JPH0755553Y2 - Camera film take-up spool - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an improvement of a film take-up spool of a camera.

BACKGROUND OF THE INVENTION Conventionally, in a film winding spool of a camera, a type in which a film is wound by providing a claw on the spool and engaging a perforation of the film with the claw to rotate the spool is generally known. .

6 to 7 show an example of this conventional film take-up spool, 1 is a camera body, 2 is a film take-up spool, and spool 2 is a lower part of a body portion 2e around which a film F is wound. And the perforation Fp of film F
Has a claw 2a for engaging with, and has a gear portion 2b for rotating by a motor (not shown) in the upper part of the moving portion 2e,
Further, a flange portion for guiding the film is provided below the gear portion 2b.
2c is formed. Reference numeral 3 denotes a film guiding flange which is provided at a lower portion of the body portion 2e so as to face the spool portion 2c at a distance from the spool portion 2c, and is formed to be slightly smaller than the inner diameter of the spool chamber 1b of the main body 1. As shown in FIG. 5, the claw-side flange 3 and the body portion 2e are formed separately. In FIG. 7, the flange 3 and the body portion 2e are formed separately, and the flange 3 on the claw side with respect to the outer diameter φA of the flange portion 2c in FIG.
When the outer diameter φB is increased to be integrally formed with the body portion 2e, the spool insertion hole 1a formed in the camera body 1 is formed with the same diameter φA as the outer diameter of the flange portion 2c. This is because the flange 3 on the side cannot pass through the spool insertion hole 1a, which makes assembly impossible. As a countermeasure, the inner diameter of the spool insertion hole 1a may be made the same as the outer diameter φB of the flange 3, but the camera body 1 becomes very weak in strength due to the large diameter of the spool insertion hole 1a. Also, since there is a large risk that light leakage will occur from the gap between the spool insertion hole 1a and the flange portion 2c, and the film of the photographic agent will be exposed, the body portion 2e and the flange 3 are separated. I was doing.

However, the body 2e and the flange 3 are separate bodies.

However, to separate the body 2e and the flange 3 from each other,
In terms of cost, two parts are required, and the barrel 2e is also attached to the spool insertion hole of the camera body 1 during assembly.
After inserting into the spool chamber 1b, insert the claw side flange 3 into the spool chamber 1b, and while fitting the body part 2e and the claw side flange 3 inside the camera, further insert the body part 2e into the lower hole of the camera body 1. It requires a great deal of work to fit it in. Also, because the flange 2c of the spool and the flange 3 on the claw side are separate parts,
It is difficult to control the dimensions between the flanges 2c and 3 on both ends, and the flanges on both ends firmly hold the film and the film F
However, there is a possibility that the basic purpose of the flange, which is to prevent the occurrence of so-called bamboo roll development, which is caused by touching in the thrust direction, cannot be achieved.

The regulation of the thrust direction of the film F by the pair of flanges 2c and 3 can be rolled up neatly by regulating 3 to 4 rolls at the beginning of film winding,
On the contrary, when the shake in the thrust direction occurs during the first 3 to 4 windings, the winding deviation of the film to be wound later is increased, and the bamboo shoot winding phenomenon described above is increased.

Therefore, in order to solve the above-mentioned problems of cost, assembling workability and dimensional control, as shown in FIG. 8, the flange 2d on the claw side is integrally formed with the body portion 2e, and the outer diameter φB 'of the claw is formed. A spool having the same diameter as or slightly smaller than the outer diameter φA of the flange 2c on the opposite side is proposed.

That is, since the flanges 2c and 2d are integrally formed at both ends of the body portion 2e, the cost can be reduced, and the spool 2 can be assembled from just above, and the dimension between the flanges at both ends is one. Therefore, management becomes easy. However, when such a spool is used, another problem may occur depending on the tip shape of the film F.

That is, as shown in FIG. 9, the leading end of the film F has a rounded corner R on the outside as a typical example.
Processed film [hereinafter referred to as F type (Fig. 9A)]
And a film having a rounded inner corner at the tip of the tip [hereinafter referred to as K type (FIG. 9B]). When loading a K type film on the spool 2 shown in FIG. As shown in FIG. 10, since the outer diameter of the flange 2d on the claw side is small, the leading end of the film rides on the outer peripheral portion of this flange 2d, even if the outer peripheral portion of this flange 2d is chamfered 2f. Even if the film is easy to fall to the body 2e side,
Since the tip corner of the K-shaped film is notched inward, this notch engages with the outer periphery of the flange 2d and rides up, resulting in the perforation of the film F.
In a camera that employs an auto-loading winding mechanism because Fp no longer engages with the claw 2a, the film perforation is performed after the back cover (not shown) of the camera body 1 is closed.
Since the Fp and the claw 2a are engaged to wind up the film for a plurality of frames, there arises a problem that the film cannot be wound up.

When F type film is used, even if the film rides on the flange 2d, the tip corners are round, so the film falls naturally along the chamfer 2f or into the body 2e by the pressure contact force of the auto loading mechanism (not shown). , Such problems hardly occur.

[Purpose of Invention] The present invention has been made in view of the above circumstances, and can reliably wind a film. An object of the present invention is to provide a film take-up spool for a camera which is inexpensive and can be easily constructed.

[Summary of the Invention] In order to achieve the above object, a film take-up spool of a camera of the present invention includes a rotatable body portion around which a film is wrapped, and a perforation of the film to be wrapped around the body portion. It is provided so as to project outwardly in the radial direction of the body part, which is outside of the body part and is approximately 90 degrees forward of the engagement part in the film winding direction of rotation, and which is fitted outside. The film has a protruding portion that swings off toward the engaging portion side as the body portion rotates.

[Embodiment of the Invention] Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings.

