JPH0710341Y2 - Lens filter mounting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a device for mounting a lens filter of a camera.

(Prior Art) Conventionally, a lens filter (hereinafter simply referred to as “filter”) is used for adjusting a color tone by correcting light when shooting with a camera, or for blocking an ultraviolet ray and protecting a shooting lens. There is. In particular, if you want to delicately correct the light and obtain the desired color tone, compare with a glass filter,
It is often the case that a number of gelatin filters, which have excellent optical characteristics, a wide variety of color tones, and small thickness and weight, are stacked and used. The filter is generally attached to the front side of the taking lens, but it is also known that the holder is installed behind the taking lens and the filter is inserted into it.
This protects the filter from fingerprints, moisture, dust, etc., while maintaining the function of the gelatin filter that is particularly susceptible to these, and prevents harmful reflections that often occur when the filter is placed in front of the taking lens. I try to get the advantages such as.

(Problems to be Solved by the Invention) However, since the conventional filter holder has a constant size and is configured to be directly attached to the lens board, the attachment itself may depend on the size of the taking lens. However, there is a problem in that it is difficult to attach it, or it cannot be attached at a desired position in the front-rear direction.

That is, there are various kinds of photographing lenses to be used, and thereafter, the outer diameter and axial length of the ball are extremely wide, and for example, those having an outer diameter of 30 to 100 mm and an axial length of 10 to 100 mm are used. Therefore, when the outer diameter of the rear lens is relatively large with respect to the lens board, a sufficient space cannot be secured in the lens board, and the filter holder cannot be attached. Further, since the axial length of the holder is constant, if the rear lens has a large axial length as compared with this, it becomes difficult to mount the holder.
Conversely, if the axial length of the rear lens is small, the holder can be attached, but the filter cannot be installed in the desired axial direction, for example, if the axial length of the rear lens is too small,
The distance between the rear lens and the filter becomes too large, which limits the depiction range of the lens.

Further, the above-mentioned conventional holder is configured such that when a plurality of filters are used, they are inserted in parallel with each other. In order to avoid sticking, it is necessary to insert the filter body set in a mount made of cardboard etc., this set is costly and time consuming, and the thickness of the mount increases as the mount increases. There is also the drawback that the axial length of the holder becomes large.

The present invention has been made to solve the problems of the above-mentioned conventional techniques, and regardless of the size of the taking lens,
It is an object of the present invention to provide a lens filter mounting device capable of easily mounting a lens filter at a desired position.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a lens filter holder on the rear side of the lens board of the photographing lens in which a front lens and a rear lens are mounted with a lens board interposed therebetween. In the provided lens filter mounting device, the holder is configured to be extendable in the front-rear direction.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a state in which the holder of the lens filter according to the present invention is attached to the taking lens, and the taking lens 1 is the front lens 2
And the rear ball 3. The front lens 2 is attached to the lens board 4 by fitting the rear end of the front lens 2 into a hole in the center of the lens board 4 and screwing the inner screw 5a of the mounting member 5 into the outer screw 2a of the rear end. Also, the rear ball 3 has its outer screw
It is integrated with the front lens 2 by screwing 3a into the inner screw 2b at the rear end of the front lens 2. On the rear side of the mounting member 5, a disk portion 5b having a larger diameter than the front side is formed.

2 to 5 show a lens filter holder according to the present invention. In this embodiment, this holder comprises a front frame 6, a rear frame 7 and a holding frame 8 which are substantially square and face each other. Two side surfaces of the front frame 6 and the rear frame 7 are connected by two connecting members 9, 9 (see FIG. 2). That is, one connecting member 9 has one end rotatably connected to the lower end of the front frame 6 by the pin 10 and the other end provided with the long groove 11 and the pin 12 provided along the upper side surface of the rear frame 7. Is slidably engaged via. The other connecting member 9 also connects between the lower end portion of the rear frame 7 and the long groove 11 at the upper portion of the front frame 6 in the same manner, and the pin 13 is located where the connecting members 9 intersect.
Are rotatably connected to each other.

At the center of the front surface of the lower side portion of the front frame 6, a plate-shaped first holder attachment tool 14 along the longitudinal direction thereof is screwed at two places via washers 15. Also, the front frame 6
At the center from the front surface to the upper surface of the upper part of the second holder attachment 16 having an L-shaped cross section along the longitudinal direction thereof,
It is screwed at two points via washers 17. The hole (not shown) of the second holder attachment 16 for this screwing is formed as an elongated hole extending in the up-down direction, so that the second holder attachment 16 extends along this elongated hole. It can be moved up and down. In addition, the distance L between the edges of the holder attachments 15 and 16 on the opposite sides.
Is slightly larger than the diameter of the disc portion 5a of the mounting member 5 at the first position (the one-dot chain line in FIG. 1) where the second holder mounting member 16 is located at the uppermost position, and is located at the lowermost position. Second
Is set to be slightly smaller at the position (solid line in FIG. 1).

