JPS6084517A - Helicoid device - Google Patents

Abstract

PURPOSE:To prevent play with secure and proper restraining force and facilitate the rotation of a lens barrel by providing an engaging screw part for maintaining rotational precision and one thread of an elastic deforming screw part each in a thrust and/or a radial direction. CONSTITUTION:When a thread 3 and a screw groove 6 in a saw tooth shape engages each other, a plate type screw thread 3 contacts a slanting flank 6a to deform elastically, and an outer cylinder 7 is pressed axially with reaction force to regulate the play of a helicoid. Thus, the thread ridges 8 of the outer cylinder 7 are clamped with two kinds of screws 2 and 3 of an inner cylinder 4 with specific forces. Consequently, play of the helicoid in the thrust direction and play in the radial direction are prevented at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a helicoid device, and more particularly to a helicoid device for a lens barrel.

The problem with helicoids in prior art lens barrels is how to eliminate the backlash, but there have been no proposals to date regarding this problem. For example, % Kaisho 56-9710. Various proposals have been made, such as those described in Japanese Utility Model Publication No. 58-118612.

The technique disclosed in Japanese Patent Application Laid-Open No. 56-9710 involves changing all parts of the shape of the helicoid to give a bending action in the thrust direction to the screw capital, and changing the pitch or part of the lead to interfere with the screw capital. Therefore, a means is adopted to completely eliminate play in the threaded portion.

However, since the above-mentioned method (work) causes deformation or interference between the screwed part and the screwed part to forcibly eliminate the backlash, the screwed part becomes stuck and the mirror leg is (b) It has the disadvantage that the movement becomes extremely heavy.Furthermore, it is difficult to employ it because errors in the processing of the shape deformation portion, pitch, or lead deformation portion directly affect the above-mentioned drawback.

The technique disclosed in Japanese Utility Model Application Publication No. 58-102861 involves cutting out a part of the thread of a helicoid, forming a thread of the same pitch in the notch, inserting a tin screw piece, and applying a full spring valve to this screw piece. Does pressing in all thrust directions cause pitch deviation or backlash in the thrust direction? It is something that we try to eliminate.

However, the above means not only complicates the structure, but also complicates the shape of the eye and body of the constituent parts.
The number of man-hours and assembly man-hours increased, leading to higher costs.

According to the technique Q of JP-A-58-118612, a notch is provided in the thread of the helicoid, and this notch has a back that protrudes into the thread groove of the helicoid on the other side and engages with one side of the groove. The purpose is to eliminate backlash by inserting a belly-reducing member.

However, the above means t! , Said Utsukai Sho 58-102
Similar to the technique described in Japanese Patent No. 861, this technique has a complicated structure and has the drawback of high manufacturing and assembly costs. In addition, since positioning in the radial direction depends on the screw-in amount of the screw for one tightening operation, f'L must be adjusted to the clearance of the recoid screw to the other side, making adjustment difficult and automatic. Assembly is also difficult. Furthermore, when the dorsoventral eliminating member is used at one location, there is a drawback that backlash of the helicoid screw cannot be completely eliminated. Furthermore, when installing the back hemorrhoid relief member in two or more places to completely remove the backlash of the helicoid screw, there is no place for the force to escape in the thrust direction, so the side surface of the groove of the helicoid screw on the other side is flat and flat. If it is deformed without any effort, will there be interference on the deformed surface? There was a problem that a so-called helicoid screw jamming phenomenon occurred.

Purpose of the Invention The present invention has been made in view of the above-mentioned problems of the prior art, and its object is to easily and reliably eliminate the thrust in the helicoid screw in all cases and in the radial direction. An object of the present invention is to provide a helicoid device having the following structure.

Composition of the Invention The present invention & technology includes a mating threaded portion for maintaining rotational accuracy, and a threaded portion formed in an elastically deformed hole so as to be pressed in the entire thrust direction and/or radial direction during meshing. By constructing the helicoid device II by having at least one thread of each thread, all of the above objects of the present invention are achieved. Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Explain in detail.

Embodiment FIG. 1 shows a first embodiment of the present invention, and FIG. 1 shows a part of the main part of the present invention in an enlarged manner. As shown in the figure, helicoid device #1 is.

It is composed of an inner cylinder 4 having two types of screw threads 2.3 and a tinted outer cylinder 7 having two types of thread grooves 5.6 corresponding to the screw threads 2 and 3, The threaded portion is configured as a so-called two-thread helicoid (multi-thread thread for focusing; the same shall apply hereinafter).

