JP2013238802A - Counter weight device for television lens device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a counter weight device of a television lens device for appropriately reducing vibration which occurs when a plurality of mobile lens groups move at the same time.SOLUTION: A weight 84 of a counter weight device is moved such that a variation in a center-of-gravity position does not occur with respect to the movement of each of a variable power lens group 44 and a correction lens group 46 as zoom lens groups of a television lens device. When the movement amount of the variable power lens group 44 with a weight WA is expressed with ΔXA, and the movement amount of the correction lens group 46 with a weight WB is expressed with ΔXB, the weight 84 with a weight WC is moved to a position where the movement amount expressed with ΔXC=-(ΔXA×WA+ΔXB×WB)/WC is obtained.

Description

  The present invention relates to a counterweight device for a television lens device, and more particularly for broadcasting to reduce vibration caused by movement of a moving lens group such as a zoom lens group mounted on a television lens device used for broadcasting or for business purposes. The present invention relates to a counterweight device of a lens device.

  TV lens devices used for broadcasting or for business purposes connected to a camera head are also available with a maximum zoom magnification of nearly 100 times. Generally, a television lens device having a large maximum zoom magnification is built in. The individual lens groups are also increased in diameter and become heavy, and the entire lens apparatus becomes large and heavy.

  Such a large lens device is usually used while being supported with a camera head on a support base such as a tripod or a pedestalry. Conventionally, a moving lens group such as a zoom lens group is heavier and more movable. The larger the amount of movement of the lens group, the greater the change in the center of gravity position of the entire lens apparatus due to the movement of the moving lens group, resulting in a situation where vibration due to the movement of the moving lens group cannot be ignored. In particular, when a zoom operation that changes the zoom magnification at high speed is performed on a lens device with a large maximum zoom magnification, the heavy zoom lens group moves at high speed and the lens device is supported by a support base. Even so, there is a situation in which the vibration caused by the movement of the center of gravity of the lens device causes troubles in photographing.

  For example, Patent Documents 1 and 2 have been proposed as techniques for reducing the vibration caused by the movement of the moving lens group. According to these Patent Documents 1 and 2, weights that can move in the optical axis direction of the camera are arranged on the upper part of the camera or on the camera support base, and the weights are moved in conjunction with the movement of the lens group by zooming or focusing. It is disclosed to adjust the weight balance of the camera.

JP-A-8-22068 JP 2010-39350 A

  By the way, if the weight is moved so that the position of the center of gravity including the moving lens group and the weight does not change with respect to the movement of the moving lens group, the moving lens group can be prevented from occurring as a whole. Vibration due to movement of the can be reduced. For example, when only one moving lens group moves, the weight is moved in a direction opposite to the moving direction of the moving lens group with a moving amount proportional to the moving amount of the moving lens group. What should I do?

  Therefore, when controlling the position of the weight with respect to one moving lens group, vibration due to movement of the moving lens group can be appropriately reduced with relatively easy control, and the amount of movement of the moving lens group can be reduced. Further, an appropriate adjustment of the amount of movement of the weight can also be handled by adjusting the magnification of the amount of movement of the weight that can be appropriately performed by the user.

  However, in a lens device called a zoom lens that is used for broadcasting or business, a zoom lens group and a focal point for changing the size of an image so that the focal point does not fluctuate when the zoom magnification is changed. Control is performed to move the correction lens group that corrects fluctuations in a predetermined positional relationship by a cam mechanism or the like. Thus, when a plurality of moving lens groups move at the same time, the movement of the center of gravity is not as simple as when only one moving lens group moves, and appropriate control of weights is not easy. In the above Patent Documents 1 and 2, weight control when a plurality of moving lens groups move simultaneously is not considered, and when a plurality of moving lens groups move simultaneously, those weights are appropriately controlled. Vibration due to movement cannot be reduced.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a counterweight device for a television lens device that can appropriately reduce vibrations that occur when a plurality of moving lens groups move simultaneously. And

  In order to achieve the above object, a counterweight device for a television lens apparatus according to the present invention is obtained by position information obtaining means for obtaining position information of a plurality of moving lens groups of the television lens apparatus, and the position information obtaining means. Moving lens group movement amount calculating means for calculating a movement amount of each of the plurality of moving lens groups from a predetermined reference position based on the position information, and the plurality of movements calculated by the moving lens group movement amount calculating means. A weight movement amount calculating means for calculating a movement amount of the weight so as not to change a gravity center position of the plurality of moving lens groups and the weight based on a movement amount of each of the lens groups; and the weight at a predetermined reference position. Weight driving means for moving to a position corresponding to the movement amount calculated by the weight movement amount calculation means.

