JPH0448568Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a remote-controlled iris shutter used for stage floodlights and the like.

[Background technology] The conventional remote-controlled iris shutter
As shown in the figure, it is provided between the light source 12 and reflector 13 at the rear of the projector body 11 and the objective lens 14 at the front, and narrows down the luminous flux of the projector by opening and closing the iris blades 4. However, in the transmission mechanism A for driving the iris shutter S by the motor 1, an arc-shaped large gear that meshes with a small gear 6 attached to the motor shaft 5 is connected to the guide body 1.
The rotation of the large gear 7 is transmitted via the U-shaped engagement plate 18 and the engagement rod 19 to the iris rotary plate 3 that opens and closes the iris blade 4. Ta.

However, in the above transmission mechanism, the center of the iris body 2, which serves as a guide for the iris rotating plate 3, and the large gear 7
The center of the guide body 17, which serves as a guide for the motor 1, there is a delay in the opening/closing operation of the iris shutter during forward and reverse rotation, and the aperture area cannot be precisely controlled.

[Purpose of the invention] The present invention was devised in view of the above points, and its purpose is to eliminate the need for play in the transmission mechanism between the motor and the iris shutter, and to provide a highly accurate response. To provide a remote control type iris shutter which can perform opening/closing control with good performance.

[Disclosure of the invention] Accordingly, in the present invention, the transmission mechanism A is transmitted by the motor 1.
In the iris shutter, the opening area of the iris blades 4 is adjusted by the rotation angle of the ring-shaped iris rotary plate 3 which is rotated using the inner circumferential surface 2a of the iris body 2 as a guide. A small gear 6 attached to the shaft 5, and an arc-shaped large gear 7 that meshes with the small gear 6 and slides using the outer peripheral surface 2b of the cylindrical iris body 2 as a guide.
The transmission mechanism A is formed by the large gear 7 and the connecting plate 8 that bridges the end faces of the iris rotating plate 3 and connects the large gear 7 and the iris rotating plate 3 with the iris main body 2 in between. The large gear that transmits the rotation of the motor to the iris rotating plate and the iris rotating plate are guided by the outer and inner circumferential surfaces of the cylindrical iris body, and the center of rotation of both is completely aligned. In order to match this, there is no need to create any play between the two, so there is no delay in response to forward and reverse rotation during remote control, and the opening area can be precisely controlled. .

[Example] Fig. 1 shows an example in which the iris shutter of the present invention is implemented in a projector, in which a light source 12 and a reflector 13 are arranged in the rear part of the projector main body 11, and an objective is installed in the front part. A lens 14 is disposed, and an adjustment screw 1 is provided for adjusting the focal position of the objective lens 14.
5 is provided on the top surface of the projector main body 11, and the iris shutter S is provided at a position that partitions the interior of the projector main body 11 into front and back parts, and the iris shutter S is provided at a position that partitions the inside of the projector main body 11 into front and rear parts. via a transmission mechanism A.

2 and 3 a and b show the structure of the iris shutter S and the transmission mechanism A, in which the iris main body 2 is formed in a cylindrical shape, and its inner peripheral surface 2a
A ring-shaped iris rotating plate 3 that rotates using the iris rotating plate 3 as a guide is rotated by the motor 1 via the transmission mechanism A, and the opening area of the iris blade 4 is adjusted according to the rotation angle of the iris rotating plate 3. The transmission mechanism A includes a small gear 6 attached to the motor shaft 5, and an arc-shaped large gear 7 that meshes with the small gear 6 and slides using the outer peripheral surface 2b of the cylindrical iris body 2 as a guide. The large gear 7 and the connecting plate 8 bridge the end faces of the iris rotary plate 3.

In FIG. 2, when the motor 1 rotates by a predetermined angle according to the control pulse signal, the large gear 7 is rotated through the small gear 6 while slidingly contacting the outer peripheral surface of the iris body 2, and at the same time, the large gear 7 is rotated through the small gear 6 through the connecting plate 8. The iris rotating plate 3 is integrated with the large gear 7.
rotates while slidingly contacting the inner peripheral surface of the iris main body 2 to open and close the iris blades 4. 9 in the figure is a limit switch for detecting the rotation limit position of the large gear 7. Note that the connecting plate 8 may be integrally provided to protrude from the iris rotating plate 3.

[Effects of the invention] As described above, the present invention has a large arc-shaped gear that meshes with a small gear attached to the motor shaft and slides using the outer circumferential surface of the cylindrical iris body as a guide, and the inner circumference of the iris body. The end faces of the ring-shaped iris rotating plate, which rotates using the surface as a guide, are bridged together, and the large gear and the iris rotating plate are connected by a connecting plate with the iris main body in between. The large gear and the iris rotating plate, which are in a fixed relationship, are rotated using the iris body as a common guide, so that the rotation centers of the large gear and the iris rotating plate are completely aligned, and there is no space between them as in the past. There is no need to provide play, so there is no delay in opening/closing operations relative to forward and reverse rotation during remote control, and the opening area has the advantage of being able to be accurately controlled.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing an embodiment of the present invention, Fig. 2 is a front view of the main parts of the same, Fig. 3 a is a perspective view of the main parts of the same, and b is an exploded perspective view of the main parts of the same. Figure 4a
1 is a longitudinal sectional view of the conventional example, and b is an exploded perspective view of the same essential parts. S...Iris shutter, A...Transmission mechanism,
1...Motor, 2...Iris body, 2a...Inner peripheral surface, 2b...Outer peripheral surface, 3...Iris rotating plate,
4...Iris blade, 5...Motor shaft, 6...Small gear, 7...Large gear, 8...Connection plate, 9...Limit switch.

Claims (1)

[Scope of utility model registration request] It is rotated by a motor via a transmission mechanism,
In an iris shutter, the opening area of the iris blade is adjusted by the rotation angle of a ring-shaped iris rotating plate that rotates using the inner peripheral surface of the iris body as a guide. An arc-shaped large gear that meshes with the gear and slides using the outer peripheral surface of a cylindrical iris body as a guide, and an iris that bridges the end faces of the large gear and the iris rotating plate to connect the large gear and the iris rotating plate. A remote-controlled iris shutter in which the above-mentioned transmission mechanism is formed by a connecting plate connected with the main body sandwiched therebetween.