JPH02221728A - Vibrator holding structure - Google Patents

Abstract

PURPOSE:To make it possible to effectively utilize a holding structure for both frequency and phase modulators used with a piezoelectric ceramic vibrator by constituting the vibrator to be held by an elastic holding pin so as to make it not to touch on a holder. CONSTITUTION:The title holding structure consists of a bobbin-form holder 2 having a cylindrical part 5 in the intermediate part and upper and lower flange plate parts 7, 6 at both upper and lower ends, plural radial elastic holding pins 3 installed between the cylindrical part 5 and an inner circumferential surface 12 of a vibrator 1 and plural axial elastic holding pins 4 installed between these upper and lower flange plate parts 7, 6 of the holder 5 and upper and lower end faces 13, 14 of the vibrator 1, and this vibrator 1 is held by these elastic pins 3, 4 so as not to be touched to the holder 2. Accordingly, when it is applied to the holding structure of a piezoelectric ceramic vibrator, by way of example, any influence of this gentle holding structure to be given to a vibration characteristic of the piezoelectric ceramic vibrator is very little. Therefore the holding structure can be effectively utilized for both frequency and phase modulators used with this piezoelectric ceramic vibrator.

Description

DETAILED DESCRIPTION OF THE INVENTION (7) Technical Field The present invention relates to a vibrating body holding structure that holds a vibrating body that repeatedly expands and contracts without restraining its physical deformation.

Since the vibrating body that expands and contracts physically deforms, in order to maintain this, it is necessary to prevent free deformation as much as possible.

For example, a piezoelectric ceramic vibrating body falls under this category. A piezoelectric ceramic is formed into a hollow cylindrical shape, electrodes are attached to the outer and inner peripheries, and an alternating current voltage is applied between the electrodes. Since it is a piezoelectric element, the material deforms in proportion to the electric field.

Since electrodes are attached to the outer and inner peripheries, this piezoelectric ceramic expands and contracts in the radial direction. The frequency of expansion and contraction is
Equal to the frequency of the applied alternating voltage.

Further, the amplitude of expansion and contraction is proportional to the power of the applied alternating current voltage.

Such piezoelectric elements have several uses.

For example, by wrapping a single mode optical fiber around a cylinder, it is possible to change the phase of light propagating through the optical fiber. This is because when the piezoelectric ceramic vibrator expands and contracts in the radial direction, the optical path length and refractive index of the optical fiber change.

Moxibustion, phase modulation, and frequency modulation can be performed by wrapping a single-mode optical fiber wound around the sensor coil of an optical fiber gyro around the outer periphery of a piezoelectric ceramic vibrating body.

(a) Prior Art When a vibrating body whose shape changes in this way is fixed to a base plate, the conventional method is as follows. The underlying board will simply be referred to as the substrate.

(1) The bottom of the hollow cylinder is directly adhered to the substrate.

(11) The bottom surface of the hollow cylinder is glued to a sheet of flexible material such as silicone, rubber, or sponge, and the other surface of the flexible material is glued to the substrate. That is, a flexible material is interposed and fixed between the bottom surface and the substrate.

Of these, (i) is the simplest. The bottom surface is flat so it can be easily glued. In (11), b) a flexible material is interposed so as not to hinder the expansion and contraction of the vibrating body.

(1) Problems to be Solved by the Invention As mentioned above, the fixing method of bonding the piezoelectric ceramic vibrating body to the substrate at the bottom surface has the following problems.

Since both bottom surfaces are fixed to the substrate, the circumferential surface cannot expand or contract freely. For this reason,
When an AC voltage is applied to a piezoelectric ceramic vibrator, the vibration characteristics in a free state cannot be reproduced. In other words, even if a voltage of the same amplitude is applied, the amplitude of expansion and contraction is larger in the free state than in the restrained state. Moreover, the natural frequencies are also different.

When a flexible material is used, the state becomes closer to a free state. However, free deformation is still hindered. Even if voltage and vibration characteristics are measured in a free state, the same characteristics cannot be obtained if the device is restrained.

If the piezoelectric ceramic vibrating body is used as a frequency modulator, the degree of frequency modulation will change before and after bonding. This is a problem in terms of guaranteeing the performance of the modulator.

B) Structure In the present invention, the inner peripheral surface and upper and lower end surfaces of the cylindrical vibrating body are held by a plurality of holding bottles that can be elastically deformed.

