JPH02151845A - Vibration proof supporting device for photographing device - Google Patents

Abstract

PURPOSE:To reduce the size and weight of a photographing device and to prevent deterioration in a photographing plane by supporting a barrel so that it is balanced in a space by a specific spring mechanism in floating fashion. CONSTITUTION:Formula I indicates distances between a barrel gravity position and connecting points to four springs 4-1 to 4-4 in a stator 3 and to the barrel 1 when the barrel 1 is positioned in the center of the space enclosed by the stator 3. In the formula I, l1 and l2 are distances between the plural connection points to the springs 4-1 to 4-4 in the stator 3 and to the barrel and the barrel gravity position, and r1 and r2 are distances in a direction perpendicular to a photographing optical axis. Consequently, the barrel can be supported in a vibration proof condition where the image blur of a photographing device is prevented, and a small-sized, lightweight vibration-proof mechanism is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application) The present invention supports a lens barrel floatingly in space using a spring mechanism, so that it can be supported even when a fixed body supporting it vibrates. The present invention relates to a photographing device having a mechanical anti-vibration mechanism that minimizes the vibration of a lens barrel, and in particular to a small and lightweight anti-vibration support device that can be suitably applied as an anti-vibration device for a portable video camera, etc. It is something.

(Prior art) Conventionally, the anti-vibration mechanism for photographic equipment uses the gyro effect of a gyro that rotates at high speed, or supports the surface plate with air pressure or hydraulic pressure to prevent vibration between the photographic equipment and the surface plate. Some devices are known that are designed to attenuate vibrations by forming an air layer or oil layer with very weak spring properties.When taking pictures that require vibration isolation, the shooting optical system of a video camera, etc. is mounted inside the camera body. It is possible to support the camera body in a manner that can dampen such vibrations, or to detect vibrations occurring in the camera body and actively vibrate the photographic optical system in the opposite direction based on the detected vibrations to prevent image distortion. It is being done.

(Problems to be Solved by the Invention) However, with the above-mentioned vibration isolation mechanism, the device is large and heavy, and, for example, in a system in which the imaging device is fixed to the vibration isolation mechanism, it is difficult to move the imaging device. The problem is that it lacks sex.

Additionally, cameras that detect vibrations generated in the camera body and actively move the photographing optical system in the opposite direction based on the detected vibrations, although they do have the effect of preventing image blur, The system constituting the image forming apparatus tends to be complicated and expensive, and further improvements are required in order to provide such an image prevention mechanism at a low cost and to make it widely available in video cameras and the like.

Therefore, the inventor of the present invention solved the above-mentioned problems by creating a device with a relatively simple mechanical mechanism, light weight, and excellent mobility by making it lightweight and compact, making it easy to carry. The present invention has been made for the purpose of providing a photographing device.

That is, an object of the present invention is to provide a novel device with an anti-vibration function that can support a photographing device in an anti-vibration state that prevents image blurring using a mechanical spring mechanism.

Another object of the present invention is to provide an anti-vibration support device for a photographing apparatus that can be used hand-held by a photographer by providing a small and lightweight anti-vibration mechanism.

(Means for Solving the Problems) Therefore, the features of the vibration-proof support device for a photographing device according to the present invention, which has been made to achieve the above object, include the photographic optical system and the rear side of the photographic optical axis. A lens barrel integrally equipped with an imaging means is stretched by a fixed body that surrounds the outer periphery of the lens barrel in a plane perpendicular to the imaging optical axis, and four spring members with the same spring force and the same spring constant are stretched as a set. An anti-vibration support device floatingly supported via a spring mechanism, in which two of the four spring members are arranged on one of two mutually orthogonal planes including the photographing optical axis. These two spring members are connected to the lens barrel on the rear side of the photographing optical axis and to a fixed body on the front side of the photographing optical axis, and the above four spring members are connected on the other of the two orthogonal planes. The remaining two books are arranged, and these two spring members are connected to the lens barrel on the front side of the photographing optical axis and to the fixed body on the rear side of the photographing optical axis, and on each of these planes. By arranging the two springs in a positional relationship that intersects the photographing optical axis with the line of symmetry, a set of four springs is constructed, and the lens barrel is positioned at the center of the space surrounded by the fixed body. The distance between the connection points of these four springs to the fixed body and the lens barrel and the center of gravity of the lens barrel when the lens is moved is set to the relationship expressed by the following formula (2).

ILl ・f12=-'-rl ・r2 − ・ ・
■[However, JZ, f12 is the distance in the shooting optical axis direction between each connection point to the fixed body of the spring and the lens barrel and the center of gravity of the lens barrel, and rl and r2 are the distances perpendicular to the shooting optical axis direction. The distance in the direction. Ko.

The reason why the above configuration is adopted in the present invention is as follows.

