JPH0680326B2 - Elastic pivot - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an elastic pivot interposed between a fixed body and a rotary body, and particularly prevents damage to a leaf spring portion due to radial displacement. It is a thing.

<Prior Art> When a rotating body is pivotally attached to a fixed body so that the rotating body can swing by a fixed angle, various bearings suitable for the purpose of use are supported at this pivoting portion in order to facilitate smooth swinging of the rotating body. Is installed. For example, rolling bearings that require lubrication cannot be adopted because general maintenance is almost impossible under special environments such as outer space. A type of elastic pivot that allows movement is used.

This elastic pivot is incorporated in a reflected light scanning device that changes the reflection direction of a light beam by a small amount.
As shown in FIG. 10, the fork-shaped bracket 1 fixed to a frame (not shown) and the mirror holder 3 to which the reflecting mirror 2 is attached are connected to each other via an elastic pivot 4. Can swing about the elastic pivot 4 with respect to the bracket 1 within a permissible range of elastic torsional deformation. An operation rod 5 attached to an actuator (not shown) on the mirror holder 3
The upper end of is rotatably connected via a pin 6,
The mirror holder 3 swings around the elastic pivot 4 by the operation of this actuator, but since elastic twist is constantly applied to this mirror holder 3, the reflection direction of the light beam (not shown) is accurate to the operation amount of the actuator. Can be changed according to.

FIG. 11 showing an example of a fracture structure of the simplest structure of the elastic pivot that is connected to the fixed body and the rotating body and can assist the swinging of the rotating body with respect to the fixed body, and at the time of manufacturing this elastic pivot. As shown in FIG. 12 showing the disassembled state, FIG. 13 showing the cross-sectional structure thereof, and FIG. 14 showing the shape of the left side surface thereof, conventionally, an inner cylinder 101 and an outer cylinder to which this inner cylinder 101 is fitted are attached. 102, a leaf spring 104 inserted into a first fitting groove 103 formed on the inner peripheral surface of the inner cylinder 101 at a distance of 180 degrees from each other and welded, and 90 relative to the first fitting groove 103. It is made by combining a pair of leaf springs 106, which are inserted in a second fitting groove 105 formed on the inner peripheral surface of the inner cylinder 101 and are welded by shifting the phase. Recesses 107 are formed on both end sides of the outer peripheral surface with the center of the inner cylinder 101 as a boundary over approximately half the circumference. Make up 108. Both circumferential ends of the recesses 107 communicate with a pair of elongated holes 109 formed along the longitudinal direction of the inner cylinder 101, and the inner cylinder 101 and the outer cylinder 102 are fitted to each other to form a semi-arc shape. After brazing the joint portion 110 of these, both ends thereof are cut off, and the long hole 109 remains as a part of the gap portion 108. After the brazing work, an annular groove 111 is engraved in the central portion of the outer cylinder 102 so that it is in communication with the gap 108.

<Problems to be solved by the invention> Normally, the elastic pivot allows relative rotation between the fixed side and the rotating side by elastic bending deformation of the leaf spring, and the rigidity of the leaf spring is set according to the usage conditions. Has been done. For this reason, if an unexpected stress is applied, there is a possibility of destruction. For example, if you try to incorporate this elastic pivot into the antenna pointing control mechanism mounted on the communication satellite,
When the satellite is launched, the inertia of the oscillating part becomes large and a large force is applied to the leaf spring due to vibrations and the like, which may cause an accident.

As the stress that adversely affects the leaf spring, axial compression and radial shear are important in addition to bending accompanying the swing of the main body. Relative rotation between the fixed body and the rotating body can be performed by appropriately setting the width (circumferential length) of the elongated hole 109 shown in FIGS. 11, 12, and 13 for bending stress. It becomes possible to regulate a certain amount to a constant angle, and the bending stress applied to the leaf spring 104 can be kept below a predetermined value. Further, for the axial compressive stress, the annular groove 11 shown in FIGS. 11 and 13 is used.
By appropriately setting the width of 1 (axial length), the relative axial displaceable amount between the fixed body and the rotating body can be restricted to a certain amount or less, and the leaf spring 104 is loaded. The compressive stress can be kept below a predetermined value.

However, the conventional elastic pivot cannot control the radial shear stress at all, and it is impossible to prevent the leaf spring from being damaged when a force that bends the axial center of the elastic pivot is applied. It is possible.