The holding bottle has a bobbin shape, and is attached to a holding tool ζ passed through the inside of the vibrating body. The holder and the vibrating body are not in direct contact. Since a plurality of elastic holding bottles are interposed between the two, the vibrating body can expand and contract as freely as possible.

The elastic holding bottle can be made of a solid elastic material such as rubber, or it can be made of a metal elastic material such as a helical spring.

The vibrating body is held so that its axial direction faces the vertical direction.

Therefore, even if the vibrating body expands or contracts in the radial direction, the position of the center of gravity does not change. In other words, the weight of the vibrating body acts as an inertial force,
It does not interfere with the expansion and contraction movement.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below with reference to drawings showing examples of the present invention.

FIG. 1 is an overall perspective view, and FIG. 2 is a central vertical sectional view. FIG. 3 is a sectional view taken along the line ■-■ in FIG. 2.

This holding structure is for holding the cylindrical vibrating body 1 loosely. Therefore, the bobbin-shaped holder 2
and a plurality of elastic holding bottles 3.4 attached to the holding device 2.

The vibrating body 1 has a cylindrical shape, and has a cylindrical outer peripheral surface 11 and an inner peripheral surface 1.
2, and upper and lower end surfaces 13.14.

For example, in the case of a piezoelectric ceramic vibrating body, electrodes are formed on the outer peripheral surface and the inner peripheral surface, and lead wires are connected to the electrodes. When used as a frequency modulator for an optical fiber gyro, a single mode optical fiber is wound around the outer peripheral surface.

However, for the sake of simplicity, the vibrating body 1 is shown here as a simple cylinder without illustrations of electrodes, lead wires, and the like.

The holder 2 has a bobbin shape, and has a cylindrical portion 5 in the middle, a collar plate portion 6 at the bottom, and a collar plate portion 7 at the top.

The collar plate portion 6.7 and the columnar portion 5 can be separated at any suitable location.

The outer diameter of the collar plate is wider than the inner diameter of the vibrating body. The inner diameter of the vibrating body is wider than the outer diameter of the cylindrical portion 5.

The holder consisting of the collar plate part 6.7 and the columnar part 5 is cut off at an appropriate location, the vibrating body 1 is inserted into the columnar part 5, and the collar plate part 6.7 is removed again.
7. Join the cylindrical part 5.

This prevents the vibrating body 1 from coming off the holder 2.

A plurality of radial elastic holding bottles 3 protrude radially Fζ from the cylindrical portion 5 of the holding tool 20.

The tip of the radial elastic holding bottle 3 is connected to the inner circumferential surface 1 of the vibrating body 1.
It is in contact with 2. The vibrating body 1 is held movably in the radial direction by the cooperative action of the plurality of radially elastic holding bins 3.

The radially elastic retaining bottle 3 can be made of a flexible material such as rubber. In this case, as shown in the figure, the portion that contacts the vibrating internal circumferential surface 12 is a thin pointed tip 9.

This is to narrow the contact area and make it easier for the vibrating body to displace. The other reason is to reduce the cross-sectional quadratic coefficient of the radial elasticity holding bottle 3 with the pointed tip 9 to make it easier to bend.

The radial elasticity holding bottle 3 is attached to the cylindrical portion 5 at its base (inner end).

However, the peak 9 may or may not be bonded to the inner circumferential surface 12 of the vibrating body 1.

If the radially elastic retaining bottle 3 is always compressed, the point 9 will press against the inner circumferential surface 12, so there is no need for bonding.

However, if, on the contrary, the radially elastic retaining pin 3 is constantly under tension, the point 9 must be glued to the inner circumferential surface 12.

Further, the radial elastic holding bottle 3 can be made of a metal elastic body such as a helical spring. In this case, some kind of hook is attached to the inner circumferential surface 12 of the vibrating body and the cylindrical portion 5 of the holder 2, and the end of the helical spring is hooked onto the hook.

When using helical springs, they exert a tensile force on each other.

The force exerted on the vibrating body 1 by the elastic holding bottle 3 only needs to be an elastic force, and may be either a tensile force or a compressive force. This is because the resultant forces cancel each other out and an equilibrium position can be maintained.

There must be at least three radially elastic retaining bins so that the resultant forces cancel each other out. In this example, there are six elastic holding bottles, three on the top and three on the bottom.

