JP3745854B2 - Lens holder and lens assembly - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The invention relates to improvements in a lens holder and a lens integrants incorporating lens held in the lens holder holding the lens used in the scanner or the like.
[0002]
[Prior art]
Conventionally, a lens assembly 50 as shown in FIG. 14 is used in a scanner device for transmitting characters and pictures such as printed matter or taking them into a personal computer. The lens assembly 50 has a configuration in which two convex lenses 51 and 52 are placed in a cylindrical member 53 with their planar sides facing each other and pressed by a contact member 54.
[0003]
When the lens assembly 50 is assembled and fixed, the convex lens 51 is first placed on the protrusion 55 of the cylindrical member 53, and then the interposition member 56 is placed on the convex lens 51. Next, the convex lens 52 is placed on the interposition member 56, and finally the contact member 54 is placed on the convex lens 52 and fixed by adhesion. At the time of this assembly, if it is uneasy to fix only by bonding the last contact member 54 alone, the fixing is also performed when the convex lens 51, the interposition member 56, and the convex lens 52 are assembled.
[0004]
[Problems to be solved by the invention]
However, the conventional lens assembly 50 has a large number of parts, takes time for assembly, and is expensive. Moreover, since the interposition member 56 that maintains the distance between the biconvex lenses 51 and 52 is configured to be placed on the convex lens 51, the horizontal accuracy tends to be lowered. When the horizontal accuracy is lowered, the distance between the biconvex lenses 51 and 52 is not constant, resulting in variation in the interval between products.
[0005]
In addition, due to adhesive fixation, the adhesive force is likely to change due to a temperature change, and a phenomenon occurs in which the abutting member 54 is detached or the biconvex lenses 51 and 52 are taken together with a change with time. Furthermore, this adhesive fixing is a major factor in further increasing the assembly time because the parts are as small as several millimeters.
[0006]
The present invention aims to provide a lens holding member and lenses integrants which may greatly reduce the embedded time. Furthermore, an object of the present invention is to provide a lens holder and a lens assembly that can improve the distance accuracy between two lenses that are stacked at a distance in the axial direction.
[0007]
[Means for Solving the Problems]
In order to achieve such an object, the invention described in claim 1 includes a holding portion made of a cylindrical wall that holds the lens, and a central hole that is surrounded by the holding portion and allows light passing through the lens to pass therethrough. The holding portion allows the projection receiving portion notched on the side facing the central hole to receive the projection protruding on the outer periphery in the radial direction provided on the lens, and the rotation of the projection inserted into the projection receiving portion. The rotation guide unit, the rotation prevention unit that the protrusion abuts to prevent the rotation of the lens, the placement unit that places the projection that abuts against the rotation prevention unit, and the rotation prevention unit abuts against the rotation prevention unit. A positioning portion having elasticity that presses the blocked protrusion to the rotation blocking portion side and the placement portion side, and forms a tapered surface at each of the rotation side front end and the rotation side rear end of the projection of the lens; Lens protrusion at the pressing protrusion To but side for positioning and holding the projections of the insert to come side and the lens, has a tapered surface in contact with the tapered surface of the tapered surfaces and rotation-side rear end of the rotation-side tip of the projection, respectively the formed lens holder .
[0008]
According to a second aspect of the present invention, in the lens holder according to the first aspect, the protrusion receiving portion, the rotation guide portion, the rotation prevention portion, the placement portion, and the positioning portion are respectively provided in the central hole. A plurality are provided symmetrically with respect to the center by 180 degrees. Furthermore, in the invention according to claim 3, in the lens holder according to claim 1 or 2, the projection receiving portion, the rotation guide portion, the rotation prevention portion, the mounting portion, and the positioning portion are respectively light-transmitted. The distance between the two lenses to be placed is maintained by the thickness of the placement forming portion that is provided in the axial direction and forms both placement portions.
[0009]
Furthermore , in the invention described in claim 4 , in the lens holder described in claim 1, 2, or 3 , the holder is formed of a resin material having elasticity.
[0010]
According to a fifth aspect of the present invention, the lens holder according to any one of the first to fourth aspects includes a protrusion projecting in the radial direction, and two concave portions provided on the outer periphery and symmetrically 180 degrees. The lens which has is built.
