JPH0527317A - Camera - Google Patents

Abstract

PURPOSE:To prevent the leading edge part of a film from being buckled or damaged at the position of a sprocket. CONSTITUTION:Position set means 15 and 16 which are arranged between the sprocket 7 and a cartridge chamber 22, which rotate the sprocket 7 by interlocking with the traveling of the film 2 before the leading edge part of the film 2 arrives at the position of the sprocket 7 when the film 2 is idly fed and position the tip part of the tooth part 7a thereof to the outside of the traveling locus of the film are provided. When the leading edge part of the film arrives at the position of the sprocket 7, the tip part of the tooth part of the sprocket 7 is made to escape to the outside of the traveling locus of the film so as to prevent the leading edge part of the film from abutting on the tip part of the tooth part of the sprocket.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roller member that is pressed against a film surface and receives a driving force as the film is fed by frictional force to rotate, and a roller member that rotates integrally with the roller member. A shape having a first rotation range in which the teeth rotate while engaging with the perforation of the film and a second rotation range in which the teeth rotate without engaging the perforation. The present invention relates to an improvement of a camera using a film having a large perforation (however, at least one film is provided per one screen) having a sprocket and a sprocket.

[0002]

2. Description of the Related Art In a conventional camera, there are the following film feed amount detecting means for feeding a fixed length of film.

1) Using a roller member pressed against the film, and detecting the amount of rotation of the roller member with the feeding of the film by means of a pulse plate, etc. 2) Perforation of the film by means of a photoreflector, etc. −
However, each of the above 1) and 2) has the following drawbacks.

In the above 1), an error occurs due to the slip between the roller and the film, and as a result, the error is accumulated and a large error occurs.

In the above item 2), it is necessary to provide a photodetector such as a photoreflector and a drive circuit for the photodetector, so that the cost of the camera is increased. Further, the control circuit of the camera for controlling them becomes expensive and complicated. Furthermore, since the film feed amount cannot be mechanically output, the counter for the number of film frames cannot be a mechanical counter, and a counter using a liquid crystal display or the like must be used. This leads to higher costs.

Further, there are the followings which can eliminate these drawbacks.

3) Using a sprocket having teeth meshing with the perforation of the film and detecting the amount of rotation of the sprocket with the feeding of the film by a pulse plate or the like. It had such drawbacks.

This point will be described with reference to FIG.
In FIG. 17, the pitch of the perforation P (which corresponds to the pitch of one frame of the film) is L, the radius of the root circle of the sprocket 101 excluding the tooth portion 101a is B, and the tooth of the tooth portion 101a is When the length is A, the outer diameter of the sprocket 101 is “A + B”, but “A + B” must satisfy at least the relationship of (A + B) ² ≧ B ² + (L / 2) ² . From this,
The outer shape of the sprocket 101 is "L / 2" or more. Therefore, when a film having a large pitch L of perforations P is used, the sprocket 101 becomes large.

Therefore, the applicant of the present invention has a roller which is pressed against the surface of the film and receives a rotational driving force due to the feeding of the film due to a frictional force, and the roller which can rotate integrally with the roller and which is a part of the film. A prior application of a camera provided with a sprocket having teeth capable of engaging with a foreground (Japanese Patent Application No. 3-10636).
No. 2) As a result, the diameter of the sprocket can be freely set. That is, the sprocket can be made small. Therefore, it is possible to achieve a compact camera.

[0010]

However, the structure of the above-mentioned 3) has the structure of the film cartridge proposed in U.S. Pat. No. 4,834,306 (that is, the rotation of the supply spool in the film cartridge). A camera of a type in which a film is extruded and is fed to a camera by means of (for example, Japanese Patent Laid-Open No. 2-67535). No. 2, Japanese Patent Application No. 2-200573, etc.),
Alternatively, when a normal film is used in a camera which feeds the film to a film winding spool of the camera with a roller having a driving force, the following problems occur. I had. This will be described below with reference to FIG.