In other words, when a lens barrel having a photographic optical system is floatingly supported in space, a fixed body that supports the floating lens barrel (typically a camera body supported by a photographer; hereinafter referred to as the camera body) moves or In order to prevent blurring of the photographed image due to this movement or rotation when rotating, it is simply possible to keep the lens barrel spatially fixed, but in reality, the lens barrel may deteriorate the photographed image. If we break down the relationship between one rotation of the barrel movement and one rotation of movement that is likely to occur in the camera body, we can see that, for example, when considering the usage situation of a video camera, etc., the fact that the camera body moves in the direction of the photographing optical axis is not realistic. There is no problem even if it hardly occurs, and if the camera body were to move in the direction of the shooting optical axis, it would be better to move the camera body rather than spatially fixing the lens barrel regardless of this movement. It is preferable to follow the movement of. This can be considered similarly when rolling (rotation around the photographing optical axis) occurs in the camera body, and it is appropriate for the lens barrel to follow the rolling of the camera body.

However, if the camera body experiences yawing (rotation around the vertical axis when the optical axis is horizontal) or pitching (rotation around the horizontal axis perpendicular to the optical axis), the lens barrel It is undesirable to follow the rotation of the camera body as this will obviously lead to image blurring, and it is desirable for the lens barrel to remain spatially fixed as the camera body rotates. .

Further, movement or rotation of the camera body that causes the lens barrel to move in a direction different from the same movement or rotation causes image blur, and must be suppressed as much as possible.

If we consider the external force that acts on the camera body of a video camera, etc. as described above, and the movement and rotation of the lens barrel that is in a spatially floating state that should be restrained, we can formulate the following relationship. It is thought that it is necessary for the anti-vibration support device of the photographing device that is the subject of the present invention to satisfy the following.

That is, assuming that the photographing optical axis of the lens barrel is the X-axis, the horizontal direction perpendicular to the X-axis is the y-axis, and the vertical direction is the Z-axis, then (1) the camera body is, for example, x, y.

When each shift is made in the z-axis direction, the lens barrel follows and moves in this shift direction, but when moving in a direction different from the shift direction or rotating around the X, Y, and Z axes, the lens barrel spatially moves. ■When the camera body rotates (rolls) around the X-axis, the lens barrel follows this rolling and rotates, but in a direction different from the rotation. rotation to x, y,
Regarding movement in the z-axis direction, the lens barrel must remain substantially fixed in space, and the camera body must not rotate (yawing or pitching) around the y- and z-axes.
When this occurs, the lens barrel will not follow the yawing or pitching of
■ The lens barrel remains substantially fixed spatially even when moving in the y- and z-axis directions.
It is necessary to satisfy the following relationship.

The present inventor has developed a vibration isolation support device using the above spring member as a mechanical mechanism that can satisfy the above relationship.

The spring mechanism in the present invention is constituted by four springs and one set of springs, and it is also possible to use two or more sets of spring mechanisms as long as they do not cause problems such as mutual interference.

As mentioned above, each set of four spring members is the same (initial spring force F when tensioned on the device).
, and spring constant k are the same), and the spatial arrangement relationship described above must be satisfied.

Known optical systems and imaging means mounted on the lens barrel can be used, and the latter imaging means is a so-called C
A solid-state image sensor such as a CD (charge coupled device) is preferably used.

The above-mentioned lens barrel is floatingly supported by a spring member on a fixed body such as a camera body, but this kind of support is for the purpose of preventing image blurring during imaging, so it is not supported at other times. There is no need for a floating support state of the lens barrel. Therefore, in addition to floating support using a spring mechanism, when configuring an actual photographic device, it is necessary to provide a fixing means that can connect the lens barrel in a fixed relationship with a fixed body such as a camera body at a suitable time. Appropriate. Such fixing means may be mechanical or electromagnetically driven.

(Function) By having the above-described structure, the anti-vibration support device of the present invention supports the lens barrel in a floating manner in space, and can also capture images caused by yawing or pitching that occur during shooting with a photographing device such as a video camera. It is possible to suppress blurring.

(Example) The present invention will be described below based on embodiments shown in the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a lens barrel section, in which a plurality of lens groups (not shown) and an imaging means 2 (for example, a CCD) are integrally attached, and the reflected light from the subject is condensed onto the imaging means 2. The image is converted into an electrical signal, which is sequentially read out by a video signal processing circuit to create a video signal. Conventionally known internal structures, optical and electrical circuit configurations of such a lens barrel can be used.

The feature of this example is that the lens barrel 1 is floatingly supported in a vibration-proof manner using a set of four spring members as described below.

That is, the lens barrel section 1 is attached to a fixed exterior (such as a camera body).
For convenience of explanation, only the inner wall surface of the fixed body is shown in the figure) 3, the tension adjustment mechanism 5152, 53. It is characterized in that it is held at the same spatial extension length via 54. The tension adjustment mechanism is shown in FIG. 1(e), for example, and is for adjusting these initial spring forces. The four springs form a radial shape at 90° intervals in the circumferential direction when viewed from the front view direction (photographing optical axis direction) shown in FIG. When viewed from each direction of two axes orthogonal to each other in a plane perpendicular to the optical axis, the two springs are arranged in the shape of a raccoon hook, and therefore,
In this example, these four springs are arranged in two orthogonal planes including the photographing optical axis 50 (in other words, in FIG. Two springs are placed on each side, and two springs are placed on one plane. ．． 44 extends from the rear end side of the lens barrel 1 (the left side in FIG. 1(b)) to the front end side of the fixed exterior 3 (the first
On the other plane, two springs 42 and 43 are fixed from the front end side of the lens barrel 1 (on the right side in Fig. 1(b)). Rear end side of exterior 3 (first
It is stretched across each connection point (on the left side of Figure (b)).

