JPH0886395A - Pan head device - Google Patents

Abstract

PURPOSE: To provide a pan head device which occupies less volume and can realize multi-degree-of-freedom rotating motion. CONSTITUTION: In a pan head device which drives a movable member 1 relative to a fixed member 2, a magnet 5 is attached to at least either one of the movable member 1 and the fixed member 2, and a magnetic circuit through which magnetic flux 11 generated from the magnet 5 flows is formed between the movable member 1 and the fixed member 2. Also a conductive member 4 through which a current I flows in the direction crossed with the magnetic flux 11 is fixed to either of the movable member 1 and the fixed member 2, and the movable member 1 and the fixed member 2 are pivoted on an elastic member 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pan head device, and more particularly to a pan head mechanism for mounting an image pickup device, a lighting device, and the like and changing its direction.

[0002]

2. Description of the Related Art In a large plant such as a power generation facility composed of various kinds of equipment elements, there are many narrow places where people cannot easily enter. Industrial endoscopes are used as typical observation means for piping equipment. However, since this endoscope has a relatively large radius of curvature and cannot secure an observation distance, it is difficult to apply it to a long curved thin tube.

[0003] In order to solve this problem, development of a moving mechanism that mounts necessary observation equipment and moves the inside of the pipe with wheels or legs has been performed at various places. In such a moving mechanism, the observation in the moving direction and the close inspection of the pipe side wall are performed by an ultrasonic image or a video image. However, generally, in order to realize these functions, it is general to take a large field of view and perform front observation and side wall observation at the same time, or to provide individual observation means for each observation direction.

[0004]

However, the above-mentioned apparatus such as the moving mechanism having the observing means mounted thereon has the following problems. That is, when the observation in the traveling direction and the observation of the side wall are to be observed by the same means, the side wall is located in the peripheral portion of the observed image, so that a sufficient observation region cannot be secured. In addition, when an individual observation means is to be provided for each observation direction, generally, the mounting space of the equipment and the load capacity that can be mounted on the moving mechanism are approximately 3 lengths.
The smaller the moving environment is, the less realistic it is because it is reduced by multiplication. A similar problem arises when trying to illuminate the environment instead of mounting the observation means.

Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art, to control the attitude of the observation means in various directions, to generate driving force even in a narrow environment, and to reduce the occupied volume. To provide a pan head device.

[0006]

To achieve the above object, a head mechanism of the present invention provides a head device for driving a movable member with respect to a fixed member. A magnet provided on at least one of the movable member and the fixed member so as to form a magnetic circuit, and a conductive member that is fixed to one of the movable member and the fixed member and that allows current to flow in a direction intersecting magnetic flux. It has a member and an elastic member which supports the movable member and the fixed member.

In the above-mentioned head device, it is preferable that the conductive member is provided with a plurality of pairs of electrodes for switching a direction of a flowing current.

[0008]

A magnetic flux generated by a magnet provided on at least one of the movable member and the fixed member is caused to flow in a magnetic circuit formed between the movable member and the fixed member, and the magnetic circuit is fixed to either the movable member or the fixed member. When an electric current is passed through the conductive member in a direction intersecting with the magnetic flux, the magnetic flux and the current intersect each other to generate a Lorentz force. Since the movable member is supported by the fixed member by the elastic member, the movable member is driven by this Lorentz force. By selecting the direction relationship in which the magnetic flux and the current intersect, the direction in which the Lorentz force acts can be selected, and the movable member can be driven to have a desired posture.

While one of the electromagnetic fields is formed, it is possible to act on a plurality of other fields.
Obviously, the space occupied is reduced compared to the case where one field acts on one field as seen in a normal motor. By allocating a movable member to a field in which a plurality acts on one of the two kinds of fields described above, a plurality of independent movements can be realized in a small area, so that it is a very effective means for constructing a micro mechanism. Become. In addition, these means are superior in terms of space efficiency and reduction of the number of parts compared to the method of individually mounting a motor or the like and stacking them to construct a motion mechanism with multiple degrees of freedom, and therefore depend on the small number of parts. In addition to ensuring the reliability that often occurs, the driving force acts in parallel, so that the cumulative error in determining the position and orientation can be reduced as compared with the above serial method. Further, in the method of supporting the movable member and the fixed member via the elastic member, since the force transmission with a maximum of 6 degrees of freedom can be performed by one element part, it is significantly larger than the case where the hinges and sliders are stacked to secure the same degree of freedom. The space efficiency can be improved, and the reliability and the cumulative error can be reduced for the same reason as described above.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a head device according to an embodiment of the present invention. First, a first embodiment of the present invention will be described with reference to FIGS. In FIG. 1, the movable member 1 is supported by a fixed member 2 by an elastic member 3. The movable member 1 is arranged so as not to contact the fixed member 2.