Both form a central angle of 120°, and the positions of the elastic holding bins are the same on the upper and lower sides.

However, this is just an example. The upper and lower elastic holding bottles may have a twisted positional relationship.

Furthermore, there may be four or more elastic holding bottles in one plane.

Furthermore, the number of pairs is not limited to two, upper and lower, but may be three or more.

Furthermore, axially elastic holding pins 4 are provided on the lower collar plate part 6 and the upper collar plate part 7 of the holder 2 in an upward and downward direction.

These elastic holding bottles 4 are in contact with the upper end surface 13 and lower end surface 14 of the vibrating body 1. The vibrating body can be slightly displaced in the vertical direction.

The axially elastic holding bottle 4 is made of a flexible elastic material. It may also be a solid elastic body such as rubber. In this case, in order to make it easier to bend, it is preferable to make the contact portion with the vibrating body a narrow tip 10.

The axially elastic body holding bottle 4 can also be constructed of a metal elastic body such as a helical spring. In this case, the end face 1 of the vibrating body
3.14. Attach hooks to the upper and lower collar plates 7.6 of the holder 2 to hang the helical spring.

In this example, there are three axial elastic holding pins on the top and bottom, but any number may be three or more, and may be 4, 5, 6, . . . .

Further, it is not necessary that the axial elastic holding pins are aligned on the upper and lower sides. It may be in a twisted position.

A female screw hole 8 is bored in the center of the lower surface of the holder 2. This is a female thread for attaching the holder to some substrate (not shown).

(4) Function The holding structure of the present invention elastically supports the inner end surface and end surface of the vibrating body using elastic holding bottles. Further, the vibrating body is placed so that its axial direction is vertical.

The restraining force on the vibrating body becomes extremely small.

If the vibrating body is a piezoelectric ceramic vibrating body, the influence on the vibration characteristics of the piezoelectric ceramic vibrating body when voltage is applied can be minimized.

I will explain in more detail.

Assume that the vibrating body expands and contracts in the radial direction. Since the vibrating body is provided vertically, the position of the center of gravity does not change due to expansion and contraction. Therefore, the weight of the vibrating body does not act as an inertial force and impede the movement of the vibrating body.

When the vibrating body expands and contracts in the radial direction, the axially elastic holding bottle 4
bends inward and outward. However, this is easy because the pins are bent rather than stretched. The axial elastic holding bottle 4 does not interfere with the expansion and contraction movement.

Resistance to the expansion and contraction movements is provided by the radially elastic retaining pin 3. However, this does not support the own weight of the vibrating body 1, but only adjusts its position in the radial direction. Therefore, a bottle rich in elasticity νζ can be used. In other words, thin rubber materials, thin helical springs, etc. can be used.

(b) Effects According to the present invention, the vibrating body can be held loosely by the elastic holding pin.

The present invention can be used, for example, as a holding structure for a piezoelectric ceramic vibrating body.

In this case, the gentle holding structure has little influence on the vibration characteristics of the piezoelectric ceramic vibrator. Standing vertically, the present invention,
It is extremely effective if used as a holding structure for frequency modulators and phase modulators using piezoelectric ceramic vibrators.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of the vibrating body holding structure of the present invention. Figure 2 is a central vertical sectional view. FIG. 3 is a sectional view taken along the line ■-■ in FIG. 1... Vibrating body 2...Holder 3... Radial elastic holding bottle 4...Axial elastic holding bottle 5...Cylindrical part 6...Lower flange plate part 7... Upper flange plate part 8...Female screw hole 9.10... Point 11...Outer peripheral surface 12...Inner peripheral surface 13...Top end surface 14...Lower end surface inventor Mountain Field Health

Claims (1)

[Claims] A bobbin-shaped holder 2 having a cylindrical part 5 in the middle, an upper flange plate part 7 and a lower flange plate part 6 at the upper and lower ends, and between the cylindrical part 5 of the holder 2 and the inner circumferential surface 12 of the vibrating body 1. A plurality of radial elastic holding pins 3 provided, and a plurality of axial elastic holding pins 4 provided between the upper and lower collar plates 7, 6 of the holder 2 and the upper and lower end surfaces 13, 14 of the vibrating body 1. , the vibrating body 1 is the holder 2
A vibrating body holding structure characterized in that the vibrating body is held by elastic holding pins 3 and 4 so as not to come into contact with the vibrating body.