JPH0447873Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to an encoder for converting the set position of an actuating member in an optical instrument into an electrical signal.

(Background of the invention) In recent years, the computerization of photographic equipment has progressed significantly, and various types of information are processed in the form of electrical signals in order to automate automatic exposure, automatic focusing, etc. For example, in an interchangeable lens for a single-lens reflex camera, information on a focal length set in accordance with the operation of a zoom operation ring is transmitted as a digital electrical signal to a microcomputer in the camera body.

In this way, in order to convert the set position of an operating member such as a zoom operation ring into an electrical signal, a brush is slid over a pattern consisting of a conductive part and an insulating part, and a signal code corresponding to the brush position is generated. A so-called encoder is used to output the signal.

However, looking at the structure of encoders in conventional photographic equipment, they generally do not have a special mechanism for adjusting the relative position between the encoder pattern and the brush.

Therefore, there was a drawback that relative positional deviation between the encoder pattern and the brush easily occurred, and the accuracy of the encoder was low.

In addition, in order to visually adjust the brush position, the encoder section needs to be visible from the outside of the device, which has the disadvantage of complicating the structure.

(Objective of the invention) An object of the present invention is to solve these drawbacks and to easily and accurately align the signal pattern and the signal detection member.

(Summary of the invention) This invention makes it easy to visually see the signal pattern from the outside by forming the member that holds the signal detection member from a transparent synthetic resin material, and the member that holds the signal detection member is positioned on the substrate on which the signal pattern is formed. The technical point is that alignment marks are provided, and a positioning index is provided on either the signal detection member or the holding member, thereby realizing ease and high accuracy of the alignment work.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 to 4 show an embodiment in which the present invention is applied to a lens information setting device for a zoom lens for an interchangeable camera.

First, the overall structure will be explained with reference to FIG. The mount lens barrel 13 is attached to a camera body (not shown) with a bayonet 13a. The fixed lens barrel 11 fixed to the mount lens barrel 13 fixes and holds the lens group G2 on its inner diameter. When the zoom operation ring 19 is rotated, the zoom cam cylinder 23 connected by the groove 19a and the pin 29 also rotates, so the cam pin 2 implanted in the zoom movable cylinder 25 that slides on the inner diameter of the fixed cylinder 11 rotates.
7 and a cam groove 23 formed in the zoom cam barrel 23
a and the linear groove 11a formed in the fixed barrel 11, the zoom movable barrel 25 and the lens group G1 move in the optical axis direction, and the focal length changes. A rubber ring 15 having a non-slip knurl is wound around the outer periphery of the zoom operation ring 19.

An encoder 2, which will be described later, is installed on the outer periphery of the fixed cylinder 11.
A circuit board 1 comprising a one-chip microcomputer (hereinafter referred to as microcomputer) MC1, etc. is fixed by screws 33 and 35 (see FIG. 1). A part of the circuit board 1 extends to the inner diameter of the mount lens barrel 13, and the mount contact pin 3
1 _C1 to 31 _C4 are connected to the communication input/output ports C1 to C4 of the microcomputer MC1 (see FIG. 3). The mount contact pins 31 _C1 to 31 _C4 are connected to camera body contacts (not shown) by contact holding members 32.

The encoder brush 3 is attached to the opening 19b of the zoom operation ring 19 on the inner diameter side with a screw 37 (see Fig. 1).
A brush holding member 5 fixedly held by is inserted and fixed from the outer diameter side. A gap is provided between the brush holding member 5 and the wall 19b' forming the opening 19b, and the position of the brush 3 with respect to the zoom operation ring 19 is adjusted by moving the brush holding member 5 in the circumferential direction. After the adjustment is completed, adhesive tape 17 is applied to the outer periphery of the brush holding member 5 and the zoom operation ring 19 to fix the brush holding member 5 to the zoom operation ring 19.
If the rubber ring 15 is attached to the outer periphery after fixing, the adhesive tape 17 and the brush holding member 5 will not be exposed to the outside of the lens.

FIG. 1 shows the brush holding member 5, from the right side in FIG.
FIG. 3 is a cross-sectional view of the brush 3, the circuit board 1, and the like. FIG. 2 is a perspective view of the brush holding member 5 and the brush 3.

