JPH0333503A - Junction sleeve structure - Google Patents

Abstract

PURPOSE:To stably hold an eyepiece with high fixing accuracy so as to improve durability of a junction by, in two sleeves facing each other, forming their own engagement structures and pressing structures working at the engagement position. CONSTITUTION:An extrapolation sleeve 32 is attached at one end of a lens casing 10 for accommodating an eyepiece 36 therein. Meanwhile, an interpolation sleeve 34 is fixed at one end of a finer casing 12. A pair of engagement grooves 38 are formed on both sides of the interpolation sleeve 34. An engagement structure is constituted of engagement projections 52 and the engagement grooves 38. In addition, a pressure structure is consisted of an abutment surface 54 and an elastic protrusion 40. Therefore, the eyepiece can be stably held in a view finder without any deterioration in fixing accuracy, thereby improving durability of a junction further.

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention is applicable to, for example, a viewfinder of a video camera.
The present invention relates to a structure of a joining sleeve suitable for an EVF (hereinafter referred to as EVF).

[Prior Art] Generally, an EVF of a video camera has an eyepiece lens arranged opposite to the imaging surface of a cathode ray tube. This eyepiece lens is placed in a predetermined position by joining a lens gauge housing the eyepiece lens to a finder casing housing the cathode ray tube.

The structure for joining the two casings is normally configured to join by rotation.

That is, in FIG. 5, a lens gauging 10 housing an eyepiece (not shown) and a cathode ray tube (not shown) are shown.
Noah stores. Each of the intercasings 12 is provided with an outer sleeve 14 and an inner sleeve 16, and by inserting these sleeves 14 and 16 into each other and rotating them, a pair of engagement pins provided on the inner surface of the outer sleeve 14 are connected. 18.18 is engaged with a corresponding pair of fitting grooves 20.20 provided on the outer surface of the inner sleeve 1G, thereby joining both casings 10.12. In this case,
As shown in detail in the enlarged development view of FIG. 6, the fitting groove 20 is
It is composed of an axial guide groove 22, a circumferential engagement groove 24, and a through groove 26 extending circumferentially through the center of the engagement groove, and when the engagement pin 18 passes through the engagement protrusion 28, is the 6th
In the case of FIG. 7B, as shown in FIG. 7, the through groove 26 is elastically expanded and the portion including the engagement protrusion 28 is substantially moved to the left with respect to the right side wall surface X of the through groove 26. It is elastically deformed. Further, when the engagement pin 18 passes through the engagement protrusion 28, the engagement pin 18 is engaged between the lower end curved portion of the engagement groove 24 and the engagement surface of the engagement protrusion 28. Therefore, it is stably positioned at a predetermined position.

As described above, according to the structure of the joining sleeve applied to the electronic viewfinder, the eyepiece can be accurately and stably arranged with respect to the cathode ray tube, and
The eyepiece can be easily attached and detached.

[Problems to be Solved by the Invention] However, the above-mentioned conventional WI structure of a joining sleeve applied to an electronic viewfinder has the following problems.

That is, when the engagement pin 18 passes through the engagement protrusion 28 by 3ffi, when passing through the through groove 26 as described above, the through groove 26 is expanded elastically as described above.
6(b), FIG. 7], therefore, concentrated stress is generated particularly at the upper and lower left corners m26a and 26b of the through hole 26 (FIG. 6(b)). Therefore, if both gaugings 14 and 16 are repeatedly attached and detached, the fitting groove 20 will suffer fatigue damage in the future. Therefore, the above-mentioned structure had drawbacks in terms of rigidity and mechanical strength.
This method has the drawback of making the bonding state of 16 uncertain and unstable, and deteriorating and inhibiting the function of the EVF.

Therefore, an object of the present invention is to improve the joining sleeve supplement so that, for example, when applied to an electronic viewfinder, even if the eyepiece is repeatedly attached and detached, the accuracy of attaching the eyepiece to the EVF will not deteriorate. The objective is to realize a structure that can be held stably and ensure rigidity and mechanical strength.

