JP2018194755A - Lens holding barrel - Google Patents

Abstract

To provide a lens holding barrel capable of suppressing ultraviolet curable adhesive from coming around a lens holding frame for bonding and fixing a lens and a shadow of the lens to prevent uncured adhesive.SOLUTION: A lens holding barrel is configured such that a lens is inserted into a lens holding frame and the lens is adhered to the lens holding frame, and includes a first lens shoulder unit for configuring the lens at a prescribed position in the lens holding frame and a recess for storing adhesive in an angle phase unit different from the lens shoulder unit. In an inner diameter side of the recess of the lens holding frame, a second shoulder unit in contact with the lens is provided.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a lens holding frame that can be mounted on an optical device such as a camera, and more particularly to a structure for fixing a lens to a lens holding frame.

  Conventionally, in a structure that holds an optical system such as a photographic lens, projection lens, observation system lens, etc., the method of fixing the lens to the lens holding frame is the method of tightening with a presser ring, the plastic barrel is heat / ultrasonic, etc. In order to reduce the size and weight of the lens, there have been many methods for bonding and fixing the lens to the lens holding frame. It is coming.

  Patent Document 1 discloses a structure in which a reservoir for an adhesive whose phase is changed is provided by a lens barrel for bonding two lenses. Patent Document 2 discloses a method in which lenses are bonded to each other and an adhesive flow preventing wall is provided at a contact portion between the lenses. Patent Document 3 discloses a method in which an adhesive flow-out prevention groove is provided at a contact portion between lenses in a configuration in which the lenses are bonded to each other.

JP 2013-83806 A JP 2012-83439 A JP 2011-99900 A

  However, in the prior art disclosed in the above-mentioned patent document, since the flow of the adhesive is not considered in Patent Document 1, in the case of an ultraviolet curable adhesive, the adhesive is not exposed to the ultraviolet lamp. It may flow out and the adhesive may not cure. In addition, an adhesive may enter the rear surface of the lens and affect the optical performance. In Patent Documents 2 and 3, there is a shape to prevent the adhesive from flowing out, but it is impossible to prevent the adhesive from flowing sufficiently because there is a gap, and the gas generated from the adhesive has a diameter. It is also conceivable that the lens may be fogged from time to time.

  Therefore, an object of the present invention is to plastically deform the lens contact surface of the lens holding frame when the lens is inserted into the lens holding frame, thereby eliminating the gap between the lens and the lens barrel, and the adhesive on the lens surface. The structure does not flow.

  Further, the portion where the plastic deformation portion of the lens holding barrel comes into contact with the lens surface is configured to press on a surface different from the surface with the lens barrel, thereby reducing distortion of the lens surface after the lens is inserted. In addition, by forming the plastic deformation part of the lens holding lens barrel into a chamfered part with an outer diameter of the lens, the UV-curing adhesive that wraps around the back of the chamfered part prevents the adhesive from becoming uncured due to the attenuation of UV radiation. It is to provide a lens holding barrel that can be used.

In order to achieve the above object, a lens holding barrel according to the present invention includes:
In the configuration in which the lens is inserted into the lens holding frame and the lens is bonded to the lens barrel, the lens holding frame has a first lens barrel portion that configures the lens at a predetermined position, and an angle different from that of the lens barrel portion. It is a lens holding barrel that has a concave portion for storing an adhesive for bonding the lens barrel and the lens in the phase portion, and has a second body portion that contacts the lens on the inner diameter side of the concave portion of the lens holding frame. Features.

  According to the present invention, in a configuration in which a lens is inserted into a lens holding barrel and the lens is adhered and fixed, the adhesive is prevented from flowing into the back surface of the lens, and the lens is soiled by gas generated from the uncured adhesive. A lens holding frame that prevents this can be provided.

Lens unit cross section Lens holding section enlarged cross-sectional view Lens holding section enlarged cross-sectional view Lens unit front view Lens barrel perspective view Enlarged perspective view of lens barrel frame

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a sectional view showing a state in which a lens is inserted into a lens unit according to an embodiment of the present invention.

  A lens unit according to an embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a cross-sectional view of the lens unit, showing a cross-sectional shape at the position shown in FIG. 2 and 3 are enlarged views of portions A and B of FIG. 5 and 6 are perspective views of the lens barrel 11 in a state where no lens is inserted, and FIG. 6 is a partially enlarged view of FIG.