The movable member 1 is formed by sandwiching a cylindrical movable body-side permanent magnet 5 magnetized in an axial direction having an air gap in the center between cylindrical yoke 6 and 7. The yokes 6 and 7 also have a void formed in the center, and the end of the yoke 7 is formed with a substantially semispherical convex surface.

The fixed member 2 has a spherical shell-shaped conductive member 4 having a substantially semi-spherical concave surface facing the convex surface of the end of the yoke 7.
Is attached. The curvature of the convex surface of the end of the yoke 7 is equal to the curvature of the concave surface of the conductive member 4, and the elastic members 3 are arranged so as not to come into contact with the fixed member 2 even if the movable member 1 moves.
Supported by The fixed member 2 has a fixed body side yoke 9 in which the conductive member 4 is embedded, and a fixed body side permanent magnet 10 attached to the fixed body side yoke 9. Fixed body side yoke 9
The fixed body side permanent magnet 10 has a cylindrical shape with a diameter larger than the yokes 6 and 7 and coaxial therewith. The fixed body side permanent magnet 10 is magnetized in the same direction as the movable body side permanent magnet 5.

The elastic members 3 are arranged at positions that form an angle of 90 degrees with each other, and are stretched between the side portions of the yoke 6 and the upper surface of the fixed body side yoke 9.

An image pickup device and a lighting device (not shown) are attached to the upper surface of the yoke 6.

A magnetic circuit passing through the conductive member 4 is formed between the movable member 1 and the fixed member 2, and a magnetic flux B shown by a reference numeral 11 as shown by a dotted line in FIG. Flowing.

A plurality of electrodes 4a are formed on the circumference of the conductive member 4,
4b, 4c, and 4d are provided at positions at 90 degrees to each other. For example, the electrode 4a and the electrode 4b form a pair, and the electrode 4c and the electrode 4d are connected to a current source (not shown) so as to form another pair. The electrode 4a and the electrode 4
c may form a pair, and the electrode 4b and the electrode 4d may form another pair. Electrodes 4a, 4b, 4c, 4d
Is supplied with electric current through the electric wire 13.

Next, the operation of this embodiment will be described with reference to FIGS. FIG. 2 is a diagram in which the spherical shell-shaped conductive member 4 is partially extracted and shown. Electrode 4a and electrode 4b
Between the electrode 4b and the electrode 4a.
A power line 15 shown by a broken line is formed inside the conductive member 4, and the current I flows along the power line 15. The power line 15, that is, the current I, is emitted radially from the electrode 4b, travels on the surface of the spherical shell and inside, and reaches the electrode 4a.

When the magnetic flux 11 acts, a Lorentz force 16 is generated in a direction orthogonal to each power line 15 and the magnetic flux 11. Since the power line 15 flows along the spherical shell conductor,
The Lorentz force 16 acts in the tangential direction of the spherical shell conductor. Therefore, the Lorentz force 16 acts on the spherical shell conductor as a rotational force about the current application direction 18. In this embodiment, since the spherical shell conductive member 4 is fixed to the fixed member 2, the above-mentioned rotational force acts as a reaction force on the movable member 1 side, and eventually the above-mentioned movable member 1 generates this rotational force. It rotates in the opposite direction to the direction while being supported by the elastic member 3.

Next, as shown in FIG. 3, consider the case where a current I flows between the electrodes 4c and 4d in the direction from the electrode 4d to the electrode 4c. A power line 15 shown by a broken line is formed inside the conductive member 4, and the current I flows along the power line 15. The power line 15 radiates radially from the electrode 4d, runs on the surface and inside of the spherical shell, and reaches the electrode 4c. When the magnetic flux 11 acts, a Lorentz force 16 is generated in a direction orthogonal to the power lines 15 and the magnetic flux 11. Since the power line 19 flows along the spherical shell conductor, the Lorentz force 16 acts in the tangential direction of the spherical shell conductor, and therefore the Lorentz force 16
Acts on the conductive member 4 as a rotational force with the current application direction 21 as a rotation axis. The Lorentz force 16 is combined as a rotational force about a rotation axis 21 orthogonal to the rotation axis 18, and as a reaction, the movable member 1 is driven in a direction orthogonal to the case shown in FIG. 2.

