JPS6114021Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a rotational force adjusting device for a drive spring cylinder in a focal plane shutter.

The drive spring cylinder has one end of the flexible shutter curtain member attached to it, and has an outer cylinder on the body circumferential side that has a shape that allows the shutter curtain member to be wound up, and is inserted through this outer cylinder and attached to the immovable part of the body. It consists of a bearing pivot member and a drive spring housed in the outer cylinder and having both free ends fixed to the outer cylinder and the pivot member, respectively, in order to give the shutter curtain member a running habit. When assembling, the outer cylinder is held stationary at a predetermined position, and only the pivot shaft member is rotated relative to the outer cylinder to store energy in the drive spring, thereby giving the outer cylinder a winding habit for curtain travel. It is configured to In such a driving spring cylinder, generally, in order to obtain an accurate shutter speed, it is possible to adjust the running speed of the shutter curtain member, that is, the rotational force of the outer cylinder for winding up the shutter curtain member. A rotational force adjusting device is provided which allows the pivot shaft to be locked at any rotational position. This rotational force adjustment device includes an adjustment gear fixed to one end of the pivot shaft, and a shaft member pivotally attached to the camera body near the gear, and a claw portion at the tip of the adjustment gear is fixed to the shaft member by a spring. The locking member is formed to elastically contact and mesh with the gear to prevent the adjustment gear from reversing, and is used to adjust the rotational force of the outer cylinder, that is, to store (relax) the drive spring.
Therefore, when the pivot member is rotated by a predetermined amount, a locking member is engaged with the adjustment gear, thereby locking the adjustment gear at an arbitrary rotational position.

However, in the above-mentioned well-known device, as a locking mechanism for locking the adjustment gear at an arbitrary position,
Recently, there has been a disadvantage that many members are required, such as a locking pawl, a spring for biasing the locking pawl, and a shaft member for pivotally connecting the locking pawl to a stationary part of the body. Therefore, it has been proposed that the locking pawl and the spring are integrated with an elastic material to reduce the number of parts and manufacturing cost.
That is, FIG. 1 shows such a conventional example, in which the pivot shafts B and C of the driving spring tubes for the leading and trailing curtains are inserted into the base plate A formed in the fixed part of the camera. Adjustment gears D and E are respectively fixed to the head. The adjustment gears D and E have claw portions J and E of a locking member T made of an elastic material fixed to the base plate A by screws, respectively.
They are in mesh with each other, and the adjusting gears D and E are configured to be locked at any rotational position by the pawls J and E.

Compared to the configuration of the above-mentioned known example, this conventional example has a locking pawl and a spring for biasing the locking pawl that are integrally formed into a single locking member. Although a spring is no longer necessary to bias the locking member, screws are still used to secure the locking member to the body, and in that respect,
It could not be said that the intended objectives of reducing the number of parts and assembly man-hours and costs were completely achieved.

This invention was made in view of the above points, and its purpose is to form a locking member of one piece to prevent the adjustment gear from reversing, and to attach the locking member to the body. There is no need for any special shaft members, reducing the number of parts and manufacturing/
It is an object of the present invention to provide a rotational force adjusting device for a drive spring cylinder that can significantly reduce the cost required for assembly.

Hereinafter, one embodiment of this invention will be described in detail with reference to the accompanying drawings. . In FIG. 2, 1 is an outer cylinder to which one end of a flexible shutter curtain member 2 as a front curtain is fixed by pasting, and 3 is an outer cylinder with one end fixed to a pivot 4 and the other end fixed to a fixing means (not shown). Therefore, the above outer cylinder 1
The drive spring 3 is formed into a shape that can be stored in the outer cylinder 1. Reference numeral 5 denotes a base plate extending from the immovable part of the camera body, and the base plate 5 has a shaft hole 6 into which the pivot shaft 4 can be inserted.
is drilled. An annular groove 7 is formed at the end of the pivot shaft 4, and an E-ring 8 is formed in the annular groove 7.
are formed so as to limit the amount of insertion of the pivot shaft 4 into the shaft hole 6 during assembly. Reference numeral 9 denotes a locking member formed by pressing a plate-shaped elastic material, and has a fitting hole 10 into which the pivot shaft 4 can be fitted, and claw portions 11a and 11b. This locking member 9 has a regulating hole for restricting the pivot shaft 4 from rotating around the pivot shaft 4 when it is fitted into the fitting hole 10, and for positioning the locking member 9 at a predetermined position. 12 is formed in this regulation hole, and in this regulation hole, a pivot shaft 14 (of a drive spring cylinder for winding up another shutter curtain member (for example, a rear curtain member), which passes through the base plate 5 in the same manner as the pivot shaft 4 described above, is formed. (shown only in Figure 3) can be fitted,
When the pivot shaft 14 is fitted, the locking member 9 is positioned at a predetermined position without rotating.

