JPH03114034A - Camera - Google Patents

Abstract

PURPOSE:To prevent a film and a film introducing member from being strongly pressed to a film rail surface by providing a means which increases a gap between a pressure plate and the rail surface when a film is moved in an aperture part or the film is wound up. CONSTITUTION:A cover energizing lever 7 is pushed downward by the projecting part 2b of a back cover 2 and an operation lever 5 is energized counterclockwise by the tensile force of an accumulation energizing spring 8. However, an armature 6a is attracted and held by an electro-magnet 6 and the operation lever 5 is not turned counterclockwise. Then, the pressure plate 4 is at the position where it floats from the rail of a camera main body 1. Next, when the film is wound up to a spool 14, a film leader part 12 and the film introducing member are easily passed through the gap between the pressure plate 4 and the rail surface of the camera main body 1. Simultaneously with the finish of the winding up, the pressure plate 4 is pressed to the rail surface by the force of the energizing spring 8. Thus, the film and the film introducing member is easily passed through the gap between the pressure plate and the film rail surface without being caught by them.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a camera, and more particularly to an improvement of a film feeding device for a camera equipped with an automatic film loading device.

[Conventional technology]

2. Description of the Related Art Conventionally, many proposals have been made regarding so-called autoloading (hereinafter abbreviated as AL) devices and cameras equipped with such devices to facilitate film loading in cameras that use roll film. Some of these proposed technologies complete AL by simply closing the back cover after loading the cartridge into the camera, without manually setting the film leader. For example, after loading a cartridge into a camera and closing the back cover while leaving the film leader outside the camera, the device automatically unwinds the film.
A camera is known in which the film leader section is pulled into the camera and then the film is automatically wound.

In a camera equipped with the A-type device described above, when the film is unwinded, the film leader section passes through the aperture section from the cartridge chamber side to the spool chamber side, but the film leader section passes through the aperture section. There has been a drawback in that the tip of the film leader section tends to get caught in or fall into the aperture section when passing through the aperture section, making it impossible to pass through the aperture section.

Therefore, in order to eliminate this drawback, the present applicant has proposed an AL device having a film drawing member made of a flexible band-like member that is wound onto a spool together with a film leader portion. In an AL device equipped with this film drawing member, it is possible to completely prevent the film leader section from falling into or getting caught in the aperture section.

(Problems to be Solved by the Invention) However, even in the AL apparatus equipped with the above-mentioned film drawing member, there were the following problems that should be further improved.

In other words, the film running space in the aperture section of the camera is a narrow slit-shaped space between the rail surface and the pressure plate, and normally the pressure plate is biased by a spring toward the rail surface, and the space is Although it is set to be several tens of microns wider than the thickness of the film, if the film and the film attracting member try to pass through the slit-like space of this aperture section at the same time when performing empty winding using the film attracting member mentioned above, the film There was a risk that the film drawing member would be pressed against the rail surface by the spring force of the pressure plate.

In this way, when the film and film drawing member are pressed against the rail surface, the winding load torque increases rapidly during dry winding, and excessive load torque is also applied to the film winding mechanism and the film winding motor, causing the winding mechanism to Not only does this have a negative effect on the motor, but also a large amount of resistance is generated when the film leader section attempts to enter between the pressure plate and the rail surface. There was a risk of an accident in which excessive force was applied and the perforations were damaged.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide a camera configured so that the film and the film drawing member are not strongly pressed against the film rail surface at the aperture portion, for example, when the film is unwinded.

[Means to solve the problem]

The improved camera according to the present invention is characterized in that means is provided for increasing the distance between the pressure plate and the rail surface when the film moves through the aperture section or when the film is unwinded.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing an embodiment of the present invention, showing a camera viewed from below.

In the figure, 1 indicated by a broken line is the camera body, and 2 is the back cover. The back M2 is rotatably supported by a shaft 2a and includes a protrusion 2b.

3 is the rear cover, which is fixed to the camera body 1 and holds the pressure plate 4 with the spring 4.
It is maintained by a and 4b. Reference numeral 5 denotes a pressure plate operating lever, which is rotatably supported by a shaft 5a.

The operating lever 5 has one end engaged with the pressure plate 4 by a pin 5b, and the other end holds an armature 6a of an electromagnet 6 by a shaft 5C. The electromagnet 6 is a combination magnet consisting of a permanent magnet and a coil, and normally attracts and holds the armature 68 with the magnetic force of the permanent magnet, and releases the armature when the coil is energized.

Reference numeral 7 denotes a power storage lever, which is supported coaxially with the operating lever 5 by a shaft 5a. The energy storage lever 7 has a protrusion 2a on the back cover 2.
There are 18 parts that abut. Moreover, between the energy storage lever 7 and the operating lever 5, energy storage springs 8 are hung on pins 7b and pins 5d, respectively. A return spring 9 is hung between the pin 5e of the two-actuating lever 5 and the fixing pin 10.

11 is a cartridge, 12 is a film leader part, 13 is a film drawing member, and 14 is a spool. One end of the film drawing member 13 is fixed to the outer peripheral surface of the spool 14, and a film is formed at the other end of the member 13. The engaging protrusion engages with the perforation of the film leader section 12.

Next, the operation will be explained. The state shown in FIG. 1 shows a state in which a cartridge is loaded into the camera and the back cover 2 is closed. In this state, the protrusion 2a of the back M2 presses down the lid biasing barf, so the tension of the energy storage spring 8 causes the operating lever 5 to
is biased counterclockwise, but since the armature 6a is attracted and held by the electromagnet 6, the actuating lever 5 is held at the illustrated position without rotating counterclockwise.