Since the plurality of elastic members 3 can be basically supported in the movement directions of 6 degrees of freedom, it is possible to support the movable member 1 so that the movable member 1 can be rotated about an arbitrary axis. .

FIGS. 2 and 3 illustrate the application of currents in directions orthogonal to each other. However, if currents are applied so as to connect 4a and 4b, 4c and 4d, the power line is formed in a 45-degree direction. Therefore, the movable member 1 is driven by receiving a reaction in a direction corresponding to the applied current direction. By appropriately changing the combination of current application to these current application means with time or space, the movable member 4 can be rotated with three degrees of freedom orthogonal to the space. At this time, since the movable member 1 is supported by the elastic member 3 as described above, the rotational movement is not restricted within the range in which the elastic member 3 elastically functions.

It is needless to say that the same effect can be obtained by attaching the conductive member 4 to the movable member 1 without attaching it to the fixed member 2. At this time, the direction of movement of the movable member 1 is different from the case where the conductive member 4 is attached to the fixed member 2 as described above, and the Lorentz force 16 acting on the conductive member 4 is different.
Match the direction of rotation by.

Next, a second embodiment of the present invention will be described with reference to FIG. In this embodiment, instead of the permanent magnet 5 shown in FIG. 1, a coil is wound around the movable member 1 to dispose the electromagnet 25.

In this embodiment, the magnet corresponding to the fixed member side permanent magnet 10 on the fixed member 2 side in FIG. 1 is omitted. It is also possible to dispose an electromagnet at the end of the fixed member 2 as a magnet corresponding to the fixed body side permanent magnet 10.

In the embodiment shown in FIG. 1, the amount and direction of the magnetic flux by the permanent magnet 5 and the like are constant. In this embodiment, the amount and direction of the magnetic flux can be changed by changing the current applied to the coil. . Therefore, by controlling one or both of the current applied to the spherical shell-shaped conductive member 4 and the current applied to the coil of the electromagnet 25, the movement direction of the movable member 4 can be variously controlled. become.

Next, a third embodiment of the present invention will be described with reference to FIG. The movable member 30 to which the image pickup device and the lighting device are attached has a spherical bearing 3
2 is attached. The bearing portion 32 has means for reducing friction on the fixing member 35, for example, a rolling member 36.
, And is rotatably mounted. The rolling member 36 may be replaced with a suitable lubricant or the elastic member 3 as shown in FIG. The end portion of the yoke 31 has a hemispherical shape as in the case of FIG.

The fixing member 35 includes a yoke 41 and a cylindrical yoke 4.
1 has a spherical shell-shaped conductive member 40 embedded therein. A permanent magnet 37 magnetized in the radial direction is attached to the fixing member 35. The fixed member 35 is provided with a cylindrical yoke 39 so as to guide a magnetic flux 38 generated by the permanent magnet 37. The magnetic flux generated from the permanent magnet 37 flows through the yoke 51, flows through the spherical bearing 32 to the yoke 31, and flows through the conductive member 40 to the yoke 41.

When a current is applied to the conductive member 40, a Lorentz force is generated, and the movable member 30 is driven so as to change its posture by this reaction.

In this embodiment, since the rotation of the movable member 30 is mainly supported by the spherical bearing portion 32, the conductive member 30
The shape of the end of the yoke 31 on the side of the movable member 30 opposite to the end of the movable yoke does not need to exactly match the curvature.

Further, as explained in FIG. 1, the conductive member 4
0 may be attached to the movable member 30 side. Further, an electromagnet using a coil may be used instead of the permanent magnet 37. In this embodiment, unlike the case shown in FIGS. 1 and 4,
Since the magnetic path has a closed loop, the energy of the magnetic force source can be more effectively used for driving the movable member 30.

Next, a fourth embodiment of the present invention will be described with reference to FIG. In this embodiment, the fixing member 45 has a cylindrical yoke 46, and a permanent magnet 47 serving as a magnetic force source is arranged inside the yoke 46. Yoke 4 of permanent magnet 47
A cylindrical yoke 48, one end of which is hard to form a concave surface, is attached to the opposite side of 6. The one end of the yoke 48 is concave so that the magnetic flux flowing on the convex surface of the conductive member 54 enters the surface of the yoke 48 vertically.

A plurality of (four in this embodiment) holes 50 are drilled at one end of the yoke 46, and a film-like elastic member 51 is stretched inside the holes 50. A high-rigidity member 52 in the form of a small diameter column is provided so as to penetrate through the membrane-like elastic member 51. On one side of the high-rigidity member 52, a storage member 53 for installing an illumination device of the imaging device is attached, and on the other side, a spherical-shell-shaped conductive member 54 is installed on an attachment member 55.

