JPS61129501A - Measuring instrument for movement extent of camera lens - Google Patents

Abstract

PURPOSE:To measure the accurate movement extent of a camera lens even if the lens has a slight error in fitting position, etc., by using a linear ball bearing as a member for holding a contact rod which contacts the camera lens. CONSTITUTION:The linear ball bearing 8 is fitted in the tip part in a holder 4A. The bearing 8 has balls on its internal wall surface to allow movement with extremely small friction. The contact rod 3A penetrates the bearing 8 and is movable in the optical-axis direction of the lens. Then, a contactless displacement gauge 6 and a coil spring 7 are arranged and the flange at the rear end part of the contact rod 3A is pressed by the coil spring 7, so that the front end surface of the contact rod 3A abuts on the lens 1. The contact rod 3A moves in the optical-axis direction of the lens 1 with extremely small friction, so the front end surface of the contact rod 3A moves integrally in the optical-axis direction while abutting on the lens 1 all the time regardless of irregularity in the fitting position of the lens 1. Therefore, the contactless displacement gauge 6 detects the accurate movement extent of the lens 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention provides an apparatus for measuring the amount of movement of a camera lens, and furthermore, a device for measuring the amount of movement of a camera lens. The present invention relates to an apparatus for measuring the amount of movement of a camera lens.

(Prior art) In the camera assembly process at a factory, for example, mx of an autofocus camera (hereinafter referred to as AF camera)
When the process is completed, various tests will naturally be carried out. One of the inspections is a step of inspecting that the amount of movement of the AP left camera lens must be within a certain value depending on the distance from the closest distance to infinity.

Conventionally, five means as shown in FIG. 3 have been used as inspection means for measuring the amount of movement of the AP left camera lens as described above. That is, the lens 1, whose lens surface faces the subject, is fixed to the inner surface of the tip of the lens frame 2, which is movable in the optical axis direction of an AP left camera body (not shown). In front of this lens 1 is the camera lens displacement Dx: 9. A setting device 2o is provided oppositely. This outfit! Reference numeral 20 denotes a non-contact displacement meter 6, which is a squirting current type gap sensor, fixed to the center of the bottom of the inner wall of the cylindrical holder 4, and a sensor part 6 of this displacement meter 6.
The contact rod 3 is slidably disposed in a holder 4 at 5K opposite to the contact rod 3a. This contact rod 3 is
The sliding part 3a at the rear end has a short cylindrical shape that is slightly thinner than the inner diameter of the holder 4, and a thin cylindrical contact extends from the center of the sliding part 3a toward the front, that is, toward the side of the lens 1. The portion 3b extends out.

The center axis of the contact rod 3 is arranged at 5 so that it coincides with the optical axis of the lens 10, and the front end surface of the contact portion 3b is arranged at 5 so that it comes into contact with the center of the lens 1. . This contact rod 3 has a guide hole 5c parallel to the central axis of the contact rod 3 at a symmetrical position near the outer periphery of the sliding portion 3a.
, 3d are provided, and this guide hole 3c, 3dV
Guide rods 5a and 5b are inserted into the bottom of the inner wall of the holder. Therefore, these guide rods 5a, 5b
Therefore, the contact rod 3 is configured to move while sliding in the optical axis direction. Moreover, these guide rods 5a and 5b
A stopper is provided at each tip, and
An extensible coil spring 7 is disposed between the bottom of the inner wall of the holder 4 and the rear end surface of the contact rod 3, and is designed to push the contact rod 3 forward.

The amount of movement of the camera lens is measured using the camera lens movement amount measuring device 20 configured as shown in FIG.
is the value of the non-contact displacement meter 6 when the AP left camera body is fixed, the contact part 3b of the contact rod 3 is pressed against the front center of the lens 1, and the lens 1 is moved from close range to infinity. All you have to do is read.

However, when assembling the AP left camera lens 1, as a matter of course, errors between the lens 1 and the lens frame 2, or errors in the feeding mechanism of the lens frame 2, etc., accumulate, and the amount of movement is measured. When the assembled AP left camera of the device 20 is set, the contact portion 3b of the contact rod 3 and the lens 1 do not necessarily come into uniform contact, and some unevenness may occur. If this unevenness is large, the guide holes 5c and 3d of the contact rod 3 and the guide rod 5a
, 5b may become abnormally large, and in this case, the lens 1 and the contact rod 3 may no longer come into contact with each other. Therefore, there are five drawbacks in that the amount of movement of the lens 1 may not be accurately detected by the non-contact displacement meter 6VC.

(Purpose) The purpose of the present invention is to accurately measure the amount of lens movement even if there is some error (unevenness) in the mounting position of the lens of the assembled camera or the mounting position of the lens frame extension mechanism. K provides a device for measuring the amount of movement of a camera lens with a 51C design.

(Summary) In order to achieve the above object, the present invention uses a linear ball bearing, which has extremely low friction when the contact rod is inserted, as a member for holding the contact rod that contacts the camera lens. Even if there is unevenness, the contact rod is shaped so that it can follow this unevenness.

