JP3549036B2 - Film counter mechanism and reset method thereof - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a film counter mechanism for counting the transfer of one frame of a photographic film. And how to reset it It is about.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a film unit with a lens in which a 135-size photographic film is stored in a unit body in which a photographic mechanism such as a photographic lens, a film winding mechanism and a shutter mechanism is incorporated, for example, "Sharp Run Hi" (product name), etc. Is manufactured and sold by the present applicant. Film units with lenses are inexpensive so that you can easily purchase and enjoy photography.
[0003]
Such a film unit with a lens incorporates a film counter mechanism for displaying the remaining number of stored photographic films. This film counter mechanism is provided with a disk-shaped number-of-photographs display plate having a number-of-photographs scale provided on its surface and having teeth formed on the outer periphery thereof, and meshing with a perforation of the photographic film, and each time the photographic film is wound up by one frame. A driven sprocket that rotates one turn, and a one-tooth gear that is a drive gear that has one tooth that rotates coaxially and integrally with the driven sprocket, meshes with the teeth of the number-of-photographs display plate, and rotates by one division. It is composed of
[0004]
The one-tooth gear is configured such that a part of the outer periphery of a shaft having a substantially elliptical cross section is cut out and the cutout portion is formed as a tooth, and each part of the outer periphery faces the teeth of the number-of-photographs display plate during rotation. That is, when the arc portion faces the teeth of the number-of-photographs display plate, it slightly enters between the teeth, thereby preventing the number-of-photographs display plate from accidentally rotating due to vibration or impact. However, since the one-tooth gear is not a perfect circle, the amount of engagement with the number-of-photographs display plate changes during one rotation, and rattling occurs between the one-tooth gear and the number-of-photographs display plate, and during one rotation. In some cases, the number-of-photographs display plate is rotated by two divisions.
[0005]
In order to solve the above-mentioned problem, as shown in FIG. 15, a locking gear 106 which is coaxially and integrally rotated is provided below the number-of-photographs display plate 105, and is coaxially provided below the one-tooth gear 107. There has been proposed a film counter mechanism provided with a locking cam 108 which is integrally rotated and meshed with a locking gear 106. According to this film counter mechanism, the locking cam 108 engages with the locking gear 106 until just before the one-tooth gear 107 rotates the number-of-photographs display plate 105, and the careless rotation of the number-of-photographs display plate 105 occurs. When the one-tooth gear 107 rotates the number-of-photographs display plate 105, the one-tooth gear 107 immediately meshes with the locking gear 106 to prevent unnecessary rotation of the number-of-photographs display plate 105.
[0006]
[Problems to be solved by the invention]
However, in the above-mentioned film counter mechanism, since the amount of engagement between the one-tooth gear 107 and the number-of-photographs display plate 105 is small, the one-tooth gear 107 does not mesh with the number-of-photographs display plate 105 and idles. Is displayed less than the actual number of shots. In order to solve this, it is conceivable to increase the amount of engagement with the number-of-photographs display plate 105 by enlarging the teeth 107a of the one-tooth gear 107. There is a problem that the removal of the gear 107 becomes worse and the number-of-photographs display plate 105 is rotated extra.
[0007]
Also, when the number of images that can be photographed by a film unit with a lens or the like using the above film counter mechanism is increased, the pitch of the teeth of the locking gear 106 is reduced, and the amount of engagement between the locking gear 106 and the locking cam 108 is reduced. However, there is a problem that the effect of preventing careless rotation is reduced. In order to solve this, the outer diameter of the locking gear 106 can be increased to increase the amount of engagement with the locking cam 108. However, for example, if the outer diameter of the locking gear 106 is made larger than that of the number-of-images display plate 105 on the upper part, the number-of-images display plate 105 is changed after the locking cam 108 and the cam shaft integrally formed with the one-tooth gear 107 are assembled. When assembling, there is a problem that the locking gear 106 cannot be moved to a lower portion of the one-tooth gear 107, so that the assembling cannot be performed.
[0008]
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to prevent unnecessary rotation or inability of the display of the number-of-images display plate due to rattling of the drive gear or idling.
[0009]
[Means for Solving the Problems]
In order to solve the above problem, the film counter mechanism according to claim 1 has a scale of the number of images to be taken on the surface. Supported rotatably The number-of-photographs display plate is coaxially and integrally rotated with the number-of-photographs display plate. , Multiple teeth formed on the outer circumference A locking gear, A stepping gear formed on the outer periphery of the number-of-photographs display plate and having a plurality of teeth whose phases are shifted by less than half a pitch with respect to the locking gear in the rotation direction of the number-of-photographs display plate; A driven sprocket that is rotated by the transfer of one frame of the photographic film, and is rotated coaxially and integrally with the driven sprocket. Step gear Mesh with his teeth Display the number of shots A drive gear that rotates by one division and a drive gear that is coaxially and integrally rotated with the drive gear Step gear And a locking cam for preventing the rotation of the number-of-photographs display plate by partially entering one of the teeth of the locking gear while not meshing with the locking gear.
[0010]
In the film counter mechanism according to the second aspect, the shape of the drive gear is changed only when the number-of-photographs display plate is rotated. Step gear This is a shape that comes into contact with.
[0011]
In the film counter mechanism according to the third aspect, a scale of the number of images to be taken is marked on the surface. Rotatably supported Number of shots display board, A locking gear formed on the outer periphery of the number-of-photographs display plate and having a plurality of teeth; Is provided at the bottom of the It has a plurality of teeth whose phases are shifted by less than half a pitch with respect to the locking gear in the rotation direction of the number-of-photographs display plate. A stepping gear, a driven sprocket which is rotated by transferring one frame of the photographic film, and is rotated coaxially and integrally with the driven sprocket and meshes with the teeth of the stepping gear to rotate the number-of-photographs display plate by one division. A drive gear to be provided, and provided above the drive gear, coaxially and integrally rotated, and while the drive gear is not meshed with the stepping gear, Locking gear And a locking cam for preventing a rotation of the number-of-photographs display plate by partially entering one of the teeth.