[0011]
When assembling the lens into the lens holder, first, a gripping portion such as a jig is inserted into a recess provided symmetrically around the outer periphery of the lens, and the lens is grasped and inserted into the holding portion of the lens holder.
[0012]
At this time, Komu placed so as to face the protrusion receiving portion of the holding portion a projection of the outer periphery of the lens.
[0013]
Then, the inserted lens is rotated along the rotation guide portion. At this time, the projection of the lens rotates against the elastic force while expanding the positioning portion of the holding portion. The rotation is blocked by hitting the rotation blocking portion. At this time, the lens is placed on the placement portion and is pressed to the rotation prevention portion side and the placement portion side by the elastic force of the positioning portion. In this way, the lens is incorporated into the lens holder and becomes a lens assembly.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Examples of embodiments of the present invention will be described below with reference to FIGS. Incidentally, it will be described with reference initially for the first embodiment the lens holding member and lenses integrants from Figure 1 in Figure 10.
[0015]
The lens assembly 1 is for reading by a scanner, and is composed of a resin lens holder 2 and two lenses 3 and 3. The lens holding body 2 includes a holding portion 4 formed of a cylindrical wall that holds the lenses 3 and 3 and a central hole 5 that is surrounded by the holding portion 4 and allows light passing through the lenses 3 and 3 to pass therethrough. ing. Although the lens holder 2 is made of polycarbonate, other various resin materials such as ABS resin can be used.
[0016]
The holding portion 4 allows the projection receiving portion 11 notched on the side facing the central hole 5 to receive the projection 6 provided on each lens 3 and the rotation of the projection 6 fitted in the projection receiving portion 11. The rotation guide portion 12 that rotates, the rotation prevention portion 13 that the protrusion 6 abuts to prevent the rotation of the lens 3, the mounting portion 14 that places the protrusion 6 that abuts the rotation prevention portion 13, and the rotation There is provided a positioning portion 15 having elasticity that presses against the movement preventing portion 13 against the rotation preventing portion 13 and the mounting portion 14 side.
[0017]
In addition, the protrusion receiving part 11, the rotation guide part 12, the rotation prevention part 13, the mounting part 14, and the positioning part 15 are each provided in two 180 degrees symmetrically about the center of the center hole 5. In addition, a total of four are provided because they are provided in the optical axis direction.
[0018]
In addition, each placement portion 14 is formed on both side surfaces of a placement formation portion 16 provided substantially at the center of the holding portion 4 so as to surround the central hole 5. The placement forming portion 16 holds the distance between the lenses 3 and 3. Further, the rotation guide portion 12 is provided in a wall through hole 17 portion that penetrates the wall of the holding portion 4. In addition, the positioning portion 15 is a bridge-like portion that bridges the inside of the wall through-hole 17 in the circumferential direction, and a pressing protrusion 18 that protrudes toward the placement portion 14 is provided at the approximate center of the bridge-like portion. It has been.
[0019]
Further, the mounting forming portion 16 provided in the holding portion 4 is a step formed so as to avoid contact between the lens 3 and the slope portion 16a that allows the light passing through the center hole 5 to pass through a wide angle. It has the part 16b and the mounting part 14 mentioned above in which the lens 3 is mounted.
[0020]
Moreover, the front-end | tip part of the press protrusion 18 is formed so that it may incline. That is, the inclination angle α of the taper 18a on the side where the protrusion 6 of the lens 3 is inserted is 30 degrees, and the inclination angle β of the tapered surface 18b on the side where the protrusion 6 of the lens 3 is positioned and held is 45 degrees. And the flat part 18c is provided between both the taper surfaces 18a and 18b.
[0021]
The lens holder 2 is provided with a pedestal portion 19 serving as a pedestal for attachment to the scanner device at one end in the axial direction, and a reference portion 20 serving as a reference for assembly is provided on the outer peripheral side surface along the axial direction. It has been.
[0022]
Next, the lens 3 will be described.
[0023]
This lens 3 is an acrylic molded product, and is an aspherical lens whose both surfaces are aspherical. One convex surface 21 is a convex aspherical surface, and the other concave surface 22 is a concave aspherical surface. Two protrusions 6 are provided on the outer periphery of the lens 3 symmetrically by 180 degrees. The lens 3 is further provided with two recesses 23 symmetrically by 180 degrees.