  The lens unit 10 is a part of a lens unit included in the photographing lens, and lenses L1, L2, and L3 are inserted into the lens barrel 11. In the lens barrel 11, cam followers 12 are equally divided by 120 degrees, and the cam followers 12 are inserted. The lens follower 12 advances and retracts in the optical axis direction by rotating the cam ring by the cam follower 12, a cam ring having a cam groove (not shown), and a guide cylinder having a straight advance groove.

  When the lens L1 is inserted into the lens barrel 11, in order to accurately hold the optical axis of the lens, fitting portions (not shown) are equally arranged at 120 degrees and held in a substantially press-fitted state. . The lens L1 includes a concave surface on the first surface side and a convex surface on the second surface side. The outer diameter portion on the lens first surface side includes a first outer diameter portion L1a and a second outer diameter portion L1b larger than the first outer diameter portion. The second outer diameter portion and the above-described lens barrel 11 fitting parts are inserted in a substantially press-fitted state.

  A flat surface portion L1c is formed on the second surface side of the lens L1, and the flat surface portion L1c and the flat lens receiving portion 11a of the lens barrel 11 come into contact with each other to determine the position of the lens in the lens barrel 11. After the lens L1 is inserted into the lens barrel 11, the claw portion 11c of the lens barrel 11 is deformed by heat to deform and abut on the chamfered portion of the second outer diameter portion L1b of the lens L1.

  When the lens L2 is inserted into the lens barrel 11, in order to accurately hold the optical axis of the lens, the fitting portion 11b is equally spaced by 120 degrees and is held in a substantially press-fitted state. The lens L2 includes a convex surface on the first surface side and a convex surface on the second surface side, and the curvature of the convex surface on the first surface side is larger than the curvature on the second surface side. A chamfer L2b is formed at the outer diameter portion L2a of the lens L2 and the corner portion on the first surface side.

  The lens barrel 11 is provided with three recesses 11d for storing an adhesive for adhering and fixing the lens L2 inserted into the lens barrel 11 at 120 degrees equally. The lens barrel 11 includes a lens contact surface 11f and a second lens contact surface 11e. The lens barrel 11 includes a shelf portion 11g to which the light shielding sheet 13 is attached.

  By sticking the light shielding sheet 13, the adhesive fixing the lens L2 does not pass through the lens L3 and become visible. When the lens L3 is inserted into the lens barrel 11, in order to hold the optical axis of the lens with high accuracy, a fitting portion (not shown) is equally divided by 120 degrees and held in a substantially press-fitted state. The lens L3 has a concave surface on the first surface side and a convex surface on the second surface side. A flat surface portion L3a is formed on the first surface side concave surface of the lens L3. The flat surface portion L3a of the lens L3 is in contact with the flat surface portion 11h of the lens barrel 11, and is positioned in the optical axis direction.

  The lens barrel 11 is provided with three recesses 11i for storing an adhesive for adhering and fixing the lens L3 inserted into the lens barrel 11 at 120 degrees equally. The lens barrel 11 is configured with a light shielding ring 14 fitted to the outer diameter of the lens barrel 11.

As shown in FIG. 4, the bonding portion of L3 that is bonded and fixed to the lens barrel 11 by the light shielding ring 14 is not visible. Here, a process in which the lens L2 is assembled to the lens barrel 11 will be described.
The lens L1 is inserted into the lens barrel 11, and the claw portion 11c of the lens barrel 11 is crushed and fixed by heat caulking. The lens L2 is inserted into the lens barrel 11 by a lens insertion tool (not shown) in the assembly process. At the time of insertion, since the relationship between the lens fitting portion 11d of the lens barrel 11 and the outer diameter L2a of the lens L2 is substantially press-fitted, the lens L2 is superior to the lens barrel 11 by the lens insertion tool. It is pushed in with power.

  The state where the first surface of the lens L2 and the lens contact surface 11f of the lens barrel 11 are in contact is the normal position where the lens L2 is inserted into the lens barrel 11, and the lens L2 is pushed in with the insertion tool until this state is reached. In the process of inserting the lens L2 into the lens barrel 11, the second lens abutting surface 11e is such that the chamfered portion L2b of the lens L2 abuts the first surface of the lens L2 and the lens abutting surface 11f of the lens barrel 11. Contact before.

  When the second lens contact surface 11e comes into contact, the first surface of the lens L2 and the lens contact surface 11f of the lens barrel 11 are not yet in contact. When the lens L2 is further inserted by the lens insertion tool, the tip of the second lens abutting surface 11e of the lens barrel 11 is crushed and deformed, and the first surface of the lens L2 and the lens abutting surface 11f of the lens barrel 11 contact each other. Touch. The lens L2 is in contact with the contact surface 11f of the lens barrel 11 and the deformed second lens contact surface 11e.