[0012]
Further, in the film counter mechanism according to the fourth aspect, the shape of the drive gear is such that it is in contact with the stepping gear only when the number-of-photographs display plate is rotated.
[0013]
A film counter mechanism according to claim 5. The reset method of the above-mentioned is that the number-of-photographs display plate on the surface of which the number-of-photographs scale is marked along the rotation direction, a stepping gear formed integrally with the number-of-photographs display plate, and a phase with respect to the stepping gear. The gear is formed with teeth whose teeth are shifted, a driven sprocket rotated by one frame of the photographic film, and coaxially rotated with the driven sprocket to mesh with the teeth of the stepping gear. A drive gear that rotates the number-of-photographs display plate by one division, and a part that is coaxially rotated with the drive gear and one between the teeth of the locking gear while the drive gear is not engaged with the stepping gear. A locking cam that is inserted to prevent the rotation of the number-of-photographs display plate, and a tooth that is provided on one or both of the outer circumference of the locking gear and the outer circumference of the stepping gear and is used at the end of counting; Between the teeth used at the start of counting After the counting of the film counter mechanism having the toothless section having no teeth for the set number of teeth is completed, the number-of-photographs display plate is forcibly rotated from the outside using the toothless section, and at the start of counting. Face the teeth to be used to either or both the locking cam and the drive gear It is like that.
[0014]
According to the above solution, when the photographic film is wound up by one frame, the driven sprocket rotates and the driving gear rotates together. The drive gear is Step gear Mesh with Display the number of shots Rotate by one division, The teeth of the stepping gear are smaller than the teeth of the locking gear by less than half a pitch in the rotation direction of the number-of-images display plate. Since they are provided out of phase, the drive gear and Step gear The amount of engagement with , The number of shots display board certainly It is rotated by one division. Also, after the rotation of the number-of-photographs display plate is completed, Step gear And the drive gear are easily disengaged from each other, so that the number-of-images display plate is not rotated extra. Further, the drive gear is used except when rotating the number-of-photographs display plate. Step gear Is not interfered with, the display panel for the number of images to be taken is not rotated excessively by a portion other than the teeth of the drive gear.
[0015]
To increase the number of images that can be taken, a stepping gear is provided below the number-of-images display plate to rotate the number-of-images display plate by one graduation, and the teeth of the number-of-images display plate are used for locking. . Thereby, even if the pitch of the teeth of the number-of-photographs display plate becomes narrow, the number-of-photographs display plate can be increased in diameter and the amount of engagement with the locking cam can be increased.
[0016]
Furthermore, since the number-of-images display plate can be forcibly rotated from the outside by using the missing tooth section, the film counter mechanism can be easily reused.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 2 shows the appearance of a film unit with a lens using the present invention. The lens-fitted film unit 2 is of a type designed to be thinner, and includes a unit body 3 having a built-in photographing mechanism and the like and an outer case 4 for housing the unit body. The outer case 4 has such a contour as to expose the hoisting knob 5 incorporated in the unit main body 3, and has a strobe light emitting unit 6, a shutter button 7, a photographing lens 8, an object side finder window 9 a, and a photographing number display window 10. There is a hole for exposing the like. Further, a strobe charging switch 11 is provided below the strobe light emitting unit 6.
[0018]
As shown in an exploded view in FIG. 3, the unit main body 3 includes a main body base 12, an exposure unit 13, a strobe unit 14, a rear cover 15, and a front cover 16, and these are assembled by nail engagement.
[0019]
The main body 12 is made of opaque plastic, and a light-shielding tube 19 is provided on the optical axis 18. On the back side, there is formed an aperture for determining the exposure range to the photographic film. On both sides of the light-shielding tube 19, a patrone storage chamber 20 for storing a patrone and a film roll chamber 21 for storing a photographic film in a roll shape are formed. The front surface of the outer wall of the patrone storage room 20 has a shape protruding forward from the front surface of the outer wall of the film roll room 21.
[0020]
The strobe unit 14 includes a printed circuit board 24 and the light emitting unit 6. On the printed circuit board 24, an electric component 24a constituting a strobe circuit and a light emitting switch 24b turned on by a shutter mechanism of the exposure unit 13 are attached. Further, the light emitting section 6 has a discharge tube, a reflector, and a diffusion plate 6a held by a resin holder 6b.
[0021]
The rear cover 15 is formed of an opaque plastic, and has a film supporting surface 15a at a portion facing the aperture. Pull-top lids 15b and 15c that cover the bottom surfaces of the patrone storage chamber 20 and the film roll chamber 21 are provided on the bottom side. The cover 15b serves as a take-out cover for taking out the cartridge containing the exposed photographic film. An eyepiece side finder window 9b is formed above the film support surface 15a.
[0022]
The front cover 16 is made of opaque plastic, and has a shutter button 7, an object-side finder window 9a, a number-of-shots display window 10, a strobe charging switch 11, and the like. The front cover 16 is formed with a protrusion 26 corresponding to the protrusion of the patrone storage chamber 20, and the protrusion 26 serves as a grip during photographing.
[0023]
The exposure unit 13 has a film winding mechanism, a film counter mechanism, a shutter mechanism, and the like incorporated in a base portion 28 formed of opaque plastic. The photographing lens 8 is incorporated on the front side of the base 28, and a finder 29 is incorporated on the upper part of the base 28. A holding plate 30 made of transparent plastic is attached to an upper portion of the finder 29. The exposure unit 13 is detachably attached to the front surface of the main body base 12.
[0024]
As shown in FIG. 4, the film counter mechanism meshes with the perforations 32a of the photographic film 32, and the driven sprocket 33 rotates once when the photographic film 32 is wound up by one frame in the direction of the arrow, and the driven sprocket 33 The camshaft 34 is assembled with the camshaft 34 and integrally rotated, and the number-of-photographs display panel 35 is rotated by one division by one rotation of the camshaft 34.
[0025]
As shown in FIG. 5, the camshaft 34 and the number-of-images display plate 35 are rotatably inserted into a bearing 37 and a shaft 38 formed on the upper surface of the mechanical base 28 of the exposure unit 13. The driven sprocket 33 and the driven sprocket 33 are assembled in the mechanical base 28 when the cam shaft 34 is inserted into the bearing part 37.
