GB2031169A - Motorised camera - Google Patents

Abstract

In a motorised camera employing spring-biased reciprocatory rod 40, depression of button 2 causes anticlockwise rotation of lever 61 against a spring bias to release projecting tongue 40c of rod 40 for movement to the left from the position shown, multiple exposure by prolonged depression of button 2 being prevented by means of anticlockwise spring-biased lever 62 which retains tongue 40c to the right of the position shown until button 2 is released and lever 61 (having a stronger spring than lever 62) is allowed to rotate clockwise. Lever 62 may be overridden (for multiple exposure) by raising push button 66. The camera is of the type in which depression of button 2 closes switch 18 and releases rod 40 to operate shutter 24 (and close switch 19) and close switch 21/22 thereby commencing operation of motor 16 (continued by centrifugal closing of switch 20) to return rod 40 to the charged position and advance the film to the next perforation (switch 22/23 then being closed to short circuit motor 16 and rod 40 freed from lever 46). <IMAGE>

Description

SPECIFICATION A still photographic camera This invention relates to a still photographic camera of the kind including a shutter, a reciprocable member which is arranged to prime the shutter when moved in one direction to a first position and to release the shutter on movement in the opposite direction into a second position, means biasing the reciprocable member in the opposite direction, latch means arranged to hold the reciprocable member out of said second position against the action of the biasing means and operable to release said member upon actuation of a shutter release member, an electric motor operable to wind on a film loaded in the camera in use, means operable after a film winding-on operation to open a switch in a power supply circuit of the motor, and means operable to drivingly couple the reciprocable member with the electric motor for movement by the motor in said one direction, the reciprocable member becoming operatively disengaged from the motor when reaching said first position.

A camera of the kind specified has already been proposed and has the facility that a plurality of exposures can be made consecutively by maintaining the shutter release member in its actuated condition for the duration of the exposures. However, the proposed camera suffers from the disadvantage that when a camera user attempts to make a single exposure, if the shutter release member is accidentally actuated for an excessively long time, a sequence of two or more exposures may result. An object of the present invention is therefore to alleviate or minimise this disadvantage.

Accordingly, the invention resides in a still photographic camera including a shutter, a reciprocable member which is arranged to prime the shutter when moved in one direction to a first position and to release the shutter on movement in the opposite direction into a second position, means biasing the reciprocable member in the opposite direction, latch means arranged to hold the reciprocable member out of said second position against the action of the biasing means and operable to release said member upon actuation of a shutter release member, an electric motor operable to wind on a film loaded in the camera in use, means operable after a film winding-on operation to open a switch on a power supply circuit of the motor, and means operable to drivingly couple the reciprocable member with the electric motor for movement by the motor in said one direction, the reciprocable member becoming operatively disengaged from the motor when reaching said first position, wherein the latch means includes first and second release levers which are biased in opposite directions by respective springs such that in a rest position the first lever is held by its respective spring in the path of movement of the reciprocable member in said opposite direction, while the second lever is held out of the path of said movement of the reciprocable member, the first lever being movable out of its rest position to release the reciprocable member upon actuation of the shutter release member, and the second lever being movable into the path of movement of reciprocable member after actuation of the shutter release mem ber and movement of the reciprocable member to its first position and then to its second position.

The accompanying drawing is an exploded pers pective view, not to scale, of a camera according to one example of the present invention.

Referring to the drawing, the camera shown is adapted to receive a film cassette 8 having a storage compartment from which a film 7 can be progres sively transported across an exposure window and into a winding compartment where the film is wound onto a take-up spool. Formed in the film are a plurality of longitudinally spaced perforations 7a (only one shown), one perforation being provided for each exposure to be made on the film.