The two springs on each plane are connected to the photographing optical axis 5.
They are arranged symmetrically so as to form a relationship with 0 as the line of symmetry.

Furthermore, as explained in FIGS. 2(a) and 2(b), these four springs have their tension dimensions viewed from the center of gravity G of the lens barrel in the direction of the photographing optical axis and in a direction perpendicular thereto. Each dimension r1 when divided. r2. and x, , i2 (each added in FIG. 2) are set to have the relationship of the above equation 0.

With such a configuration, the lens barrel 1 of this example prevents the lens barrel 1 from degrading captured images even if an external force is applied to the fixed housing 3 from the outside to cause it to move in parallel or rotate. The initial objective of no movement is realized.

That is, if we break down the external forces acting on the fixed exterior 3 and explain the movement of the lens barrel 1 supported by the configuration of this example when these forces act, it will be as follows.

a: When a moving force acts on the fixed sheath 3 in the direction of the photographing optical axis and causes it to move in the same direction, the lens barrel 1 follows the movement of the fixed sheath 3 due to the large spring constant of each spring and moves toward the same photographic optical axis. However, in other directions, the spring forces are balanced and no movement or rotation occurs, or even if it occurs, the movement is minute.

b. When a moving force in the vertical direction acts on the fixed sheath 3 and a force is generated in the same direction, the lens barrel 1 follows the movement of the fixed sheath 3 and moves in the same vertical direction due to the large spring constant of each spring. However, in other directions, the spring forces are balanced and no movement or rotation occurs, or even if it occurs, the movement is minute.

8 forces in the horizontal and lateral directions act on the fixed exterior 3, and the
When a force is generated, the lens barrel 1 follows the movement of the fixed exterior 3 due to the large spring constant of each spring and moves in the same horizontal and lateral direction, or in other directions, the spring forces are balanced and the lens barrel 1 moves or moves. No rotation occurs, or even if it does occur, it is a very small amount of movement.

When a rolling force acts on the fixed sheath 3 and causes it to rotate in the same direction, the lens barrel 1 follows the rolling of the fixed sheath 3 due to the large spring constant of each spring, but in other directions, the spring force are balanced and no movement or rotation occurs, or even if it does occur, it is a minute amount of movement.

e: When a yawing force acts on the fixed sheath 3 and causes rotation in the same direction, the lens barrel 1 does not follow the fixed sheath 3 because the spring forces are balanced in the yawing direction, and also in other directions. Similarly, the spring forces are balanced so that no movement or rotation occurs, or even if it occurs, the movement is minute. Therefore, the lens barrel 1 is spatially substantially fixed against the yawing of the fixed sheath 3.

f: When a pitching force acts on the fixed sheath 3 and causes rotation in the same direction, the lens barrel 1 has a balanced spring force in the pitching direction and does not follow the fixed sheath, and the same goes for other directions. The spring forces are balanced and no movement or rotation occurs, or even if it does occur, it is a minute amount of movement. Therefore, the lens barrel 1 is spatially substantially fixed against pitching of the fixed sheath 3.

Below, the relationship between the movement of the fixed exterior 3 and the lens barrel 1 is as follows:
What is achieved by the configuration of the embodiment of the present invention described above will be explained in detail with reference to the drawings.

FIG. 2 shows the spring and tension adjustment mechanism in the mechanism shown in FIG. 1 in an abstract manner for ease of explanation, with spring 41 and tension adjustment mechanism 5. Hereinafter, the entire spring 42 and the tension adjustment mechanism 52 will be referred to as the spring 42, the spring 43 and the tension adjustment mechanism 53 will be referred to as the spring 43, and the spring 44 and the tension adjustment mechanism 54 will be referred to as the spring 44.

Here, as shown in FIG. 2, four springs 41 to 4
4 to the lens barrel 1, the radius is rl, and for mounting to the fixed exterior 3, the radius is r2, and the horizontal distance from the center of gravity G of the lens barrel 1 to the spring mounting position is relative to the lens barrel 1. is fl, 1,
2 for fixed exterior 3 (see Figure 2 (b))
.

In addition, let the angle between the direction of the optical axis 50 and the spring 41 (the same applies to other springs) be β (hereinafter referred to as the plane angle), as shown in Fig. 2 (e
), and the angle between the spring and the horizontal surface 60 (7) is α (hereinafter referred to as spring angle) (see FIG. 2(f)). Note that since the spring length of the hypotenuse of the triangle in FIG. 2(f) represents the actual length, this diagram will hereinafter be referred to as an actual length diagram.

