Camera for jib crane

Abstract

To provide a jib crane camera capable of visually recognizing a suspended load and the surroundings thereof, being retrofitted, and being easily installed with a simple configuration.SOLUTION: A jib crane camera according to the present invention is attached to the lower part of a jib of a jib crane, and wirelessly transmits captured images for supporting crane work to a monitor located in an operation room, comprising a base fixed to the jib, a camera support erected on the base, and a camera rotatably pivoted on the camera support. The camera is held at a depression angle of 30 to 45 degrees in an optical axis direction in a stationary state.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a camera for a jib crane for assisting crane operations in a jib crane.

Background Art

[0002] A jib crane is a type of crane having a projecting jib (arm), and crane operations can be performed by tilting or rotating the jib. Therefore, a jib crane can perform lifting, lowering, and horizontal movement of a load or a working device (suspended load) over a wide range, and a jib crane operator may perform crane operations in a blind spot area. In such a case, crane operation support means for safely performing crane operations has been proposed.

[0003] For example, Patent Document 1 proposes a jib crane in which a television camera having a downward habit is disposed near a hoisting sheave, and a television receiver is disposed in the driver's cab. This television camera with a downward habit is housed in a housing that always faces the vertical direction due to the gravity of the weight, and is provided with a pin with rotational force adjustment to prevent the housing from swinging due to wind force or the like, so that a good imaging image can be obtained.

[0004] Patent Document 2 discloses a caisson that stores water inside, a traveling rail provided inside the lower part of the caisson, a moving body that is underwater and moves on the traveling rail, a jib crane provided in the upper space of the caisson, a cable that extends from the tip of the jib of the jib crane to the moving body, a landmark that floats on the water surface above the moving body, and an imaging device attached to the tip of the jib. A jib control system for a jib crane has been proposed in which the imaging device images the landmark, and the jib is driven and controlled so that the tip of the jib is positioned above the landmark, and the cable is in a substantially vertical state. This imaging device is composed of a monitoring camera that is suspended downward from the tip of the jib by a gimbal and can be freely tilted in the X and Y directions, and is said to be able to photograph directly below the tip of the jib.

[0005] In Patent Document 3, in a wheeled working machine in which a lower traveling body is provided with a driver's cab and an upper revolving body having a boom that can be raised and lowered is mounted on one side of the driver's cab, a television camera that acquires visual information in a blind spot area where the view from the driver's cab becomes a blind spot is attached to the jib, the lower traveling body, or the upper revolving body so as to be rotatable, tiltable, or swingable by an electric motor, and display means for displaying the visual information acquired by the television camera at a portion where the blind spot exists in the driver's cab is proposed. According to this wheeled working machine, it is said that the driver can recognize the situation and things in the blind spot area by the display means, safely drive the wheeled working machine, and unload a suspended load such as building materials while monitoring the situation in the blind spot area.

[0006] By the way, the crane operation support means is necessary not only for a jib crane but also for other types of cranes. For example, Patent Document 4 proposes a side monitoring device for a crane truck in which the horizontal rotation angle of a side monitoring camera provided at the tip of the boom of the crane truck is automatically controlled by a predetermined program. In this side monitoring device for a crane truck, the side monitoring camera is driven to a predetermined rotation angle by driving a camera drive motor based on a signal from a potentiometer that detects the rotation angle of the camera. And this side monitoring camera can adjust the monitoring angle in the horizontal plane, but it can be further attached so as to be rotatable also in the vertical plane around a horizontal axis, and can be configured to monitor the suspended load directly below during crane operation. Thereby, it is said that it can be used as a side monitoring camera and also as a suspended load monitoring camera.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0008] As shown in Patent Documents 1 to 4, a camera is used as a crane operation support means for visually recognizing or monitoring the suspended load in the blind spot area. Such a camera is disposed at the tip of the boom that looks down on the suspended load, as shown in Patent Documents 1 to 2 and 4. However, in the wheel-type working machine shown in Patent Document 3, the camera is disposed below the central part of the boom (FIG. 8), and it is possible to visually recognize the suspended load and its surroundings.

[0009] In addition, a camera disposed on the boom requires a driving means for tilting the optical axis direction of the camera according to the tilt of the boom. As such a driving means, a motor is generally used as shown in Patent Documents 2 to 4. On the other hand, in Patent Document 1, a mechanical driving means using the gravity of a weight is used, and the camera can have a simple structure. As a crane operation support for a jib crane, a device / means capable of visually recognizing the working area together with the suspended load is preferable. Further, such a visual recognition device / means is preferably inexpensive, can be easily disposed, and can be retrofitted.

[0010] In view of such conventional problems or requirements, the present invention provides a camera for crane operation support disposed on a jib crane, which can visually recognize a suspended load and its surroundings, can be retrofitted, and can be easily disposed with a simple structure.