[0024]
The entire diameter R1 of the lens 3 is 7 mm, and the diameter R2 of the circular portion of the lens 3 is 6 mm. Further, the diameter R3 of the spherical surface portion including the aspheric surface of the convex surface 21 is 5 mm, the diameter R4 of the aspheric surface portion is 4 mm, and the diameter R5 of the usable range as the aspheric surface is 3.7 mm. On the other hand, the diameter R6 of the circular part on the concave surface 22 side is 5.6 mm, the diameter R7 of the spherical part including the aspherical surface is 4.7 mm, and the diameter R8 of the aspherical part is 3.2 mm, which can be used as an aspherical surface. The range diameter R9 is 2.8 mm.
[0025]
As described above, the aspherical portion occupies about 70 to 80% (R4 / R3, R8 / R7) in diameter, that is, about 50 to 64% in terms of area, with respect to the spherical portion. Further, flat portions 24 and 25 are provided outside the spherical portion, respectively.
[0026]
Further, a slight taper surface 6a is provided at the tip of the protrusion 6 on the rotation side, and a taper surface 6b larger than the taper surface 6a is provided at the rear end of the rotation side. The inclination angle γ of the tapered surface 6b is the same as the inclination angle β of the tapered surface 18b of the pressing protrusion 18, that is, 45 degrees here.
[0027]
Note that the thickness of the lens 3, that is, the thickness M1 of the central portion thereof is 2 mm, and the depth M2 of the recess 23 is 0.5 mm. Further, the basic radius when forming the aspherical surface of the convex surface 21 is about 4 mm, and the basic radius of the concave surface 22 is about 33 mm. Further, the gate at the time of molding is provided on the outer periphery in the radial direction of one protrusion 6. Furthermore, the molding die used at the time of molding is a split die that is divided into left and right along the NN line in FIG.
[0028]
The lens 3 is assembled into the lens holder 2 configured as described above as follows.
[0029]
First, the lens 3 is grasped using a jig. At this time, the recesses 23 and 23 are used. Then, the projection 6 of the lens 3 is inserted into the projection receiving portion 11 of the lens holder 2. Thereafter, the lens 3 is rotated along the rotation guide portion 12 by rotating the jig. Then, the protrusion 6 of the lens 3 abuts against the pressing protrusion 18 provided on the positioning portion 15, but the positioning portion 15 can be elastically deformed, so that the protrusion 6 further rotates while elastically deforming the positioning portion 15. Then, the projection 6 hits the rotation preventing portion 13 and the rotation of the lens 3 is prevented. In this state, the pressing protrusion 18 returns to the vicinity of the original position, and the tapered surface 18 b presses the tapered surface 6 b of the protrusion 6. As a result, the pressing protrusion 18 presses the protrusion 6 of the lens 3 toward the placement portion 14 side and the rotation prevention portion 13 side.
[0030]
In this state, the jig is separated from the lens 3. The other lens 3 is assembled from the opposite side of the lens holder 2, but the same procedure is used. In this way, the two lenses 3 can be incorporated and fixed to the lens holder 2 basically by two operations.
[0031]
When the incorporation of the lens 3 is completed, the projection 6 of the lens 3 has a slight gap L1 from the arm portion of the positioning portion 15 as shown in FIG. It will be a thing. That is, the protrusion 6 of the lens 3 is in contact with the positioning portion 15 only by the pressing protrusion 18 and is not in contact with the placement portion 14. As a result, the flat portion 25 of the lens 3 is reliably placed on the placement portion 14, and the distance accuracy between the lenses 3 and 3 is ensured by the placement formation portion 16. Further, the lens holder 2 of the first embodiment can be formed with high accuracy without forming air around the pressing projection 18 when the positioning portion 15 is formed.
[0032]
Next, the lens built-in body 31 and the lens holding body 32 of 2nd Embodiment are demonstrated based on FIGS. 11-13. Since this lens assembly 31 uses the same lens 3 as the lens assembly 1 of the first embodiment, description of the lens portion is omitted. Further, parts having the same structure as in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified.