The camera includes a housing 1, only part of which is shown forthe sake of simplicity, and a shutter release button 2 which is mounted in one wall of the housing. The button 2 is movable into the housing in the direction of the arrow 3 to pivot a two-armed release lever 6b in an anti-clockwise direction about an axis 4 and against the action of a spring 5, the lever 6b extending parallel with the transport direction of the film. The lever 6b defines the operating member of an electrical switch 18 which is arranged to be closed by the lever arm 6b when the button 2 is moved in the direction of the arrow 3. Actuation of button 2 also serves to move a control slider 6a in the direction of arrow 3 against one arm 61a of a two-armed lever 61.The lever 61 is thereby pivoted about an axis 60 in an anti-clockwise direction as shown in the drawing and against the action of a relatively strong spring 63. Also mounted for pivotal movement about the axis 60 is a further two-armed lever 62 which has one arm 62a spaced in front of the arm 61 a out of contact with the slider 6a and its other arm 62b located beneath the arm 61 d.

Moreover, the arm 62b is longer than the arm 61b.

Located within the housing 1 between the stop 1a and a control cam 1b is a detector lever 9 which, in the position shown, engages in one of the perforations 7a in the film 7. The lever 9 is biased towards the film 7 by a spring 10 and towards the stop 1a by a further spring 11. In the position shown the lever 9 is held in engagement with the control cam 1b against the action of the spring 11. The lever 9 is formed with a longitudinally extending slot 9a and with an arm Sb which extends perpendicular to the operating direction of the springs 10, 11 into the path of movement of one arm 1 2a of a three-armed control lever 12. The lever 12 is pivotable about an axis 13 and has a second, short arm 12b formed with a peg 12e which engages in a slot 14a formed in one arm of a two-armed lever 14.The lever 14 is movable angularly about an axis 15 and defines a control edge 14b at the free end of its other arm. The third, relatively long arm 12b of the control lever is generally L-shaped and is formed with a bore 12g in one limb, a peg 12fatthe junction between the limbs and a peg 12e at the free end of its other limb. The lever 12 is arranged so that its major dimension defined by the arms 12a, 12b extends parallel with the transport direction of the film 7.

Transport of the film 7 is effected by an electric motor 16 which is located directly in front of the region of the camera which, in use, receives the winding compartment of the cassette 8. To power the motor 16 are two torch batteries 17 which are located adjacent the region of the camera which in use receive the storage compartment of the cassette 8 and which extend generally parallel with the optical axis of the camera shutter 24. Electrically connected in series between the batteries 17 and one terminal of the motor 16 are the switch 18 and a second switch 19, with a third switch 20 being connected in parallel with the switches 18, 19.

Connected between the batteries 17 and the other terminal of the motor 16 is a fourth switch 21,22, having its movable contact 22 common with a fifth switch 22, 23 operable to short circuit the motor 16.

The contact 22 is resiliently urged to close the switch 21,22 but is movable by the peg 12e in a direction to open the switch 21, 22 and close the switch 22, 23.

The contacts of the switch 19 are arranged so as to lie in the path of a peg 24a movable with the camera shutter 24 such that the switch 19 is closed at or near one end of the shutter operation. Priming of the shutter 24 is effected by a pinion 24b which is in meshing engagement with a rack 40e defined by a connected rod 40 and which operates by way of a one-way coupling (not shown) so as to be rotatable in a clockwise direction to prime the shutter and to be freely rotatable in the opposite direction. Release of the shutter is controlled in the manner described below by a peg 24c provided on the shutter 24 and an arm 40d projecting from the connecting rod 40.

The motor 16 drives a pinion 16a under the control of a brake lever 25. The brake lever 25 includes a peg 25a which engages in the bore 1 2g of the control lever 12 such that, according to the position of the control lever 12, the brake lever 25 is engageable with the pinion 16ato lockthe pinion. Drivingly coupled with the pinion 16a is a reduction gear 26 including a gearwheel 26a which meshes with a further gear wheel 27. The gear wheel 27 in turn meshes with a gear wheel 28 of a centrifugal switch 29 including an operating peg 29a which maintains the switch 20 closed while the motor 16 is running. It is to be appreciated that, in order to more clearly explain the operation of the camera, the gear wheel 28 is shown twice in the drawing.