That is, the leading end portion 202a of the film 202
When the tooth portion 201a of the sprocket 201 is within the traveling locus of the film 202 when the sprocket 201 moves toward the spool chamber of the camera, after rotating the sprocket 201, the
Although it advances to the lathe portion (not shown), if the tip portion of the tooth portion 201a of the sprocket 201 is at the position as shown in FIG. 202a is a tooth portion 20 of the sprocket 201.
1a, the friction force generated on the contact surface and the film 202 causes the tooth portion 201 of the sprocket 201 to contact.
Depending on the direction of the force pushing a, etc., the sprocket 201
In some cases, the film cannot be rotated, the film 202 is prevented from moving, the film 202 buckles, and the film cannot be fed thereafter, or the film is damaged.

In view of the above points, an object of the present invention is to provide a camera capable of preventing the leading end of the film from buckling or being damaged at the position of the sprocket.

[0013]

DISCLOSURE OF THE INVENTION The present invention is arranged between a sprocket and a cartridge chamber, and is interlocked with the running of the film before the leading end of the film reaches the position of the sprocket when the film is idly fed. There is provided position setting means for rotating the sprocket to position the tip end of the tooth portion thereof outside the film traveling locus.

[0014]

When the film leading end reaches the position of the sprocket, the position setting means allows the leading end of the tooth to escape from the film traveling locus so that the leading end of the film does not contact the leading end of the tooth of the sprocket. I have to.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a perspective view showing the structure of the essential parts of a first embodiment of the present invention.

In FIG. 1, 1 is a film cartridge and 2 is a film having perforations 2a and 2b. In the present embodiment, it is assumed that there is only one perforation for the length of one frame of film in order to easily understand this feature. That is, when the aperture size is "36 mm", the pitch of one frame is "38 mm" because the screens do not overlap. Therefore, the pitch L between the perforations 2a and 2b is also "38 mm".

A roller 3 is rotatably arranged on a camera body (not shown) so as to receive a rotational force as the film 2 travels, and a position 4 opposes the roller 3 with the film 2 interposed therebetween. Further, a pressing roller 5 rotatably attached to a portion 5a of a pressing lever 5 to be described later is a pressing lever 5 rotatably attached to a camera body (not shown) at a portion 5b, and one end of a pressing lever 6 is provided. It is fixed to the camera body (not shown), and the other end is pressed down and the lever 5
Is a spring for attaching the pressing lever 5 to the counterclockwise direction and pressing the pressing roller 4 against the roller 3 attached to the arm 5c of the roller.

Reference numeral 7 is a sprocket, and the roller 8 is attached by a shaft 8.
It is fixed to the shaft 8 so as to rotate integrally therewith. 9
Is a disk and is fixed to the shaft 10 so as to rotate integrally with the roller 3 and the sprocket 7 by the shaft 10. 1
Reference numeral 1 denotes a pulse base having a conducting portion 11a and a non-conducting portion 11b, which is fixed to the disk 9. Reference numerals 12 and 13 denote pulse contacts that generate pulse signals associated with the rotation of the pulse board 11. The pulse signals generated here are output to a control circuit that controls various operations of the camera (not shown) to rotate the pulse board 11. Processed as a signal to detect quantity. Reference numeral 14 is a first gear which is fixed coaxially with the roller 3 and is rotatable integrally with the roller 3.

A large-diameter portion 1 is capable of contacting the film 2 and receives a rotational driving force as the film 2 travels at the time of contact.
5a and a small-diameter portion 15b that cannot come into contact with the film 2, which is an initial roller, and is rotatably attached to a main body (not shown). Reference numeral 16 denotes an initial pressing roller rotatably attached to a portion 17a of an initial pressing lever 17 described later at a position facing the initial roller 15 with the film 2 interposed therebetween.
La, 17 is an initial pressing lever rotatably attached to a main body (not shown) at 17b, and 18 is attached to the main body (not shown) at one end and to the arm 17C of the initial pressing lever 17 at the other end. A spring for applying a biasing force to the initial pressing lever 17 in the clockwise direction to press the film 2 against the initial pressing roller 15 via the initial pressing roller 16. 21 is a stopper provided on the main body (not shown),
The position of the initial pressing lever 17 in the right rotation direction is regulated.