Now, in FIG. 2, considering the weight of the lens barrel 1 as a photo, it is supported so that the center position of the circular fixed exterior becomes the photographing optical axis 50, and each of the four springs 41 to 44 is This figure shows a state in which the spring force and spring constant are the same, and the tension lengths are the same. In the following description, it is assumed that the spring can easily change its posture with respect to the movements of the lens barrel and fixed exterior, and that the frictional resistance of the spring mounting portion is sufficiently small to the extent that it can be ignored.

From the state shown in Fig. 2, since the own weight of the lens barrel 1 actually acts on this mechanism, Fig. 3 shows a state in which the lens barrel 1 is assumed to be displaced vertically downward due to this own weight. It is shown in

In Fig. 3, W(□f) is the own weight of the lens barrel 1, -S,
When is the vertical downward displacement of the lens barrel, the above plane angle β does not change because the attachment of the spring to the lens barrel 1 only shifts the position downward; on the other hand, the spring angle α is α+Δ
It can be considered that it changes to α, ·Sw. Note that the elongation of the spring is ΔX, ·Sw. However, here, Δα is expressed by the following formula (■), and ΔXs is expressed by the following formula (■). Also, the symbol 50° indicates the photographing optical axis at the displaced position.
There is.

[However, in the above formula, the subscript ■ indicates a displacement component in the vertical direction, and the subscript S indicates a displacement component due to a shift. The above relationships can be similarly determined for the other springs 42, 43, and 44, and by arranging them, the following Table 1 can be obtained.

Table 1 Next, consider the balance between the force acting on the lens barrel and the moment around the center of gravity under the condition that each spring changes as described above.

First, the balance of forces in the vertical direction is expressed as T (hereinafter referred to as balance tension T):
If the spring constant is k, the angular displacement in Fig. 3(f) is minute, so geometrically SinΔα, S, and ΔαV'S
W, COSΔαVSwLi1, and since the vertical force due to the spring and the lens barrel's own weight are balanced, it can be expressed as 4(T・ΔC1!vCOSC1+×5lnQ・SW−WTgf) = 0, and therefore, It can be seen that the amount of deflection S1 due to its own weight is given by the following formula (■).

Next, considering the balance of forces in the optical axis direction and the horizontal direction, the forces in these directions are balanced as is clear from FIG. 2 and Table 1 above.

From the balance of these forces, it can be seen that the lens barrel causes vertical downward displacement due to its own weight, but the balance in the horizontal direction and the optical axis direction is maintained.

Next, considering the rotational moments in the three directions that act on the lens barrel due to the displacement in the vertical direction, first, the moments in the pitching direction are kept balanced, as is clear from FIG. 3(b).

As for the moment in the rolling direction, since the left and right opposing springs apply the same spring force in opposite directions to the center of gravity G, the balance condition is clearly satisfied.

Finally, considering the moment in the yawing direction, the sum of the moments in the yawing direction is expressed by the following equation (2) from the change in the spring force of each spring.

If the mechanism of this example were to generate yawing due to its own weight, this would result in deterioration of the photographed image and would be inappropriate, so the above formula (■) should be zero (the sum of the moments in the yawing direction is zero). Therefore, satisfying the above formula % is a condition for not causing image deterioration in the mechanism of this example.

Here, by substituting the equation (■) showing the relationship between the deflection Sw given from Fig. 2 (e) and (f) into the above equation (〇), we find that the balance tension T1 is 1 and the spring constant is 1, and each spring is rl indicating the tensioning dimension, T2.111. T
The following equation (■), which is a relational expression of 12, is obtained, and in the end, this equation becomes
This is nothing but a condition for preventing yawing from occurring when the lens barrel 1 and the fixed exterior 3 are displaced relative to each other in the vertical direction.

T= k・(i++f12)2+ (T2−rl)2・
- A relationship of 0 or more indicates a condition for not causing yawing when the fixed sheath 3 and the lens barrel 1 are vertically displaced relative to each other, but pitching may occur due to horizontal and lateral relative displacement. The condition where no is present is given in exactly the same way.

If the above formula (■) is combined with the above-mentioned self-weight W Izf+, then 5W=W(rfl /4k ・ ・
・(1)' is obtained. This is because the equivalent spring constant in the displacement direction of the spring acting on lens barrel 1 is 4 in order to prevent yawing from occurring due to vertical displacement (or pitching from horizontal lateral displacement). It can be said that it shows.

As described above, by setting the balance tension T of the four springs and the spring constant k so as to satisfy the above formula ), the photographing optical axis 50 of the lens barrel 1 is at the reference numeral 5 in Fig. 3.
Apart from the 8 parallel movements to the position indicated by 0°, no tilting or the like occurs, and a relationship is satisfied in which undesirable movement of the lens barrel that would lead to deterioration of the captured image is suppressed.

The anti-vibration support device of this example not only satisfies the above relationship, but also needs to satisfy a relationship that does not cause image deterioration in response to various relative displacements between the lens barrel 1 and the fixed exterior 3. There are several cases (I) to (V), and these will be explained in order below.