Rigidly connected to the gear wheel 27 is a gear wheel 30 which meshes with a large diameter gear wheel 31 which in turn has a further gear wheel 32 rigidly connected thereto. The gear wheel 32 meshes with a gear wheel 33 which is coupled by way of a gear wheel 34 to a further gear wheel 35 which is drivingly connected to the take-up spool of the film cassette. All the gear wheels consist of thin metal or piastic, generally planar toothed wheels so that the entire gearwheel drive measures only a few mil limetres in height.

Engageable with the gear wheel 27 is a gear segment 37 which is rigidly mounted on a rotatable shaft 36 together with a cam disc 38 such that, depending on the angular position of the cam disc 38, the gear segment 37 can mesh with the gear wheel 27 to be driven by the gear wheel 27. Pivotally connected to the cam disc 38 by a pin 39 is a connecting rod 40 which includes a control peg 40a and a shoulder 40b, a projecting tongue 40c as well as the arm 40d, and tie rack 40e. The connecting rod 40 extends parallel with the transport direction of the film 7 and a spring 41 biases the connecting rod 40 to the left, as viewed in the drawing, i.e. in the opposite direction to that required for priming the shutter.

The peg 12f of the lever 12 is slidably received in a slot 42a formed in one arm of a further 3-armed lever 42 having a curved second arm 42b located in the path of movement of the peg 40a. The third arm of the lever 42 defines a retaining edge 42c and is urged against a top Ic by a spring 43 which also urges a locking egde 44a of a further lever 44 towards the third arm of the lever 42. The lever 44 is pivotable about a shaft 45 and the free end 44b of the lever 44 is urged by the spring 43 against one end ofthe connecting rod 40. Afurther lever 46 is pivotally mounted on a shaft 47 and is urged by a spring 48 towards the lever 14 and the connecting rod 40 so as to be engageable with either the control edge 14b or the shoulder 40b.The levers 12,44,46,42 are arranged so that together they extend mainly parallel with the fi.m transport direction. Moreover, the control means defined by the levers 12,9,42,44 and the rod 40 is of overall height less than or equal to the overall height of the gear wheel drived defined by the pinion 1 6a and the gear wheels 26 to 38.

In order to understand operation of the camera described above, it is to be appreciated that the camera is shown in the drawing with the shutter 24 primed and the film 7 at the end of its movement necessary to allow a new exposure to be taken. In this position, the switches 18, 19,20 and 21 are all open and the movable contact 22 is urged by the peg 1 2e to close the switch 22, 23 so that the motor 16 is short circuited. In addition, the arm 61b of the lever 61 is located directly in the path of the projecting tongue 40c of the connecting rod 40 so as to retain the connecting rod in its primed position against the action of the spring 41.At this time, the lever 62b extends beneath the tongue 40c and the lever 46 is held by the control edge 14b of the lever 14 out of the path of the shoulder 40b of the connecting rod.

If the shutter release button 2 is now depressed, the lever 6b is pivoted in an anti-clockwise direction so that the switch 18 is closed and then remains closed until the button is released. At the same time, the control slider 6a is moved in the direction of the arrow 3 to pivot the lever 61, again in an anticlockwise direction, so that the end of the lever arm 61 b is moved clear of the projecting tongue 40c of the connecting rod 40. The connecting rod 40 than starts to move under the action of the spring 41 along the lever arm 62b and beneath the pivoted lever arm 61 din the opposite direction to the film transport direction whereby the cam disc 38 and the grear segments 37 begin to rotate. As the connecting rod 40 reaches the end of its stroke the arm 40d operates the shutter release peg 24c so as to release the shutter 24 and effe ct a photographic exposure.

At the end of the shutter cycle, the peg 24a closes the switch 19 so t1at now both the switches 18, 19 are closed.

