JP2023039261A - Universal head device and imaging apparatus - Google Patents

Abstract

Kind Code: A1 In an image pickup apparatus that performs pan/tilt drive by direct drive, it is possible to prevent deviation of the pan/tilt angle due to disturbance. A camera unit (110) can be attached to a platform device (100a). The pan head device includes a pan rotating section (111) that supports a camera section rotatably around a tilt rotation axis, a base section (112) that supports the pan rotating section rotatably around the pan rotation axis, an actuator (120, 141) that rotates the camera section and the pan rotation section at a reduction ratio of 1:1 by rotating the tilt rotation axis and the pan rotation axis; A rotational load is applied to at least one of the pan rotating shafts in a direction to stop the rotation of the at least one rotating shaft when the at least one rotating shaft is not rotated by the actuator. [Selection drawing] Fig. 3

Description

The present invention relates to a platform device of an imaging device capable of pan rotation or tilt rotation, and more particularly to a platform device of an imaging device that performs pan/tilt drive by direct drive.

2. Description of the Related Art Video cameras used for shooting in small-scale studios, live broadcasts, and the like are known as imaging devices that pan or tilt a camera unit. These cameras are required to have smooth rotational drive over a wide range of speeds, from low speed to high speed, in order to enable image expression with smooth camerawork. Also, since it is often used with a recording device, the pan/tilt drive is required to be quiet.

A structure using a stepping motor is known as one of the actuators that pan/tilt drive the camera unit. A feature of the stepping motor is that it does not require feedback from a sensor, and the camera can be oriented at a specified pan/tilt angle with simple control. On the other hand, the stepping motor, due to its structure, generates vibration at a frequency corresponding to the step angle when driven, which can cause noise. Moreover, since it is difficult to increase the control resolution structurally, it is also difficult to realize smooth camera work by smooth pan/tilt drive.

Therefore, as a smooth and quiet pan/tilt drive mechanism, a structure called a direct drive mechanism using a DC motor is known. This uses a DC motor as a pan/tilt drive actuator and directly connects the actuator to the pan and tilt axes at a reduction ratio of 1:1. Since it is driven at a speed reduction ratio of 1:1 without using a gear or the like, rattling due to backlash of the speed reduction mechanism does not occur, and smooth rotational drive can be expected. Also, the control resolution of the DC motor depends on an external sensor such as a rotary encoder. Therefore, control with high resolution is relatively easy compared to a stepping motor, which also leads to smooth rotational driving. Furthermore, DC motors are also advantageous in terms of noise compared to stepping motors that generate vibrations at a frequency corresponding to the step angle when driven.

For example, Patent Literature 1 discloses a pan/tilt camera control technique using a direct drive mechanism.

JP 2015-114358 A

However, unlike the stepping motor, the DC motor does not generate an exciting force when the rotation is stopped. Therefore, in the conventional technology disclosed in Patent Document 1, there is a risk that the pan angle or the tilt angle may deviate due to disturbance such as vibration of the mounting surface of the imaging device.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a camera platform device capable of preventing deviation of pan/tilt angles due to disturbances in an image pickup apparatus that performs pan/tilt drive by direct drive.

A pan head device as one aspect of the present invention is a pan head device to which a camera unit can be attached, comprising: a pan rotating unit that supports the camera unit so as to be rotatable around a tilt rotation axis; and the pan rotating unit. a base portion that supports the pan rotation shaft so as to be rotatable; and an actuator that rotates the camera portion and the pan rotation portion at a reduction ratio of 1:1 by rotating the tilt rotation shaft and the pan rotation shaft. , wherein rotation of at least one of the tilt rotation axis and the pan rotation axis is stopped when the at least one rotation axis is not rotated by the actuator. It is characterized in that a rotational load is applied in a direction.

Other objects and features of the invention are described in the following embodiments.

Advantageous Effects of Invention According to the present invention, it is possible to provide a camera platform device capable of preventing a deviation of the pan/tilt angle due to disturbance in an image pickup apparatus that performs pan/tilt drive by direct drive.