[0026]
On the camshaft 34, a one-tooth gear 40, a locking cam 41, a stop cam 42, a shutter charge cam 43, and a shaft 44, which are driving gears for driving the number-of-photographs display plate 35, are integrally formed from the upper side. A groove is formed on the outer circumference of the winding cam 42. When the photographic film 32 is wound up by one frame, a well-known locking lever is engaged to regulate the winding of the photographic film. The shutter charge cam 43 is for moving a well-known shutter drive lever to a shutter charge position in conjunction with the winding of the photographic film 32 for one frame.
[0027]
As shown in FIG. 1, the one-tooth gear 40 has one projection 40a protruding substantially radially from the peripheral surface of a column coaxial with the shaft 44, and the projection 40a makes one rotation of the one-tooth gear 40. Each time, it is engaged once with the teeth 35a formed on the outer periphery of the number-of-photographs display plate 35, and the number-of-photographs display plate 35 is rotated by one division. The one-tooth gear 40 is shaped so as not to contact the number-of-photographs display plate 35 except when the number-of-photographs display plate 35 is actually rotated. There is no need to rotate the shadow number display plate 35 excessively in other parts.
[0028]
The locking cam 41 meshes with teeth 46a of a locking gear 46 formed integrally with the lower portion of the number-of-photographs display plate 35, thereby preventing the number-of-photographs display plate 35 from inadvertently rotating. The locking cam 41 is composed of a cylinder coaxial with the shaft 44, and a notch 41a is provided on the peripheral surface of the cylinder so as to sandwich the projection 40a of the one-tooth gear 40. The notch 41a faces the locking gear 46 when the one-tooth gear 40 meshes with the number-of-photographs display plate 35 and rotates by one division, and releases the meshing with the locking gear 46. Since the arc diameter of the teeth 46a of the locking gear 46 and the outer diameter of the locking cam 41 are the same, there is no hindrance to the rotation of the locking cam 41.
[0029]
Further, the teeth 46a of the locking gear 46 are provided with a slightly shifted phase from the teeth 35a of the number-of-photographs display plate 35. As a result, the amount of meshing when the projection 40a of the one-tooth gear 40 first contacts the tooth 35a of the number-of-images display plate 35 differs from that of the conventional tooth 35b, which is indicated by a two-dot chain line and has the same phase as the tooth 46a. This is much larger than the meshing amount, so that the one-tooth gear 40 does not mesh with the number-of-photographs display plate 35, and does not run idle.
[0030]
Further, when the one-tooth gear 40 completes the rotation of the number-of-photographs display plate 35 and releases the engagement with the number-of-photographs display plate 35, as shown in FIG. 6, the protrusion 40a and the teeth 35a may not be caught. In addition, since the projection 40a comes off straight, the projection 40a does not come off the teeth 35a and the number-of-images display plate 35 is not rotated excessively.
[0031]
As shown in FIG. 5, a holding plate 30 is mounted on the upper part of the exposure unit 13. The holding plate 30 has a shaft hole 30 a into which the shaft 38 of the mechanical base 28 is inserted, and a protrusion at the upper end of the cam shaft 34. And a shaft hole 30b into which the formed shaft 44 is inserted. A pin 30c is formed on the lower surface of the holding plate 30 to be inserted into a shaft 48 for a locking lever formed on the mechanical base 28, so that the distance between the shafts 38, 44, 48 is kept constant. It has become. Accordingly, the engagement between the one-tooth gear 40 and the number-of-photographs display plate 35 and the engagement between the locking cam 41 and the locking gear 46 become more reliable, and more accurate display of the number of captured images can be performed.
[0032]
On the upper surface of the holding plate 30, a lens 30d is formed at a position arranged above the number-of-photographs display plate 35. The lens 30d faces the number-of-photographs display window 10 of the front cover 16 when the unit main body 3 is assembled, and enlarges the display of the number-of-photographs scale of the number-of-photographs display plate 35.
[0033]
Next, the operation of the present embodiment will be described. The film unit with lens 2 shown in FIG. 2 performs photographing by pressing the shutter button 7 after determining the composition by looking through the eyepiece side finder window 9b. After the photographing, the winding knob 5 is rotated counterclockwise in FIG. 2 to wind up the exposed photographic film 32 onto the patrone and to charge the shutter for the next photographing.
[0034]
When the winding knob 5 is operated to rotate, the spool of the cartridge engaged with the winding knob 5 is rotated, and the photographic film 32 whose end is locked to the spool is, as shown in FIG. One frame of the shooting screen is transferred toward. When the photographic film 32 is transported by one frame, the driven sprocket 33 meshed with the perforation 32a of the photographic film 32 makes one rotation, and the camshaft 34 coaxially mounted on the driven sprocket 33 moves counterclockwise in FIG. Is rotated once.
[0035]
When the camshaft 34 is rotated counterclockwise, the projection 40a of the one-tooth gear 40 formed integrally with the camshaft 34 meshes with the teeth 35a of the number-of-photographs display plate 35 as shown in FIG. Since the one-tooth gear 40 does not come into contact with the number-of-images display plate 35 until the projection 40a meshes with the tooth 35a, the number-of-images display plate 35 does not rotate unnecessarily. The meshing between the projection 40a and the tooth 35a is based on the conventional tooth provided on the tooth 46a of the locking gear 46 in the same phase because the tooth 35a is out of phase with the tooth 46a of the locking gear 46. Since it is much larger than the engagement with the lens 35b, the number-of-images display plate 35 can be surely rotated by one division.
[0036]
Further, since the shafts 37, 38, and 48 of the mechanical base 28 are maintained at a constant distance between the shafts by the holding plate 30, the one-tooth gear 40 cannot mesh with the number-of-photographs display plate 35 due to the widening between the respective shafts. Never idle.
[0037]
The locking cam 41 always meshes with the teeth 46a of the locking gear 46 so that the number-of-photographs display plate 35 does not inadvertently rotate even if a strong shock or vibration is applied to the lens-fitted film unit 2. Inadvertent rotation is prevented. When the projection 40a of the one-tooth gear 40 meshes with the tooth 35a of the number-of-photographs display plate 35 and rotates, the notch 41a formed on the outer periphery faces the locking gear 46, and Since the engagement with the locking gear 46 is released, the number-of-photographs display plate 35 can rotate without any trouble.
