JPH0599211A - Shaft fixing mechanism - Google Patents

Abstract

(57) [Summary] [Purpose] To manufacture a shaft fixing mechanism that allows the position of the shaft to be adjusted arbitrarily. [Structure] A hole 14 of a base 12 is provided with a taper surface, and a projection 16 of a fixing member 13 is also provided with a taper surface so as to be fitted to the taper surface of the base 12, and at least three portions of the fixing member 13 are bolted 17 Tighten to the base 12 with each bolt 17
The position of the shaft 11 is determined by adjusting the degree of tightening.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft fixing mechanism of a linear guide mechanism incorporated in a photographing lens device such as a television camera.

[0002]

2. Description of the Related Art Conventionally, when fixing a guide shaft of a linear guide mechanism, a guide shaft 2 is attached to a base 1 as shown in FIG.
After the guide shaft 2 is fitted to the base 1, a bolt 3 is inserted from the opposite side of the guide shaft 2,
It is tightened and fixed through. Further, the bolt 3 may be screwed from the circumferential direction of the guide shaft 2.

Further, as shown in FIG. 11, a notch groove 4 and a through hole for the bolt 3 are provided in a part of the base 1, and the guide shaft 2 is fitted into the base 1 and then crosses the notch groove 4 to cross the bolt 3. It may be fixed by tightening through and narrowing the width of the notch groove 4.

Further, as shown in FIG. 12, cutout surfaces 5 and 5'parallel to the axis are cut out at the end portion of the guide shaft 2 so that the cutout surface 5,
5'is provided with a through hole for the bolt 3 in a direction vertical to the base 1
In some cases, the notched surfaces 5 and 5 ′ are joined to the flat portion provided on the above, and the bolts 3 are tightened and fixed.

FIG. 13 is a perspective view of a linear guide mechanism using the above-mentioned fixing mechanism. Two shaft members 6 are arranged in parallel as guide shafts, and the shaft members 6 hold a movable body 8 so as to move straight through a guide mechanism member 7 such as a linear bearing. The moving body 8 is connected to a straight driving screw member 10 such as a ball screw rotated by a motor 9 which is a power source to obtain a straight driving force.

As described above, when the shaft member 6, the linear drive screw member 10 and the two shaft members 6 are used, the parallelism between the shaft members 6 and the linear drive screw member 10 is accurately determined. Otherwise, stress will be generated in each member when the moving body 8 moves, and the torque for rotating the linear drive screw member 10 will increase or the torque fluctuation will increase. Therefore, the power consumption of the motor 9 increases and it becomes difficult to control the position of the moving body 8. Therefore, it is important to accurately determine the parallelism described above.

[0007]

However, in the conventional example, since the position of the shaft member 6 is determined by the processing accuracy of the fitting hole and the mounting surface, the processing accuracy of the member must be increased to improve the position accuracy. .. Since there is a limit to actually improving the processing accuracy, there arise problems that sufficient position accuracy cannot be realized and the cost for increasing the processing accuracy also increases. An object of the present invention is to solve the above-mentioned problems and to provide a shaft fixing mechanism that can easily and accurately determine a position for fixing a shaft.

[0008]

A shaft fixing mechanism according to a first aspect of the present invention for achieving the above object comprises a shaft member and a hole into which the shaft member is fitted, and a taper surface on an outer portion of the hole. And a threaded hole communicating with the bolt insertion hole and having a fixing member having a bolt insertion hole at at least three positions in the circumferential direction and a tapered surface through which the shaft member is inserted and which is in direct or indirect contact with the tapered surface. And a bolt which is inserted into the fixing member and which is screwed into a screw hole of the base member and fastened in the axial direction.

A shaft fixing mechanism according to a second aspect of the present invention for achieving the above object has a shaft member having a tapered surface at an end and a tapered surface in contact with the tapered surface, and at least at three circumferential positions. A fixing member having a bolt insertion hole, a base member having a screw hole that is inserted through the shaft member and communicates with the bolt insertion hole, and is inserted into the fixing member and screwed into a screw hole of the base member. It is characterized by comprising a bolt for tightening in the axial direction.

[0010]

In the shaft fixing mechanism having the above structure, when the bolt is tightened, the fixing member having the tapered surface moves, and the fixing member acts to tighten the shaft by receiving a reaction from the tapered surface of the base member. By adjusting the tightening amount of the bolts in the circumferential direction for each bolt, the shaft position can be determined eccentrically in any direction.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in FIGS. FIG. 1 is a front view of the first embodiment, and FIG.
FIG. 4 is a sectional view taken along the line AA. A base 12 for fixing the shaft 11 is provided with a hole 14 having an inner surface loosely fitted to the shaft 11 and having a tapered surface on the outer side, into which a fixing member 13 is fitted. Further, around the hole 14, three threaded bolt holes 15 for fixing the fixing member 13 are provided. On the other hand, a hole for fitting the shaft 11 is provided in the center of the fixing member 13, and a protrusion 16 having a tapered surface joined to the tapered surface of the hole 14 is provided outside. In addition, a bolt 17 for fixing to the base 12 is provided around the protrusion 16.
The bolt hole 18 for insertion is provided with a diameter of a size with some allowance.

In order to fix the shaft 11 to the base 12, the shaft 11 is inserted through the base 12 and the fixing member 13 is attached to the tip of the shaft 11.
And the taper surface of the base 12 and the taper surface of the fixing member 13 are fitted to each other.
5 Insert and tighten. At this time, all bolts 17
When tightened to the same degree, the taper surface of the fixing member 13 presses the taper surface of the base 12 and receives a reaction from the taper surface of the base 12. This reaction is caused by the protrusion 1 of the fixing member 13.
In order to move 6 in a centripetal manner, the shaft 11 fitted in the protrusion 16 is tightened and fixed.