1 is a perspective view of a video camera of a first embodiment; FIG. 1 is an exploded perspective view of the video camera of the first embodiment; FIG. 4 is a cross-sectional view showing a tilt rotation mechanism of the video camera of the first embodiment; FIG. 4 is a cross-sectional view showing the pan rotation mechanism of the video camera of the first embodiment; FIG. FIG. 11 is a perspective view of a video camera of a second embodiment; 8 is an exploded perspective view of the video camera of the second embodiment; FIG. FIG. 8 is a cross-sectional view showing a tilt rotation mechanism of the video camera of the second embodiment; FIG. 10 is a cross-sectional view showing a pan rotation mechanism of the video camera of the second embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same members are denoted by the same reference numerals, and overlapping descriptions are omitted or simplified.
[First Embodiment]
FIG. 1 is a perspective view showing a video camera 100 as an imaging device according to this embodiment. The video camera 100 has a camera section 110 , a pan rotation section 111 and a base section 112 . The pan rotating section 111 and the base section 112 constitute a camera platform device 100a. The camera unit 110 can be attached to the camera platform device 100a.

The video camera 100 is, for example, a network camera. The video camera 100 is fixedly installed on the ceiling of, for example, a live house or a photography studio. In addition, it is assumed that the video camera 100 is installed on a special device such as an electric slider, and is used for shooting while moving the video camera 100 itself.

Camera unit 110 captures an image of a subject and is rotatable in pan and tilt directions. By rotating the camera unit 110 in the panning direction and the tilting direction and directing it toward the subject, it is possible to shoot moving images for video production and shooting for live distribution. The pan rotating section 111 supports the camera section 110 so as to be rotatable around tilt rotating shafts 115A and 115B (FIG. 3). The base portion 112 supports the pan rotating portion 111 so as to be rotatable around a pan rotating shaft 140 (FIG. 4).

Next, the tilt rotation mechanism in the video camera 100 of this embodiment will be described with reference to FIGS. 2 and 3. FIG. FIG. 2 is a perspective view showing the tilt rotation mechanism of the video camera 100 of this embodiment. FIG. 3 is a sectional view showing the tilt rotation mechanism of the video camera 100 of this embodiment.

As shown in FIGS. 2 and 3, the lens barrel 113 inside the camera section 110 is supported by a barrel support member 114, and the barrel support member 114 has tilt rotation shafts 115A and 115B. . The lens barrel supporting member 114 is supported by a pan base 116 inside the pan rotating section 111 via bearing members 117A and 17B so as to be capable of tilt rotation. Thereby, the camera section 110 is rotatably supported with respect to the pan rotation section 111 around the tilt rotation shafts 115A and 115B.

Here, the rotation of the camera section 110 in the tilt direction is performed by a tilt motor 120 (first actuator) as an actuator. The tilt motor 120 is directly connected to the tilt rotation shaft 115A, and can rotate the camera section 110 in the tilt direction with a reduction ratio of 1:1. Also, the tilt motor 120 is a DC motor.

An electromagnetic brake 121 is connected to the tilt rotation shaft 115B. As a result, a rotation load as a friction load can be applied in a direction that hinders the tilt rotation of the camera section 110 . The electromagnetic brake 121 is a rotating load mechanism. The electromagnetic brake 121 is arranged on the opposite side of the tilt motor 120 with the camera section 110 interposed therebetween.

When the electromagnetic brake 121 is not energized, the rotational load is very small relative to the torque of the tilt motor 120, but when the electromagnetic brake 121 is energized, a large rotational load is applied.

When the camera section 110 is rotated in the tilt direction, the electromagnetic brake 121 is controlled so as to be in a non-energized state, and almost no load is applied to the tilt rotation. On the other hand, when the camera section 110 is not rotated in the tilt direction, the electromagnetic brake 121 is controlled to be in an energized state, and a load can be applied in the direction to stop the tilt rotation of the camera section 110 . As a result, it is possible to prevent the tilt angle of the camera unit 110 from deviating due to disturbance. The disturbance in this case includes vibration of the mounting surface of the video camera 100 and the like.

Note that the load amount of the rotating load in this energized state is automatically determined based on the user's operation and information obtained from a vibration sensor (not shown) arranged inside the camera unit 110 (for example, feedback from the vibration sensor). can be adjusted with

Also, the video camera 100 may be configured to have a non-energization mode in which the electromagnetic brake 121 is always controlled to be in a non-energization state. In the non-energization mode, even when the rotation of the camera section 110 in the tilt direction is stopped, there is almost no rotation load due to the electromagnetic brake 121, so the responsiveness of the start of tilt rotation is high.