(I) When the fixed sheath 3 is rotated by θp in the pitching direction FIG. 4 shows the changes in each spring that occur when the fixed sheath 3 is rotated by θp in the pitching direction, and FIG. 4(e),
(f) shows changes in the spring 41.

The amount of change in the spring angle α is +Δαp ・θp, and θp is s
Assuming that inθp is a small angle between inθp and θp (this assumption is valid in view of the actual vibration to be damped), the second-order minute term can be ignored, and Δαp is given by the following equation.

The amount of change in the plane angle β is Δβp·θp. However, Δβ
p is based on the following formula.

The above relationships are similarly determined for the other springs 42, 43, and 44, and Table 2 below is obtained by arranging them.

Table 2 (1-1) Also, the elongation of the spring is Δxr·θp. Considering the balance of the force and moment acting on the lens barrel in a state where the above spring is displaced, first, the sum of the forces in the vertical direction is expressed by the following equation (1-4), and Δxr is expressed by the following equation.

is given by

4 (TΔyvcosy+kI!Ixssjn fell) 5.
-w (gfl H+ H(1-4) and the above formula ■
Substituting , we get 7, which shows that the vertical forces are balanced as a whole.

The sum of forces in the optical axis direction is given by the following equation (1-5).

4 [(Tsinci: Δxscos cut to Δo+v−)s
inβΔβp−(Tcos+xΔ戊I and Δxssin
ci:) cosβΔ&p”kΔx, 5inycosβ
ΔxvlswθP...(1-5) Substituting the above equations ■ and ■ into equation (1-5) and sorting it out, we get 4k(Δx, sin Δx, -ΔxP)COSβ・S,
-θp -・ (1-6) is obtained, but SW and θ2 are minute amounts, and their influence on image deterioration is small enough to cause no practical problems, so this can be virtually ignored. There is no problem.

The sum of horizontal forces is given by the following equation (1-7).

4 [T (coso:cosβΔβP-sin13s
inyΔdirectionP)−Δx, cosci+sinβ]OP
When formula (1) is substituted into formula (1, -7) and rearranged, the sum becomes zero, and it can therefore be seen that the horizontal forces are balanced.

Next, consider the rotation of the lens barrel 1.

First, the sum of moments in the pitching direction is expressed by the following formula (1-8)
is given by

+cos73sinmΔαP) Δx, cosyco
sβ ) θP ・ ・ ・ (1-8) Here, the sum of the moments on the levers is: 1 is the condition for spatially stationary and vibration-proofing state to be maintained, so if the above equation is rearranged with zero, the following equation (2) is obtained.

This equation (■) is a relational expression between the balance tension T and the spring constant like the above equation (■), and by substituting the equation (■) into the equation (■), and from Fig. 2 (f), this equation (1-10) can be transformed into the equation (2) Since it is zero, it can be seen that even if the fixed exterior is tilted in the pitching direction, yawing does not occur in the lens barrel.

Finally, the sum of moments in the rolling direction acting on the lens barrel is given by the following equation (1-11).

By substituting these into the formula ■ and rearranging it, we get fll・k
2-1/2・rl・r2...■ is obtained.

This equation (■) is a condition that does not cause yawing in the lens barrel when the fixed exterior 3 rotates in the yawing direction, which will be described later.It also represents the condition that does not cause image deterioration due to the spring mechanism of this example given by the above equation (■). Since it includes this, it can be said that the condition for tensioning the spring in order to realize the object of the present invention in the spring mechanism of this example is violated.

The sum of moments in the yawing direction acting on the lens barrel is given by the following equation (1-10).

kΔxssinci:)sinβAy,+Δx,si
n-sinβΔalternativev]SJp・・・(1-11) Substituting the formula (■) into this and rearranging it, we get・・・・(1-121).

The sum of this equation (1-12) is not τ, but sW and θ
, is a very small amount, and its influence on image deterioration is so small as to cause no practical problems, so it can be virtually ignored.

(11) When the fixed sheath 3 rotates θy in the yawing direction FIG. 5 shows the changes in each spring that occur when the fixed sheath 3 rotates Oy in the yawing direction, and FIG. 5(e),
(f) shows changes in the spring 41.

The amount of change in the spring angle α is +Δαy・θy, and θy is si
Assuming that it is an infinitesimal angle of nθy4θy (this assumption is valid in view of the actual vibration to be damped), the second-order infinitesimal term can be ignored, and Δαy is given by the following equation.

・ ・ ・ (2-1) Also, the elongation of the spring is Δxr·θy (see (1-2) above for Δ×r).

Further, the amount of change in the plane angle β is Δβy·θy. However, △
βy is based on the following formula.

The above relationships can be found in the same way for the other springs 42, 43, and 44, and by rearranging them, the following equation 3 can be obtained.

Table 3 Considering the balance of forces and moments acting on the lens barrel with the above spring displacements, first, the sum of vertical forces can be calculated using the following formula (2-3) % Formula % This is combined with the above formula ■ Substituting , we get ;, which shows that the vertical forces are balanced as a whole.