  According to the present invention, it is possible to appropriately reduce vibration that occurs when a plurality of moving lens groups move simultaneously.

  Further, the present invention can be configured such that the moving lens group moving amount calculating means calculates the moving amount using unique information corresponding to the model of the television lens device.

  In the present invention, the plurality of moving lens groups may be moving lens groups that move in conjunction with a zoom cam barrel.

  In the present invention, the moving lens group moving amount calculating means is a means for calculating the moving amount using unique information corresponding to a model of the television lens device, and for each rotation angle of the zoom cam barrel. The amount of movement may be calculated using unique information indicating the amount of movement of each of the plurality of moving lens groups from a predetermined reference position.

  In the present invention, in place of the movement amount calculation means, angle detection means for detecting the rotation angle of the zoom cam cylinder, and storage means for storing the relationship between the rotation angle of the zoom cam cylinder and the position where the weight is to be moved; The weight driving means reads out the position to which the corresponding weight should move from the storage means based on the rotation angle of the zoom cam cylinder detected by the angle detecting means, and moves the weight to the read position. It can be made into the form made to do.

  According to the present invention, it is possible to appropriately reduce vibration that occurs when a plurality of moving lens groups move simultaneously.

The side view which showed the television camera system using the counterweight apparatus of this invention The figure which showed the structure relevant to control of the zoom lens group of a lens apparatus. Zoom cam development (A), (B) is the side view and front view explaining the structure of the weight drive mechanism in a counterweight apparatus. Block diagram showing the configuration of the weight drive unit Flow chart showing processing contents (processing procedure) performed by CPU of counterweight device Tables and graphs specifically illustrating zoom data Diagram used to explain the process of calculating weight positions based on zoom data Diagram used to explain the process of calculating weight positions based on zoom data Explanatory diagram used to explain weight control The figure which showed the processing of CPU of the counter weight device with the functional block

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a side view showing a television camera system in which the counterweight device of the present invention is used.

  A television camera system 1 shown in FIG. 1 is a system used when shooting for broadcasting or business use, and a screen-like lens supporter 14 is mounted on a platform 12 supported by a tripod 10 placed on a floor. Is fixed, and a counterweight device 20 is placed on a pedestal 18 on the rear side (right side in the figure) with the mount frame 16 of the lens supporter 14 interposed therebetween.

  Mounted on the upper part of the counterweight device 20 is a shoulder-mounted camera head 22 called an ENG (Electronic News Gathering) camera mainly used for news gathering, and a small monitor 24 is mounted on the upper part of the camera head 22. Is installed.

  On the front side (left side in the figure) of the mount frame 16 of the lens supporter 14, a box-type television lens device 26 for EFP (hereinafter referred to as the lens device 26) is supported in a state of being suspended from the mount frame 16. The lens device 26 is optically and electrically connected to the camera head 22 via the mount frame 16. In addition, the counter weight device 20 is connected to the lens device 26 through a cable so as to be communicable.

  Two operating rods 28 and 30 (the operating rod 30 is not shown) are extended on the pan head 12, and a controller connected to the lens device 26 with a cable at the tip of the operating rods 28 and 30. 32 and 34 (one controller 34 is not shown) is installed.

  According to this television camera system 1, the camera head 22 and the lens device 26 constitute the television camera 2, and a subject image is formed by the imaging optical system provided in the lens device 26. Then, the subject image is photoelectrically converted by a solid-state imaging device included in the camera head 22 and subjected to predetermined signal processing to obtain a video signal of the subject. On the monitor 24, a real-time video imaged by the television camera 2 is displayed.

  The cameraman does not hold the controllers 32 and 34 at the tips of the operation rods 28 and 30 but applies a force in a predetermined direction to the operation rods 28 and 30 to rotate the pan head 12 to perform pan operation of the TV camera 2. The lens device 26 can be adjusted in focus and zoom (focal length adjustment) by operating predetermined operation members of the controllers 32 and 34.