As one example of switching the electromagnetic brake 121 to the non-energization mode, the video camera 100 has a function of forcibly switching to the non-energization mode by manual operation of the user. As another example, the mode is switched to the non-energization mode by feedback from a vibration sensor arranged inside the camera section 110 . For example, when the output voltage of the vibration sensor is below a certain value, control is performed to switch to the non-energization mode. In this case, the disturbance such as the vibration of the mounting surface of the video camera 100 can be regarded as small, so it is considered unlikely that the camera section 110 will tilt and rotate unexpectedly due to the disturbance.

Next, the pan rotation mechanism in the video camera 100 of this embodiment will be described.

FIG. 4 is a cross-sectional view showing the pan rotation mechanism of the video camera 100. As shown in FIG. As shown in FIG. 4, the pan base 116 has a pan rotation axis 140 . The pan base 116 is supported by the base portion 112 so as to be pan rotatable. As a result, the pan rotating section 111 is rotatably supported by the base section 112 around the pan rotating shaft 140 .

Here, the rotation of the pan base 116 in the pan direction is performed by a pan motor 141 (second actuator) as an actuator. The pan motor 141 is directly connected to the pan rotation shaft 140 and can rotate the pan base 116 in the pan direction at a reduction ratio of 1:1. Also, the pan motor 141 is a DC motor.

An electromagnetic brake 142 is connected to the pan rotating shaft 140 . As a result, a rotational load can be applied in a direction that hinders the pan rotation of the pan base 116 . The electromagnetic brake 142 is a rotating load mechanism. The electromagnetic brake 142 is arranged between the pan motor 141 and the camera section 110 . Preferably, electromagnetic brake 142 is located between pan motor 141 and pan base 116 .

When the electromagnetic brake 142 is not energized, the rotational load is very small relative to the torque of the pan motor 141, but when the electromagnetic brake 142 is energized, a large rotational load is applied. The electromagnetic brake 142 is controlled to be energized when the pan base portion 116 is not rotating in the pan direction. As a result, it is possible to prevent the pan angle of the camera unit 110 from being deviated due to disturbance. The disturbance in this case includes vibration of the mounting surface of the video camera 100 and the like.

As in the case of the tilt rotation mechanism, the load amount of the rotation load in this energized state depends on the user's operation and information obtained by a vibration sensor arranged inside the camera unit 110 (for example, feedback of the vibration sensor). can be automatically adjusted based on

Further, like the electromagnetic brake 121 of the tilt rotation mechanism, the electromagnetic brake 142 of the pan rotation mechanism may also have a non-energization mode.

In this embodiment, the video camera 100 has been described as having both the tilt rotation mechanism and the pan rotation mechanism described above. However, if the video camera 100 does not require either the tilt rotation mechanism or the pan rotation mechanism, the configuration may include only one of the mechanisms. Also, although the video camera 100 is configured to include both the tilt rotation mechanism and the pan rotation mechanism, the rotation load may be applied to at least one of the tilt axis and the pan axis.

As described above, according to the configuration of the present embodiment, it is possible to prevent deviation of the pan/tilt angle due to disturbance in an image pickup apparatus that performs pan/tilt drive by direct drive.
[Second embodiment]
Next, a video camera 200 of a second embodiment will be described. Descriptions overlapping with those of the first embodiment will be omitted or simplified.

FIG. 5 is a perspective view showing a video camera 200 as an imaging device according to this embodiment. The video camera 200 has a camera section 210 , a pan rotation section 211 and a base section 212 . The pan rotating section 211 and the base section 212 constitute a camera platform device 200a. The camera section 210 can be attached to the camera platform device 200a. The video camera 200 is, for example, a network camera. The video camera 200 can rotate the camera section 210 in pan and tilt directions.

Next, the tilt rotation mechanism in the video camera 200 of this embodiment will be described with reference to FIGS. 6 and 7. FIG. FIG. 6 is a perspective view showing the tilt rotation mechanism of the video camera 200 of this embodiment. FIG. 7 is a sectional view showing the tilt rotation mechanism of the video camera 200 of this embodiment.