FIG. 3 is a front view of a modification in which an eccentricity e exists between the center of the shaft 11 and the center of the hole 14, and FIG. 4 is a sectional view taken along the line BB. Hole 14 at the center of shaft 11
When the eccentric amount of eccentricity e is fixed from the center of the base, the taper surface of the protrusion 16 of the fixing member 13 is fixed to the hole 14 of the base 12.
It is sufficient to adjust the amount of entering the taper surface for each circumferential direction. That is, by adjusting the degree of tightening of each bolt 17, the position where the fixing member 13 holds the shaft 11 is changed, and the center of the shaft 11 is eccentric. In this embodiment, there are three bolts 17 for fixing the fixing member 13 to the base 12, but if the number of bolts 17 is four or more, more accurate adjustment can be performed.

FIG. 5 is a front view of the second embodiment, and FIG. 6 is a sectional view taken along the line CC. Hole 14 and fixing member 13
The outer periphery of the protruding portion 16 is not provided with a tapered surface, but the tip end of the shaft 11 and the hole of the protruding portion 16 are provided with a tapered surface. The taper surface of the shaft 11 is adapted to fit into the taper surface in the protrusion 16. The operation and effect of this embodiment are almost the same as those of the first embodiment.

FIG. 7 is a front view of the third embodiment, and FIG. 8 is a sectional view taken along the line DD. The outside of the hole 14 of the base 12 has a diameter such that the ball member 19 can be assembled with the shaft 11, and the inside of the hole 14 is continuous with a tapered surface in the middle. In addition, a taper surface that expands outward is provided inside the tip of the protrusion 16 of the fixing member 13, and the protrusion 16 contacts the ball member 19 after being fitted into the hole 14. The operation and effects of this embodiment are similar to those of the first embodiment.

FIG. 9 is a perspective view of a lens moving mechanism incorporated in a photographing lens device such as a still camera or a television camera to which the present invention is applied. A movable lens group 21 having a lens mounted therein is placed inside the tubular member 20, and is moved by a rectilinear drive mechanism member 23 driven by a motor 22 fixed to the outside of the tubular member 20. ..
A guide mechanism member 24 is provided in front of and behind the moving lens group 21.
One end of the guide shaft 25 is fixed to the movable lens group 21 via the, and the other end is fixed to the tubular member 20 by the shaft fixing mechanism 26, and the movable lens group 21 is held so as to be able to move straight.

As described above, since the photographing lens device is strongly required to be small and lightweight and to save power, it is important to reduce the torque for rotating the linear drive mechanism member 23 and the fluctuation of the torque as described above. Therefore, the effect becomes particularly large. Further, since the moving lens group 21 of the photographing lens device is arranged in the tubular member 20 and the lens moving mechanism is often also configured in the tubular member 20, when the shaft fixing mechanism according to the present invention is used. Since the shaft can be adjusted and fixed from the outside of the tubular member 20, the assembly becomes easy.

[0018]

As described above, in the shaft fixing mechanism according to the present invention, the base, the fixing member, the shaft and the like are provided with tapered surfaces, and the shaft is fixed to the base from at least three directions via the fixing member. When the bolt is tightened to move the fixing member in the axial direction, a reaction force from the tapered surface generates a force for tightening the shaft on the fixing member. At this time, if the amount of movement of the fixing member in each circumferential direction is changed by adjusting the tightening degree of each bolt, the contact position of the tapered surface changes and the position of the shaft also changes.
The position of the shaft can be adjusted arbitrarily.

[Brief description of drawings]

FIG. 1 is a front view of a first embodiment.

FIG. 2 is a sectional view.

FIG. 3 is a front view of a modified example.

FIG. 4 is a sectional view.

FIG. 5 is a front view of the second embodiment.

FIG. 6 is a sectional view.

FIG. 7 is a front view of the third embodiment.

FIG. 8 is a sectional view.

FIG. 9 is a perspective view of an application example.

FIG. 10 is a sectional view of a conventional example.

FIG. 11 is a perspective view of a conventional example.

FIG. 12 is a sectional view of a conventional example.

FIG. 13 is a perspective view to which a conventional example is applied.

[Explanation of symbols]

 11 Shaft 12 Base 13 Fixing Member 14 Holes 15, 18 Bolt Hole 16 Protrusion 17 Bolt 19 Ball Member 20 Cylindrical Member 26 Shaft Fixing Mechanism

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location G02B 7/04

Claims (3)

[Claims] 1. A shaft member, a fixing member having a hole into which the shaft member is fitted, a fixing surface having a tapered surface on an outer side portion of the hole, and bolt insertion holes at least at three circumferential positions, and the shaft. A base member having a tapered surface through which a member is inserted and in direct or indirect contact with the tapered surface and having a screw hole communicating with the bolt insertion hole; and a base member inserted through the fixing member and screwed into a screw hole of the base member. A shaft fixing mechanism comprising: a bolt that is tightened in the axial direction when combined. 2. The shaft fixing mechanism according to claim 1, wherein a ball member is interposed between the fixing member and the tapered surface of the base member. 3. A shaft member having a tapered surface at its end, a fixing member having a tapered surface in contact with the tapered surface and having bolt insertion holes at at least three circumferential positions, and the shaft member is inserted. A shaft fixing mechanism comprising: a base member having a screw hole communicating with the bolt insertion hole; and a bolt that is inserted into the fixing member and screwed into the screw hole of the base member to tighten in the axial direction. ..