[0038]
As soon as the one-gear gear 40 completes the rotation for one graduation of the number-of-photographs display plate 35, the locking cam 41 meshes with the locking gear 46, thereby preventing unnecessary rotation of the number-of-photographs display plate 35. Further, since the teeth 35a of the number-of-images display plate 35 are provided out of phase with respect to the teeth 46a of the locking gear 46, the projections 40a of the one-tooth gear 40 , The number-of-photographs display plate 35 does not rotate excessively.
[0039]
Next, another embodiment of the present invention will be described. FIGS. 7 and 8 schematically show a film counter mechanism of a film unit with a lens loaded with a photographic film having a novel arrangement of perforations. A bearing 51 and a shaft 52 are integrally formed on the upper surface of the mechanical base 50 of the exposure unit. A cam shaft 53 and a number-of-photographs display plate 54 are rotatable on the bearings 51 and 52. Has been inserted. A driven sprocket 55 is coaxially mounted inside the mechanical base 50 at the lower end of the cam shaft 53.
[0040]
The driven sprocket 55 is provided with two pairs of large teeth 57 and small teeth 58 that are rotationally symmetrical on the outer peripheral surface 55a, and are moved in the opposite direction in FIG. It is rotated half a clockwise (180 °).
[0041]
The photographic film 59 in which the driven sprocket 55 is meshed has one large perforation 60 in which the large teeth 57 are meshed and one small perforation 61 in which the small teeth 58 are meshed per frame of the photographing screen. The large perforations 60 and the small perforations 61 are alternately arranged in the longitudinal direction of the film, and two types of intervals, a long interval and a short interval, are alternately used. One frame of the shooting screen is arranged between the large perforations 60 and the small perforations 61 arranged at long intervals, and the large perforations 60 and the small perforations 61 arranged at short intervals define the interval between each frame. It is what you do.
[0042]
The patrone 63 in which the photographic film 59 is stored has an outer case 63a, a spool shaft 63b, and the like formed of plastic, and has a film entrance 64 through which the photographic film 59 enters and exits. A plastic lid member 65 for opening and closing the film entrance 64 is incorporated. When the patrone 63 is not used, the photographic film 59 is completely housed inside to the front end, and when loaded into a camera or the like, the lid member 65 is first rotated to open the film entrance 64, and thereafter the spool shaft 63b Is rotated clockwise in the figure, so that the photographic film 59 is sent out from the film entrance 64.
[0043]
When the patrone 63 is loaded into the film unit with a lens, the patrone 63 is loaded in a state where all the photographic films 59 have been pulled out from the patrone 63 in advance, similarly to the case of the patrone storing the conventional 135-size photographic film. Then, the winding knob 67 engaged with the spool shaft 63b is rotated every time one frame is photographed on the photographic film 59, so that the entire exposed photographic film 59 is finally wound into the cartridge 63.
[0044]
The driven sprocket 55 is stopped in a state where the large teeth 57 are engaged with the large perforations 60 at first, so that the photographic film 59 is positioned. When the photographic film 59 is transferred, the large teeth 57 are urged by the large perforations 60, the driven sprocket 55 is slightly rotated, and the large teeth 57 come off from the large perforations 60, and the outer peripheral surface 55a is removed. It is slid on 59. However, with this amount of rotation, the small teeth 58 cannot move to a position where they mesh with the next small perforation 61. Therefore, the cam shaft 53 assists the rotation of the driven sprocket 55, and moves the small teeth 58 to a position where the small teeth 58 can mesh with the next small perforations 61.
[0045]
The camshaft 53 is formed by integrally forming a two-tooth gear 69 as a driving gear, a locking cam 70, a locking cam 71, a shutter charge cam 72, a biasing cam 73, and a shaft 74 from above. The shaft 74 is rotatably inserted into the bearing portion 51, and the driven sprocket 55 is assembled at the lower end.
[0046]
The winding cam 71 has two grooves 71a formed on the outer periphery thereof. When the photo film 59 is wound up by one frame, a well-known locking lever is engaged to regulate the winding of the photo film 59. Things. The shutter charge cam 72 has a pair of blade-shaped protruding portions 72a arranged rotationally symmetrically, and is used to move a well-known shutter drive lever to a shutter charge position in conjunction with winding up of the photographic film 59 by one frame. Things.
[0047]
As described above, the urging cam 73 is a member that assists rotation of the driven sprocket 55 to engage the small teeth 58 with the small perforations 61 during film transfer. A pair of protrusions 73a are formed on the outer periphery of the biasing cam 73 and are rotationally symmetrically arranged. When the protrusions 73a are pressed by a biasing member (not shown), the cam member 53 is moved by a film. It is rotated in the driven direction.
[0048]
As shown in FIG. 9, the two-tooth gear 69 includes a pair of protrusions 69 a that are protruded in a substantially radially rotationally symmetrical manner from the circumferential surface of a cylinder coaxial with the shaft 74. Each time it rotates by half, it meshes with a tooth 54a formed on the outer periphery of the number-of-photographs display plate 54, and rotates the number-of-photographs display plate 54 by one division. Further, the two-tooth gear 69 is shaped so as not to be in contact with the number-of-photographs display plate 54 except when the number-of-photographs display plate 54 is actually rotated. I won't let you.
[0049]
The locking cam 70 meshes with teeth 76a of a locking gear 76 formed integrally with the lower portion of the number-of-photographs display plate 54 to prevent the number-of-photographs display plate 54 from being accidentally rotated. The locking cam 70 is composed of a cylinder coaxial with the shaft 74, and a pair of notches 70a are provided on the peripheral surface of the cylinder so as to sandwich the projection 69a of the two-tooth gear 69. These notches 70a face the locking gear 76 when the two-tooth gear 69 meshes with the number-of-photographs display plate 54 and rotates by one division, and releases the meshing with the locking gear 76. Since the arc diameter of the teeth 76a of the locking gear 76 and the outer diameter of the locking cam 70 are the same, there is no hindrance to the rotation of the locking cam 70.
