JPH03205970A - Television camera truck for pipe inside observation - Google Patents

Abstract

PURPOSE:To instantaneously detect a position in the circumferential direction of an object to be photographed on the inside surface of a pipe by detecting the turning of a truck by one piece of encoder interlocked with a weight and returning a television camera head and the encoder to fixed positions in accordance with the rotated quantity. CONSTITUTION:A television camera head 4 is attached integrally with a supporting rod 8 attached as to be turnable through a bearing to a casing 1, and also, by a motor 3-2 integrated into the head 4 and an oscillating mechanism consisting of gears 3-3, 3-4, a television camera 3 is oscillatable. The rotation quantity of truck is detected by an encoder 15 interlocked through a gear with a weight 12 suspended and provided so as to be freely rotatable through a bearing on a television camera head supporting rod 8. When the rotation quantity of the truck is detected, the television camera head 4 and the encoder 15 are rotated by a motor 23 contained in the casing 1 in accordance with its rotation quantity and held in the original positions, that is, they are inserted into the pipe in the beginning. In such a way, the position in the circumferential direction of an object to be photographed on the inside surface of the pipe can be detected quickly and with high accuracy by one piece of encoder.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a television camera truck for observing the inside of pipelines for inspecting the inner surface of pipelines such as gas and water pipes. This system is equipped with a function to accurately detect the circumferential position of the subject inside the pipe, even against rolling of the TV camera cart that inevitably occurs while traveling inside the pipe, and is also equipped with a swing mechanism. Regarding TV camera trolleys for use in television cameras.

Conventional technology: A television camera trolley that observes the condition of the inner surface of a pipe such as a vibrating line travels along the inner surface of the tube and photographs an object on the inner surface with a television camera, which is then displayed as a two-dimensional image using a television image projection device installed outside. It has come to be projected as such.

However, because the TV camera cart inevitably rolls as it rotates from side to side while traveling inside the tube, the circumferential position of the object inside the tube displayed on the television image projection device may not be accurate. The problem is that I can't figure it out.

As a countermeasure against this problem, conventional methods have been to attach multiple encoders to the TV camera cart, measure the rotation angle of the cart itself and the rotation angle of the TV camera head, and calculate the circumferential position of the cart within the pipe from these two measured values. I'm looking for it.

However, installing multiple encoders on a TV camera trolley means that the number of signal cables increases accordingly, which increases weight and reduces running performance when traveling long distances. When confirming the position of a subject, calculations such as subtracting the output values of each encoder are required, and detection takes time.
Furthermore, there is a problem in that the counting error of each encoder becomes large and the detection accuracy decreases.

Problems to be Solved by the Invention Conventional TV camera carts that employ a method that uses multiple encoders to detect the position of objects inside the tube in the tube circumferential direction have low long-distance running performance as described above, and This method has drawbacks such as it takes time to detect the circumferential position of the subject and the detection accuracy is poor.

In order to eliminate these conventional drawbacks, the present invention aims to provide a television camera truck having a function of quickly and accurately detecting the circumferential position of an object on the inner surface of a tube with a single encoder.

Means for Solving the Problems The present invention is a means for detecting the position in the circumferential direction of an object on the inner surface of a tube, by detecting the rotation of the cart with a single encoder linked to a weight, and detecting the amount of rotation of the cart. By adopting a method that returns the TV camera head and encoder to their normal positions according to the amount of light that has been removed, the weight of the trolley is reduced and long-distance running performance is improved, while the circumferential position of the object inside the tube can be instantly detected. This is what was done.

That is, the gist of the present invention is to provide a television camera trolley for inside a pipe in which a forward-looking television camera device is attached to a cylindrical casing, in which a weight is rotatably suspended from a television camera head support rod rotatably attached to the casing. An encoder that is linked to the weight via a rotation transmission mechanism is rotatably attached to the casing, and a mechanism that uses the encoder to detect the amount of circumferential rotation of the television camera cart, A position regulating mechanism is provided in which the encoder can be rotated together with the television camera head support rod using a built-in motor, and the television camera head is also equipped with a television camera swinging mechanism consisting of a motor and gears. That is.

The working television camera truck has a cylindrical casing to which a forward-looking television camera device is attached. It has a structure that allows it to travel within the pipe using a traveling mechanism consisting of a plurality of rollers attached to the outer periphery, for example, via links and springs.

This television camera trolley is driven within the pipe by a pulling system using lobes or the like or by a self-propelled drive system.

The television camera head is attached to a support rod that is rotatably attached to the casing via a bearing.
Moreover, the television camera can be swung by a swiveling mechanism consisting of a motor and gears built into the head.

The amount of rotation of the trolley is detected by a weight rotatably hanging from the television camera head support rod via a bearing, and an encoder interlocked via a gear.

When the amount of rotation of the trolley is detected, a motor built into the casing rotates the television camera head and encoder according to the amount of rotation to maintain the original position, that is, the state in which it was initially inserted into the tube.