FIG. 1 is a perspective view showing an embodiment of a spool according to the present invention, and FIG. 2 is a sectional view taken along line AA of FIG.

The spool 20 according to this embodiment includes a body portion 20 around which a film is wrapped.
e, claw 20a with which the perforation of the film engages
The film guide flanges 20c and 20d are integrally formed, and the gear portion 20b meshing with a drive mechanism (not shown) such as a motor is fixed to the upper portion of the body portion 20e.
Then, the lower flange 20d on the side of the claw 20a extends radially outward from the outer peripheral surface of the body portion 20e and has an arcuate portion 20 having an outer diameter φB '.
A projecting portion 20g whose tip extends radially outward from the axial center of the body portion 20e to a distance c is projected in a part of h to form a planar egg shape. As shown in FIG. 2, the outer diameter φB ′ of the lower flange 20d is formed to be the same as or slightly smaller than the inner diameter of the spool insertion hole 1a of the camera body 1 as in the conventional example described above, and the protruding portion 20g is The length c is formed to be smaller than the radius D of the spool chamber 1b of the camera body 1.

However, by forming the lower flange portion 20d of the spool 20 into a flat egg shape, the spool 20 can be assembled to the camera body 1, and the perforation of the film can be nailed regardless of the shape of the tip corner of the film tip. The engagement with the 20a can be ensured.

That is, when the spool 20 is assembled to the camera body 1, the lower flange 20d can be passed through the spool insertion hole 1a of the camera body 1 by tilting the spool 20 as shown in FIG.

Further, when the front end of the film is placed on the barrel portion 20e for automatic loading, when the front end of the film is the K type shown in FIG. 10, the front end of the film is rotated when the spool 20 is rotated in the film winding direction. Even if one side of the part is riding on the arc part 20h, the film tip is largely shaken and bent by the protrusion 20g, and the notch of the film tip corner is not engaged with the outer periphery of the lower flange 20d. The elastic restoring force of the film itself causes it to fall into the body portion 20e, whereby the film is positioned at a position where the perforation Fp engages with the claw 20a, and the claw 20a and the perforation engage with each other to wind the film. .

As shown in FIG. 2, the claw 20a and the protrusion 20g of the lower flange 20d are separated from each other by an angle of about 90 ° in front of the claw 20a with respect to the traveling direction of the spool 20 in the winding direction. If the projection 20g is provided, the timing is good to hook the perforation of the film with the nail 20a immediately after the tip of the film falls into the body 20e, but this depends on the diameter of the spool 20 and the rotation speed. Once the leading edge of the film falls on the barrel 20e, the lower flange 2
Since it does not ride on the outer periphery of 0d, the lower flange 20d
There is no problem even if the protruding portion 20g is located at any position with respect to the claw 20a.

Further, as shown in FIG. 4, a chamfer 20f is provided on the outer peripheral surface of the lower flange 20d, and the chamfer 20f is formed so as to become gradually smaller toward the tip of the protruding portion 20g. When using, even if the notch at the corner of the film tip engages the outer periphery of this lower flange 20d,
When the spool 20 rotates, the film front edge is lowered to the lower flange 20.
Body 20e as moving from arcuate part 20h of d to protrusion 20g
Since it is moved to the side, the leading end of the film can be easily dropped into the body portion 20e.

Also, depending on the camera, not only when the spool 20 is wound up, but also when the film is rewound, the spool is reversed to feed out the film.In this case, the spool 20 is rotated around the body 20e of the spool 20. If the wound film sags and turns into a so-called "bukka winding", the rotation of the spool 20 and the rotation of the film may be different, and the film may rub against the flange of the spool, so as shown in FIG. 5, the protrusion 20g of the lower flange 20d The resistance at the time of rewinding can be reduced by subjecting the outer peripheral portion, especially the front surface 20i in the traveling direction of the rewinding direction (indicated by the broken line arrow in the drawing) to chamfering or R-processing on the traverse.

The protruding portion 20g does not have to have an oval shape and may have a shape as shown in FIG. In this case, since the large-diameter flange portion having the radius C is large, the probability itself that the leading edge of the film runs on the small-diameter flange as shown in FIG. 10 can be lowered.

(Correspondence between the device and the embodiment) In the above embodiment, the body portion 20e is the body portion of the present invention and the claw 2
0a corresponds to the engaging portion of the present invention, and the protrusion 20g corresponds to the protrusion of the present invention.

[Advantages of the Invention] As described above, according to the present invention, a film winding spool of a camera capable of reliably winding a film can be easily configured at low cost.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a spool according to the present invention, FIG. 2 is a sectional view taken along line AA of FIG. 3, FIG. 3 is a view showing how to assemble it, and FIGS. FIG. 6 is a perspective view of another embodiment of the flange, FIG. 6 is a perspective view showing a state in which a conventional spool is assembled to a camera, FIG. 7 is its sectional view, and FIG. 8 is a sectional view of another conventional spool. 9 (A) and 9 (B) are plan views of the leading end portion of the film, and FIG. 10 is a plan view showing a state where the leading end portion of the film rides on the flange of the spool.
FIG. 11 is a view similar to FIG. 2 showing still another embodiment. 20: Spool, 20a: Claw 20c, 20d: Flange, 20e: Body 20g: Projection, 20h: Arc

Claims (1)

[Scope of utility model registration request] 1. A rotatable body portion around which a film is wound,
An engaging portion that is provided on the body portion and that engages with the perforation of the film to be wrapped, and the body portion outside the body portion with respect to the engaging portion and at the front of the engaging portion approximately 90 degrees in the film winding rotation direction. And a projecting portion which is provided so as to project outward in the radial direction of the portion, and which swings down the film that has climbed up to the side of the engagement portion as the body portion rotates, spool.