Reference numeral 19 denotes a second gear which is coaxial with the initial roller 15 and is rotatable integrally. The first gear 14 and the second gear 19 have the same number of teeth. 20 is the first gear 14
Is a connecting gear that meshes with the second gear 19 and transmits the rotation of the second gear 19 to the first gear 14. Reference numeral 22 is a cartridge chamber in which the film cartridge 1 is loaded, and reference numeral 23 is attached by a known means (for example, Japanese Patent Application No. 1-344801) while maintaining a predetermined gap with a film rail surface (not shown). It is a film pressure plate.

Here, the film cartridge 1 used in this embodiment is of the type proposed in the above-mentioned US Pat. No. 4,834,306, and the supply cartridge (not shown) in the film cartridge 1 is used. The film 2 is extruded from the inside of the film cartridge 1 by the rotation of the reel and is fed.

In the above construction, as shown in FIG. 2, when the tip end of the tooth portion 7a of the sprocket 7 is located within the traveling locus of the film 2, the large diameter portion 1 of the initial roller 15 is formed.
The phase relationship between the sprocket 7 and the initial roller 15 is such that the film 5a comes into contact with the film 2.

When the film cartridge 1 is loaded in the cartridge chamber 22 as shown in FIG.
The film 2 is extruded from the inside of the film cartridge 1 by a known film feeding gear train such as 534, and the film 2 is fed through the gap between the film pressure plate 23 and the main body, and the leading end of the film is initially moved. Large diameter part 15 of roller 15
It enters between a and the initial pressing roller 16 against the urging force of the spring 18. Further, when the film is fed, the initial roller 15 is accordingly moved to the large diameter portion 15
Since a receives the rotational driving force due to the frictional force, it rotates clockwise. At that time, the second gear 19, the coupling gear 20, the first gear 1
4 The sprocket 7 etc. are also rotated, and the sprocket 7 rotates clockwise. This state is shown in FIG.

When the film 2 is further fed and the initial roller 15 is rotated, the large diameter portion 15a faces the film 2 from the large diameter portion 15a to the small diameter portion 15b (see FIG. 4).
The initial roller 15 and the film 2 do not come into contact with each other and do not receive the rotational driving force. At this time, the tooth portion 7a of the sprocket 7 has escaped from the running locus of the film 2 as shown in FIG. Thereafter, the sprocket 7 does not receive the rotational driving force until the film 2 is fed and enters between the roller 3 and the pressing roller 4 against the urging force of the spring 6.

Further, when the initial roller 15 is rotated rightward from the rotational position shown in FIG. 4 to the rotational position shown in FIG. 5, that is, when the small diameter portion 15b is in the rotational position facing the film 2, Although the rotational driving force is not received, in that case, the tooth portion 7a of the sprocket 7 is in a state of escaping to the outside of the traveling path of the film 2, so that the rotational position of the sprocket 7 before the film cartridge 1 is loaded. Regardless of the sprocket, when the film 2 is pushed out from the film cartridge 1 and the tip of the film reaches the position shown in FIG. 4, that is, the position just before entering the rotation locus of the tooth portion 7a of the sprocket 7, the sprocket will be The tooth portion 7a of 7 is the film 2
There is no possibility that the film 2 escapes from the traveling locus, the film tip abuts against the teeth 7a of the sprocket 7 and bulges, further feeding is prevented, and the film 2 buckles at that position. ..

After that, the leading end of the film is fed between the roller 3 and the pressing roller 4 against the urging force of the spring 6 and fed.