  Further, the counterweight device 20 reduces vibrations caused by movement of the moving lens group during focus adjustment and zoom adjustment by the controllers 32 and 34. This counterweight device 20 does not act effectively only on a specific type of lens device, and is installed outside the lens device for a plurality of types of lens devices as shown in FIG. It works effectively by connecting with.

  In the present embodiment, vibration caused by movement of a moving lens group other than the zoom lens group that moves during zoom adjustment can be ignored, and the counterweight device 20 considers only movement of the zoom lens group. Hereinafter, only the configuration and processing related to the zoom lens group (zoom adjustment) will be described in detail.

  FIG. 2 is a diagram showing a configuration related to the control of the zoom lens group of the lens device 26.

  As shown in the figure, the imaging optical system 27 of the lens device 26 includes, in order from the objective side, a focus lens group 40 that moves in the optical axis direction for focus adjustment, and light for zoom adjustment (focal length adjustment). A zoom lens group 42 that moves in the axial direction, a variable power lens group 44 for changing the size of an image, and a correction lens group 46 that corrects a focal position shift in conjunction with the variable power lens group 44. A zoom lens group 42, an aperture 48 that opens and closes to adjust the amount of light, a master lens group 50 that finally forms a subject image, and the like.

  The variable power lens 44 and the correction lens group 46 constituting the zoom lens group 42 are moved in the optical axis direction by the cam mechanism of the zoom drive unit 58. Although not shown in the drawing, each of the variable power lens group 44 and the correction lens group 46 is held by an individual lens holding frame, and an engagement pin protruding from the lens holding frame is used as a light beam of the lens barrel body. It is supported so as to be movable in the optical axis direction through the axially straight groove. Then, the engaging pin of the variable power lens group 44 inserted through the rectilinear groove engages with the cam groove 62 of the zoom cam 60 shown in the figure, and the engaging pin of the correction lens group 46 engages with the cam groove 64 of the zoom cam 60. ing.

  The zoom cam 60 is formed in a cylindrical shape (columnar shape), and is supported by a fixed portion such as a lens barrel body so as to be rotatable about a central axis thereof. As shown in the development view of FIG. Two cam grooves 62 and 64 are formed. As a result, when the zoom cam 60 rotates, the intersection position of each of the cam grooves 62 and 64 of the zoom cam 60 and the rectilinear groove of the barrel main body changes according to the shape of the cam grooves 62 and 64 and the rotation angle of the zoom cam 60. The variable power lens group 44 and the correction lens group 46 are moved in conjunction with each other according to the intersection position.

  The zoom cam 60 is connected to the output shaft of the motor 66 as shown in FIG. 2 and is rotated by the power of the motor 66. The rotation speed of the motor 66 is controlled by the control circuit 68. It is like that. The zoom cam 60 is connected to a detection shaft of a position sensor 67. Based on a position signal acquired from the position sensor 67, the rotation angle (rotation position) of the zoom cam 60 is changed to the zoom position (the position of the zoom lens group 42). ) Is detected.

  The controller 32 (zoom rate demand) shown in FIG. 1 is connected to the control circuit 68 through the interface circuit 70 of the RS-485 serial communication standard, and a zoom operation based on an operation of a predetermined operation member (thumbing) of the controller 32. The signal is given by serial communication.

  The zoom operation signal is, for example, a signal for instructing the speed, and the control circuit 68 drives the motor 66 to rotate the zoom cam 60 so that the rotation speed corresponds to the instruction speed. As a result, each of the variable power lens group 44 and the correction lens group 46 moves at a speed corresponding to the instruction speed of the zoom operation signal from the controller 32.

  It is also possible to give a signal indicating the zoom position from the controller 3 as a zoom operation signal, and to control the rotation angle of the zoom cam 60 so as to be the indicated position.

  Further, the counter weight device 20 shown in FIG. 1 is connected to the RS-232C serial communication standard interface circuit 72, and the control circuit 68 receives the model name (model) and the controller 32 by serial communication. The value of the given zoom operation signal, information on the current rotation angle (zoom position) of the zoom cam 60 and the like are given to the counterweight device 20.

  Next, the counterweight device 20 will be described.