[0033]
Similarly to the first embodiment, the lens assembly 31 of the second embodiment is also used in the scanner device, and is an extremely small component having a diameter of about 10 mm. As shown in FIGS. 12 and 13, the lens holding body 32 of the lens assembly 31 has a shape in which the positioning portion 33 is a part of the bridge-shaped positioning portion 15 of the first embodiment. That is, the portion on the insertion side is cut out from the portion where the pressing protrusion 18 is formed.
[0034]
In the second embodiment, even when the lens holder 32 is made of a hard material, for example, a polycarbonate containing 20% glass, a sufficient amount of deflection of the positioning portion 33 can be secured, and both elastic force and accuracy can be secured. It will be a thing.
[0035]
In each of the embodiments as described above, in order to make the mounting portion 14 on which the inner periphery of the wall portions of the lens holders 2 and 32 and the flat portion 25 of the lens 3 are mounted more accurately than the other portions, mirror finishing Is given. However, if the accuracy at the time of molding is improved, such accuracy improvement processing becomes unnecessary.
[0036]
Each embodiment described above is an example of a preferred embodiment of the present invention, but is not limited to this, and various modifications can be made without departing from the scope of the present invention. For example, the material of the lens holders 2 and 32 is preferably glass-filled, for example, 20% glass-filled polycarbonate when it is desired to improve accuracy, and ABS resin is used when it is desired to have a large elastic force. However, other various resin materials can be employed. Furthermore, an aspherical lens made of acrylic is used as the lens 3, but it may be a glass lens or a spherical lens.
[0037]
Further, when the lens 3 is incorporated in the lens holders 2 and 32, if the positioning portions 15 and 33 are hard and sufficient deflection cannot be obtained, the lens holders 2 and 32 are warmed to secure the deflection amount. You may do it. Such a treatment can be applied when the lens holders 2 and 32 are made of a resin material or the like that becomes soft when heated.
[0038]
Further, in each embodiment, two lenses 3 are incorporated, but a lens holding body and a lens assembly in which only one lens 3 is incorporated may be used. Furthermore, the number of protrusions 6 of the lens 3 may be one instead of two, and one protrusion receiving portion 11 or the like of the lens holders 2 and 32 may be provided for each lens 3. Further, instead of one each, three or more protrusions 6 may be provided and the number corresponding to the number may be provided. Further, when two projections 6 are provided on the lens 3, it may be asymmetrical rather than 180-degree symmetric.
[0039]
Further, the number of the concave portions 23 provided in the lens 3 may be one instead of two, or three or more. However, it is most preferable to provide two concave portions 180 symmetric with respect to the handling of the lens 3.
[0040]
Further, the tapered surfaces 18a and 18b of the pressing protrusions 18 of the lens holders 2 and 32 may be set to other values instead of 30 degrees or 45 degrees. The inclination angle α of the tapered surface 18a is preferably 15 to 45 degrees, and most preferably about 30 degrees, considering the ease of insertion of the protrusion 6 and the protruding amount of the pressing protrusion 18. The tapered surface 18b is preferably the same as the tapered surface 6b on the projection 6 side, and the inclination angle β is preferably 35 to 55 degrees, and most preferably around 45 degrees, considering the pressing component force.
[0041]
【The invention's effect】
As described above, in the lens holder according to the first aspect, an adhesive for fixing the lens to be incorporated is not required, and no other parts are required for lens incorporation. As a result, when used for a lens assembly, the assembly time can be greatly reduced. In addition, in this lens holder, since the positioning portion has a bridge shape, the positioning portion can be easily molded, and a highly accurate positioning portion can be formed. In addition, since it has a bridge shape, it is not easily bent even when a strong impact force is applied from the outside, and the incorporated lens can be stably held for a long time.
[0042]
In the second aspect of the invention, the plurality of protrusion receiving portions and the like are provided symmetrically by 180 degrees with respect to the center of the center hole, so that the holding of the lens when the lens is incorporated is stabilized. Furthermore, in the invention described in claim 3, it is possible to provide a lens holder that can increase the distance accuracy between both lenses to be incorporated, and can improve the quality when the lens is assembled.
