which the focus adapts)

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The depth of field represents a region in the-

  what the image of an object, despite a focus

  imperfect, appears clearly to the human eye.

For example, if you choose a diaphragm aperture of f-8 for a 35mm focal length lens, the depth of field will be

  an area ranging from approximately 2.5 m to the interior

  finished if the distance of the photographed object is fixed at 5 m. If the distance is set to 3 m, the depth of field will be approximately between 1.8 m and 8 m * In other words, when the objective of

  shooting in question is used with an open

f-8 diaphragm size, it is possible to take fairly satisfactory photographs of most

  objects if the device has a deep ring

  deur de champ set to a position corresponding to a

  distance approximately between 3 and 5 m.

If this parameter varies with the distance for which the lens is focused, it is known that there is, for each lens, a focusing distance, called normal focus position, suitable

  most of the objects.

  Consequently, in the case of a camera

phique equipped with a lens cover, it is desirable that the lens of the camera is placed in position

normal focus each time the cover

  lens opens in order to be able to photograph immediately

most of the objects.

The authors of this Patent Application have pro-

  installed a lens translating device for

  photographic reil with lens cover (Patent

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  United States of America NQ 4,171,894; Patent application

  German P 29 01 991.3) in which, when the object

tif is moved forward to the point of projecting beyond the lens cover to photograph a very close object, this lens can return to a position corresponding to infinity or to its normal focus position when the lens cover wins

the device's non-use position. This dis-

positive reduces the height of the sail-

  lante of the objective to a value corresponding to the maximum retraction of the objective, therefore to reduce the thickness from front to back of the camera However, if it is admitted that the objective must occupy its position of setting at normal point in order to be able to photograph most objects as soon as the lens cover is opened, it is desirable that, each time the lens cover is reopened, the lens returns to its normal focus position (s '' it retracted below this) or even comes to occupy a position corresponding to infinity if we

  must photograph an object located at infinity.

  In view of the above, the object of the present invention is to provide a camera

  photographic fitted with a lens cover in the-

  which, each time the lens cover moves to gain a first position in which it

  covers the lens when the camera is not in use, the-

said lens moves either backwards or forwards from a position corresponding to infinity or its nearer punctum in order to occupy its normal focus position when the lens cover

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has reached the position in which it covers

the goal.

  In accordance with the invention, the objective gains its position

normal focusing in synchronism with the movement of the lens cover to the position in which it covers the front of the lens when the camera is not in use. Therefore, when

  opens the lens cover for the next shot

  te, the lens is already in its normal focus position to match the minimum focus for shooting most

  objects without having to focus.

In this way, the camera makes it possible to photograph a rapidly moving object without letting the critical moment pass for the shutter. According to another of its aspects, the invention aims to produce a photographic camera that is easy to actuate by a inexperienced beginner. focus, since it allows you to take pictures without having to focus

The invention is described below in detail in detail.

referring to two preferred, nonlimiting examples of embodiment shown in the accompanying drawings in which: - Figure 1 is a perspective view of an apparatus

  photographic according to the invention, including the cover

  obj-ctif is-placed so as to cover the objective - Figure 2 is a perspective view of the apparatus of Figure 1 when the lens cover discovers the objective;

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  - Figure 3 is a front view of the apparatus of the

  figure 2, when the lens cover discovers the

and that the latter is adjusted to a shooting position centered on an object situated beyond (that is to say more distant) from the normal focus position;

- Figure 4 is a view similar to that of the fi-

gure 3, showing the conditions existing when the lens cover discovers the lens and the latter is adjusted to a shooting position centered on an object located below (i.e. closer) to the focus position at normal point; - Figure 5 is a front view of the apparatus of Figure 1 when the lens cover (shown in

  skinned part) is placed so as to cover the ob-

  jective; - Figure 6 is a front view of the apparatus of Figures 1 and 2, when the lens cover passes from its first position, in which it covers the lens, to its second position, in which it discovers the latter;

  - Figure 7 is a front view of a camera

  tographic according to a second embodiment of the invention, when the lens cover is placed so as to uncover the lens and that the latter is adjusted to a shooting position centered on an object situated below the focusing position at normal point; - Figure 8 is a front view of the apparatus of Figure 7, when the lens cover is placed so as to uncover the lens and that the latter is adjusted to a shooting position centered on an object located beyond the focus position

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  normal point; and - Figure 9 is a front view of the apparatus of Figure 7 when the lens cover (shown in

skinned part) is placed so as to cover the ob-

  jective. Figures 1 and 2 show a photographic camera 1 equipped with a sliding protective lens cover 2 constructed according to a first embodiment of the invention. In Figure 1, the lens cover 2 is shown in its first position in which it covers the front part

of the lens, while in Figure 2 it is re-

  presented in his second position in which he

discovers this objective 7.