  The second lens contact surface 11e has a tip width of about 0.1 mm to 0.3 mm, and an amount of the lens L2 to be crushed is about 0.1 mm to 0.2 mm. By configuring the amount as described above, excessive stress is not applied when it is crushed, and distortion is unlikely to occur on the surface of the lens L2.

  The lens barrel 11 is provided with three recesses 11d for storing an adhesive for adhering and fixing the lens L2 inserted into the lens barrel 11 at 120 degrees equally. The concave portion 11d is formed with a slope on the outer diameter side so that the adhesive can easily flow into the bottom of the concave portion.

  The posture of inserting the lens L2 into the lens barrel 11 is such that the lens barrel 11 is inserted on the upper side and the lens L2 is inserted on the lower side. After the lens L2 is inserted into the lens barrel 11, the lens barrel 11 is reversed. In this state, when the adhesive is poured into the recess 11d, the adhesive flows by gravity, flows along the slope to the bottom of the recess 11d, and is filled between the lens barrel 11 and the lens L2. When the adhesive is of a natural curing type, it is left as it is until the adhesive is hardened. In order to shorten the curing time of the adhesive, it is desirable to use an ultraviolet curable adhesive. When the ultraviolet curable adhesive is used, the time required for curing the adhesive is short, so that the assembly tact time can be shortened.

  After the concave portion 11d is filled with the ultraviolet curable adhesive, ultraviolet rays are projected onto the adhesive from an unillustrated ultraviolet projection lamp to cure the adhesive. After the adhesive has hardened, the light shielding sheet 13 is attached to the lens barrel 11 on the shelf 11g to which the light shielding sheet 13 of the lens barrel 11 is attached. The light shielding sheet 13 covers the adhesive in the adhesive recess 11d so that it cannot be seen through the lens L3. The above is the assembly process of the lens L2.

  A minute gap exists between the lens contact surface 11f of the lens barrel 11 and the first surface of the lens L2, because the first surface of the lens L2 has a convex R shape. When the adhesive is dropped into the adhesive recess 11d and there is no second lens abutting surface 11e, if the adhesive has a low viscosity, the adhesive is placed in a minute gap between the lens and the lens barrel due to capillary action. It flows in and reaches the first surface of the lens L2. In the process of curing the adhesive by irradiating the UV light, the UV energy from the UV lamp is different from the UV energy hitting the adhesive through the inside of the lens and the UV energy directly hitting the adhesive. Yes.

  Some lens glass materials do not significantly transmit ultraviolet rays. When the adhesive reaching the first surface of the lens L2 is hardened by ultraviolet irradiation in the step of curing the adhesive, it becomes ultraviolet light that has passed through the lens, so that it reaches less energy and is difficult to harden.

  As in the present invention, the second lens abutting surface 11e is configured, and the second lens abutting surface 11e is deformed when the lens is inserted, and is configured to abut against the lens. Since the adhesive is blocked by the second lens contact surface 11e, it does not flow into the lens first surface.

  With the above structure, a part of the ultraviolet curable adhesive fixing the lens is not uncured.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

  The present invention relates to a lens holding frame that can be mounted on an optical device such as a camera.

L1-L3 lens, 10 lens unit, 11 lens barrel,
12 Cam follower, 13 Shading mask, 14 Shading ring

Claims (4)

  In a configuration in which a lens is inserted into a lens barrel and the lens is bonded to the lens barrel, the lens barrel has a first lens barrel portion that configures the lens at a predetermined position, and an angle different from that of the lens barrel portion. A lens holder having a concave portion for storing an adhesive for adhering the lens barrel and the lens in the phase portion, and a second body portion that abuts the lens on the inner diameter side of the concave portion of the lens barrel. A lens barrel.   2. The lens barrel according to claim 1, wherein a fitting portion between the lens and the lens barrel is configured except for an angle of a concave portion for storing an adhesive for adhering the lens of the lens barrel.   3. The second body-attached portion has a shape that plastically deforms and contacts the lens when the lens barrel and the lens contact each other at the first lens body-attached portion. The lens barrel described in 1.   4. The lens barrel according to claim 3, wherein the second barrel portion is configured to abut on a surface different from a surface on which the first barrel portion of the lens barrel of the lens abuts.