FIG. 6B shows the XOY cross section in FIG. 6A. Since the magnetic flux generated by the permanent magnet 47 flows through the yoke 46 along a closed path along the magnetic path 60 indicated by a broken line, if an electric current is applied to the conductive member 54 that crosses the yoke 46, an electromagnetic Lorentz force acts. Storage member 53 connected to the conductive member 54 by the high-rigidity member 52
Performs a rotational movement with a posture variation within a range in which the membrane elastic member 51 is elastically deformed. The permanent magnet 47 may be replaced with an electromagnet. Further, the yoke 48 can be omitted. The conductive member 54 is connected to the yoke 4 on the fixing member 45 side.
You may attach it to 8.

If the direction of rotational movement is restricted by the spherical bearing 32 shown in FIG. 5, it is not necessary to strictly limit the shapes of the conductive member 54 and the fixed-side yoke 48 facing the conductive member 54.

The conductive members described in the above-mentioned first to sixth embodiments may be constructed by molding a conductive material into a thin foil shape or by arranging fine linear conductive materials in a blind shape. It may be molded, or a part of the coil molded into a flat shape may be used. In the latter two cases, the current direction is determined by the direction of the wire, but in this case, the conductive members formed in the desired wire direction may be used in an overlapping manner.
For example, to obtain the current directions shown in FIGS. 2 and 3,
Two conductive members constructed by arranging wire rods along the dotted lines in each drawing are prepared and then stacked. When the conductive members are stacked in this manner, the thickness of the conductive members is comprehensively increased, and the distance of the void crossing the magnetic flux orthogonal to the conductive members is also increased, resulting in an increase in magnetic resistance for the magnet. The magnetic flux density will decrease and Lorentz force will decrease,
This can be easily solved by increasing the magnetic pole area of the permanent magnet or the like. The magnetic resistance is roughly proportional to the distance of the air gap, but when supplementing this with the magnetic pole area of the permanent magnet, the amount of change related to the increase of the magnetic pole area can be suppressed to the square root of the air gap due to the dimension relationship between the length and the area. it can. Therefore, the overall size of the pan head device does not significantly increase with an increase in the pole area.

[0036]

As described above, according to the structure of the present invention, in the magnetic field formed in the driving mechanism, the movable members on which the driving force due to the electromagnetic interaction acts in parallel are arranged, and these driving members are driven. Since the forces can be controlled independently, the occupied volume can be made extremely smaller than that of the platform device configured by stacking single-function actuators.

Further, since the movement of the camera platform for mounting the image pickup device and the like is supported by the elastic member in a multi-degree of freedom, it is still different from the posture movable mechanism formed by stacking a plurality of bearings and guide mechanisms. The occupied volume can be reduced. Since these structures have a smaller number of parts than the stacked type, it is possible to provide a tripod head device having high reliability and a large degree of freedom of movement even when applied to a narrow space.

[Brief description of drawings]

FIG. 1 is a plan view (a) and a vertical sectional view (b) showing a schematic configuration of an embodiment of a platform device according to the present invention.

FIG. 2 is a plan view (a) and a cross-sectional view (b) showing only a conductive member.

FIG. 3 is a plan view (a) and a sectional view (b) showing only the conductive member in the case of changing the current direction from the case in FIG.

FIG. 4 is a vertical sectional view (b) showing a schematic configuration of another embodiment of the camera platform device according to the present invention.

FIG. 5 is a vertical cross-sectional view showing a schematic configuration of still another embodiment of the platform apparatus according to the present invention.

FIG. 6 is a vertical sectional view (b) showing a schematic configuration of another embodiment of the camera platform device according to the present invention, and AA in the vertical sectional view (b).
Sectional view (a) as viewed from above.

[Explanation of symbols]

 Reference Signs List 1 movable member 2 fixed member 3 elastic member 4 conductive member 4a, 4b, 4c, 4d electrode 5 permanent magnet 6, 7, 9 yoke

Claims (2)

[Claims] 1. A pan head device for driving a movable member relative to a fixed member, wherein at least one of the movable member and the fixed member is formed so as to form a magnetic circuit between the movable member and the fixed member. A magnet provided, a conductive member that is fixed to one of the movable member and the fixed member and that allows a current to flow in a direction intersecting with the magnetic flux, and an elastic member that supports the movable member and the fixed member. Head device characterized by. 2. The pan head device according to claim 1, wherein the conductive member is provided with a plurality of electrodes for switching a direction of a flowing current.