FIG. 3 is a developed view of the circuit board 1 where the encoder section 2 and the microcomputer MC1 are arranged. The encoder section 2 has conductor patterns 2a to 2c and 2g as encoder patterns on an insulating substrate, and each conductor pattern is connected to the microcomputer MC1.
are electrically connected to the input ports I ₁ ~ _{I 3} and the ground pin GND. The encoder brush 3, which moves in conjunction with the rotation of the zoom operation ring 19, slides on the surface of the encoder section 2 in the direction of arrow B, and the brush tips 3g, 3a, 3b, and 3c have conductor patterns 2g, 2a, 2b, and 2c, respectively. configured to come into contact with. Since the conductor pattern 2g is connected to pin GND which is the ground level (potential 0) of the microcomputer MC1, the conductor pattern in contact with the brush 3 and the microcomputer MC depend on the position of the brush 3.
The input port No. 1 has a potential of 0 volts (Low), and the conductor patterns and input ports that are not in contact have a potential of High potential. Therefore, a signal code corresponding to the position of the brush 3 is input to the input ports _I1 to _I3 of the microcomputer MC1. Furthermore, the microcomputer MC1 reads lens information (for example, focal length setting) corresponding to the input code from the internal memory in the microcomputer MC1, and outputs it as a digital signal from the data output port _C4 according to a predetermined format. This data will be sent to the circuit within the camera body via the mount contact _31C4 .

The brush 3 moves in conjunction with the rotation of the zoom operation ring 19 from the position of the brush 3 indicated by a solid line in FIG. 1 to the position of the brush 3' indicated by a broken line. Brush 3, 3' and encoder 2 at their respective positions
The contact positions with P _T and P _W are shown. Here, P _T represents a contact point of the zoom operation ring 19 at the telephoto side rotation restriction position, and P _W represents a contact point at the wide side rotation restriction position. Also in Figure 3, the position
P _T and P _W are indicated by dashed lines. In this embodiment, by rotating the zoom operation ring 19, the lens group G1 is slid in the optical axis direction to perform zooming, and in conjunction with this, the brush 3 is slid between P _T and P _W. Setting focal length information corresponding to the rotational position of the zoom operation ring 19 is transmitted to the camera body via the microcomputer MC1.

Now, in the encoder device having the above structure, in order to adjust the relative position between the brush 3 and the encoder 2, the conductor patterns 2a to 2c of the brush 3 and the encoder 2 need to be visible from the outside of the lens barrel. To this end, in this embodiment, the brush holding member 5 is made of a transparent synthetic resin material such as methacrylic resin, so that even if the brush tips 3a to 3c are inside the brush holding member 5, they can be easily seen. ing. If the brush holding member 5 is opaque, a tool hole for viewing the brush tips 3a to 3c may be provided, or the brush shape may be changed so that the opening 19b of the zoom operation ring 19 and the brush holding member 5 are opaque.
It is necessary to make it visible through the gap between the material and the material, which causes problems such as reduced strength, poor workability, and a complicated structure.

Further, the brush holding member 5 is provided with index grooves 5a and 5b (FIGS. 1 and 2) each having a V-shaped cross section, and the positions of the index grooves 5a and 5b are as shown in FIG. Brush 3 on the extension of the line connecting
The point of contact with the encoder 2 is located here. Further, on the surface of the encoder 2, reference position display marks 2g', 2d, 2g'', 2c' are placed on the conductor pattern 2 at the positions of the encoder reference positions P _T and P _W.
g, 2c, or separately from the conductive pattern. Mark 2g′, 2g″, 2
c' has a triangular shape, and its apex corresponds to the encoder reference position. The mark 2d is a rectangle with a constant width, and the width corresponds to the adjustment variation tolerance of the brush position.

To adjust the brush position, the zoom operation ring 19 is fixed at the rotation limit position at the tele end or wide end, and then the index grooves 5a, 5b of the brush holding member 5 and the reference position marks 2g', 2d, or 2 of the encoder 2 are adjusted.
g'', 2c', adjust the position of the brush holding member 5 so that the marks 2g, 2d or 2g'', 2c' are on the extension line of the index grooves 5a and 5b, and then move the brush holding member 5 to the operating ring 19. Fix it with adhesive tape 17. Generally, when looking at the brush tip from directly above,
It is difficult to tell where the contact points with the encoder are, and adjustment errors are likely to occur, but the index grooves 5a and 5b
That won't happen if you use . Furthermore, since two indicators, the indicator grooves 5a and 5b, are used, parallax does not occur, and adjustment errors are small.