With respect to the subsequent operation, the roller 3, the sprocket 7 and the pressing roller will be described with reference to FIGS. 6 to 10.
6 to 10 using only the la 4, the pressing lever 5, the spring 6, and the film 2 (for simplification of the drawing). The initial roller 15 always rotates in conjunction with the roller 3.

As the film 2 is further fed from the state shown in FIG. 4, the roller 3 is rotated rightward as the film 2 is fed by the frictional force generated by the urging force of the spring 6. Further, the sprocket 7 configured to rotate integrally with the roller 3 also rotates to the right. When the tooth portion 7a of the sprocket 7 comes into contact with the film 2 surface as shown in FIG. 6, these rotations are prevented, but the film 2 slips on the roller 3 surface. The film 2 is fed.

When the film 2 is further fed, the perforation 2a comes to a position where it can engage with the tooth portion 7a, and as shown in FIG. 7, the tooth portion 7a and the perforation portion 2a.
It comes to engage with a. After that, since the perforation 2a and the tooth portion 7a are engaged, the roller 3 and the sprocket 7 rotate as shown in FIG. 8 as the film 2 is fed. Then, up to the position where the engagement between the perforation 2a and the tooth portion 7a shown in FIG. 9 is released,
The sprocket 7 and the film 2 are positioned and rotated to advance the film feeding. However, after the engagement between them is released, the roller 3 is rotated by the frictional force generated by the urging force of the spring 6 again. To go.

Assuming that the diameter of the roller 3 is D and the distance between the perforations 2a and 2b is L, "D × π <
Because of the L relationship, the sprocket 7 is in a position where the tooth portion 7a abuts the film 2 surface before the next perforation 2b reaches the position where the tooth portion 7a can be engaged. Rotate up to. FIG. 10 shows this state. After that, even if the film 2 is fed until the next perforation 2b comes, the roller 3 only slips on the surface of the film 2 and the roller 3 and the sprocket 7 do not rotate.

By the way, from the state of FIG. 9 to the state of FIG. 10, the roller 3 has some slip on the surface of the film 2, and the feed amount of the film 2 and the rotation amount of the roller 3 are exactly the same. Even if the diameter D of the roller 3 is set to be sufficiently smaller than "L / π", the tooth portion 7a comes into contact with the film 2 surface before the next perforation comes. .. Then, the next perforation is engaged with the tooth portion 7a to reposition the perforations of the sprocket 7 and the film 2, so that the rotational error of the roller 3 is not accumulated.

11 to 15 show a second embodiment of the present invention.

In this embodiment, as shown in FIG. 11, the roller 3, the pressing roller 4, the pressing lever 5 and the spring 6 are removed from the first embodiment, and instead, The initial roller 15 has a circumferential portion 15a capable of contacting the film 2 and a flat surface portion 15b not in contact with the film 2, and the phase of the initial roller 15 and the sprocket 7 is set as follows. I am doing it. That is, the flat portion 15b is located at a position facing the film 2,
When it is in a position where it is not directly subjected to the rotational driving force due to feeding, the tip end of the tooth portion 7a of the sprocket 7 escapes to the running trajectory of the film and is securely engaged with the perforation of the film 2. The position is set to

In the above structure, when the film cartridge 1 is loaded into the cartridge chamber 22, the film 2 is extruded from the film cartridge 1 and the leading end of the film is fed to the position of the initial roller 15. Will be sent. FIG. 12 shows a state before the leading edge of the film reaches the initial roller 15.