[0043]
Et al is, in the invention of claim 4 wherein, the holding portion is formed of a resin material having elasticity, will have inevitably elasticity positioning portion. For this reason, the formation of the positioning portion is greatly simplified.
[0044]
In the lens assembly according to the fifth aspect , the handling becomes simple and the lens can be easily assembled. In particular, it is advantageous for handling a miniaturized lens, for example, handling such as grasping and rotating .
[0045]
In addition, when the lens is incorporated into another member, the projection can be used to incorporate the lens, so that the incorporation can be simplified.
[Brief description of the drawings]
FIG. 1 is a front view of a first embodiment of a lens assembly according to the present invention.
FIG. 2 is a plan view seen from the direction of arrow II in FIG.
3 is a cross-sectional view taken along the line III-III in FIG.
4 is a front view of a lens holder used in the lens assembly of FIG. 1. FIG.
5 is a plan view seen from the direction indicated by the arrow V in FIG.
6 is a bottom view seen from the direction of the arrow VI in FIG. 4. FIG.
7 is a front view of an essential part of a positioning portion of the lens holder in FIG. 4;
8 is a plan view of a lens used in the lens assembly in FIG. 1. FIG.
9 is a cross-sectional view taken along line IX-IX in FIG.
10 is a partial side view of the lens of FIG. 8, where (A) is a view seen from the direction of arrow A in FIG. 8, and (B) is a view seen from the direction of arrow B in FIG.
FIG. 11 is a cross-sectional view of a second embodiment of the lens assembly according to the present invention, corresponding to FIG.
12 is a plan view of a lens holder used in the lens assembly of FIG. 11, and is a view seen from the direction of arrow XII in FIG.
13 is a partial side view seen from the direction of arrow XIII in FIG.
FIG. 14 is a cross-sectional view of a conventional lens assembly.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Lens assembly 2 Lens holding body 3 Lens 4 Holding part 5 Center hole 6 Protrusion 11 Protrusion receiving part 12 Rotation guide part 13 Rotation prevention part 14 Mounting part 15 Positioning part 16 Mounting formation part 17 Wall through-hole 18 Pressing protrusion 23 Recess

Claims (5)

A holding portion comprising a cylindrical wall for holding the lens, and a central hole for passing light passing through the lens while being surrounded by the holding portion, the holding portion has a diameter provided on the lens. A projection receiving portion cut out on the side facing the central hole to receive the projection protruding outward in the direction, a rotation guide portion allowing rotation of the projection fitted in the projection receiving portion, and rotation of the lens A rotation preventing portion against which the protrusion abuts to prevent movement; a placement portion for placing the protrusion abutting against the rotation prevention portion; and the protrusion against which the rotation is abutted against the rotation prevention portion. A positioning portion having elasticity to press against the rotation prevention portion side and the placement portion side, and
The rotation guide portion is provided in a wall through-hole portion that penetrates the wall, the positioning portion is a bridge-like portion that bridges the inside of the wall through-hole in the circumferential direction, and is described above at a substantially center of the bridge-like portion. Provide a pressing projection that protrudes to the mounting part side,
A taper surface is formed at each of the rotation-side tip and the rotation-side rear end of the lens protrusion, and the protrusion on the side where the lens protrusion is inserted and on the side where the lens protrusion is positioned and held. And a tapered surface in contact with the tapered surface at the distal end of the rotational side and the tapered surface at the rear end of the rotational side .  A plurality of the protrusion receiving portion, the rotation guide portion, the rotation blocking portion, the placement portion, and the positioning portion are provided symmetrically with respect to the center of the central hole by 180 degrees. The lens holder according to claim 1.  The mounting formation in which the protrusion receiving unit, the rotation guide unit, the rotation blocking unit, the mounting unit, and the positioning unit are provided in the optical axis direction to form the mounting units. 3. The lens holding body according to claim 1, wherein the distance between the two lenses to be mounted is held by the thickness of the portion. Claim 1, 2 or 3 lens holding member, wherein the formed resin material having elasticity the holding portion. The lens holding body according to any one of claims 1 to 4, wherein a lens having a projection protruding in the radial direction and two concave portions provided on the outer periphery and symmetrically by 180 degrees is incorporated. The lens built-in.

Images