In this embodiment, the brush holding member 5 has indicators 5a, 5.
b is provided, but this may be omitted and the reference position mark may be provided only on the encoder 2. Even if this is done, it does not depart from the scope of the present invention.

FIG. 5 shows an index groove 5 provided in the brush holding member 5.
This is a modified example in which adjustment indicators are provided on the brush 103 instead of a and 5b. The brush tip is encoder 2
An external step 103a is formed at the contact position with the conductor pattern (more specifically, the conductor pattern). In this case, the step is 10
3a and a reference position mark 2g' provided on the encoder conductor pattern 2g, relative positioning of the brush 103 and the encoder 2 can be performed. Figure 6 shows brush 1
03 is shown.

Note that the conductor patterns 2t and 2w in FIG. 3 are conductor patterns formed with letters representing the telephoto end and wide end of the encoder, respectively. These are for identification during manufacturing or assembly, and have the advantage that the focal length position can be immediately determined visually.

Further, in the above-described embodiment, the fixed lens barrel 11 is provided with a conductor pattern, and the zoom operation ring 19 is provided with brushes 3, 103 to detect the conductor pattern electrically, but the fixed lens barrel 11 has a reflective pattern that reflects light. is provided, the light emitting element and the light receiving element are supported by the holding member on the zoom operation ring 19, and the light emitted from the light emitting element is reflected by the reflection pattern.
The rotating position of the zoom operation ring may be detected photoelectrically by receiving light with a light receiving element. In this case, the holding member is made of a transparent material, and a position mark is provided on the holding member or the light emitting element or the light receiving element to indicate the position of light irradiation onto the reflective pattern, and a position mark is also provided on the reflective pattern, and both position marks are provided. The relative position between the holding member and the reflective pattern may be adjusted by means of the above.

Furthermore, although the above embodiment shows the case of an interchangeable lens for a camera, the application of the present invention is not limited to photographic lenses. Needless to say, this is possible for all necessary equipment. Furthermore, the encoder is not limited to digital signals, but can also be applied to analog signals that utilize changes in resistance values, etc.

(Effects of the invention) As described above, according to the invention, the contact portion between the signal detection member and the signal pattern can be easily seen from outside the lens, and the holding member and signal detection member can be easily seen by simply aligning the positioning marks and indexes. Since either one and the signal pattern can be in a predetermined positional relationship, position adjustment work can be easily and accurately performed.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the present invention, in which FIG. 1 is a partial sectional view, FIG. 2 is a perspective view of parts, and FIG.
The figure is a developed view of the encoder part, FIG. 4 is a cross-sectional view of the entire embodiment, and FIGS. 5 and 6 show other embodiments.
FIG. 5A is a plan view of the component, FIG. 5B is a side view thereof, and FIG. 6 is a perspective view of the component. Explanation of symbols of main parts, 2a, 2b, 2c, 2
g... Signal pattern, 3,103... Signal detection member, 5... Holding member, 19... Actuation member.

Claims (1)

[Claims for Utility Model Registration] (1) A substrate having a signal pattern; a signal detection member that moves on the signal pattern of the substrate to detect a signal; and a signal detection member disposed above the substrate and facing the substrate. a holding member that holds the signal detection member on a surface that is movable along the signal pattern in conjunction with an external operation; In the signal setting device for an optical device that obtains an electric signal according to the movement position of the holding member that moves, the holding member is formed of a transparent material that allows the signal detection member and the signal pattern to be visually seen, and In order to perform an adjustment operation to bring one of the holding member and the signal detection member into a predetermined positional relationship with the signal pattern, an index is formed on one of the holding members and the signal detection member, and an index is formed on the substrate near the signal pattern. A signal setting device for an optical device, wherein an alignment mark is formed for aligning the index, and the alignment mark has a width that allows adjustment variations in the adjustment operation. (2) The signal setting device for an optical device according to claim 1, wherein the holding member has adjustment means that allows adjustment of the mounting position of the holding member with respect to the optical device.