At this time, when the flat portion 15b of the initial roller 15 is not in a position facing the film 2, that is, when the circumferential portion 15a is in a position where it can contact the film 2, the film feeding force causes The film 2 gets into the space between the initial roller 15 and the initial pressing roller 16 to make the initial roller.
Rotate La 15 to the right. Then, as shown in FIG. 13, when the flat portion 15b of the initial roller 15 comes to a position facing the film 2 and does not come into contact with the film 2, naturally, the rotational driving force is not received. At this time, the tooth portion 7a of the sprocket 7 is in a rotational position in which the leading end of the tooth portion 7a escapes from the running trajectory of the film 2 and the leading end portion of the film 2 contacts the side surface of the tooth portion 7a.

When the flat portion 15b of the initial roller 15 is located at a position facing the film 2 in advance, the film cartridge 1 is loaded into the cartridge chamber 22 and then the film 2 is fed. As it goes, the initial roller 15 does not rotate, and the tooth portion 7a of the sprocket 7 is naturally in the state shown in FIG.

When the film 2 is further fed from the state shown in FIG. 13, the leading end of the film is the tooth portion 7 of the sprocket 7.
Since it abuts against the side surface of a, the sprocket 7 is not stretched here during film travel, and the sprocket 7 is rotated as the film travels. Then, as shown in FIG. 14, before the engagement between the tooth portion 7a of the sprocket 7 and the film 2 is disengaged, the circumferential portion 15a of the initial roller 15 comes into contact with the film 2 and comes to a position for receiving the rotational driving force. ..

When the film 2 is further fed and the tooth portion 7a of the sprocket 7 is disengaged from the film 2, the rotational driving force received by the circumferential portion 15a of the initial roller 15 causes
The initial roller 15, the sprocket 7, the connecting gear 20, etc. rotate. Then, as shown in FIG.
The teeth 7a of the sprocket 7 come into contact with the surface of the film 2 before the operation 2a arrives, and enter the engagement standby state. After that, the film 2 is fed while slipping on the circumferential portion 15a of the initial roller 15, and when the perforation 2a of the film 2 reaches a position where it can be engaged with the teeth 7a of the sprocket, the initial roller 15 is moved. -The tooth driving portion 7a of the sprocket 7 is engaged with the perforation 2a by the rotational driving force received by the circumferential portion 15a of the roller 15.

FIG. 16 is a plan view showing the structure of the main part of the third embodiment of the present invention.

This embodiment differs from the first embodiment in that the initial roller 15, the initial pressing lever 17 and the spring 1 are used.
Instead of removing 8, the second gear 19, the connecting gear 20, and the first gear 14, the following members are provided.

In FIG. 16, reference numeral 23 is a pin provided on the sprocket 7, and 24 is an initial lever which is rotatably attached to a main body (not shown) with a portion 24a as a rotation center. 25 is a main body (not shown) at one end and an initial lever 24 at the other end
A spring, which is attached to the initial lever 24 and applies a biasing force to the initial lever 24 for clockwise rotation, is a stopper provided on a main body (not shown), which can come into contact with the arm 24d of the initial lever 24. The position of -24 in the clockwise direction is restricted.

When the film 2 is fed from the state shown in FIG. 16, the leading end of the film abuts on the arm 24b of the initial lever 24, and resists the biasing force of the spring 25, and the initial lever 24.
Rotate counterclockwise. At that time, in the arm 24c, the arm 24c
If the pin 23 is located within the rotation locus of the sprocket 7, the pin 23 is pushed to rotate the sprocket 7, and the tip of the tooth portion 7a of the sprocket 7 is released outside the traveling locus of the film. Pin 23 accompanying rotation of 7
Retract outside the rotation trajectory of.

Even with this configuration, the tip of the film does not come into contact with the tip of the tooth portion 7a of the sprocket 7,
The same effects as those of the first and second embodiments can be obtained.

According to each of the above embodiments, the camera sp
When the film 2 is fed to the chamber, before the tip of the film reaches the sprocket 7, the tooth portion 7a of the sprocket 7 is
Since the leading end of the film is made to escape from the trajectory of the film, the leading end of the film comes into contact with the tooth portion 7a of the sprocket 7 to prevent further progress, and the film is buckled or damaged at this position. There is no such thing as being lost.