  FIGS. 4A and 4B are a side view and a front view showing the configuration of the weight driving mechanism 80 in the counterweight device 20. As shown in FIG. 5B, the weight drive mechanism 80 includes a cylindrical fixed cylinder 82 fixed to a housing (not shown), and its central axis is arranged in parallel to the surface on which the housing is installed. It has become so. When the counterweight device 20 is placed on the pedestal 18 of the lens supporter 14 as shown in FIG. 1, the optical axis of the imaging optical system 27 of the lens device 26 and the central axis of the fixed cylinder 82 are arranged in parallel. .

  On the inner peripheral side of the fixed cylinder 82, a disc-shaped (columnar) weight (weight) 84 shown in FIGS. In the fixed cylinder 82, straight grooves 82A, 82B, 82C along the central axis direction at three positions that are equally spaced around the central axis (the central angle is 120 degrees) (only the straight groove 82A is shown in FIG. A) is indicated by a broken line.

  On the other hand, on the outer peripheral surface of the weight 84, engaging pins 86A, 86B, 86C projecting in the radial direction are provided at three positions corresponding to the rectilinear grooves 82A, 82B, 82C. 82 are inserted into the straight-grooves 82A, 82B, and 82C. As a result, the weight 84 moves inside the fixed cylinder 82 in the direction of the central axis of the fixed cylinder 82, that is, in a direction that coincides with the movement direction (optical axis direction) of the variable power lens group 44 and the correction lens group 46 in the lens device 26. Supported as possible.

  A cylindrical cam cylinder 88 is supported on the outer peripheral portion of the fixed cylinder 82 so as to be rotatable with respect to the fixed cylinder 82. The cam cylinder 88 is formed with three cam grooves 88A, 88B, 88C (the cam groove 88A and a part of the cam groove 88B are shown in FIG. 1A), and the three engagements of the weight 84 are formed. Each of the pins 86A, 86B, and 86C is inserted through the rectilinear grooves 82A, 82B, and 82C of the fixed cylinder 82 and engaged with the cam grooves 88A, 88B, and 88C.

  The cam grooves 88A, 88B, 88C are formed in a straight line shape on the development surface and are formed in an oblique direction with respect to the central axis direction of the cam cylinder 88. Therefore, when the cam cylinder 88 rotates, the rotation amount The weight 84 moves in the direction of the central axis of the fixed cylinder 82 by an amount proportional to the movement amount.

  Further, the cam cylinder 88 is engaged with the output shaft of the motor 90 and the detection shaft of the position sensor 92, so that the cam cylinder 88 is rotated by the motor 90 and the rotation angle is detected by the position sensor 92. It has become.

  Each of the motor 90 and the position sensor 92 is connected via a D / A converter 104 and an A / D converter 106 to the CPU 102 in the weight driving unit 100 shown in FIG. Thus, the rotational speed of the motor 90 is controlled by the drive signal supplied from the CPU 102 to the motor 90 via the D / A converter 104, and the rotational speed of the cam cylinder 88 is controlled. The rotation angle of the cam barrel 88 is detected by a detection signal given to the CPU 102 via 106. Therefore, the rotation angle of the cam cylinder 88 can be controlled by the CPU 102, and the position of the weight 84 that moves with a movement amount proportional to the change amount of the rotation angle of the cam cylinder 88 can be controlled.

  The CPU 102 is connected to the lens device 26 through the interface circuit 108 of the RS-232C serial communication standard. The CPU 102 receives the model name (model) of the lens device 26 and the controller 32 through serial communication as described above. The value of the zoom operation signal given to the lens device 26 and information on the rotation angle (zoom position) of the zoom cam 60 can be acquired from the lens device 26.

  The CPU 102 reduces the vibration caused by the movement of the zoom lens group 42 (the variable power lens group 44 and the correction lens group 46) of the lens device 26 by controlling the position of the weight 84 by the following processing.

  FIG. 6 is a flowchart showing the processing contents performed by the CPU 102, and the processing of the CPU 102 will be described in order according to this.

  In step S10 after required initial setting, first, a model name is acquired from the lens device 26, and zoom data (unique information) corresponding to the model of the lens device 26 connected to the counterweight device 20 is selected.