In view of the above-mentioned problems in the conventional elastic pivot, it is an object of the present invention to provide an elastic pivot intended to improve reliability by preventing damage to the leaf spring against an external force that adversely affects the leaf spring. And

<Means for Solving Problems> An elastic pivot according to the present invention has a cylindrical body in which one side is connected to a fixed body and the other side is connected to a rotating body with an annular groove formed on an outer peripheral surface as a boundary. A pair of groove portions formed along the axial direction on the inner peripheral surface of the main body and communicating with the annular groove, and a semi-arcuate shape concentrically opening to one end surface side of the main body and the annular groove A first gap portion, and a semicircular arc-shaped second gap portion concentric with the main body in the opposite direction to the first gap portion and opening to the other end face side of the main body and the annular groove,
A fixed body of the main body, which is connected to the fixed body in an elastic pivot having both ends integrally connected to an inner peripheral surface of the main body and at least two leaf spring portions intersecting each other. The connecting portion and the rotating body connecting portion of the main body connected to the rotating body are overlapped with each other with a constant gap therebetween, and the fixed body connecting portion and the rotating body connecting portion are mutually displaced by a radial relative displacement. It is characterized in that a radial displacement regulating stopper capable of abutting against is provided.

<Operation> The rotating body is allowed to rotate with respect to the fixed body due to the elastic deformation of the leaf spring portion. Further, when the rotary body is displaced with respect to the fixed body such that its axis is bent, when the displacement amount exceeds a predetermined value, the radial displacement regulation stopper of the rotary body coupling portion is provided to the radial displacement regulation stopper of the fixed body coupling portion. Abut and prevent further displacement.

<Embodiment> FIG. 1 showing a sectional structure of an embodiment in which an elastic pivot according to the present invention is applied to a double end type, FIG. 2 showing a right side surface thereof, and an enlarged main part in FIG. As shown in FIG. 3, outer cylinders 12 and 13 each having a three-section cylindrical shape are integrally joined and fitted to the outer peripheral surface of the cylindrical inner cylinder 11 by welding or adhesion such as brazing. Form a cylindrical body as a whole. At the left and right ends of the outer peripheral surface of the inner cylinder 11, a groove 14 is formed as a first gap portion having a semicircular arc shape.
Are formed in the same phase, and a groove 15 is formed in the center of the outer peripheral surface of the inner cylinder 11 as a second gap having a semi-arcuate shape in the opposite phase. These grooves 14 and 15 respectively include a pair of groove portions 16 cut out in the longitudinal direction of the inner cylinder 11 (left and right direction in FIG. 1) and an annular groove 17 formed between the outer cylinders 12 and 13 adjacent to each other. Are communicating with each other. The pair of outer cylinders 12 located at both ends of the inner cylinder 11 and the outer cylinder 13 located in the center of the inner cylinder 11 constitute a fixed body connecting portion in which either one is connected to a fixed body (not shown). On the other hand, the other constitutes a rotating body connecting portion connected to a rotating body (not shown). A pair of parallel leaf springs 18 corresponding to the outer cylinder 12 are laid over both ends of the inner circumference of the inner cylinder 11, and similarly, a leaf spring 19 orthogonal to the leaf springs 18 is formed.
Is provided at the center of the inner circumference of the inner cylinder 11. Due to the elastic bending deformation of these leaf springs 18 and 19, relative rotation between the outer cylinder 12 and the outer cylinder 13 is allowed, and this relative rotatable angle α is restricted by the width of the groove portion 16. That is, the groove
By setting the width of 16 appropriately, the relative rotation range between the outer cylinder 12 and the outer cylinder 13 can be regulated without causing damage to the leaf springs 18 and 19.

In this embodiment, the annular groove 17 is formed in a stepped manner to appropriately set the gap S at the overlapping portion as the radial displacement restricting stopper, so that the relative displacement that causes the inner cylinder 11 to bend is different from that of the outer cylinder 12. When the cylinder 13 is raised, the overlapping portions come into contact with each other to prevent further displacement. That is, the relative displacement in the radial direction between the outer cylinder 12 and the outer cylinder 13 is allowed by the amount of the gap S, and the shear stress applied to the leaf springs 18 and 19 becomes too large, so that the leaf springs 18 and 19 may be damaged. There is no fear.

Further, the outer cylinders 12 and 13 are allowed to be axially displaced relative to each other across the gap T of the annular groove 17, so that the outer cylinders 12 and 13 are suppressed to have a relative axial displacement below the gap T. Becomes That is, even if a large axial compressive stress acts between the outer cylinder 12 and the outer cylinder 13, they cannot be displaced by the gap T or more, and the leaf springs 18 and 19 can be prevented from buckling.

As shown in FIGS. 4 to 7 showing an example of a method of manufacturing such an elastic pivot, first, leaf springs combined in a cross shape are first formed.
While the 18, 19 are engaged with the mounting groove 20 formed on the inner peripheral surface of the inner cylinder 11, these are integrated by welding, bonding or the like (fourth
(See the drawing), and the entire outer peripheral surface of the inner cylinder 11 is scraped off by turning or the like (see FIG. 5). Further, while engraving the annular grooves 14 and 15 and forming the groove portion 16, the outer cylinders 12 and 13 are prepared (see FIG. 6), and these outer cylinders 12 and 13 are inserted into the inner cylinder 11 for welding or bonding. These are integrated by, for example, but in the present embodiment, a bonding agent injection hole 21 for pouring a brazing material or an adhesive into the bonding gap portion between the inner cylinder 11 and the outer cylinders 12 and 13 is previously formed in the outer cylinders 12 and 13. The bonding agent injection hole 21 is finally closed by this bonding agent (see FIG. 7). In this case, in order to accurately set the gap T of the annular groove 17 between the outer cylinders 12 and 13, the gap portion in FIG.
It is convenient to carry out the joining work with a spacer of a predetermined size sandwiched between 22.