During movement of the connecting rod 40 to release the shutter 24, the gear segment 37 is rotated by an amount such that its first tooth meshes with the gear wheel 32, while the peg 40a of the connecting rod 40 pivots the lever 42 anti-clockwise so that the locking edge 44a of the lever 44 can move under the action of the spring 43 into engagement with the holding edge 42c so as to hold the lever 42 in this pivoted position. The pivotal movement imparted to the lever 42 in turn drives the lever 12 clockwise so that the lever arm 1 2a disengages from the lever 9, and the lever 14 is pivoted anti-clockwise out of engagement with the lever 46, so that the latter bears against the connecting rod 40 under the action of its biasing spring 48.At the same time the brake lever 25 is lifted away from the motor pinion 16a and the peg 1 2e is moved away from the movable contact 22 whereby the switch 22, 23 is opened and the switch 21,22 is now closed. Thus, since the switches 18, 19 and 21,22 are now all closed, the motor 16 is energised so that the pinion 16a rotates and the centrifugal switch 29a closes the switch 20. It will be appreciated that the motor 16 will now remain energised through the switch 20 until the switch 20 is re-opened and hence the button 2 can now be released and the shutter 24 reprimed, whereby the switches 18, 19 are again opened.

As the motor 16 rotates the pinion 16a, the gear segment 37 is driven by way of the reduction gear 26 and the gear wheels 27,30, 31 and 32 to rotate the cam disc 38 in an anti-clockwise direction. The connecting rod 40 is thereby moved in the film transport direction against the action of the spring 41 so that the rack 40e causes the pinion 24b to re-set the shutter 24. The peg 24a is thereby moved back into the position shown in the drawing so as to re-open the switch 19, although the motor 16 remains energised by means of the switches 20 and 21,22.

Furthermore, as the pinion 16a rotates, it operates by way of the reduction gear 26 and the gear wheels 27 and 30 to 35 to rotate the take-up spool of the film cassette so as to transport the film 7. During the initial phase of the film transport, the lever 9 is lifted out of the perforation 7a by means of the control cam 1b and is then urged back against the stop 1a by the spring 11. The lever 9 is thus unable to move back into the same perforation 7a, although is urged by the spring 10 to bear against the film 7. In this position of the lever 9, the arm 9b engages the arm 12a ofthe lever 12.

The connecting rod 40 continues to move against the action of the spring 41 until, after one rotation of the cam disc 38, the rod 40 again resumes the position shown in the drawing. In this position, said one end of the connecting rod 40 pivots the lever 44 against the action of the spring 43 to disengage the edge 44a from the lever 42, while the gear segment 37 becomes disengaged from the gearwheel 32. At this stage, the film transport is not complete so that the lever 9 still bears against the imperforate region of the film 7 and the arm Sb engages the arm 12a to prevent the levers 12, 14 and 42 returning to their rest positions. Thus the switches 20 and 21,22 remain closed so that the motor 16 continues film transport.Moreover, since the control edge 14b is held clear of the lever 46, the lever 46 is urged by the spring 48 behind the shoulder 40b to prevent the connecting rod 40 being returned by the spring 41 to its rest position before film transport is complete.

When the next perforation 7a on the film 7 moves into alignment with the lever 9, the latter is urged by the spring 10 into the perforation so that the arm Sb releases the arm 12a. The lever 12 can then rotate anti-clockwise to impart clockwise rotation to the lever 42 to cause the peg 1 2e to open the switch 21, 22 and close the switch 22, 23. The motor 16 is thereby short-circuited and rapidly comes to rest to terminate film transport, the centrifugal switch 29 then opening the switch 20. Moreover, during anticlockwise rotation of the lever 12, the brake lever 25 is re-engaged with the pinion 16a and the control edge 14b of the lever 14 pivots the lever 46 away from the shoulder 40b so that all the camera components are again in the position shown in the drawing.

From the above, it will be manifest that the gear segment 37 will become operatively disengaged from the gear wheel 32 as soon as the connecting rod 40 has been returned to its starting position shown in the drawing . Thereafter, the motor 16 will continue to operate until the film 7 has been wound on by the correct amount. In each winding-on operation, the same length of film is wound onto the take-up spool of the cassette. However, due to the progressively increasing diameter of the film roll on this spool, the amount by which the gear wheel 35 rotates during each winding-on operation will vary.

By virtue of the gear segment 37 becoming disengaged from the gear wheel 32, the amount of movement of the connecting rod 40 is independent of the amount of movement of the gear wheel 35.

