JPH02204729A - Filter position detector for filter disk - Google Patents

Abstract

PURPOSE:To remove abrasion or the like due to sliding and to improve the durability and reliability of a filter disk by forming plural projected members corresponding to filters on the filter disk and outputting a selection signal from a switch member discriminating any one of the projected members. CONSTITUTION:The filters 71 to 74 are arranged on the filter disk 1, respective filters 71 to 74 can be selected by rotating the disk 1 like a turret and light passed through the selected filter is made incident upon a prism through a window 9 of a cover 8. At the time of selecting the filter 71, a projection 101 acts on a microswitch 63, and when the disk 1 is rotated furthermore by 1/4 rotation, the filter 74 is opposed to the window 9 and a projection 104 acts on the microswitches 62, 63. Thus, always highly reliable selection can be attained by a selection signal obtained by the combining selection of ON and OFF of the microswitches 61 to 63.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a position detection device for a color temperature conversion filter used as a color optical system of a television camera, etc., and particularly relates to a position detection device for a color temperature conversion filter used as a color optical system of a television camera, etc. The present invention relates to a filter position detection device for a filter disk that detects the position using a projection on the filter disk.

Furthermore, the present invention can also be applied to a position signal generating device for an extender of a zoom lens for a television camera.

(Prior Art) Conventionally, in this type of filter position detection device, as shown in FIG. By rotationally driving a gear shaft 4 which is interlocked with and rotates integrally with the wire brush 3 of the position detection section, a rotary switch made up of the wire brush 3 and the printed board 5 selects a color. It was designed to output a selection signal according to the filter.

(Problem to be solved by the invention) However, in the above conventional example, the wire brush 3
Since it is structured so that it slides on the patterned surface of the printed board 5, the surface of the patterned surface deforms due to wear etc. over time and has the drawback of easily causing poor conductivity or poor insulation. However, depending on the finish of the printed board 5, the lifespan is short, so that it is extremely unreliable as a unit to be incorporated into a television camera or the like.

(Means for Solving the Problems) Therefore, the present invention provides contacts such as switches, which are provided on the filter disk in order to open and close them, in place of the sliding parts of the wire brush 3 and the printed board 5 using rotary switches. A selection signal corresponding to the filter selected by the protruding member can be output.

This configuration eliminates wear caused by sliding and allows for highly reliable selection at all times.

(Example) Examples that specifically represent the present invention will be described below with reference to the drawings.

FIG. 1 is an external plan view of a 3P prism embodying the present invention;
FIG. 2 is a plan view showing a state in which the cover plate in FIG. 1 is removed. In the figure, 6I, 6□, and 63 are three small microswitches, each of which is a switch contact, and 7
is a filter visible through the window 9 formed in the cover plate 8;
10°, 10□, 103, and 104 are protrusions that open and close the microswitches 61, 6□, and 63, respectively.

The light that has passed through one of the filters 71, 7□, 73, and 74 selected on the filter disk 1 (shown in FIG. 3) further passes through the window 9 of the cover plate 8 and enters the prism. This cover plate 8 includes the micro switch 6,
・62 ・63 are held therein, and it also serves as a protection to prevent dust from entering the filter disk 1.

The light entering the prism is transmitted through each filter 71 and 7 by rotating the filter disk 1 in a turret style.
2, 73, and 74 can be selected. for example,
If filter 71 is selected, microswitch 6.1 has protrusion 10. When the filter disk 1 is rotated another 1/4 clockwise in the same way, the filter 74 faces the window 9, and the microswitch 62.
The protrusion 104 acts on 63. When the filter disc 1 is further rotated by 1/4, the filter 73 faces the window 9, the protrusion 103 acts on the microswitches 61 and 6263, and the filter disc 1 is rotated by 1/4
By rotation, the filter 7□ faces the window 9, and the projections 10□ act on the microswitches 6I and 63. This allows micro switch 6.・Filter disk selected based on the difference in on/off combination selection of 62 and 63 ・7.・72・7.・74 types can be identified.

Four recesses 11. are provided at the side edges of the filter disk 1 to precisely position the filter disks 71, 72, 73, and 74 so that they face the window 9.・112 ・11° 114 is formed so that it can engage with the roller 12 which is pressed by a leaf spring to produce a click feeling.

Further, in order to rotate the filter disk 1, a part of the outer periphery of the filter disk 1 is exposed to the outside as shown in FIG. The filter disk 1 can be easily rotated by turning its exposed outer periphery by hand.

The above is the protrusion 10.・102・103・104 Although the microswitch 6I・, 6263 is shown, instead of this microswitch 6゜62・63, the Hall element 13.・13□13 (not shown), and the protrusions 101102, 103, 104 can be replaced with magnets 14°142, 143, 144 (not shown) to detect the filter position in the same way.

In this case, since there is no contact, higher reliability and durability can be expected compared to projections.

(Effects of the Invention) As explained above, since the switch is opened and closed by the protruding member (switch reaction member) on the filter disk as in the present invention, it is much more durable than the conventional sliding method.・It improves reliability.

[Brief explanation of the drawing]

FIG. 1 is an external plan view of a 3P prism embodying the present invention;
FIG. 2 is a plan view showing the state in which the cover plate in FIG. 1 is removed, and FIG. 3 is a plan view showing the filter disk.
Figure 4 shows the second part of the outer circumference of the filter disc.
FIG. 5 is a partially enlarged view of the figure and a plan view showing a conventional example. In the figure, 1 is a filter disk, 6°62 ・6
3 is a micro switch, 71, 7273, and 74 are filters, 10. 10□103 ・104 is a protrusion,
13.・13□ ・133 (not shown) is a Hall element, 14.・142143 ・144 (not shown) is a magnet.

Claims (1)

[Claims] (1) In a filter position detecting device for a filter disc that selects one of a plurality of filters provided on a filter disc by rotating the filter disc, a filter position detection device for a filter disc that selects one of a plurality of filters provided on the filter disc by rotating the filter disc; A filter position detection device for a filter disk, comprising a plurality of protruding members and a plurality of switch members for selecting and identifying any of the protruding members.