The drive spring tube for the rear curtain, which is not shown for convenience, has a structure similar to that of the drive spring tube for the front curtain described above, that is, it has an outer structure to which one end of the rear shutter curtain member is adhered and fixed. A pivot member 14 is supported between a cylinder, a base plate 5 inserted through the outer cylinder, and a body immovable part (not shown), and a pivot member 14 is housed in the outer cylinder and has both free ends pivoted to the outer cylinder. and a drive spring fixed to member 14. Reference numeral 13 denotes an adjustment gear that can be screwed onto the end of the pivot 4, and when screwed onto the pivot 4, the locking member 9 can be inserted between it and the base plate 5, as shown in FIG. It is possible to form a gap of A gear 15 (shown only in FIG. 3) having the same shape as the adjustment gear 13 is an adjustment gear that can be screwed onto the rear curtain pivot 14.

In the above configuration, in order to assemble the drive spring cylinder, the pivot shaft 4 to which one end of the drive spring 3 is fixed is inserted into the outer cylinder 1, and the other end of the drive spring 3 is attached to the outer cylinder 1 by a fixing means (not shown). stick. Next, the E-ring 8 is fitted into the annular groove 7 formed at one end of the pivot 4, and the one end of the pivot is inserted into the shaft hole 6 of the base plate 5. Then, the locking member 9 is fitted into the pivot shaft 4 penetrating through the base plate 5 through the fitting hole 10, and the adjustment gear 1 is attached to the head of the locking member 9.
Screw on 3. In this state, the claw portion 11a of the locking member 9 is engaged with the adjustment gear 13, as shown in FIG. 3, and the pivot shaft 4 is engaged with the E-ring 8 and the adjustment gear 12, as shown in FIG. Therefore, movement in the axial direction with respect to the base plate 5 is restricted, so that the locking member 9 is held between the base plate 5 and the adjustment gear 12. On the other hand, in the locking member 9, a pivot shaft 14 of a trailing blade drive spring tube formed similarly to the drive spring tube described above passes through the base plate 5 and is inserted into the regulation hole 12, whereby the locking member 9 Movement in the rotational direction about the pivot shaft 4 is restricted. moreover,
An adjustment gear 15 is screwed onto the pivot shaft 14 of the trailing blade drive spring cylinder. In this state, as shown in FIG. 3, the other claw portion 11b of the locking member is engaged with the adjustment gear 15 for the rear curtain. In order to adjust the traveling speed of the shutter curtain member in the drive spring tube assembled as described above, an operating member (not shown) is inserted into the operating holes 13a, 15a provided in the adjusting gears 12, 15, and the adjusting gear is rotated. All you have to do is rotate 12 and 15.
For example, in order to increase the running speed of the front shutter curtain member, the adjustment gear 13 may be rotated to store energy in the drive spring provided between the pivot shaft 4 and the outer cylinder 1. Incidentally, when rotating the gears 13, 15, there is a gap between the gears 13, 15 and the base plate 5.
As shown in FIG. 4, the screwing amount of the gear is regulated so that a gap is provided for the interposition of the locking member 9, so that the gear does not rotate alone and the pivot shafts 4, 14 rotates as a unit. When the power to rotate the adjustment gear is removed after the drive spring has been charged, the claw portion 11a of the locking member 9 is elastically engaged with the gear, so there is no possibility that the pivot shaft 4 will reverse due to the spring force. do not have.

As shown in the above embodiments, the locking member 9 includes
If a configuration is adopted in which the pawl portion 11b that elastically engages with the adjustment gear fixed to the pivot of another drive spring cylinder (in the above example, the drive spring cylinder for the trailing blade) is integrally formed, for each adjustment gear, Since there is no need to separately attach a locking member to prevent the adjustment gear from reversing, the working time and number of parts can be reduced.