Two types of screw threads 2 and 3 are formed on the outer peripheral surface of the cylinder 4.
Some of the threads 2 are formed as threads for maintaining rotational accuracy, and cooperate with correspondingly recessed thread grooves 5 of the outer cylinder 7 to maintain rotational accuracy. The meshing screw part for holding is entirely composed of τ.The other screw thread 3 is formed into a plate-like thread part so as to be elastically deformable in the axial direction.
It has a structure in which it contacts (abuts) the inclined side surface (flank) 6a of the sawtooth-shaped thread groove 6 of the outer cylinder 7, which has a corresponding recess.

That is, when the other screw thread 3 and the sawtooth-shaped thread groove 6 mesh with each other, the plate-shaped thread 3 becomes the inclined side ifi+6.
a and is elastically deformed as shown in the figure, and the reaction force from this deformation presses the outer cylinder 7 in the axial direction (rightward in the figure) via the inclined side surface 6a, thereby regulating (resolving) the play of the helicoid. It is constructed in J5. The paraphrase n is
The threaded portion 8 on the outer cylinder 7 is connected to the two types of threads 2 on the inner cylinder 4.
, 3, the Natsumata V is configured to be supported by a predetermined force.
, the occurrence of thrust direction clatter and radial direction deflection in the helicoid is simultaneously prevented. The force that clamps the threaded portion 8 of the outer cylinder 7 is:

Of course, the strength can be set to any desired strength by changing the depth, height, etc. of the plate-shaped screw thread 3 of the inner cylinder 4.

As shown in Fig. 1, the thread 3a at the engagement start portion of the root-shaped thread 3 formed in the elastic deformation point is connected to other threads so as not to come into contact with the hook surface 6a of the corresponding thread groove 6. mountain 3
It is lower (formed or even axially positioned).

The helicoid device IVc has the above configuration.

When the cylinder 4 and the outer cylinder 7 are screwed together, the threaded part 8 of the outer cylinder 7 is held between the two threads 2 and 3 of the cylinder 4, so that the helicoid rotates smoothly without any play. is obtained. In particular, the plate-shaped screw thread 3 that elastically deforms when screwed together has an inclined surface 6a?
When pressed in the axial direction (thrust direction), the upward component of force 44C presses the slope 6a in the radial direction, so
Play in both thrust and radial directions is regulated at the same time, ensuring smooth rotation. Moreover, 8! By arbitrarily changing the thickness, height, etc. of the threaded thread 3, the pressing force can be freely set, so that the force setting range for controlling looseness can be easily expanded. Further, the two screw threads 2.3 that are integrally formed with the inner cylinder 4 are configured so that they themselves have a play regulating function.

It has an extremely simple configuration that completely prevents helicoid rattling, reduces the number of parts, reduces costs, and also simplifies assembly.

Since this is completely prevented by the elastic deformation of the plate-like screw thread 3, the play prevention function is ensured even if the roundness of the cylinders 4 and 7 is poor, and smooth rotational operation can always be expected. Further, since the screw thread 3ak at the engagement start portion of one of the plate-like screw threads 3 is configured so as not to come into contact with the slope 6a of the thread groove 6 to be engaged, assembly of the helicoid device 1 is facilitated.

The figure shown in FIG. 2 is an example of 8th page 2 of this invention. One feature of this embodiment is that the thread groove 6 on the female thread side that is screwed into the plate-shaped thread 3 with elastic deformation points is formed to have a rectangular cross section, and the plate-shaped thread 3 is shown in FIG. 5 1al. The starting end 3a' (j) is formed low and its height gradually increases until it reaches the threaded part 3 with a height H. , a helical thread is shown in a planar line.The upper surface of a portion 3b extending from the starting end (thread cutting part) 3a of the plate-shaped thread 3 to a height HvC is shown in Fig. 3, 1bl. like.

Depending on the progress of screwing, plate-shaped screw thread 3b or female thread valley 11m
The tapered surfaces 3c & C are shaped so that they can be gradually elastically deformed into a predetermined shape by the pressing reaction force from 6b.

The plate-shaped screw (8) having a constant plane height H or later has a thread 3 which is elastically deformed into a substantially hook shape as shown in the rightmost view of Fig. Side (flank) 6 c Press in the k-axis direction and make a bay.

Is the curved soil surface the valley surface 6b of the thread groove 6? The height, thickness, etc. of the thread 3 are set so that it can be pressed in the radial direction. Note that the arrow A in FIG. omitted.

In the above structure as well, as in the first embodiment, the occurrence of backlash in the thrust direction and the radial direction 1'J in the hemicoid is reliably prevented and smooth rotation can be obtained. Also,
Due to the action of the tapered surface 3C, the direction of deformation is restricted to a certain direction, and a desired deformed shape can be obtained. The other functions are the same as those of the first embodiment, so a complete explanation thereof will be omitted.