[Means for Solving the Problems] In order to achieve the above object, in the present invention, one sleeve is inserted into the other sleeve by a predetermined amount and rotated, so that both sleeves are provided with locks that engage with each other. stop structure,
The locking structure is characterized in that the pressing structures that press each other at the locking position are formed at different angles.

In this case, the locking M structure is formed of an engaging protrusion provided on one side of the sleeve and a fitting groove provided on the other side of the sleeve so as not to engage with the engaging protrusion, and the pressing structure is
In order to restrict the insertion position between the end of one sleeve and the other sleeve, it is preferable to configure the restriction formed around the other sleeve to have elasticity on one or both of the surfaces.

Furthermore, a through hole extending a predetermined amount across the axial direction may be provided near the end of the sleeve to impart elasticity to the end of the sleeve.

[Function] The M construction of the joining sleeve according to the present invention allows the locking position of the locking structure provided on one sleeve to be adjusted by inserting a predetermined amount of the other sleeve into one sleeve when both gaugings are engaged. and the pressing structure provided on the other sleeve press against each other, and in this state, when the locking structures of both sleeves are rotated in relative directions, they are elastically locked with each other.

Therefore, the engagement between the engaging protrusion and the mating part causes the through-hole to be elastically deformed by mutual pressure between the end of one sleeve and the regulating wall surface of the other sleeve, thereby keeping the sleeves connected in a stable state. Furthermore, the rigidity and mechanical strength of the fitting ring are not reduced, and fatigue failure can be prevented.

[Embodiments] Next, embodiments of the joining sleeve according to the present invention will be described in detail with reference to the accompanying drawings.

For convenience of explanation, the same reference numerals are given to the same components as those of the conventional structure shown in FIGS. 5 to 7, and detailed explanation thereof will be omitted.

FIG. 1 is an exploded assembly view showing an attachment part of a lens casing housing a fine targeting and an eyepiece according to an embodiment of the present invention, and FIG. 2 is a perspective view of the lens casing viewed from the opposite side. shows.

Reference numeral 32 is one outer sleeve provided at one end of the lens casing 10 that accommodates the eyepiece 36, and reference numeral 34 is provided at one end of the finder casing 12 that accommodates a cathode ray tube (not shown). This is the other insert sleeve.

In addition, a pair of fitting pads 38 are provided on both sides of the inner sleeve 34.
, 38 are formed.

Each sleeve is formed with locking crossways that engage with each other and pressing structures that press against each other at the locking position of the locking supplement at positions that are at different angles.

That is, the locking member is composed of a pair of engaging protrusions 52.52 provided on one outer sleeve 32 and a pair of fitting projections 52.52 provided on the other inner sleeve 34. ing. Further, the pressing structure includes a pair of regulating wall surfaces (hereinafter referred to as contact surfaces 5) provided on the inner periphery of one of the outer sleeves 32.
2) and an elastic protrusion 40.40 provided at the end of the other inner sleeve 34.

Furthermore, this elastic projection 40.40 is connected to the projection 42.42.
and a pair of through grooves 44.44 formed in the cylindrical circumferential direction inside the open end corresponding to the projections 42.42.

In this case, the fitting grooves 38 and 38 are formed by continuously bending the guide groove 46 extending in the axial direction from the open end of the inner sleeve in the circumferential direction, as shown in the enlarged development view of FIG. It is composed of a guide groove 48. A protrusion 49 is formed at the bent portion, and an engagement recess 50 is formed at the tip of the circumferential guide groove 48.

On the other hand, as shown in the perspective view of the lens casing seen from the opposite side in FIG. Dowel pins 52,52 are formed radially oppositely. A pair of abutment surfaces 54 that abut the elastic protrusions 40.40 at the tip of the inner sleeve 34 are formed on both sides between the opposing engagement pins 52.52 to face each other in the radial direction.

When both gauging devices configured in this manner are engaged, the pair of engagement pins 52, 52 are moved into the guide grooves 46 extending in the axial direction of the inner sleeve 34 due to the axial movement of the outer sleeve 32. engage (see FIG. 3) and move to the position shown by the imaginary line in FIG.