[0045]

As described above, according to the present invention,
The sprocket is arranged between the sprocket and the cartridge chamber, and before the film front end reaches the position of the sprocket when the film is idly fed, the sprocket is rotated in association with the running of the film, and the front end of the tooth portion thereof. Is provided outside the film travel locus, and when the film tip reaches the position of the sprocket, the tip of the tooth is set so that the tip of the film does not contact the tip of the tooth of the sprocket. I try to escape to the outside of the running track. Therefore, it is possible to prevent the leading end of the film from buckling or being damaged at the position of the sprocket.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main configuration of a first embodiment of the present invention.

FIG. 2 is a plan view showing a positional relationship of each member in FIG. 1 before film feeding.

FIG. 3 is a plan view showing a state immediately after starting film feeding from the state of FIG.

FIG. 4 is a view showing that the film is fed from the state shown in FIG.
FIG. 7 is a plan view showing a state when passing through a la position.

5 is a plan view showing a positional relationship before the film is fed, which is different from that of FIG. 2 of each member of FIG. 1. FIG.

FIG. 6 is a partially omitted plan view showing a state in which the film has advanced from the state of FIG. 4 and has passed the position of the roller.

FIG. 7 is a partially omitted plan view showing a state in which the tooth portion of the sprocket is engaged with perforation due to the progress of film feeding from the state of FIG.

FIG. 8 is a partially omitted plan view showing a state in which the film feeding is advanced from the state of FIG. 7 in a state where the teeth of the sprocket and the perforations are engaged with each other.

9 is a partially omitted plan view showing a state in which the film feeding is advanced from the state of FIG. 8 until just before the engagement between the tooth portion of the sprocket and the perforation is released.

FIG. 10 is a partially omitted plan view showing a state in which the film feeding is further advanced from the state of FIG. 9 and the tooth portion of the sprocket has reached a position where it can be engaged with the next perforation.

FIG. 11 is a perspective view showing the configuration of the main part of the second embodiment of the present invention.

FIG. 12 is a plan view showing the positional relationship of the respective members of FIG. 11 immediately after the film is fed.

FIG. 13 is a plan view showing a state in which the film feeding has advanced from the state of FIG. 12 and has passed the position of the initial roller.

FIG. 14 is a plan view showing a state in which the film feeding advances from the state of FIG. 13 and the leading end of the film pushes the tooth portion of the sprocket.

FIG. 15 is a plan view showing a state in which the film feeding is further advanced from the state of FIG. 14 and the teeth of the sprocket have reached a position where they can be engaged with the perforations.

FIG. 16 is a plan view showing the configuration of the main part of the third embodiment of the present invention.

FIG. 17 is a diagram for explaining a conventional sprocket.

FIG. 18 is a diagram for explaining a problem that a sprocket having a toothed portion previously filed by the applicant of the present application has.

[Explanation of sign]

 1 Film Cartridge 2 Films 2a, 2b Perforation 3 Roller 7 Sprocket 7a Teeth 14 First gear 15 Initial roller 16 Initial pressing roller 19 Second gear 20 Coupling gear 22 Cartridge Chamber 23 pin 24 Initial lever

Claims (1)

Claim: What is claimed is: 1. A roller member, which is pressed against a film surface and receives a driving force as the film is fed by a frictional force to rotate, and a roller member which rotates integrally with the roller member, In the one-frame feeding of the film, the tooth portion engages with the perforation of the film to rotate and the tooth portion has the first rotation range.
In a camera including a sprocket having a second rotation range in which the sprocket and the cartridge chamber accommodate a film cartridge, the sprocket and the cartridge chamber are provided. And the front end of the film is moved to the position of the sprocket during the idling of the film, and the sprocket is rotated in conjunction with the traveling of the film to position the front end of the tooth portion outside the film traveling locus. A camera provided with a position setting means for controlling the position.