What is shown in FIG. 4 is an embodiment of the nest 3 of the present invention. The feature of this embodiment is that the elastically deformed plate-shaped screw thread 3 is bent into a "<" shape as shown in FIG.
is formed to have a substantially rectangular cross section as in the second embodiment. Drill the thread groove 6, and remove the entire meshing start part as shown in Figures 4 and 5 (1) and reduce the depth of the root of the thread to a low level (as shown in Figure 1).
When screwed together with the two threads 2.3 of the inner cylinder 4, the troughs 6b of the thread grooves 6 press against the "dog" shaped plate threads 3, causing the plate threads 3 to elastically deform. I'm trying to set it up so that I can get it.

During this deformation, the tip of the plate-shaped screw thread 3 is
bj As shown in the right figure, it comes into contact with the side surface 6C of the thread groove 6, and the upper surface part comes into contact with the valley part 6b of the thread groove 6, and the thrust direction of the helicoid is , the occurrence of backlash in the radial direction is prevented. It goes without saying that by changing the shape, length, thickness, etc. of the plate-like screw thread 3, the turtle-preventing regulating force can be set to any desired value.

According to the above configuration, n ff , the first. As in the second embodiment, it is possible to reliably prevent the occurrence of clattering in the thrust direction and radial direction in the helicoid device 1&C. In particular, according to one embodiment, the plate-shaped screw thread 3 is formed in a "dog-dog" shape nτ
Therefore, it is possible to finely adjust the force for controlling the clasp during elastic deformation, and even if there is some variation in the shape and dimensions of the corresponding thread groove 6, it can be easily accommodated. The other configurations and operations are the same as those of the first embodiment, so their explanation will be omitted.

In each of the above embodiments, the outer circumferential surface of the inner cylinder 4 is formed with one screw thread for maintaining rotational accuracy and one plate screw thread for elastic deformation, but the number of threads is It is not limited to one thread per thread, but can be threaded onto any number of threads. It goes without saying that the cross-sectional shape (tooth profile) of the thread groove 6 in the helicoid device 1 has the same shape in the first to third embodiments, and t may also be good.

The effective regulating force of the invention can prevent smooth rotation of the lens barrel.
It is something that

[Brief explanation of drawings]

Fig. 1 is an explanatory sectional view showing a first embodiment of a helicoid device according to the present invention; Fig. 2 is an explanatory sectional view showing a second embodiment of the invention; FIG. 4 is a cross-sectional explanatory diagram showing the third embodiment of the invention, and FIG. 5 (aJ, (bJ is a detailed explanatory diagram of the essential parts of FIG. ... Helicoid device 2 ... Screw thread for maintaining rotational accuracy 3 ... Plate-shaped thread with elastic deformation pattern. Tokkou applicant Olympus Optical Industry Co., Ltd. Figure 1 Figure 2 Figure 3 Figure 4 4 4 Procedural amendment (voluntary) January 27, 1980 1, Indication of the case 1988 Patent Application No. 193253 2, Name of the invention Helicoid device 3, Person making the amendment Relationship to the case Patent applicant address Tokyo #8 Shibu-ku, Hatagaya 2-43-2-4, Agent 6, Detailed explanation of 1 invention of the specification subject to amendment, Column 7, Contents of amendment (1) Specification, page 10, No. 1 - In the second line, the statement ``Show good luck approximately in a hook shape'' is corrected to ``Show every (hook shape).

Claims (1)

[Scope of Claims] (1) The meshing screw portion for maintaining rotational accuracy and the [9] when meshing.
A helicoid device having at least one threaded portion formed to be elastically deformable so as to be pressed in a thrust direction or a radial direction. (2) The elastically deformable threaded portion is configured such that the thread of the threaded portion is always in contact with the groove side surface of the corresponding female threaded portion to be elastically deformed. The helicoid device described in ILI. (3) The threaded portion formed in the elastic deformation point H is
2. The helicoid device according to claim 1, wherein the thread of the threaded portion is always in contact with the bottom surface of the corresponding thread groove to be elastically deformed. (4) The helicoid device according to claim 1, wherein the threaded portion formed at the elastic deformation point has a bent thread. (5) In the elastically deformable threaded part 1, the thread at the engagement start part of the threaded part is configured to be lower than other threads or shifted in the axial direction. A helicoid device according to claim M1. (6) The elastically deformable threaded portion is characterized in that the thread groove at the meshing start portion of the threaded portion is deeper than the thread grooves at other portions. Helicoid device as described in section.