[0050]
The reason why the two teeth 69a of the two-tooth gear 69 and the two notches 70a of the locking cam 70 are provided rotationally symmetrically is to drive each mechanism each time the cam shaft 53 rotates half a turn. Yes, for example, a camshaft that drives each mechanism every １ ／ rotation has three projections and notches.
[0051]
The phase of the teeth 76a of the locking gear 76 is slightly shifted from the phase of the teeth 54a of the display panel 54. As a result, the amount of engagement when the projection 69a of the two-tooth gear 69 first contacts the tooth 54a of the number-of-images display plate 54 differs from that of the conventional tooth 54b, which is indicated by a two-dot chain line and has the same phase as the tooth 76a. This is much larger than the meshing amount, so that the two-tooth gear 69 does not mesh with the number-of-photographs display plate 54 and runs idle.
[0052]
When the two-tooth gear 69 completes the rotation of the number-of-images display plate 54 and releases the engagement with the number-of-images display plate 54, the protrusion 69a and the teeth 54a may not be caught as shown in FIG. In addition, since the projection 69a comes off straight, the projection 69a does not come off from the tooth 54a and the number-of-images display plate 54 is not rotated excessively.
[0053]
A shaft 78 is formed on the upper part of the two-tooth gear 69, and the shaft 78 is inserted into a hole 80 formed on a holding plate 79 assembled on the upper part of the mechanical base 50. The holding plate 79 is also provided with a hole 81 into which the shaft 52 is inserted. By keeping the distance between the number-of-photographs display plate 54 and the cam shaft 53 constant, the two-tooth gear 69 and the number-of-photographs display plate Engagement with 54 is further ensured.
[0054]
The film counter mechanism described in each of the above-described embodiments is for counting the number of photographic films having a length of, for example, about 27, which can be photographed. When the number of images to be taken is increased, the pitch of the teeth of the locking gear is narrowed, the amount of engagement with the locking cam is reduced, and the effect may be reduced. A film counter mechanism according to still another embodiment described below solves this problem.
[0055]
The film counter mechanism shown in FIG. 11 is for counting the number of photographed 135-size photographic films, for example, capable of photographing 39 sheets, and is a bearing unit integrally formed on the upper surface of the mechanical base 85 of the exposure unit. A cam shaft 88 and a number-of-images display panel 90 integrally formed with a step gear 89 are rotatably inserted into the shaft 86 and the shaft 87. In the inside of the mechanical base 85, a driven sprocket meshed with the perforation of the photographic film is coaxially attached to the lower end of the cam shaft 88.
[0056]
A well-known shutter charge cam 92 and a stop cam 93 are formed on the cam shaft 88, and a drive gear for meshing with a stepping gear 89 and rotating the number-of-images display plate 89 by one division is provided above the cam shaft 88. And a locking cam 96 that meshes with the number-of-photographs display plate 90 to prevent inadvertent rotation while the one-tooth gear 95 does not mesh with the step-up gear 89. ing.
[0057]
As shown in FIG. 12, the one-tooth gear 95 is provided with a projection 95a that protrudes substantially radially from the peripheral surface of a cylinder provided coaxially with the cam shaft 88. As shown in FIG. 13, each time the cam shaft 88 is rotated once by the transfer of the photographic film, the projection 95a meshes with the teeth 89a of the stepping gear 89 to rotate the number-of-photographs display plate 90 by one division. . Since the one-tooth gear 95 is formed so as not to be in contact with the stepping gear 89 except when the number-of-photographs display plate 90 is actually rotated, it is necessary to rotate the number-of-shadow display plate 90 excessively due to rattling or the like. There is no.
[0058]
The locking cam 96 is formed of a cylinder coaxial with the cam shaft 88, and engages with the teeth 90a of the number-of-photographs display plate 90 as shown in FIG. Prevent movement. A notch 96 a is provided on the peripheral surface of the locking cam 96 so as to sandwich the projection 95 a of the one-tooth gear 95. As shown in FIG. 13, the notch 96a faces the number-of-photographs display plate 90 when the one-tooth gear 95 meshes with the step-up gear 89, and releases the engagement with the number-of-photographs display plate 90. It is.
[0059]
On the outer periphery of the number-of-photographs display plate 90, a number of teeth 90a necessary for counting the number of photo films to be loaded are formed, and the pitch of each tooth 90a is to count 39 photo films. It is narrower than that of the number-of-photographs display plate that counts 27 photo films. Therefore, the number-of-images display plate 90 of the present embodiment has a large diameter to the extent that it does not interfere with the rear cover and has a large amount of engagement with the locking cam 96, so that even if the pitch of the teeth 90a is small, it is ensured. In addition, unnecessary rotation of the number-of-images display plate 90 can be prevented.
[0060]
The stepping gear 89 below the number-of-photographs display plate 90 has a smaller diameter than the number-of-photographs display plate 90. The number of teeth 89a formed on the outer periphery is the same as the number of teeth 90a of the number-of-photographs display plate 90 and is provided with a slight phase shift. As a result, as shown in FIG. 13, the amount of engagement between the protrusion 95 a of the one-tooth gear 95 and the teeth 89 a of the step gear 89 becomes significantly large, so that the one-tooth gear 95 can mesh with the step gear 89. There is no such thing as spinning without it.
[0061]
When the one-tooth gear 95 has finished rotating the stepping gear 89, as shown in FIG. 14, the projection 95a can be easily removed from the tooth 89a, so that the projection 95a is caught by the tooth 89a. The number display plate 90 is not rotated extra.
[0062]
The reason why the number-of-photographs display plate 90 is used for locking is that if the locking gear is disposed below the number-of-photographs display plate and has a larger diameter than that of the number-of-photographs display plate, the camshaft will be moved to the mechanical base as in the conventional case. This is because it becomes impossible to assemble the number-of-photographs display plate after assembling, but if the number-of-photographs display plate is used for locking as in the present embodiment, the conventional assembling method should be used even if the diameter is increased. Can be.