Then, when the outer sleeve is rotated in the circumferential direction with the protrusion 42 of the elastic protrusion 40 in contact with the contact surface 54 of the outer sleeve 32, the engagement protrusion 52 becomes the protrusion of the guide groove 48. Since it is located inwardly by δ from the portion 49, rotation is prevented. However, this itt insert sleeve 3
4. By forced rotation, the engagement protrusion 52 overcomes the protrusion 49 and engages with the engagement recess 50 due to the rotational force of the sleeve.

In this case, the inner sleeve 34 has the elastic protrusion 40.4.
The through-hole part is elastically deformed by the axial pressing force generated when getting over the protrusion 49, thereby moving the inner sleeve 34 inward by 8 minutes, and this movement engages the engagement recess 50. The paired engagement pins 52, 52 can be stably held by elastic pressing force in the axial direction.

[Effects of the Invention] As is clear from the embodiments described above, the structure of the joining sleeve according to the present invention is that by rotating one sleeve through the other sleeve by a predetermined distance m4i1i, both sleeves are mutually locked. By configuring the locking structure that fits together and the pressing structure that presses against each other at the locking position of the locking structure to be formed at different angles, the eyepiece remains stable even when the eyepiece is repeatedly attached and detached. The mounting accuracy of the lens to the EVF is stably held without deterioration, and the rigidity and mechanical strength of the fitting groove are not reduced, preventing fatigue failure and increasing the durability of the joint. This has the effect of further improving the

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments. Of course, various design changes can be made without departing from the spirit of the invention.

[Brief explanation of drawings]

Fig. 1 is an exploded assembly view showing an embodiment of the present invention, showing the attachment part of a finder casing and a lens casing housing an eyepiece; Fig. 2 is a perspective view of lens gauging viewed from the opposite direction; Fig. 3 Fig. 4 is an enlarged development view of the fitting groove, and Fig. 5 shows the mounting structure of the joining sleeve in a conventional electronic viewfinder. The perspective views shown in FIGS. 6(a), 6(b), and fc) are all enlarged developed views for explaining the fitting groove and the through groove shown in FIG. 5, and FIG. 6(a) shows the engagement groove. FIG. 6(b) shows the state before the pin is inserted, FIG. 6(b) shows the state when the engaging pin passes through the engaging protrusion, and FIG. 6(C) shows the state when the engaging pin is inserted into the fitting groove. Fig. 7 is an enlarged developed view showing the engaged state; Fig. 7 is Fig. 6(b);
It is an A-AIIJr side view of. 10... Lens gauging 12... Finder casing 14... Outer sleeve 16... Inner sleeve 1
8... Engaging pin 20... Fitting groove 22...
Guide groove 24... Engagement groove 26... Penetration groove
26a, 26b... Corner portion 28... Engaging protrusion 32... Outer sleeve 34... Inner sleeve 36... Eyepiece 38... Fitting groove
40... Elastic protrusion 42... Protrusion
44... Through groove portions 46, 48... Guide groove 4
9...Protrusion 50...Engagement recess 52...Engagement protrusion (gA mating pin) 54...Regulation wall surface (contact surface) FIG. 1 FIG. 1';l "IG. 21- FIG. 5 (G) FIG. (b) 2 (0) FIG. (b) 22- (C)

Claims (3)

[Claims] (1) Both sleeves have a locking structure that locks each other by inserting a predetermined amount of the other sleeve into one sleeve and rotating the sleeve, and a press that presses against each other at the locking position in this locking structure. A structure of a joint sleeve characterized in that the structure and the structure are formed at different angles. (2) The locking structure is formed of an engaging protrusion provided on one side of the sleeve and a fitting groove provided on the other side of the sleeve to engage with the engaging protrusion, and the pressing structure is formed on one side. 2. The joining sleeve according to claim 1, wherein one or both of the ends of the sleeve and a regulating wall formed around the other sleeve to regulate the insertion position of the one sleeve have elasticity. structure. (3) The joint sleeve structure according to claim 1 or 2, wherein a through groove extending a predetermined amount across the axial direction is provided near the end of the sleeve to impart elasticity to the end of the sleeve.