(Examples) The present invention will be described below based on illustrated examples. 1st
The figure is a cross-sectional view of a camera lens movement amount measuring device showing a first embodiment of the present invention. Note that in both this embodiment and the second embodiment described below, the existing Kit! Components that are the same as those described above will simply be given the same reference numerals to avoid redundant explanation.

As shown in FIG. 1, a well-known linear ball bearing 8 is fitted and fixed at the tip end inside the holder 4A.

This linear ball bearing has a ball bearing disposed on its inner wall, and a round rod inserted in the axial direction so as to come into contact with this ball bearing can be moved with very little friction. In the present invention, this linear ball bearing 8VC contact rod 3A is inserted, and these three contact rods are movable in the optical axis direction of the lens. Similarly to the conventional example described above (see FIG. 3), a non-contact displacement meter 6 and a coil spring 7 are provided, and the coil spring 7 presses the flange at the rear end of the contact rod 3A. The front end surfaces of these three contact rods are brought into contact with the lens IVc.

In this way, the contact rod 3A inserted into the linear ball bearing 8 can move in the direction of the optical axis of the lens with very little frictional force, so it can be easily moved against unevenness in the mounting position of the lens 1. The three contact rods can move together in the optical axis direction with their front end surfaces always in contact with the lens 1. Therefore, the non-contact displacement meter 6 can accurately detect the amount of movement of the lens 1.

Next, a second embodiment of the present invention will be described based on FIG. As shown in FIG. 2, a linear ball bearing 8 is fitted and fixed in the upper front end of the holder 4B, and a slightly longer contact rod 3B is inserted through the linear ball bearing 8. A 7-lunge is provided near the center of the contact rod 3B, and a coil spring 7 is stretched between the 7-lunge and a stepped portion provided on the inner wall slightly to the left of the center of the holder 4B. , suppresses the contact rod 3B to the right. The upper end of the measured value enlargement lever 9 is connected to the rear end of the contact rod 3B. This lever 9 uses a portion near its upper end as a fulcrum, and the holder 48
It is rotatably supported by a bottle 11 fixed to the bottle 11, and rotates around the bottle 11. and,
A guide elongated hole 9a is provided at the lower end of this lever 9.

A non-contact displacement gauge 6 is disposed on the lower front wall of the holder 4B, and a sensor part 6a of the displacement gauge 6 is arranged so as to face the 7 langes 10a at the front end of the driven rod 10. ing. This driven rod 10 is a linear ball bearing 8AK that is fitted and fixed in the center of the lower part of the holder 4B.
5 so that it can move freely parallel to the contact rod 38. A pin 10b is molded into the rear end of the driven rod 10, and the pin 10b is shaped like a 5 to fit into the elongated guide hole 9a VC of the lever 9.

In this way, even if the lever 9 is used to measure the amount of movement of the contact rod 3B by expanding it depending on the lever ratio, the frictional force of the linear ball bearing 8.8A is very small, so the measured value It has no effect on

Furthermore, since the amount of movement of the lens 1 can be enlarged and measured as described above, measurement accuracy can be improved.

In addition, in the first and second embodiments, the case where the contact rod was brought into contact with the lens was shown, but it goes without saying that the measurement may be made by bringing the contact rod into contact with the lens frame. .

(Effect) According to the present invention, the frictional force is extremely reduced by forcing the contact rod that contacts the lens or lens frame through a linear ball bearing, so even if the lens is installed unevenly, etc. However, the contact rod can follow this unevenness and accurately detect the amount of movement of the lens.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a camera lens movement measuring device according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of a camera lens movement measuring device according to a second embodiment of the present invention. FIG. 3 is a sectional view of a conventional camera lens movement measuring device. 1...φψ...Φ・Lens 2・Life...Bone...-Lens frame 5.5A, 5B...Contact rod 6...Non-contact displacement meter 7... ......Coil spring 8.8A...Linear ball bearing procedure amendment (self-motivated) June 5, 1985 1. Indication of incident 1985 Patent Application No. 252275 2. Invention Name of camera lens movement measurement device 3,
Relationship with the case of the person making the amendment Patent applicant location 2-43-2 Hatagaya, Shibuya-ku, Tokyo Name (037) Olympus Optical Industry Co., Ltd. 4;
I will correct it to "thick wall". (2) Delete "distance to infinity" written in line 8 of page 4 of the same document, and change it to "from the lens position where the object point forms its image on the film surface to the lens position where the infinite object point forms its image on the film surface. ”
Assign .

Claims (2)

[Claims] (1) A contact rod that contacts the lens or lens frame and moves together with it; A displacement meter that measures the amount of movement of this contact rod; and a displacement meter that moves the contact rod in the optical axis direction of the lens. A camera lens movement measuring device characterized by comprising: a linear pole bearing that slidably holds the contact rod; (2) The camera lens movement measuring device according to claim 1, wherein the camera lens is an autofocus camera lens.