[0063]
A shaft 98 is formed on the upper part of the one-tooth gear 95, and the shaft 98 is inserted into a hole 100 formed on a holding plate 99 mounted on the upper part of the mechanical base 85. The holding plate 99 is also provided with a hole 101 into which the shaft 87 is inserted. The one-tooth gear 95 and the step-up gear 89 maintain the distance between the number-of-photographs display plate 90 and the cam shaft 88 constant. , And the engagement between the locking cam 96 and the number-of-photographs display plate 90 is further ensured.
[0064]
Also, in each of the above film counter mechanisms, the count operation can be more reliably performed by enlarging a part of the teeth of the locking gear and the number-of-photographs display plate. Hereinafter, the film counter mechanism in which the count number is increased as shown in FIGS.
[0065]
The number-of-photographs display plate 110 shown in FIG. 16 is used in place of the number-of-photographs display plate 90 in the film counter mechanism shown in FIG. Scale numbers from "0" to "39" and scale points appropriately arranged between them are marked on the same circumference. The teeth 111 formed on the outer periphery of the number-of-photographs display plate 110 are locking teeth for preventing inadvertent rotation of the number-of-photographs display plate 110, and are provided integrally below one step of the number-of-photographs display plate 110. The provided gear 112 is a stepping gear that rotates the number-of-photographs display plate 110 by one division.
[0066]
Of the teeth 111 of the number-of-photographs display plate 110, the teeth denoted by reference numerals 111a, 111b, 111c, 111d, 111e, 111f, and 111g are slightly larger than the other numerous teeth. When the camshaft 88 meshes with the locking cam 96, the meshing state between the number-of-photographs display plate 110 and the camshaft 88 becomes tight, so that rattling of the number-of-photographs display plate 110 can be suppressed.
[0067]
The gap 114 formed by the teeth 111b and 111c is used for positioning the portion that is first engaged with the locking cam 96 of the cam shaft 88, that is, the position of the number-of-photographs display plate 110, when assembling the exposure unit including the film counter mechanism. It is the part that is done.
[0068]
In the assembly of the exposure unit, the gap between the number-of-photographs display plate 110 and the camshaft 88 is not restricted until the protection plate 99 is assembled to the mechanical base 85. Becomes very unstable. This is a more serious problem for a film counter mechanism with an increased number of images, in which the amount of engagement between the number-of-images display plate and the camshaft is small. Therefore, if vibration or impact is applied to the mechanical base 85 for a short time before the protection plate 99 is assembled, the number-of-photographs display plate 110 may be inadvertently rotated and the initial position may be shifted. A film unit with a lens incorporating an exposure unit in which the initial position of the number-of-photographs display plate 110 is shifted has a problem that an accurate counting operation cannot be performed.
[0069]
However, by slightly increasing the size of the teeth 111b and 111c constituting the gap 114, the engagement between the number-of-photographs display plate 110 and the locking cam 96 until the protection plate 99 is assembled can be firmly performed. Therefore, it is possible to obtain an operational effect that the number-of-photographs display plate 110 does not deviate from the mounting position due to a slight impact or vibration.
[0070]
The unit body completed by loading the photo film patrone is subjected to a function test by shutter release.In order to minimize the amount of photo film used for this function test, the exposure unit must be in the state immediately before the shutter charge. It is to be mounted on the base and loaded with a photo film patrone. The reason why the teeth 111f and 111g are enlarged is that the exposure unit is in the state immediately before charging when the tooth gap 116 formed by the teeth 111f and 111g is engaged with the locking cam 96 of the cam shaft 88. This is for preventing the exposure unit from being shutter-charged due to the backlash of the number-of-photographs display plate 110 at this time.
[0071]
When the photographing of all the frames of the photo film is completed, the rib 118 formed on the lower surface of the number-of-photographs display plate 110 engages with the rib of the locking lever for stopping the film, and the film is stopped. To prevent all of the photographic film from being wound up into the patrol. The reason why the teeth 111a, 111b, 111c, 111d, 111e, and 111f are enlarged is to precisely define the last film winding period.
[0072]
As shown in FIG. 17, when the gap 120 formed by the teeth 111 a and 111 b is engaged with the locking cam 96 of the cam shaft 88, the rib 118 of the number-of-photographs display plate 110 and the rib 122 of the locking lever 121 are provided. Is only 0.3 mm. This is because the positions where the ribs 118 and the ribs 122 are arranged are at positions where the number-of-photographs display plate 110 moves at a pitch of approximately 0.6 mm each time the plate rotates by one division. When the tooth gap 114 of the plate 110 meshes with the locking cam 96, the amount of engagement between the rib 118 and the rib 122 is 0.3 mm.
[0073]
In this way, if the gap between the ribs 118 and 120 is small or the engagement amount is small and the number-of-photographs display plate 110 is rotated carelessly, the shutter is charged again and the photo film is re-charged. However, when the teeth 111a, 111b, and 111c are enlarged to eliminate the backlash of the number-of-photographs display plate 110, such a problem can be prevented. it can.
[0074]
Also, when the tooth gap 124 formed by the teeth 111d and 111e is engaged with the locking cam 96, the rib 118 of the number-of-images display plate 110 and the rib 122 of the locking lever 121 are moved as shown in FIG. Immediately before the disengagement, the engagement amount is 0.3 mm. However, since the teeth 111d and 111e constituting the interdental teeth 124 are also enlarged and the rattling of the number-of-photographs display plate 110 is suppressed, the engagement of the ribs 118 and 122 does not come off.
[0075]
Similarly, when the gap 126 formed by the teeth 111e and 111f is engaged with the locking cam 96, as shown in FIG. The mesh is disengaged and the gap L is only 0.3 mm. However, since the ratchet of the number-of-photographs display plate 110 is suppressed by making the teeth 111e and 111f large, the number-of-photographs display plate 110 rotates carelessly and the engagement of the ribs 118 and 122 is unnecessarily long. Nothing happens.
[0076]
As shown in FIG. 16, the outer diameter of the teeth 124, 126, and 116 formed by the teeth 111 d to 111 g is increased in the number-of-photographs display panel 110 so that the teeth 112 a of the step gear 112 are hidden. I have.