  As shown in the figures, the lens cover 2

partially covers the front face, the

  lb and the rear side 1 of the camera 1 and has, in the center of its front part, a trapezoidal cap 2a projecting at a height corresponding to the projection of the lens 7. This lens cover 2 is placed so to be able to move in a direction perpendicular to the optical axis of the objective while being guided by slides not shown, between its first position in which it covers the front of the objective 7 and its second position in which it discovers this last. When the lens cover 2 has been brought to its first position in which it

  covers objective 7, it also covers fe-

  viewfinder 4 and the shutter button 5. When-

this lens cover 2 slides in second position,

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  in which it discovers the objective 7, it covers a film winding button 6 placed on the upper face 1b of the camera 1 and serving at the same time

  lock to a flap on the rear side of the latter

deny (figure 2)

The objective 7 is carried by a barrel 8 placed at the center

be from the front part of the device 1 At its front part, the barrel 8 comprises a distance adjustment ring 9 made in one piece with it At its rear part (not visible) this barrel has a thread

well-known helical that can be screwed into a tarau-

complementary helical beam formed in the body of the camera 1, so that the objective 7 is carried so as to be able to move in the direction of its optical axis. By turning the distance adjusting ring 9 in one direction or the other, you can

advance or retract objective 9 on its op axis

  tick to focus The distance adjustment ring 9 has an operating lug 10 which can be moved

  angular with a finger to produce the same movement

  ment in the adjusting ring 9. On its front face, the adjusting ring 9 has a graduation indicating

  the distances from 0.5 m to infinity and can be a-

  carried out opposite an index 13 engraved on the body of the device 1. At its outer periphery (invisible from

  the outside) the ring 9 has a notch 9a (fig.

re 3) limiting the extent of the angular movement of the ring by the coming into contact of one or the other end of the notch with a locking pin 12 fixed to the body of the device 1. In rotating the distance adjusting ring 9 within the limits thus fixed, it is possible to bring up to

  index 13 any indication of the gradua-

  tion 11 from 0.5 m to infinity and thus adjust the pro-

objective 7 field founder from his punctum

proximum (0.5 m) to infinity.

In accordance with the invention, a first organ trans-

  director 14, in the form of a protruding pin, is fixed to the front face of the adjustment ring of

  distances 9 at the height of the indication "5 m" from the gra-

  duation 11 or aligned with a normal focusing position of the lens 7 so as not to obscure this indication. A second transmitting member 15, also constituted by a protruding pin, is placed on the front face of the ring for adjusting the

  distances 9 at a point diametrically opposite the first

  mier transmitting member 14. Consequently, when the ring 9 is rotated so that the indication "5 m" of the scale 11 is opposite the index 11, the first and second transmitting members 14 and 15

  will find on a line parallel to the vertical edges

cals 2b of the lens cover 2.

  If we now refer to Figures 3 and 4, we

  sees a first organ- coach 16 and a second or-

  gane coach 17, both made of elastic blades

  ques, fixed to the internal face of the cap 2a of the lens cover 2 by rivets 18 so as to be located in the same plane as the first and second members

  transmitters 14 and 15. Each of these organs en-

markers 16 and 17 have a notch 16b or 17b

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parallel to the vertical edge 2b, transforming the part of the driving member 16 or 17 closest to the edge 2b into a tongue 16a or 17a parallel to said edge 2b

and being able to engage with the corresponding transmitting member

respondent 14 or 15 and train it. When the lens cover 2 has gained its first position in which it covers the lens 7, these tabs drive the transmitting members 14 and 15 and cause a

angular movement of the adjustment ring

tances 9.

  When we want to take a photograph, we do

  edge slide the lens cover 2 into position

  shown in Figures 2 and 3 where he discovers the object

  tif 7. By sliding, the lens cover uncovers the window 4 of the viewfinder and the release button 5, but covers the winding button 6 to prevent the rear flap from opening. We can then do

  turn the operating pin 10 so as to

  write an angular movement to the distance adjusting ring 9 and, once the focus is achieved,

you can press the trigger button 5 to take

  dre photography. Assuming that the adjustment ring

ge of distances 9 is set to a position beyond the normal focus position "5 m" from lens 7, for example at a position where the sign "q Q" W of infinity is at height of the index 13, one of the transmitting members 14 or 15, in this case the first transmitting member 14, is placed near

  of the tongue 16a of the first driving member cor-

  respondent 16, as shown in Figure 3. By cons

tre, if the adjusting ring 9 is adjusted at a distance less than the normal focus position, by

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  example at the distance of "0.5 m", this is the second or-

  gane transmitter 15 which will be placed near the

  tongue 17a of the second corresponding driving member

in 17, as shown in Figure 4.

So when the lens cover 2 is brought to its first position in which it covers the lens 7

  after taking a photograph, one of the

lookouts 16a or 17a will engage with, and push, one or the other of the first and second transmitting organs

  14 or 15. Specifically, when you close the cover

lens 2, the distance adjustment ring 9

  is forced to turn, either clockwise

watch faces either in the opposite direction and, once the movement of the lens cover 2 has been completed to cover the lens 7, the two tongues 16a and 17a

will touch the transmitting organs 14 and 15, respectively

tively. It should be noted that when the cover

  objective 2 has completely reached the position in

  which it covers objective 7, it would be necessary

  ensure that there is perfect and close contact between the transmitting members 14, 15 and the tongues 16a, 17a but the inherent elasticity of the latter, resulting from the prezence of the notches 16b, 17b, allows

compensate for slight differences in dimensions

  be the transmitting organs 14, 15 and the organs

coaches 16, 17 when in contact.