  FIG. 7 specifically illustrates the zoom data, and FIG. 7A shows a part of the zoom data extracted. In the table of FIG. 6A, “zoom cam rotation angle” indicates the rotation angle (rotation position) of the zoom cam 60 and corresponds to the zoom position. In the table, “variable lens group” and “correction lens group” respectively indicate a variable magnification lens group 44 and a correction lens group 46, and “variable lens group” and “correction” for each value of the zoom cam rotation angle. The value of “lens group” indicates the position (position in the optical axis direction) of the variable power lens group 44 and the correction lens group 46 set at each rotation angle of the zoom cam 60. The column in which the rotation angle of the zoom cam 60 is 0 degrees indicates the positions of the variable power lens group 44 and the correction lens group 46 at the tele end.

  FIG. 5B is a graph showing the zoom data, with the horizontal axis representing the rotation angle of the zoom cam 60 and the vertical axis representing the positions of the variable power lens group 44 and the correction lens group 46.

  The zoom data includes weight data of the variable power lens group and the correction lens group.

  Such zoom data corresponding to each of a plurality of models (model names) of the lens device is detachably attached to, for example, a memory built in the counterweight device 20 or the counterweight device 20. The CPU 102 selects the corresponding zoom data based on the model information (model name) acquired from the lens device 26 to which the counterweight device 20 is connected as described above, and uses it in the following processing. The lens device may have its own zoom data, and the zoom data may be given to the counterweight device 20, or the user selects zoom data corresponding to the model of the lens device to which the counterweight device 20 is connected. And you may make it give to the counterweight apparatus 20 with a personal computer.

  In step S12, the cam shape (electronic cam shape) and operating range of the cam cylinder 88 in the counterweight device 20 are determined. That is, the rotation angle of the cam barrel 88 (the position of the weight 84) set corresponding to the zoom position (the rotation angle of the zoom cam 60) in the lens device 26 is determined based on the zoom data.

  Here, if the weight 84 is moved so that the position of the center of gravity of the lens device 26 and the counterweight device 20 does not change, vibration due to the movement of the center of gravity of the lens device 26 can be reduced. For this purpose, the zoom lens group 42 (the variable power lens group 44 and the correction lens group 46) of the lens device 26, and the counterweight device, excluding the part that does not move or the part that is less affected by the movement. The weight 84 may be moved so that the position of the center of gravity considering only the 20 weights 84 does not change.

Therefore, as shown in FIG. 10, the positions (center of gravity positions) of the variable power lens group 44, the correction lens group 46, and the weight 84 in a certain state (arbitrary reference state) are XA, XB, and XC. The weights of the lens group 44, the correction lens group 46, and the weight 84 are WA, WB, and WC. When the gravity center position including all of the variable power lens group 44, the correction lens group 46, and the weight 84 at this time is X0, the following equation (1) is established.
(XA-X0) WA + (XB-X0) WB + (XC-X0) WC = 0 (1)
When it is assumed from this state that each of the variable power lens group 44 and the correction lens group 46 has moved to the positions (XA + ΔXA) and (XB + ΔXB) indicated by broken lines in the figure, the variable power lens group 44, the correction lens group 46, Assuming that the position of the weight 84 is changed so that the center of gravity position including all of the weights 84 is not displaced from the position of X0, assuming that the position is XC + ΔXC, the following expression (2) is established.
(XA + ΔXA−X0) WA + (XB + ΔXB−X0) WB + (XC + ΔXC−X0) WC = 0 (2)
From these equations (1) and (2), the following equation (3) is derived.
ΔXA · WA + ΔXB · WB + ΔXC · WC = 0 (3)
Therefore, if the displacement amounts (movement amounts ΔXA, ΔXB) of the variable power lens group 44 and the correction lens group 46 with respect to an arbitrary reference state are known, the displacement amount of the weight 84 for preventing the center of gravity from moving. (Movement amount ΔXC) can be obtained by the following equation (4).
ΔXC = − (ΔXA · WA + ΔXB · WB) / WC (4)
Further, it is not necessary to obtain a specific value of the gravity center position X0 in the reference state.

  The above (4) is the same when the weight 84 is moved so that the total sum of moments of the variable power lens group 44, the correction lens group 46, and the weight 84 is constant with an arbitrary position as a fulcrum. The movement of the weight 84 so that the center of gravity does not move is equivalent to the movement of the weight 84 so that the moment does not fluctuate.

  The CPU 102 calculates the position of the weight 84 that is set at each zoom position (rotation angle of the zoom cam 60) in the lens device 26 from the zoom data selected in step S10 based on the above equation (4).