[0077]
When the number-of-photographs display plate 110 is supplied toward the automatic assembling process to the mechanical base 85, a plurality of the number-of-images display plates 110 are moved in the same position in a guide or the like, and FIG. As described above, the number-of-photographs display boards 110 are in a state of abutting before and after in the transport direction. When the number-of-photographs display plate 110 reaches the take-out position, the number-of-photographs display plate 110 is vertically lifted upward and assembled to the shaft 87 of the mechanical base 85.
[0078]
When the photograph number display plate 110 is lifted, if the teeth 111 of the front and rear photograph number display plates 110 and the teeth 112a of the stepping gear 112 overlap, the photograph number display plate 110 on the rear side in the transport direction is caught. As a result, the robot may drop from the guide or change its posture. However, if the teeth 112a of the stepping gear 112 are hidden by increasing the outer diameters of the teeth 124, 126, 116, it is possible to prevent the number-of-photographs display plates 110 from overlapping each other as shown in FIG.
[0079]
In addition, the above-mentioned number-of-photographs display plate in which the specific teeth are enlarged and the number-of-photographs display plate in which the outer diameter between the specific teeth is increased are used for a general 27-sheet film other than the film counter mechanism whose count number is increased. And the same effect can be obtained.
[0080]
The film unit with the lens is collected and disassembled after use by the user, and each part is reused or reused. The exposure unit provided with the film counter mechanism is reused after the number-of-photographs display plate is reset and after a function test of the shutter mechanism and the like. However, removing the number-of-images display plate from the exposure unit once and reassembling it at the reset position has a problem in that work efficiency is poor. The following describes the number-of-photographs display panel that facilitates the resetting operation.
[0081]
The number-of-photographs display plate 130 shown in FIG. 22 is provided with scale numbers from “0” to “25” on the surface thereof and appropriately arranged between them so that the number of photographed films of the photo film can be counted, for example, for 25 images. Are marked on the same circumference. A locking gear 133 is formed on the outer periphery of the number-of-photographs display plate 130 so as to mesh with the locking cam 132 of the camshaft 131. A step gear 135 meshed with the tooth gear 134 is formed integrally.
[0082]
Then, by rotating the cam shaft 131 in the counterclockwise direction in the figure by winding up one frame of the photographic film, the number-of-photographs display plate 130 is rotated clockwise by one division by the two-tooth gear 134, and the locking cam 132 Engages with the locking gear 133 during this rotation to prevent the displacement of the number-of-photographs display plate 130.
[0083]
Missing teeth without several teeth are formed on the locking gear 133 and the stepping gear 135 of the number-of-photographs display plate 130 so as not to interfere with the locking cam 132 and the two-tooth gear 134 of the cam shaft 131. Sections 137 and 138 are respectively formed. In the missing tooth sections 137 and 138, when the use of the lens-fitted photo film unit is completed and the photo film is entirely wound up in the cartridge, and the scale "0" is displayed in the center of the number-of-photographs display window 140. That is, at the end of the counting, it faces the locking cam 132 of the cam shaft 131 and the two-tooth gear 134.
[0084]
In the above state, when the number-of-photographs display plate 130 is forcibly rotated counterclockwise in the figure from the outside to engage the locking gear 133 and the stepping gear 135 with the locking cam 132 and the two-tooth gear 134, the scale The scale 142 indicating one frame for inspection arranged immediately before “25” is arranged at the center of the number-of-photographs display window 140, and the number-of-photographs display plate 130 has been reset.
[0085]
As described above, by partially providing the toothless sections 137 and 138 in the locking gear 133 and the stepping gear 135 of the number-of-photographs display plate 130, the number-of-photographs display plate 130 can be easily reset without disassembling the exposure unit. Can be performed.
[0086]
Also, as shown in FIG. 23, even if the missing tooth section 138 is provided only in the stepping gear 135, the number-of-photographs display plate 130 can be similarly reset. This is because the engagement amount between the locking gear 133 and the locking cam 132 is small, and the camshaft 131 is slightly released in a direction away from the number-of-photographs display plate 130 to rotate the number-of-photographs display plate 130 to the reset position. That's because we can. In this case, the number of teeth of the locking gear 133 of the number-of-images display plate 130 is larger than the number of teeth of the stepping gear 135 by several teeth. The reset of the number-of-photographs display panel due to the missing tooth section can also be used for the film counter mechanism of each of the above-described embodiments. In the case where a locking gear is provided on the lower surface thereof, the toothless section may be provided only on the stepping gear on the outer periphery of the number-of-photographs display plate.
[0087]
In each of the above embodiments, the film counter mechanism of the present invention is used for a film unit with a lens. However, the present invention can be used for a low-cost manual winding camera other than the film unit with a lens. In addition, the film counter mechanism that rotates once by transporting one frame of the photographic film and the film counter mechanism that rotates halfway have been described. The present invention can also be applied to a device that is rotated by ３ rotation, and further by １ ／ rotation.
[0088]
【The invention's effect】
As described above, the film counter mechanism of the present invention Since the teeth of the stepping gear are provided with a phase shift of less than half a pitch in the rotation direction of the number-of-photographs display plate with respect to the locking gear, , The amount of meshing of the drive gear becomes much larger . This allows The number-of-photographs display plate can be surely rotated by one scale without idling of the drive gear or the like. Also, after rotating the number-of-photographs display plate, Step gear Since the teeth of the drive gear can be easily removed from the teeth of the drive gear, the number-of-photographs display plate is not rotated extra.
[0089]
In addition, the shape of the drive gear is used when the Only stepping gear , So that the number-of-images display plate is not accidentally rotated due to rattling or the like when the drive gear is rotated.
[0090]
Further, when increasing the number of counts, the number-of-photographs display plate is used for locking, and a stepping gear is arranged below the number-of-photographs display plate. Can be increased, and the number of shots can be properly counted even with a long photographic film.
[0091]
In addition, since a toothless section having several teeth for facing the drive gear and releasing the meshing with the drive gear at the end of the count is formed on the outer periphery of the stepping gear, the missing tooth section is used. The number-of-photographs display plate can be forcibly rotated from the outside, and the film counter mechanism can be easily reused.