As shown in FIGS. 6 and 7, the lens barrel 213 inside the camera section 210 is supported by a barrel support member 214 , and the barrel support member 214 has a tilt rotation shaft 215 . The lens barrel support member 214 is supported by a pan base 216 inside the pan rotating section 211 via a bearing member 217 so as to be tiltable and rotatable. Thereby, the camera section 210 is rotatably supported around the tilt rotation shaft 215 with respect to the pan rotation section 211 .

Here, the rotation of the camera section 210 in the tilt direction is performed by a tilt motor 220 (first actuator) as an actuator. The tilt motor 220 is directly connected to the tilt rotation shaft 215 and can rotate the camera section 210 in the tilt direction with a reduction ratio of 1:1. Also, the tilt motor 220 is a DC motor.

A rotary damper 222 is connected to the tilt rotating shaft 215 via an electromagnetic clutch 221 . The rotary damper 222 is composed of a rotor 222A and a stator 222B, and viscous resistance is generated when the rotor 222A is rotated with respect to the stator 222B. As a result, a rotation load as a viscous load can be applied in a direction that hinders the tilt rotation of the camera unit 210 . The rotor 222A of the rotary damper 222 is connected to the electromagnetic clutch 221 . The electromagnetic clutch 221 and the rotary damper 222 constitute a rotational load mechanism.

When the electromagnetic clutch 221 is in a non-energized state, the rotor 222A can freely rotate with respect to the tilt rotation shaft 215. FIG. Therefore, even if the camera section 210 is rotated in the tilt direction, the rotary damper 222 does not generate viscous resistance. On the other hand, when the electromagnetic clutch 221 is energized, the rotor 222A is fixed with respect to the tilt rotation shaft 215. As shown in FIG. Therefore, when the camera unit 210 is rotated in the tilt direction, the rotary damper 222 generates viscous resistance.

When the electromagnetic clutch 221 is in a non-energized state, the tilt rotation load is reduced, so high-speed and highly responsive tilt drive can be expected. On the other hand, when the electromagnetic clutch 221 is in an energized state, the tilt rotation load increases, so that it is possible to prevent the camera section 210 from unexpectedly tilting and shifting due to disturbance. The disturbance in this case includes vibration of the mounting surface of the video camera 200 and the like.

The non-energized state and the energized state of the electromagnetic clutch 221 may be controlled by the tilt drive speed of the camera section 210 . For example, when the tilt drive of the camera unit 210 is completely stopped or at an extremely low speed, the electromagnetic clutch 221 is energized to prevent the tilt angle from shifting due to disturbance. On the other hand, when it is desired to drive the camera unit 210 at a certain speed or higher, by putting the electromagnetic clutch 221 in a non-energized state, it is expected that even if the torque of the tilt motor 220 is relatively small, high-speed and high-response tilt drive can be expected. can.

The non-energized state and the energized state of the electromagnetic clutch 221 may be switched by manual operation of the video camera 200 by the user. For example, in a use case in which the vibration of the mounting surface is relatively large, such as when the video camera 200 is attached to an electric slider, energizing the electromagnetic clutch 221 can aim to prevent deviation in tilt rotation. On the other hand, in a use case where the camera unit 210 is pan-tilt driven to follow a subject, such as a sports broadcast, the electromagnetic clutch 221 can be deenergized to aim for high-response pan-tilt drive.

Next, a pan rotation mechanism in the video camera 200 of this embodiment will be described.

FIG. 8 is a cross-sectional view showing the pan rotation mechanism of the video camera 200. As shown in FIG. As shown in FIG. 8, the pan base 216 has a pan rotation shaft 240 and is supported by the base portion 212 so as to be pan rotatable. As a result, the pan rotating section 211 is rotatably supported by the base section 212 around the pan rotating shaft 240 .

Here, the rotation of the pan base 216 in the pan direction is performed by a pan motor 241 (second actuator) as an actuator. The pan motor 241 is directly connected to the pan rotation shaft 240 and can pan rotate the pan base 216 at a reduction ratio of 1:1. Also, the pan motor 241 is a DC motor.