  Specifically, in the zoom data in FIG. 7A, for example, the zoom lens 60 at that time is set as a reference state when the telephoto end setting value where the value of the rotation angle (zoom position) of the zoom cam 60 is 0 degree is the reference state. Each position of 44 and the correction lens 46 is defined as a reference position (0). However, the rotation angle of the zoom cam 60 in the reference state is not limited to 0 degrees and can be any rotation angle.

  Then, the position of the zoom lens group 44 and the correction lens 46 at an angle other than 0 degrees of the rotation angle of the zoom cam 60 is converted into a value of the movement amount from the reference position (0), and the conversion as shown in FIG. Generate data. In other words, the positions of the zoom lens group 44 and the correction lens 46 in the zoom data are converted into data representing the amount of movement from the reference position. FIG. 8B is a graph showing the converted data. The conversion data may be generated in advance, for example, when zoom data is selected. However, it is not always necessary to generate the conversion data in advance, and when calculating the position of the weight 84 using the above equation (4). It is only necessary to calculate the data of the necessary movement amount as necessary.

  Subsequently, the movement amount of the weight 84 at each value of the rotation angle (zoom position) of the zoom cam 60 is calculated from the conversion data and the above equation (4), and the weight movement amount data as shown in FIG. Generate. In addition, the value of the movement amount of the weight 84 in FIG. 9 is an example of values calculated assuming that the weights of the variable power lens group 44, the correction lens group 46, and the weight 86 are 300 g, 200 g, and 300 g, respectively. Is negative, but the minus sign is omitted. FIG. 9B is a graph showing the weight movement amount data.

  Since the position of the weight 86 (reference position) in the reference state can be set to an arbitrary position, for example, in the weight movement amount data, the weight 86 is the forefront of the cam cylinder 88 (the position closest to the lens device 26). The reference position of the weight 86 (zoom in this example) so that both the position when moving to the rearmost position and the position when moving most backward are within the movable range of the weight 86 in the weight driving mechanism 80. The position of the weight 86 when the position is at the tele end may be set.

  The weight movement amount data may be generated in advance when zoom data is selected, and stored in the storage means, or when the position of the weight 84 is calculated using the above equation (4). Only calculation of necessary weight movement amount data may be performed as necessary. In addition, the CPU 102 does not perform the calculation for creating the weight movement amount data from the zoom data as described above, but the weight movement amount data created in advance is stored in the storage means, and instead of the zoom data, The weight movement amount data may be read from the storage means.

  As described above, in step S12 in FIG. 6, the position of the weight 84 set at each rotation angle (each zoom position) of the zoom cam 60, that is, the rotation angle of the cam barrel 88 is determined.

  In step S14, the zoom operation signal and the change rate of the zoom position are acquired from the lens device 26, and the specifications of the zoom drive unit 58 in the lens device 26 are determined. That is, it is detected at what speed the zoom position (the rotation angle of the zoom cam 60) actually changes in response to a zoom operation signal given from the controller 32 to the lens device 26. When this process ends, the process proceeds to a process for actually controlling the weight 86.

  In step S <b> 16, a zoom operation signal given from the controller 32 to the lens device 26 is acquired from the lens device 26.

  In step S18, the cam barrel 88 of the weight drive mechanism 80 is driven based on the latest zoom position, the zoom operation signal acquired from the lens device 26, and the weight movement amount data obtained as shown in FIG. The weight 86 is moved to a position corresponding to the zoom position assumed by the zoom position and the zoom operation signal. Here, the movement amounts of the zoom lens group 44 and the correction lens group 46 are obtained using the zoom data of FIG. 7 with respect to the latest zoom position and the zoom position assumed by the zoom operation signal, and the above equation (4) is obtained. The amount of movement of the weight 86, that is, the position where the weight 86 should be moved may be calculated.

  Note that the current zoom position may be acquired from the lens device 26 and the weight 86 may be moved to a position corresponding to the zoom position, but the time required for information transmission from the lens device 26 to the counterweight device 20 or the like. The operation of the weight 86 is delayed depending on the time until the weight 86 starts the operation instructed by the CPU 102 or the like, and particularly when the zoom position changing speed is fast (when the zoom operation is performed at high speed). The effect of the delay may not be ignored. For this reason, as described above, the current zoom position actually set in the lens device 26 is predicted based on the latest zoom position and the zoom operation signal, thereby preventing a delay in the operation of the weight 86. Yes. In order to perform the prediction, the specification of the zoom drive unit is determined in step S14.