When the tongues 16a and 17a of the driving members

  nors 16 and 17 come to touch the organs transmits-

  ters 14 and 15, respectively, the latter are

wind placed on a line parallel to the edges 2b of the

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  lens cover 2, as mentioned above, and now-

  hold lens 7 in focus position

normal. So we see that when we open the cover

  described lens 2, lens 7 occupies its normal focusing position, as shown in FIG. 6. Under these conditions, the camera is therefore in advance in a position to allow photographing with minimal clarity without requiring other focus, so

to take snapshots.

Figures 7, 8 and 9 show a camera-

  graphic 21 fitted with a lens cover 2 constructed according to a second embodiment of the invention

  In these figures 7, 8 and 9, the elements corresponding to

Dant elements of Figures 1 to 6 bear the same reference numbers. In this second embodiment, a single transmitting member 22 is fixed on the distance adjusting ring 9 at a point covered by the lens cover 2 when the latter

  is open. A driving member 23, in the form of a plate

  cam plate, is fixed to the internal face of the cap 2a of the lens cover 2 by rivets 24. The side of the driving member 23 facing the transmitting member 22 has an asymmetrical V-shaped notch forming an upper cam path 23a and a lower cam path 23b As can be seen in FIG. 7, the first cam path 23a of the driving member 23 will be close to the transmitting member 22 when the distance adjusting ring 9 is set to a distance lower than the normal focus position, for example on a punctum proximum "0.5 m" from the graduation of distances 11, while

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it will be the second cam path 23b which will be close to this driving member 22 if the ring 9 is adjusted by a distance greater than the normal focus position, for example on the infinity sign "oQ" of the graduation 11, as shown in FIG. 9 A bearing 23c, separating the two cam paths 23a and 23b, is placed at a height such that it is opposite the transmitting member 22 when the adjustment ring of the distances 9 is set to its position of

normal focus.

  When after taking a picture cover it

  objective 2 comes to cover objective 7, it entranne with it the driving member 23 of which one of the cam tracks 23a or 23b comes to touch the transmitting member 22 and push it. The distance adjusting ring 9, which is integral with the transmitting member 22, is

  therefore forced to turn, either in the direction of-ai-

watch faces is in the opposite direction, until the bearing 23c at the bottom of the notch of the driving member 23 comes to touch the transmitting member 22 to place the lens 7 in the focusing position

  normal when lens cover 2 has gained its pre-

best position, as shown in figure 9

  We see that, in this second embodiment, the an-

  25. device 9 for adjusting the distances 9 requires only a single transmitting member 22 which remains hidden under the lens cover 2 when the latter discovers the lens 7 whose appearance is thus sharper

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In the two embodiments described, the organizations

  nes coaches 16 and 17 of device 1, or the organ

  driver 23 of the device 21 are parts available

  lens cover 2, but it should be understood

that these driving bodies can be made

  in one piece with the lens cover.

Claims (6)

1. Photographic camera equipped with a lens cover slidably mounted on the external part of the camera body so as to be able   move between a first position in which   it covers the front face of the objective and a second position in which it discovers said objective, characterized in that it comprises   - a distance adjustment ring arranged in a   lesson in being able to describe an angular movement on the optical axis of the objective in order to cause the displacement of said objective in the direction of said optical axis in order to carry out a focusing.   - a transmitting member fixed on the ring of re- setting distances; and - a driving member on the lens cover to produce an angular movement of the distance adjustment ring via the transmitter member until the lens reaches its normal focus position   when the lens cover wins its first po- sition in which it covers the lens 2. Photographic camera according to   Claim 1, characterized in that it comprises carries two transmitting members diametrically opposite one another on a diametrical line of the objective. 246 1275   3. Photographic camera according to   Claim 1, characterized in that it comprises   carries two driving bodies made of material   elastic and attached to the inside of the cover   objective so as to oppose the transmitting organs. 4. Photographic camera according to Claim 3, characterized in that each entraining member is partially notched so that its part closest to the member transmitter forms an elastic tongue.   5. Photographic camera according to Claim 1, characterized in that it comprises   carries a single transmitting member arranged so as to be hidden under the lens cover when the latter occupies its second position in which he discovers the objective.   6. Photographic camera according to claim 1, characterized in that the side of the driving member facing the transmitting member has an asymmetrical notch in V defining two cam paths making contact with the transmitting member and training him every after the lens is placed in a different position from the normal focus position, a intermediate bearing at the two camways ve-   touching the transmitting organ when the   vre-Objectif reaches its first position in the- what it covers the objective