The holding frame 8 has a size corresponding to the front frame 6 and the rear frame 7 and is formed in a substantially square shape. The lower portion of the holding frame 8 is provided with pins 18 on both sides of the lower portion of the holding frame 8 so that there is some play in the front-rear direction and the up-down direction.
Is fastened to the rear surface of the rear frame 7 and can be opened and closed with respect to the rear frame 7. The upper portion of the holding frame 8 is fixed to the rear frame 7 by being sandwiched together with the rear filter 7 in the groove portions of two levers 19 rotatably attached to the rear frame 7 and having a substantially U-shaped cross section. Has become. Both sides 8a of the holding frame 8 are made of an elastic material having a weak elasticity, and when not fixed to the rear frame 7, as shown in FIG. Guide pins 20 projecting rearward are provided at two positions in the vertical direction on the back surfaces of both sides of the rear frame 7.

Next, the operation of the lens filter mounting device having the above configuration will be described.

When attaching the holder to the taking lens, first, the second holder attachment 16 is lifted to the first position, and then the first holder attachment 15 and the lower front surface of the front frame 6 are separated. Engage the lower edge of the disc portion 5b of the mounting member 5 in between, and further push down the second holder mounting member 16 to the second position, and then the second holder mounting member 16 and the upper portion of the front frame 6. The upper edge of the disk portion 5b of the set ring 5 is engaged with the front surface (see FIG. 5). Since the holder is thus attached to the disc portion 5b of the mounting member 5, the disc portion 5b
Is set to a size corresponding to the maximum outer diameter of the rear lens 3 to be used, the holder can be attached regardless of the size relationship between the rear lens 3 and the lens board 4. Alternatively, a plurality of types of mounting members 5 having different outer diameters of the disc portion 5b may be prepared and used properly according to the outer diameter of the rear ball 3.

The attachment of the holder to the attachment member 5 is not limited to the above-mentioned method, but can be performed by another method, for example, by providing a screw on both the attachment member and the holder and screwing them together. Attach both holder attachments 15, 16 to the disk part 5b.
Since it is engaged with, the position in the circumferential direction can be freely selected at the time of mounting, and therefore, the holder can be mounted in a predetermined circumferential position regardless of the stop position of the rear ball 3 in the circumferential direction. The advantage is that

Further, since the front frame 6 and the rear frame 7 are connected by the connecting member 9 according to the above-described configuration, both the frames 6 and 7 are attached before the holder is attached, and the rear frames are attached after the holder is attached. By pushing or pulling the frame 7, the connecting member 9 is rotated around its lower end while the upper end is guided by the long groove 11 to move, and the holder expands and contracts accordingly. Therefore, the distance between the frames 6 and 7 can be arbitrarily adjusted, and the filter 21 can be attached at a desired axial position regardless of the axial length of the rear lens 3, as shown in FIG. 1, for example. It is also possible to make the filter 21 contact the rear end of the rear lens 3. Also, by setting the maximum length of this holder at the maximum extension to the maximum axial length of the rear lens 3 to be used, the holder can be attached regardless of the axial length of the rear lens 3. You can Alternatively, a plurality of types of holders having different lengths at maximum extension may be prepared and used properly according to the axial length of the rear ball 3.

To mount the filter 21 on the holder, first, the two levers 19 are lifted upward, the rear frame 7 and the holding frame 8 are disengaged, and the holding frame 8 is opened. in this case,
Since both sides 8a of the holding frame 8 are made of the arch-shaped elastic material as described above, the elastic repulsive force allows the holding frame 8 to be opened only by releasing the engagement of the lever 19. In addition, the lower end of the holding frame 8
Since the pin 18 is attached to the rear frame 7 with play in both the front-rear direction and the up-down direction, the holding frame 8 can be opened widely.

Then, the filter 21 is inserted from above. In this case, since the holding frame 8 is open, the insertion can be easily performed, and when the plurality of filters 21 are inserted, the adjacent filters 21 are inserted.
Since the two do not rub against each other, the conventionally used mount becomes unnecessary, and the labor and cost for setting the filter on the mount can be saved, and the axial length of the holder can be shortened. Further, the guide pin 20 plays a role of accurately guiding the filter 21 when the filter 21 is inserted.

Next, the holding frame 8 is aligned with the rear frame 7, both levers 19 are lowered and engaged with both frames 7, 8, and the mounting of the filter 21 is completed. In this state, the filter 21
The holding frame 8 is firmly held by the elastic repulsive force of both side portions 8a.

(Effects of the Invention) As described in detail above, according to the present invention, the lens filter can be easily attached to a desired position regardless of the size of the taking lens.

[Brief description of drawings]

1 is a side view showing a state in which a holder according to the present invention is attached to a taking lens,
FIG. 2 is a side view of the holder, FIG. 3 is a plan view with a part of the holder omitted, FIG. 4 is a rear view with a part of the holder omitted, and FIG. It is the omitted front view. 1 ... Shooting lens, 2 ... Front lens, 3 ... Rear lens, 4 ... Lens board, 5 ... Mounting member, 6 ... Front holder, 7 ...
… Rear holder, 8 …… Holding holder, 21 …… Filter.

Claims (3)

[Scope of utility model registration request] 1. A lens filter mounting device in which a lens filter holder is provided on the rear side of the lens board of a photographic lens in which a front lens and a rear lens are mounted with a lens board sandwiched between them. A lens filter mounting device, which is configured to be extendable and contractible. 2. The lens filter mounting device according to claim 1, wherein a mounting member is fixed to the lens board, and the holder is mounted on the mounting member. 3. The lens filter mounting device according to claim 1, wherein the insertion portion of the lens filter is openable and closable.