In this state, the pressure plate 4 is in a position suspended from the rail of the camera body 1 by the operating lever 5.

When the camera user closes the back cover 2 with the film leader section left outside the camera after loading the cartridge, empty winding is automatically performed and the film leader section is drawn into the camera.

Thereafter, the film is automatically wound onto the spool 14 by a predetermined length together with the film drawing member 13, thereby performing empty winding. Note that when performing this blank winding, the pressure plate 4 is in a floating state with respect to the rail surface of the camera body 1 as described above, so the film leader section 12 and the film loading member 13 are connected to the pressure plate 4 and the rail surface of the camera body 1. can easily pass between.

When the film empty winding is completed in this way, the camera enters the ready state. During shooting, it is necessary for the pressure plate 4 to press the film against the rail surface of the camera body 1, so that the electromagnet 6
is energized, and as a result, the operating lever 5 is activated by the energy storage spring 8.
The force causes it to rotate counterclockwise.

FIG. 2 shows this state. In Figure 2,
Each number indicates the same thing as in FIG. In this state, the pressure plate 4 is pressed against the rail surface by the force of the energy storage spring 8, and therefore functions as a normal pressure plate. After shooting all frames of the film and rewinding the film, when the camera user opens the back cover 2 and takes out the cartridge, the energy storage lever 7 is pressed down by the protrusion 2a of the back cover 2. Since it is released from the position, it is rotated upward by the force of the energy storage spring 8,
As a result, the pin 7b comes into contact with the operating lever 5 and the lever 7
of! I] The movement stops.

In this state, the force of the spring 8 no longer acts on the actuation lever 5, so the action of the return spring 9 causes the actuation lever 5 and the accumulating lever 7 to rotate clockwise, and the armature 6
a is attracted to the electromagnet 6 again. As can be seen from the above explanation of the operation, the return spring 9 only needs to have enough force to rotate the actuating lever 5 in the no-load state, so the return spring 9 can be a very weak spring; The spring 8 needs to be strong enough to overcome the action of the spring 9.

3 and 4 show a second embodiment of the present invention. In addition, in Figures 3 and 4, Figures 1 and 2 are
The members indicated by the same numbers as in the figures are the same members as in the first embodiment, and therefore the description thereof will be omitted.

In the second embodiment shown in FIGS. 3 and 4, the operating lever 5 is the same as that in the first embodiment, but a plunger magnet 15 is used as the actuator for driving it. That is, when the armature 16 becomes slidable at the center of the plunger magnet 15 and the plunger magnet 15 is energized, the armature 16 is attracted and moved toward the left in the figure. The spring 17 is
It is hung between the pin 5e of the actuation lever 5 and the fixed pin 18, and urges the actuation lever 5 counterclockwise with a force weaker than the attraction force of the plunger magnet 15.

FIG. 3 shows a state in which the plunger magnet 15 is energized, and in this state, the pressure plate 4 is floating above the film rail surface of the camera body. FIG. 4 shows a state in which the plunger magnet 15 is de-energized,
In this state, the pressure plate 4 is pressed against the film rail surface, allowing normal maximum likelihood.

As described above, the feature of this embodiment is that the plunger magnet 15 is used as an actuator for operating the operating lever 5.
As a result, the pressure plate 4 can be freely moved back and forth by controlling the current flow to the plunger magnet 15 not only during empty winding but also during normal film feeding and rewinding. 9. The driving load during rewinding can be reduced.

〔Effect of the invention〕

As explained above, in the camera of the present invention, when the film passes through the aperture section, a means is provided to move the pressure plate backward with respect to the film rail surface, so that when the leading edge of the film is idly wound, the film and the film drawing member are The film easily passes through the space between the film rail surface and the pressure plate without getting caught on the pressure plate or the film rail surface, and the film easily passes through the space between the film rail surface and the pressure plate without getting caught on the film rail surface or the pressure plate during normal frame advance or return. Furthermore, during photographing, the pressure plate presses the film against the rail surface, thereby ensuring the flatness of the film surface.

[Brief explanation of drawings]

FIG. 1 is a plan view of the first embodiment of the camera of the present invention, showing a state in which the camera is loaded with a cartridge but has not yet started empty winding. 1
FIG. 3 is a plan view of the camera according to the embodiment in a state where the winding is performed without winding; FIG. 3 is a plan view of the second embodiment of the camera of the present invention; FIG. 4 shows a state in which the plunger magnet 15 is de-energized in the camera. 1... Camera body 2... Back cover 3... Back cover
4... Pressure plate 5... Pressure plate actuation lever 6.
...Electromagnet 6a... Armature 7... Energy storage lever 8... Energy storage spring 9... Return spring 10.
... Fixed pin 11 ... Cartridge 12 ... Film leader section 13 ... Film drawing member 14 ... Spool 15 ... Plunger magnet 16 ... Armature 17 ... Spring and other 4 people

Claims (1)

[Claims] 1. Before starting film winding, the film is stopped so as to extend along the film running path from the spool chamber to the cartridge chamber exit via the aperture, and when film winding starts, the film is wound onto the spool along with the film. After loading the flexible film loading member and the cartridge into the cartridge chamber, when the back cover of the camera is closed with the film leader section exposed outside the camera, empty rewinding is automatically performed. , a film running path in the aperture is formed between an autoloading means configured to automatically perform dry winding and the film rail surface of the aperture and the film rail surface of the aperture. What is claimed is: 1. A camera comprising: a pressure plate having an aperture; and means for increasing the distance between the pressure plate and the film rail surface when the film passes through the aperture.