  In step S20, information on the current zoom position is obtained from the lens device 26. The information on the zoom position acquired here is used as the latest zoom position information in the next step S18.

  In step S22, it is determined whether or not the zoom position acquired in step S20 corresponds to the position of the weight 86 moved in step S18. That is, it is determined whether or not the zoom position predicted in step S18 matches the zoom position acquired from the lens device 26. However, it is determined not to match only when exactly matching, but if the difference is within an allowable range, it is determined to match, and in that case, the process proceeds to step S26. If it is determined that they do not match, the process proceeds to step S24.

  In step S24, the weight 86 is moved to the position corresponding to the zoom position acquired in step S20 (corresponding position based on the weight movement amount data in FIG. 9), and the position of the weight 86 is adjusted. Then, the process proceeds to step S26.

  In step S26, timer synchronization is achieved, and the process waits for processing from step S16 to step S24 to be performed at predetermined time intervals. And when fixed time passes, it will return to the process of step S16.

  As described above, the control of the weight 84 for reducing the vibration caused by the movement of the variable power lens group 44 and the correction lens group 46 of the zoom lens group 42 that moves in conjunction with each other has been described. Control of the weight 84 to reduce vibration when a plurality of moving lens groups including the moving lens group that moves independently, such as the focus lens group 40, is not limited to the moving lens group, or independently. The control of the weight 84 for reducing vibrations when a plurality of moving lens groups including only the moving lens group that moves is simultaneously moved can also be implemented.

  For example, when the first moving lens group and the second lens group are individually controlled, assuming that the movement amounts when moving from a certain point are ΔXA and ΔXB, the weight 84 is equal to ΔXC calculated by the above equation (4). Should be moved. At this time, the information about the first moving lens group and the second moving lens group can be obtained from the information (position information and control information) about the first moving lens group and the second moving lens group that can be acquired from the lens device 26 by the counterweight device 20. It is necessary to determine the movement amounts ΔXA and ΔXB in the real space, and for this purpose, unique information (corresponding to the zoom data described above) unique to each lens device model is required. By acquiring the unique information in the same manner as the zoom data of the above embodiment, the movement amount ΔXA in the real space of the first moving lens group and the second moving lens group based on the information obtained from the lens device 26, ΔXB can be obtained, and based on this, the amount of movement of the weight 84 for preventing the center of gravity from moving can be determined. Similarly, when there are three or more moving lens groups, the amount of movement of the weight 84 can be determined.

  Using the functional block diagram of the CPU 102 shown in FIG. 11, a series of processing of the CPU 102 related to the control of the weight 84 when an arbitrary plurality of moving lens groups of the lens device 26 are moved simultaneously will be described. The position information acquisition unit 200 acquires position information for grasping the positions of a plurality of target moving lens groups from the lens device 26. As this position information, in addition to the position information detected by the position sensor, an operation signal when acquiring operation signals from the controllers 32 and 34 for predicting the position of each moving lens group as in the above embodiment. Including.

  Based on the position information, the moving lens group moving amount calculating means 202 calculates the moving amount of each moving lens group moved from a predetermined reference position. At this time, the moving lens group movement amount calculating means 202 selects and reads unique information corresponding to the model of the lens apparatus to which the counterweight device 20 is connected from the unique information stored in the storage means 210. The amount of movement is calculated using the unique information.

  The unique information is information necessary for calculating the amount of movement in the real space from the position information acquired by the position information acquisition unit 200. Normally, the unique information is not possessed by the lens apparatus, and the information is acquired in advance. Unique information corresponding to various lens devices is created and stored in the storage means. However, the means for acquiring the specific information necessary for the moving lens group movement amount calculating means is not limited to this.

  When the moving amount of each moving lens group is calculated by the moving lens group moving amount calculating unit 202, the moving amount of the weight 84 from a predetermined reference position is calculated by the weight moving amount calculating unit 204 based on the moving amount. . The amount of movement calculated here is the amount of movement of the weight 84 so that the position of the center of gravity combining the plurality of target moving lens groups and the weight 84 does not change due to the movement of the moving lens group. The above equation (4) can be calculated by an equation that is expanded to the number of moving lens groups.