It will be appreciated that when the button 2 is depressed so that the lever arm 61b is held clear of the lever arm 62b, the spring 64 will urge the lever 62 in an anti-clockwise direction. Although the lever 62 is held against such movement by the tongue 40c during movement of the connecting rod 40 to release the shutter 24 and during the majority of the return movement of the connecting rod, the arrangement is such that the spring 64 is free to pivot the lever 62 as the connecting rod reaches the end of its return movement. The arm 62b is thereby moved into the path of the tongue 40c thereby providing a stop to prevent the connecting rod 40 being moved by the spring 41 back to its rest position. At this stage, with the film transport incomplete, movement of the connecting rod by the spring 41 is also prevented by the lever 46 engaging behind the shoulder 40b. However, the lever 46 is moved dlear of the shoulder 40b when film transport is complete but, if at this stage the release button 2 is still depressed, the spring 64 will retain the lever arm 62b in the path of the tongue 40c. Thus, unless the camera user sets the camera for serial exposure operation in the manner described below, if the shutter release button is accidentally maintained in its actuated condition at the end of the film transport, the lever arm 62b will retain the connecting rod 40 against movement to re-release the shutter 24 so that only a single exposure results.Of course, as soon as the button 2 is released, the lever 61 is moved in a clockwise direction by the stronger spring 63 so that the lever 62 is moved against the action of the spring 64 back into the position shown in the drawing. The lever arm 62b is thereby moved clear of the tongue 40c so that the spring 41 is free to move the connecting rod 40 but only as far as the free end of the lever Sib, where the connecting rod is then retained until further operation of the button 22 to made additional exposure.

In orderto allow the camera to be adjusted between single and serial exposure operation, a further push button 66 is mounted in said one wall of the housing 1. Movement of the further pushbutton 66 is controlled by a known form of releaseable locking mechanism indicated generally at 67 such that, when the button 66 is in a normal, depressed position indicated by the solid lines in the drawing, movement of the button in the direction of the arrow 3 releases the locking mechanism so that the button 66 is urged upwardly by a spring (not shown) into a projecting position as indicated by the broken lines in the drawing. On moving the button 66 from its projecting position in the direction of the arrow 3, the button 66 is returned to its depressed position.

The depressed position of the button 66 is arranged to adjust the camera for single exposure operation, while the projecting position of the button adjusts the camera for serial exposure operation in the manner now to be described.

Carried by the button 66 is a hook 66a which, when the button 66 is in its depressed position, is located beneath a pin 65 projecting from the lever arm 62a such that the lever 62 can be pivoted by the spring 64 into the path of movement of the tongue 40c.

However, during movement of the button 66 into its projecting position, the pin 66a is arranged to engage the pin 65 and urge the pin to pivot the lever 62b in a clockwise direction away from the path of movement of the tongue 40c. Thus, when the button 66 is in its depressed position and the shutter release button 2 is actuated, the hook 66a prevents the lever 62 being pivoted by the spring 64 in an anticlockwise direction.

It will therefore be appreciated that, in order to make a series of exposures consecutively, the button 66 is moved into its projecting position, whereafter the release button 2 is actuated and maintained in this actuated condition for the duration of the exposures. The sequence of each exposure and each subsequent film transport then occurs in the manner described above, with the switch 18 remaining closed and the lever arms 61b, 62b remaining clear of the tongue 40c for the duration of the exposures.

In the period between one complete rotation of the cam disc 38 and the termination of the film transport required to advance the film for the next exposure, the gear segment 37 is disengaged from the gear wheel 32 and the lever 46 is located in front of the shoulder 40b to prevent movement of the connecting rod 40. As will be appreciated from the foregoing comments, the connecting rod 40 is released when the lever 9 engages the next perforation 7a in the film, that is when the required film transport is complete. On releasing the button 2, the connecting rod 40 completes its current reciprocation to release and reprime the shutter 24, whereafter the spring 63 pivots the lever 61 back into its rest position shown in the drawing so that the lever arm 61b is again in the path of movement of the tongue 40c.On further actuation of the release button 2, it is then possible to effect a further series of exposures. It is only when the button 66 has been returned to its depressed position that the condition shown in the drawing is restored.