The forces in the optical axis direction and the horizontal direction are clearly balanced as can be seen from FIG. 5(C).

Next, consider the rotation that acts on the lens barrel.

The moments in the pitching direction are clearly balanced, as seen in Figure 5(b), and the moments in the rolling direction acting on the lens barrel also meet the balancing conditions, as seen in Figure 5(a). Is pleased.

The sum of moments in the yawing direction acting on the lens barrel is given by the following equation (2-4).

4T (L (coscycosβΔβ, -5inf3
sinI11! Δ01! , )...
This formula becomes zero.

In other words, satisfying the formula (2) explained in (I) above means that when rotation in the pitching or yawing direction acts on the fixed exterior 3, the lens barrel does not follow in these directions and the lens barrel spatially moves. It is understood from the above explanations of (1) and (I+) that the condition is to maintain a stationary state and not cause any undesirable movement of the lens barrel that would lead to image deterioration.

Next, the force and moment that act on the lens barrel when the fixed exterior 3 is shifted in the optical axis direction, horizontally and laterally, and rotated in the rolling direction will be explained.

(Ill) When the fixed exterior 3 is sy-displaced forward in the optical axis direction. FIG. 6 shows the changes in each spring that occur when the fixed exterior 3 is sy-displaced in the optical axis direction. f
) illustrates changes in the spring 41.

The amount of change in the spring angle α is −Δαf −sy, and Δαf
is expressed by the following equation (3-1).

The elongation of the spring is Δxf-sy. However, Δxf is given by the following equation.

The amount of change in the plane angle β is −Δβf −sy, and Δβf is expressed by the following formula.

r2-rl The above relationship is similarly determined for the other springs 42, 43, and 44, and Table 4 below is obtained by arranging this.

Table 4 4(T (cosots inβΔβf+CO3βs
in cutting Δotr) + ΔXrCOS[XCO5β )s
r...(3-5) Substituting the above equation (■) into equation (3-5) and rearranging.The balance of the force and moment acting on the lens barrel when the spring is displaced more than that is as follows. Considering this, first, the sum of the forces in the vertical direction is expressed by the following formula (3-4)%Formula %This formula (3-4) is based on the formula (2), so it can be seen that the vertical forces are balanced as a whole.

The sum of the forces in the optical axis direction is given by the following formula (:]-5)...
・(3-6) It can be seen that the spring constant in the optical axis direction is larger than 4. Therefore, this large spring constant causes the lens barrel 1 to move to follow the shift of the fixed sheath 3 in the optical axis direction.

The sum of horizontal and lateral forces is given by the following equation (3-7), and is 4((
Tcos 侃Δo(y−toΔxssir++x)Δyf−
ΔxfsinyAyv)sinβ5w5f (3-7) When the above formula (■) is substituted into this formula (3-7), the following formula (3
-8) is obtained.

4k(ΔCMf−muxfsin(xΔci:v)sin
β・s,・s, ・・−・(3-8) This formula (3−
Although the value of 8) is not a stem, it is a second-order minute amount of Sw and Sf, so the movement of the lens barrel in the horizontal direction can be ignored.

Next, consider the rotation of the lens barrel.

The sum of moments in the pitching direction acting on the lens barrel is given by the following equation (3-9).

(3-11) Substituting the above formula (■) into this formula (3-11), it becomes zero, so even if the fixed sheath 3 shifts in the optical axis direction, no yawing occurs in the lens barrel 1. I understand.

The sum of moments in the rolling direction acting on the lens barrel is given by the following equation (3-12).

kAXrSin (1!ΔQ4vC
OSβ) ]55wSr (3-9) By substituting the above formula (3) into this formula (3-9) and rearranging it, the following formula (3-10) is obtained.

5v IS.

...(3-10) Although the value of this equation (3-10) is not zero, it is a second-order infinitesimal amount of Sw and Sf, so the movement of the lens barrel in the pitching direction can be ignored.

The sum of moments in the yawing direction acting on the lens barrel is given by the following equation (3-11).

...(3-12) Although the value of this equation (3-12) is not zero, since it is a minute amount of Sf, the movement of the lens barrel in the rolling direction can be ignored.

Even if the exterior and lens barrel are displaced relative to each other in the optical axis direction due to the above,
The lens barrel does not undergo any undesirable movement that would degrade the photographed image.

(IV) When the fixed sheath 3 is displaced sh in the horizontal and lateral direction FIG. 7 shows the changes in each spring that occur when the fixed sheath 3 is displaced sh in the optical axis direction, and FIGS.
) illustrates changes in the spring 41.

The amount of change in the spring angle α is −Δαh−sh, and Δαh is expressed by the following equation (4-1).

...(4) The extension of the spring is Δxs - 3h (However, Δxs is the formula ■
reference).

The amount of change in the plane angle β is −Δβh−sh, and Δβh is expressed by the following equation.

The above relationships are similarly determined for the other springs 42, 43, and 44, and Table 5 below is obtained by arranging them.