In this embodiment, in order to prevent dust or the like from being caught in the annular groove 17, a part of both end portions of the outer cylinder 13 is cut out to form a claw-shaped projection 23, and the groove portion 16 Groove wall or outer cylinder 12,1
By subjecting the wall surface of the overlapping portion forming the gap S of 3 and the groove wall forming the gap T of the annular groove 17 to solid lubrication treatment, it is possible to reduce the twisting and the like at the time of abutting them. Further, in the present embodiment, the case where the leaf springs consist of three pairs has been described. However, as shown in FIG. 8 showing the sectional structure of another embodiment of the elastic pivot according to the present invention, two pairs of them are perpendicular to each other. It is also possible to form the plate springs 18 and 19 only, and in short, it suffices if at least two or more plate spring portions are in an intersecting state. The same reference numerals as those used in the above-described embodiment are used for the portions having the same functions. In this embodiment, the outer cylinders 12 and 13 also have a two-part structure, and the annular groove 17 has a simple stepless shape. Therefore, end plates 24 are integrally attached to both ends of the inner cylinder 11, and displacement restriction stoppers are provided between the end plates 24 and the outer cylinders 12, 13 and the inner cylinder 11 for displacement amount regulation. Gap S,
Although the respective Ts are formed, it is naturally possible to set the gap T in the annular groove 17.

As shown in FIG. 9 showing a sectional structure of still another embodiment of the elastic pivot according to the present invention, a flange pipe for connecting a fixed body or a rotating body (not shown) to one of the outer cylinders 12 and 13.
25 may be integrally fitted, and a gap S may be formed between the inner peripheral surface of the flange tube 25 and the outer peripheral surface of the outer cylinder 12 by using the flange tube 25 as a radial displacement regulation stopper. By forming this gap S, the relative radial displacement of the outer cylinders 12, 13 is restricted to a certain amount or less, as in the embodiment shown in FIG.
The shearing of 9 can be prevented. The same reference numerals as those in the embodiment shown in FIGS. 1 to 7 are used in the drawings.

It should be noted that the present invention is not limited to these embodiments and is naturally applied to other well-known structures and those obtained by appropriately combining these embodiments.

<Effect of the Invention> According to the elastic pivot of the present invention, since the rotary body connecting portion of the main body and the rotary body connecting portion are provided with radial displacement regulating stoppers that can come into contact with each other due to their radial relative displacement,
It is possible to prevent these displacements to be equal to or less than a predetermined value, prevent damage to the leaf springs, and obtain a highly reliable elastic pivot.

[Brief description of drawings]

FIG. 1 is a sectional view showing the internal structure of an embodiment of an elastic pivot according to the present invention, FIG. 2 is a right side view thereof, and FIG.
FIG. 4 to FIG. 7 are enlarged views of a main part in the drawings, FIG. 4 to FIG. 7 are manufacturing process drawings showing an example of the manufacturing method thereof, and FIG. 8 and FIG. Sectional views showing each, FIG. 10 is a conceptual view showing an example of use of the elastic pivot which is the object of the present invention, FIG. 11 is a perspective view showing an example of a conventional elastic pivot in a broken state, and FIG. 12 is its production. 13 is an exploded perspective view thereof, FIG. 13 is a sectional view thereof, and FIG. 14 is a left side view thereof. In the figure, 11 is an inner cylinder, 12 and 13 are outer cylinders, 14 and 15 are grooves,
16 is a groove portion, 17 is an annular groove, 18 and 19 are leaf springs, 23 is a protrusion, 24
Is an end plate, 25 is a flange pipe, α is the groove angle, S is a radial gap, and T is an axial gap.

Claims (1)

[Claims] 1. A cylindrical main body, one side of which is connected to a fixed body and the other side of which is connected to a rotating body with an annular groove formed on the outer peripheral surface as a boundary, and an inner peripheral surface of the main body in the axial direction. A pair of groove portions that are formed along the same and communicate with the annular groove; a semicircular arc-shaped first gap portion that is concentric with the main body and that opens to one end face side of the main body and the annular groove; and the first gap. A second semicircular arc-shaped gap opening concentrically with the main body in the opposite direction to the other end of the main body and the annular groove, and both ends are integrally connected to the inner peripheral surface of the main body. An elastic pivot having at least two leaf springs that intersect each other and a fixed body connecting part of the main body connected to the fixed body and a rotary body of the main body connected to the rotary body. The fixed body connecting portion is overlapped with the connecting portion with a certain gap therebetween. Elastic pivots, characterized in that a radial displacement restriction stopper which can abut on each other with the relative radial displacement of the rotating body connecting portion.