Embodiment FIG. 1 is a side view showing a truck according to an embodiment of the present invention, FIG. 2 is a front view of the same truck, and FIG. 3 is a longitudinal sectional side view showing an enlarged main part of the same truck.

That is, as shown in Figure 1, the television camera truck has a cylindrical casing (1) containing a television camera device, and a large number of rollers (2-2) between a pair of parallel side plates (2-1). The supporting leg (2) is pivoted on a pair of links (2-3> and a spring (2-4) provided in the middle).
) are arranged radially through the rollers, and the rollers travel within the pipe via the roller support legs.

The television camera device built into the casing (1) includes a forward-looking television camera (3) and a television camera head (4).
Under the supervision of the TV camera controller (5) and the TV camera controller (5), the TV camera (3) takes pictures of the subjects in the area and displays them on an external TV image projection device (not shown). There is.

The television camera head (4) is mounted on a hollow support rod (8) rotatably attached via a bearing (7) to a support tube (6) fixed to the center of the front wall (1-1) of the casing (1). 〉 is fixed to the tip with a bolt (9).

The television camera (3) is rotatably attached to the camera head (4) on a rotating shaft (3-1), and a small motor (3-2) built into the camera head (4) moves the television camera (3) to the camera head (4). Gear (3-3) and rotating shaft (3-1) directly connected to the motor
It is possible to swing the head via a gear (3-4) attached coaxially with the head.

A cylindrical body (11) is rotatably fitted to the rear end of the camera head support rod (8) via a bearing (10).
) is equipped with a weight (12) and a gear (13), and is rotatably mounted on a bearing (14) attached to the outside of the camera head support rod (8) on the front wall of the casing (1-1). The gear (16) of the encoder (15) and the gear (1)
3) are engaged with each other through an idle gear (17). The idler gear (17) is supported by a bearing (18) attached to the inner wall of the casing.

The camera head support rod (8) also has a large diameter worm gear (2
l) and a small diameter worm gear (22), and the worm gear (21) is meshed with a wheel (24) driven by a motor (23) fixed to the casing front wall (1-1). The worm gear (22) is connected to the encoder (1).
The wheel (24) and the worm gear (2) are meshed with the gear (25) integrally attached to the gear (25) via the idle gear (17) and the motor (23) is driven.
At the same time, the camera head support rod (8) is rotated via the small diameter worm gear (22), the idle gear (17>) and the gear (25).
5) also has a rotating mechanism.

In the above device, the weight (12) always indicates the 6 o'clock position of the clock, and when the casing (1) rotates, the gear (13) integrated with the weight rotates and the idle gear (17) is rotated. The signal is transmitted to the gear (25) via. The amount of rotation (rotation angle) transmitted to the encoder (15) is output to the outside and detected.

On the other hand, when returning the television camera head (4) to its original position, the motor (23) rotates the camera support rod (8) and the encoder (15) is rotated in the opposite direction by the amount of rotation.
let This maintains the television camera in the state it was initially inserted into the tube.

Effects of the Invention As explained above, the present invention is capable of detecting the amount of rotation of the cart using one encoder that is linked to the weight for detecting the amount of rotation of the cart, and also allows the encoder and the television camera head to be adjusted in accordance with the amount of rotation. It is equipped with a function that can be forcibly rotated using two drive sources and returned to its original position, and a swing mechanism, so even if the TV camera trolley rolls while traveling, it will not require calculation processing to capture the subject inside the tube. In addition to accurately detecting the position, one encoder can detect the rotation amount of the cart and regulate the position of the TV camera head, so fewer signal cables are required compared to conventional TV camera carts that use multiple encoders. As a result of the weight of the truck itself being reduced, it has excellent long-distance running performance and is highly effective in observing the inside of a vibrating line.

[Brief explanation of drawings]

FIG. 1 is a side view showing a truck according to an embodiment of the present invention, FIG. 2 is a front view of the television camera truck, and FIG. 3 is an enlarged longitudinal sectional side view of the main parts of the television camera truck. 1... Cylindrical casing 2... Support leg 3... Television camera 4... Television camera head 8... Camera head support rod 12... Weight 15... Engineering coder 23... motor

Claims (1)

[Claims] In a television camera trolley for observing inside pipes in which a forward-looking television camera device is attached to a cylindrical casing, a weight is rotatably hung from a television camera head support rod rotatably attached to the casing, and rotation is transmitted to the weight. An encoder is rotatably attached to the casing and interlocked via a mechanism, and the encoder detects the amount of rotation of the TV camera cart in the tube circumferential direction, and a motor built into the casing is used to connect the encoder to the TV. A television camera trolley for inside a pipe, characterized in that it is equipped with a position regulating mechanism that can rotate integrally with a camera head support rod, and that the television camera head is equipped with a television camera swinging mechanism consisting of a motor and gears.