Considering the balance of the force and moment acting on the lens barrel when the spring is displaced more than the table above, first, the sum of the vertical forces is calculated by the following formula (4-3)% Formula % This (4-3) Since the equation becomes zero from equation (■), it can be seen that the vertical forces are balanced as a whole.

The sum of forces in the optical axis direction is given by the following equation (4-4).

4[-(Tsir++xΔCtv- to Δxscoso+
)cosβΔβh+(TcosO1!Δ(Mv”kΔX
sS 1not) s inβΔc<h−nimux, 5in
o+sinβΔ+MylSyS1゜・・・(4-4) Substituting the above formula
Δ(th-ΔxBsino+Δci:v)sinβ・S
w・Sh...(4-5).

Although the value of this equation (4-5) is not zero, 2 of Sw and Sf
The movement of the lens barrel in the horizontal direction can be ignored since it is the next minute amount.

The sum of horizontal and lateral forces is given by the following equation (4-6).

4(T (c, oscxcosβΔβh+sin/1s
incxΔαh)”kΔxscosoisinβ)S...(4-6) Substituting the above equation (■) into this equation (4-6), -Sh
is obtained, and the spring constant in the optical axis direction is larger than 4. Therefore, this large spring constant causes the lens barrel 1 to move to follow the shift of the fixed sheath 3 in the horizontal and lateral directions.

Next, consider the rotation of the lens barrel.

The sum of moments in the pitching direction acting on the lens barrel is given by the following equation (4-7).

4 [T(Lcoso+Am1.+jM(cosol!
sinβΔβh-coSf3sincxAcutionh))k
ΔXs (Lstncv+j=rcoso+cosβ)
]Sh...(4-7) When the above equation (2) is substituted into this equation (4-7) and rearranged, this equation becomes zero, and it can be seen that the moments in the pitching direction are balanced.

The sum of moments in the yawing direction acting on the lens barrel is given by the following equation (4-8).

4 (1, sxnβ+hcO5β) (TsincxA+
xv- to ΔxHcosci+) Sw...(4-8
) When the above equation (2) is substituted into equation (4-8), it becomes zero, so it can be seen that no yawing occurs in the lens barrel 1 in this case as well.

The sum of moments in the rolling direction acting on the lens barrel is given by the following equation (4-9).

4-r￥ (TCO ChaosΔo+v”kΔxssincy)
(cosy+5ino+sinβ) AllKvSwS
h...(4-!l) By substituting the above formula (■) into this formula (4-9), the following formula (4
-10) is obtained.

Since the value of this equation is not τ or is a second-order infinitesimal amount of Sw and Sf, the movement of the lens barrel in the rolling direction can be ignored.

As described above, even if the fixed exterior and the lens barrel undergo relative displacement in the horizontal and lateral directions, the lens barrel will not undergo any inconvenient movement that would degrade the photographed image.

(V) When the fixed sheath 3 is rotated in the rolling direction. FIG. 8 shows the changes in each spring that occur when the fixed sheath 3 is rotated in the rolling direction.
(f) illustrates changes in the spring 41.

The amount of change in the spring angle α is −Δαr ·Or, and Δαr
is expressed by the following equation (5-1).

The stretch of the spring can be ignored.

The amount of change in the plane angle β is −Δβr·Or, and Δβr is expressed by the following equation.

The above relationships are similarly determined for the other springs 42, 43, and 44, and Table 6 below is obtained by arranging them.

Considering the balance of forces and moments acting on the lens barrel when the spring is displaced more than the table above, first, the sum of vertical forces is calculated by the following formula (5-3)% Formula % This (5-3) Since the equation becomes τ from equation (■), it can be seen that the vertical direction is balanced as a whole.

The sum of forces in the optical axis direction is given by the following equation (5-4).

4T (cosys inβΔβ, -coSI3s i
nyΔ(VjL ・-・(5-4) this (4-4)
Substituting the above equation (■) into the equation and rearranging it, we find that it is zero and is under the balanced condition.

The sum of horizontal and lateral forces is given by the following equation (5-5).

4 ((TsinyΔci!v-kaxscos fell)
cosβΔβr−(Tcos Δxsin
o+) sinβΔ(My) Sw'f'r...
・(5-5) Substituting the above formula ■ into this formula (5-5), 4ksin
βΔIIMrSJr (5-6
), and the value of this equation (5-6) is not a drop, but Sw
Since θ1 and θ1 are minute amounts, horizontal displacement of the lens barrel due to rolling of the fixed exterior can be ignored.

Next, consider the rotation of the lens barrel.

The sum of moments in the pitching direction acting on the lens barrel is given by the following equation (5-7).

(5-7) By substituting the above equation (2) into this equation (5-7) and rearranging, the following equation (5-8) is obtained.

Since the value of this equation (5-8) is not zero or is a second-order infinitesimal amount of Sw.Or, rotation of the lens barrel in the pitching direction due to rolling of the fixed exterior can be ignored.

The sum of moments in the yawing direction acting on the lens barrel is given by the following equation (5-9).