[Brief description of the drawings]
FIG. 1 is a plan view showing a state in which the number-of-shots display plate rotation of a film counter mechanism is started.
FIG. 2 is an external perspective view of a film unit with a lens embodying the present invention.
FIG. 3 is an exploded perspective view showing a configuration of a unit main body.
FIG. 4 is a front view schematically showing a relationship between a film counter mechanism and a photographic film.
FIG. 5 is a perspective view showing a configuration of a film counter mechanism.
FIG. 6 is a plan view showing a film counter mechanism at the end of rotation of the number-of-photographs display plate.
FIG. 7 is a perspective view showing a configuration of a film counter mechanism of another embodiment.
FIG. 8 is a perspective view showing an engaged state between a driven sprocket according to another embodiment and a photographic film.
FIG. 9 is a plan view showing a film counter mechanism at the start of rotation of the number-of-photographs display plate according to another embodiment.
FIG. 10 is a plan view showing a film counter mechanism at the end of the rotation of the number-of-photographs display plate according to another embodiment.
FIG. 11 is a perspective view showing a configuration of a film counter mechanism of still another embodiment.
FIG. 12 is a plan view showing a film counter mechanism of still another embodiment when not in use.
FIG. 13 is a plan view showing a film counter mechanism at the start of rotation of the number-of-photographs display plate according to still another embodiment.
FIG. 14 is a plan view showing a film counter mechanism at the end of the rotation of the number-of-photographs display plate according to still another embodiment.
FIG. 15 is a plan view showing a conventional film counter mechanism.
FIG. 16 is a plan view of a display panel for the number of shots according to still another embodiment.
FIG. 17 is a plan view showing a state immediately before a photographic film is wound in a film counter mechanism of still another embodiment.
FIG. 18 is a plan view showing a state in which a photographic film is being wound in a film counter mechanism according to still another embodiment.
FIG. 19 is a plan view showing a state immediately after the photographic film has been wound in the film counter mechanism of still another embodiment.
FIG. 20 is a diagram illustrating a state in which the number-of-photographs display plate according to still another embodiment is being conveyed, as viewed from below.
FIG. 21 is an enlarged view of a main part when a number-of-photographs display plate of still another embodiment is transported.
FIG. 22 is an explanatory diagram of a film counter mechanism with improved recyclability.
FIG. 23 is an explanatory view of another embodiment of a film counter mechanism having improved recyclability.
[Explanation of symbols]
2 Film unit with lens
13 Exposure unit
33,55 driven sprocket
34, 53, 88 Camshaft
35, 54, 90, 110, 130 Number-of-photographs display board
40,95 one tooth gear
40a, 95a, 69a protrusion
41, 70, 96, 132 Locking cam
46, 52, 133 Locking gear
69,134 Two-tooth gear
89,135 Stepping gear
137,138 Missing tooth section

Claims (5)

A number-of-photographs display plate rotatably supported with a number-of-photographs scale marked on its surface, a locking gear that is coaxially and integrally rotated with the number-of-photographs display plate and has a plurality of teeth formed on its outer periphery , A stepping gear formed on the outer periphery of the number-of-photographs display plate and having a plurality of teeth whose phases are shifted by less than half a pitch with respect to the locking gear in the rotation direction of the number-of-photographs display plate; A driven sprocket that is rotated by the transfer of the frame, a driving gear that rotates coaxially and integrally with the driven sprocket, meshes with the teeth of the stepping gear , and rotates the number-of-photographs display plate by one division, and the driving gear. A locking cam that is coaxially rotated integrally and prevents a rotation of the number-of-photographs display plate by partially inserting into one of the teeth of the locking gear while the driving gear is not meshed with the stepping gear; A film counter mechanism. 2. The film counter mechanism according to claim 1, wherein the drive gear has a shape that contacts the stepping gear only when rotating the number-of-photographs display plate. A number-of-photographs display plate which is rotatably supported with a number-of-photographs scale written on its surface, a locking gear formed on the outer periphery of the number-of-photographing display plate and having a plurality of teeth, and a lower portion of the locking gear A stepping gear having a plurality of teeth that are provided to be rotated coaxially and integrally and that are shifted in phase by less than half a pitch with respect to the locking gear in the direction of rotation of the number-of-photographs display plate ; A driven sprocket that is rotated by one frame of film transfer, a drive gear that is coaxially rotated with the driven sprocket, meshes with the teeth of the stepping gear, and rotates the number-of-photographs display plate by one division; Provided on the upper part of the drive gear, coaxially and integrally rotated, and while the drive gear is not meshed with the stepping gear, a part is inserted into one of the teeth of the locking gear to rotate the number-of-photographs display plate. It consists of a locking cam that blocks Film counter mechanism to be. 4. The film counter mechanism according to claim 3, wherein the drive gear is in contact with the stepping gear only when rotating the number-of-photographs display plate. The number-of-photographs display plate having a number-of-photographs scale marked on the surface thereof along the rotation direction, a step gear integrally formed with the number-of-photograph display plate , and a phase shifted from the step gear. A locking gear having teeth formed thereon, a driven sprocket which is rotated by one frame of the photographic film, and a coaxially rotated with the driven sprocket and meshed with the teeth of the stepping gear, thereby displaying the number-of-photographs display plate. A drive gear that rotates by one graduation, and is rotated coaxially and integrally with this drive gear, and while the drive gear is not meshed with the stepping gear, a part is inserted into one of the teeth of the locking gear, and the number of shots is taken. A locking cam for preventing the rotation of the display plate, a tooth provided at one or both of the outer circumference of the locking gear and the outer circumference of the stepping gear and used at the end of counting, and used at the start of counting. Of several teeth placed between In the reset process of the film counter mechanism and a free toothless section,
After the counting by the film counter mechanism is completed, the number-of-photographs display plate is forcibly rotated from the outside by using the missing tooth section, and the teeth used at the start of counting are set to one of the locking cam and the driving gear. Alternatively, a method of resetting the film counter , wherein both faces are faced .

Images