In the above embodiment, as a means for positioning and fixing the locking member 9 to the base plate 5, the locking member 9 is provided with a fitting hole 10 into which the pivot of the drive spring cylinder fits and a regulating hole 12. , a configuration was adopted in which the locking member 9 was positioned at a predetermined position on the base plate 5 by inserting a pivot through these two holes,
Instead of these two holes, there is a notch 1 that can be engaged with each pivot in the locking member 9, as shown in FIG.
0', 12' may be formed, and the locking member 9' may be located between both the pivot shafts.Alternatively, it is also possible to form only one of the two holes with a notch. be.

In this way, if at least one of the parts that fit with the pivot is formed with a notch, the fitting position of the pivot with respect to the notch becomes free in the direction of the cut of the notch. Compared to a configuration in which the position is regulated using a hole, the required machining precision of the locking member does not have to be so high, so manufacturing and processing costs can be reduced. .

In addition, as another embodiment of this invention, the locking member 9
After the locking member 9 is fitted into the pivot shaft 4, the locking member 9 or It may be formed on either one of the base plates 5 so that when the locking member 9 attempts to rotate, it comes into contact with the engaging portion and restricts the rotational movement.

If such a configuration is adopted as the regulating means, it is only necessary to fit the locking member 9 to one of the pivots during assembly, so the positioning work for fitting the locking member 9 to the pivot is as simple as As shown in each of the above-mentioned embodiments, compared to the structure in which the locking member is fitted to both the leading and trailing curtain pivots, only one positioning operation is required, so the assembly operation can be simplified.

In addition, by adopting a structure in which the locking member only fits into one of the two pivots, each pivot can be disassembled and assembled individually, making repairs and parts replacements quicker. It becomes possible to do so.

As described above, in this device for adjusting the winding speed of the shutter curtain member of the drive spring cylinder, the locking mechanism for locking the adjustment gear at an arbitrary rotational position is made of a plate-shaped elastic material. The locking pawl portion and the urging means for bringing the locking pawl into elastic contact with the adjustment gear are integrally formed, and the means for fixing the locking member to the base plate includes a pivot shaft of the drive spring cylinder. Compared to the conventional example, we adopted a structure in which the body is also used as a member for attaching it to the body.
Special fixing means such as screws for attaching the locking member to the base plate on the body side are completely unnecessary, and the number of parts can be reduced.

Furthermore, according to this invention, the assembly work for attaching the locking member to the base plate is completed in synchronization with the work for assembling the drive spring tube into the camera body, so that No special work is required at all, and the number of assembly steps and time can be significantly reduced, leading to cost reductions.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing only the main parts of a conventional example of the present invention, Fig. 2 is an exploded perspective view showing only the main parts of an embodiment of the invention, and Figs. 3 and 4 are the same embodiments. Fig. 3 is a bottom view, Fig. 4 is a sectional view of the main part, and Fig. 5 is an enlarged perspective view showing only the main part of another embodiment of the present invention. . 1... Outer tube, 2... Shutter curtain member, 3...
Drive spring, 4, 14... Pivot, 5... Base plate, 8... E ring, 9... Locking member, 11b,
11b...Claw portion, 13, 15...Adjustment gear.

Claims (1)

[Claims for Utility Model Registration] 1. Shutter front curtains and rear shutter curtains capable of forming exposure slits when the vehicle is running are adhered and fixed, and when the vehicle rotates in one direction, a drive spring is loaded according to the amount of rotation, and the shutter is first and second drive spring tubes configured to generate rotational force for winding up the leading curtain and the trailing curtain, respectively; a base plate having openings at different positions; and a pivot shaft of each of the first and second drive spring tubes passing through the opening and being fixed to one end thereof, and being integrally connected to the respective pivot shafts; first and second adjustment gears that rotate, and two fitting portions into which both of the pivot shafts passing through the openings can be fitted, and between the first and second adjustment gears and the base plate. The shafts are clamped by the shafts to restrict movement in the extension direction of the shaft, and the shafts are fitted together to prevent movement in the rotational direction about the shaft, and the shafts are individually engaged with the adjustment gears. A plate-shaped locking member made of an elastic material and having two pawls capable of locking the adjustment gear at any rotational position. Rotational force adjustment device. 2 The two fitting parts in the locking member are the first and second fitting parts.
2. The rotational force adjusting device according to claim 1, wherein the pivot shafts of the drive spring cylinders are each formed with a fitting hole that can be fitted with substantially no gap. 3. The rotational force adjusting device according to claim 1, wherein the two fitting portions of the locking member are substantially U-shaped notches formed at both ends of the locking member.