...(5-9) Substituting the above equation (2) into this equation (5-9), this becomes ; Therefore, it can be seen that yawing does not occur in the lens barrel 1 in this case as well.

The sum of moments in the rolling direction acting on the lens barrel is given by the following equation (5-10).

(5-10) This equation indicates the restoring torque in the rolling direction, the coefficient of Or becomes an isometric spring constant, and it can be seen that the lens barrel 1 follows the movement in the rolling direction.

From the above, it can be seen that even if the fixed exterior and the lens barrel rotate relative to each other in the rolling direction, the lens barrel does not undergo any inconvenient movement that would degrade the photographed image.

As explained in (Tl+) to (V) above, the spring mechanism of this example has a large spring constant of 4 in the vertical, horizontal, and optical axis directions, and also has a large restoring torque in the rolling direction. Even when the camera is bent under its own weight, the rotation of the lens barrel relative to the rotation of the fixed exterior can be kept very small, and this anti-vibration function can be used practically as an anti-vibration mechanism in this type of photographic equipment. can demonstrate.

(Effects of the Invention) The present invention supports the lens barrel by floatingly balancing it in space using the spring mechanism configured as described above, thereby making the entire imaging device smaller and lighter. In this case, there is an effect that it becomes possible to take pictures without causing deterioration of the picture plane.

[Brief explanation of the drawing]

The drawings are for explaining an embodiment of the vibration isolating support device according to the present invention, and are shown in FIGS. 1(a), (b), and (c).
, (d), and (a) are diagrams showing an outline of the configuration of the spring mechanism of the embodiment, with FIG. 1(a) being a front view as seen from the direction of the photographing optical axis, and FIG. 1(b) being a side view. , Figure 1 (C)
is a plan view, and FIG. 1(d) is a view taken along arrow A in FIG. 1(a). FIG. 1(e) shows a perspective view of a turnbuckle-type tension adjustment mechanism forming a connecting portion of the spring mechanism. Figure 2 (a), (b), (c), (d)
, (e) and (f) are diagrams schematically showing the state of support by the spring mechanism, Figure 2 (a) is a front view as seen from the direction of the photographing optical axis, and Figure 2 (b) is a side view. 2(C) is a plan view, FIG. 2(d) is a view in the direction of arrow A in FIG. 2(a), FIG. 2(e) is a plan view of the spring 41, and FIG. 2(f) is a sectional view taken along line B-B in FIG. 2(c). Figure 3 (a), (b), (c), (d),
(e) and (f) are diagrams schematically showing a state in which the lens barrel supported by a spring mechanism is displaced downward by a certain length due to its own weight, and Fig. 3 (a) is a view from the direction of the photographing optical axis. Figure 3(b) is a side view, Figure 3(C) is a plan view, Figure 3(d) is a sectional view taken along line B-B of Figure 3(C), Figure 3(e) 3(f) is a plan view of the spring 41, and FIG. 3(f) is a diagram showing the actual length of the spring 41 deformed by the above displacement. Each of (a), (b), (c) in Figures 4 to 8
, (d), (e), and (f) are diagrams for explaining the movement of the lens barrel and spring when the fixed exterior is shifted or rotated, and each diagram (a) is similar to Figure 2 (a). ) corresponding figure,
Each figure (b) is a figure corresponding to figure 2 (b), each figure (C) is a figure corresponding to figure 2 (C), each figure (d) is a figure corresponding to figure 2 (d)
Each figure (e) shows a figure corresponding to FIG. 2(e), and each figure (f) shows a figure corresponding to FIG. 2(f). 1... Lens barrel 3... Fixed exterior 41 4
2 43 44...Spring 50...Photographing optical axis 60...Horizontal plane and other 4 people's armpits

Claims (1)

[Scope of Claims] 1. A lens barrel integrally equipped with a photographing optical system and an imaging means on the rear side of the photographing optical axis, by a fixed body that surrounds the outer periphery of the lens barrel in a plane perpendicular to the photographing optical axis. , an anti-vibration support device floatingly supported via a spring mechanism in which four spring members with the same spring force and the same spring constant are stretched as a set, and two planes orthogonal to each other including the above-mentioned photographing optical axis. Two of the four spring members described above are arranged on one plane of The remaining two spring members are arranged on the other of the two orthogonal planes, and these two spring members are connected to the lens barrel on the front side of the photographing optical axis. The two springs on each plane are arranged in a positional relationship with the photographing optical axis as a line of symmetry, and the four springs are connected to a fixed body on the rear side of the photographing optical axis. Furthermore, when the lens barrel is located at the center of the space surrounded by the fixed body, the distance between each connection point of these four springs to the fixed body and the lens barrel and the center of gravity of the lens barrel is calculated. Anti-vibration support device for a photographing device characterized by setting the following relationship: l_1, l_2 = 1/2, r_1, r_2 [where l_1 and l_2 are the respective connection points to the fixed body of the spring and the lens barrel. Distance in the photographing optical axis direction between the center of gravity of the lens barrel,
r_1 and r_2 are distances in a direction perpendicular to the photographing optical axis direction. ].