The film 7 has a title section at its trailing end and, in order to prevent this being drawn into the winding compartment of the cassette 8, a lock is provided on the cassette. When the lock is effective to prevent movement of the film 7 into the winding compartment, the lever 12 takes up its film transport position because this region of the film is arranged to have no perforations 7a in which the lever can be received.

However, the winding lock prevents the film being driven so that the motor 16 comes to rest, whereby the centrifugal switch 29a opens the switch 20 to de-energise the motor. When the cassette 8 is changed all the components return to the position shown in the drawing.

When there is no cassette 8 in the camera, the lever 9 is urged by the spring 11 against the stop la but, since it is not held by a film 7, the lever 9 is urged by the spring 10 into the cassette-receiving recess of the camera by an amount dependent on the length of the slot 9a. On actuating the shutter release button 2 for demonstration purposes, the camera operates as described above except that the position ofthe lever 9 remains unaltered, and consequently the levers 12 and 42 can return to their starting positions as soon as the lever 42 is released by the lever 44 at the end of rightward movement of the connecting rod 40.

Claims (8)

1. A still photographic camera including a shutter, a reciprocable member which is arranged to prime the shutter when moved in one direction to a first position and to release the shutter on movement in the opposite direction into a second position, means biasing the reciprocable member in the opposite direction, latch means arranged to hold the reciprocable member out of said second position against the action of the biasing means and operable to release said member upon actuation of a shutter release member, an electric motor operable to wind on a film loaded in the camera in use, means operable after a film winding-on operation to open a switch in a power supply circuit of the motor, and means operable to drivingly couple the reciprocable member with the electric motor for movement by the motor in said one direction, the reciprocable member becoming operatively disengaged from the motor when reaching said first position, wherein the latch means includes first and second release levers which are biased in opposite directions by respective springs such that in a rest position the first lever is held by its respective spring in the path of move ment of the reciprocable member in said opposite direction, while the second lever is held out of the path of said movement of the reciprocable member, the first lever being movable out of its rest position to release the reciprocable member upon actuation of the shutter release member, and the second lever being movable into the path of movement of the reciprocable member after actuation of the shutter release member and movement of the reciprocable member to its first position and then to its second position.

2. A camera as claimed in Claim 1, wherein the first and second release levers co-operate with a projection on the connecting rod and the region of the second leverwhich co-operates with said projection extends beyond the corresponding region of the first lever such that said region of the second lever can extend beneath the projection.

3. A camera as claimed in Claim 2, wherein, upon actuation of the shutter release member to move the first lever out of the path of movement of the reciprocable member, the reciprocable member is moved by said biasing means between the levers into its second position and, during subsequent movement of the reciprocable member by said motor into its first position, the second lever is pivoted by its associated spring behind the projection on the reciprocable member to prevent the reciprocable member being returned by said biasing means into its second position.

4. A camera as claimed in any one of the preceding Claims, wherein the first lever, after actuation and subsequent release of the shutter release member, is urged by its associated spring back into its rest position to return into the path of the reciprocable member and to urge the second lever out of the path of said reciprocable member.

5. A camera as claimed in any preceding Claim and including a manually operable control member, and means operable, when the control member is in an operative position and the shutter release member is actuated, to retain the second lever out of the path of movement of the reciprocable member to allow a series of exposures to be made consecutively.

6. A camera as claimed in Claim 5, wherein the control member is a pushbutton arranged so as to be movable, by sequential depression thereof, between said operative position, and an inoperative position in which the second lever is movable into the path of the reciprocable member.

7. A camera as claimed in Claim 5 or Claim 6, wherein said means includes an abutment movable with the control member and operable to pivot the second lever against the action of its associated spring during movement of the control member into its operative position.

8. A still photographic camera as claimed in Claim 1, comprising the combination and arrangement of parts substantially as hereinbefore described with reference to, and as shown in, the accompanying drawing.