A rotary damper 243 is connected to the pan rotating shaft 240 via an electromagnetic clutch 242 . The rotary damper 243 is composed of a rotor 243A and a stator 243B, and viscous resistance is generated when the rotor 243A is rotated with respect to the stator 243B. The rotor 243A of the rotary damper 243 is connected to the electromagnetic clutch 242 . The electromagnetic clutch 242 and rotary damper 243 constitute a rotational load mechanism.

When the electromagnetic clutch 242 is in a non-energized state, the rotor 243A can freely rotate with respect to the pan rotation shaft 240. FIG. Therefore, even if the pan base 216 is to be pan-rotated, no viscous resistance is generated by the rotary damper 243 . On the other hand, when electromagnetic clutch 242 is in an energized state, rotor 243A is fixed to pan rotating shaft 240 . Therefore, when an attempt is made to pan rotate the pan base 216 , viscous resistance is generated by the rotary damper 243 .

By controlling the energized state and the non-energized state of the electromagnetic clutch 242, it is possible to prevent deviation of the pan angle due to disturbances, as in the tilt rotation mechanism.

As described above, according to the configuration of the present embodiment, it is possible to prevent deviation of the pan/tilt angle due to disturbance in an image pickup apparatus that performs pan/tilt drive by direct drive.

Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist.

110, 210 camera section 111, 211 pan rotation section 112, 212 base section 120, 220 tilt motor 141, 242 pan motor

Claims (16)

A platform device to which a camera unit can be attached,
a pan rotation unit that supports the camera unit so as to be rotatable around a tilt rotation axis;
a base portion that supports the pan rotating portion so as to be rotatable around a pan rotating shaft;
an actuator that rotates the camera section and the pan rotation section at a reduction ratio of 1:1 by rotating the tilt rotation axis and the pan rotation axis;
At least one of the tilt rotation axis and the pan rotation axis is subjected to a rotational load in a direction to stop the rotation of the at least one rotation axis when the at least one rotation axis is not rotated by the actuator. A pan head device characterized by being hung. 2. The camera platform device according to claim 1, wherein the actuator is a DC motor. 3. The camera platform device according to claim 1, wherein the rotational load is a frictional load. 4. The camera platform device according to claim 3, wherein the rotational load is a rotational load caused by an electromagnetic brake. 5. The camera platform device according to claim 4, wherein said at least one rotating shaft to which said rotating load is applied is connected to said electromagnetic brake. 3. The camera platform device according to claim 1, wherein the rotational load is a viscous load. 7. The camera platform device according to claim 6, wherein the rotational load is a rotational load caused by an electromagnetic clutch. Equipped with a rotary damper consisting of a rotor and a stator,
8. The camera platform device according to claim 7, wherein said at least one rotating shaft to which said rotating load is applied is connected to said rotary damper via said electromagnetic clutch. 9. The camera platform device according to any one of claims 1 to 8, wherein the load amount of the rotational load is adjustable. 10. The camera platform device according to claim 9, wherein the load amount is adjustable by a user's operation. further comprising a vibration sensor arranged inside the camera unit,
10. The camera platform device according to claim 9, wherein the load amount can be automatically adjusted based on information obtained by the vibration sensor. further comprising a rotational load mechanism for generating the rotational load;
12. The apparatus according to any one of claims 1 to 11, wherein when the rotational load is applied to the tilt rotation shaft, the rotational load mechanism is arranged on the opposite side of the actuator across the camera section. or the camera platform device according to item 1. further comprising a rotational load mechanism for generating the rotational load;
12. The apparatus according to any one of claims 1 to 11, wherein when the rotational load is applied to the pan rotation axis, the rotational load mechanism is arranged between the actuator and the camera section. pan head device. 2. The actuator comprises a first actuator that rotates the camera section at a reduction ratio of 1:1, and a second actuator that rotates the pan rotation section at a reduction ratio of 1:1. 14. The pan head device according to any one of 13. a rotating part to which a camera part can be attached;
a rotating shaft connected to the rotating part;
an actuator that rotates the rotating shaft at a reduction ratio of 1:1;
A pan head device, wherein a rotational load is applied to the rotating shaft in a direction to stop the rotation when the rotating shaft is not rotated by the actuator. a camera unit that captures an image of a subject;
16. An imaging apparatus comprising: the camera platform device according to any one of claims 1 to 15.

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