  When the movement amount of the weight 84 is calculated, the weight 84 is driven by the weight driving means 206, and the weight 84 moves to a position moved by the movement amount from the reference position.

  It should be noted that data for directly determining the weight movement amount from the position information acquired by the position information acquisition means 200 can be stored in the storage means 210 as specific information. In this case, the weight movement amount calculation unit 204 reads out the unique information stored in the storage unit 210 (unique information corresponding to the model of the lens apparatus) and uses the unique information to acquire the specific information. By obtaining the movement amount of the weight 84 from the position information thus obtained, the moving lens group movement amount calculation means 202 is not required.

  In the above embodiment, the counterweight device 20 is installed on the lens supporter 14. However, if the counterweight device 20 is installed on a portion integrally connected to the lens device 26, it can be effectively operated. For example, it can be installed on the upper surface, side surface, lower surface, upper surface of the camera head, pan head 12 or the like of the casing of the lens device 26.

  In the counterweight device 20 of the above embodiment, the weight 84 is moved by the cam mechanism. However, any mechanism for moving the weight 84 may be used.

DESCRIPTION OF SYMBOLS 1 ... Television camera system, 2 ... Television camera, 10 ... Tripod, 12 ... Head, 14 ... Lens supporter, 16 ... Mount frame, 18 ... Base, 20 ... Counterweight apparatus, 22 ... Camera head, 24 ... Monitor, 26 DESCRIPTION OF SYMBOLS ... Lens apparatus, 27 ... Imaging optical system, 28, 30 ... Operation rod, 32, 34 ... Controller, 40 ... Focus lens group, 42 ... Zoom lens group, 44 ... Variable magnification lens group, 46 ... Correction lens group, 48 ... Aperture, 50 ... Master lens group, 58 ... Zoom drive unit, 60 ... Zoom cam, 62, 64 ... Cam groove, 66 ... Motor, 67 ... Position sensor, 68 ... Control circuit, 70, 72 ... Interface circuit, 80 ... Wait Drive mechanism 82 ... fixed cylinder, 82A, 82B, 82C ... straight advance groove, 84 ... weight (weight), 86A, 86B, 86C ... engagement pin, 88 ... force Cylinder, 88A, 88B, 88C ... cam groove, 90 ... motor, 92 ... position sensor, 100 ... weight driving part, 102 ... CPU, 104 ... D / A converter, 106 ... A / D converter, 108 ... interface circuit

Claims (5)

Position information acquisition means for acquiring position information of a plurality of moving lens groups of the TV lens device;
A moving lens group movement amount calculation means for calculating a movement amount from each predetermined reference position of each of the plurality of moving lens groups based on the position information acquired by the position information acquisition means;
Based on the amount of movement of each of the plurality of moving lens groups calculated by the moving lens group movement amount calculating means, the amount of movement of the weight for not changing the position of the center of gravity of the plurality of moving lens groups and the weight. A weight movement amount calculating means for calculating;
Weight driving means for moving the weight from a predetermined reference position to a position having a movement amount calculated by the weight movement amount calculating means;
A counterweight device for a TV lens device equipped with   2. The counterweight device for a television lens apparatus according to claim 1, wherein the moving lens group movement amount calculating means calculates the movement amount using unique information corresponding to a model of the television lens apparatus.   The counterweight device for a television lens apparatus according to claim 1, wherein the plurality of moving lens groups are moving lens groups that move in conjunction with a zoom cam barrel.   The moving lens group moving amount calculating means is means for calculating the moving amount using unique information corresponding to a model of the television lens device, and the plurality of moving lens groups with respect to each rotation angle of the zoom cam barrel. 4. The counterweight device for a television lens apparatus according to claim 3, wherein the movement amount is calculated using unique information indicating a movement amount from each predetermined reference position. Instead of the movement amount calculation means,
Angle detection means for detecting the rotation angle of the zoom cam barrel;
Storage means for storing a relationship between a rotation angle of the zoom cam barrel and a position to which the weight is to be moved;
4. The weight driving unit reads a position to which the corresponding weight is to be moved from the storage unit based on a rotation angle of the zoom cam cylinder detected by the angle detection unit, and moves the weight to the read position. A counterweight device for a television lens device according to 1.

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