Means for Solving the Problems

[0011] The camera for a jib crane according to the present invention is a camera for a jib crane that is attached to the lower part of the jib of the jib crane and wirelessly transmits an imaging image for assisting crane operation to a monitor disposed in the cab. The camera has a base fixed to the jib, a camera column erected on the base, and a camera pivotally supported rotatably on the camera column. The camera is held with a depression angle of 30 to 45 degrees in the optical axis direction in a stationary state.

[0012] In the above invention, the camera is pivotally supported rotatably on the camera column at a shaft pivot point P at one end, and is pivotally supported on the camera column via a link that pivotally supports the camera rotatably at a shaft pivot point K at the other end. A deceleration member for restricting the swing of the link is preferably provided at the shaft pivot point P portion.

[0013] Further, the camera preferably has a camera body tilting means for tilting the optical axis direction of the stationary state by about -5 degrees to 15 degrees in the elevation angle direction. Further, the camera can be configured to have a camera tilting means for tilting the optical axis direction of the stationary state by about -10 degrees to 45 degrees in the elevation angle direction.

[0014] In the above invention, the camera column can be configured to have a base column fixed to the base and a camera column body detachably fitted to the base column.

[0015] Further, the camera has a case, a camera body held in the case, a cable for supplying power from a battery to the camera body, an antenna for wirelessly transmitting an imaging image taken by the camera body, and a radio wave reflecting plate covering the antenna. A schematic diagram showing a visual field range can be provided on the side surface of the case.

Effects of the Invention

[0016] The camera for a jib crane according to the present invention can visually recognize a suspended load and its surroundings, can be easily disposed with a simple structure that can be retrofitted, and can assist in safely performing crane operations in a blind spot area.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0018] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The camera for a jib crane according to the present invention is attached to the lower part of the jib of the jib crane, and wirelessly transmits an imaging image for assisting crane work to a monitor disposed in the driver's cab. As shown in FIG. 1, the camera 100 for a jib crane according to the present invention is attached to the jib 3 of the jib crane 1 and is used when performing crane work. When crane work is performed at the upper part of the work building 6 by the jib crane 1, the crane operator in the driver's cab 5 inclines the jib 3 attached to the tip of the telescopic boom 2 of a predetermined length, and raises, lowers or horizontally moves the suspended load suspended from the hook 4 to perform the crane work. At this time, it is sufficient if the jib 3 can be inclined up to a horizontal state at most as shown in FIG. 1. The camera 100 for a jib crane according to the present invention is attached to the lower part of the jib 3. For example, it is attached in the range of 0 to 100 cm from the base end (swing axis) of the jib 3. Therefore, radio waves from the antenna 115 to the antenna on the monitor side are likely to reach. And in normal use when the jib inclination angle is small, a larger imaging image can be obtained compared with the case where the camera is attached to the jib tip. The jib inclination angle means, as shown in FIG. 1, the inclination angle of the jib (jib inclination angle γ) with respect to the vertical line (perpendicular line). If the inclination angle α of the telescopic boom 2 and the inclination angle β of the jib 3 with respect to the telescopic boom are set, γ = α + β. When the jib inclination angle γ is 90 degrees, the jib 3 is in a horizontal state, and when the jib inclination angle γ is 0 degrees, the jib 3 is in a vertical state.

[0019] The camera for a jib crane according to the present invention has a base fixed to the jib, a camera column erected on the base, and a camera pivotally supported rotatably on the camera column. The camera is characterized in that the optical axis direction is held at a depression angle of 30 to 45 degrees in a stationary state. In FIG. 2, An example of a camera for a jib crane according to the present invention is shown. The camera 100 for a jib crane shown in Fig. 2 is pivotally supported via a link 15 on a camera column 12 erected from a base 11 so as to be rotatable. By appropriately setting the length of the link 15, it is possible to prevent the field of view of the camera 10 from being blocked by the jib 3. Also, as will be described below, it is possible to configure the camera to hold the optical axis direction at a predetermined angle and effectively attenuate the shake of the camera.

[0020] The configuration of this camera 100 for a jib crane is shown in Figs. 2 and 3. The camera 10 is pivotally supported on a camera column 12 erected from a base 11, and in a stationary state, the optical axis direction is held at a depression angle of 30 to 45 degrees. That is, the camera 10 is pivotally supported on the camera column 12 via links 15A and 15B, and the camera column side of the link 15 (15A, 15B) is the pivot point P and the camera side is the pivot point K. The camera 10 has a case 111, a camera body 110 held inside the case, a cable 118 for supplying power from a battery 30 to the camera body 110, an antenna 115 for wirelessly transmitting the captured image taken by the camera body 110, and a radio wave reflector 116 covering the antenna. And a schematic diagram 114 showing the field of view range is provided on the side surface of the case of this camera 10.

[0021] The camera body 110 is held in the case by a support pin 113. By this support pin 113, the camera body 110 can be rotated about a horizontal axis by about -5 degrees (depression angle) to 15 degrees in the elevation angle direction to fix the camera 10. That is, by this camera body tilting means, the optical axis direction of the camera body 110, which is held at a depression angle of 30 to 45 degrees in a stationary state, can be further adjusted by about -5 degrees to 15 degrees in the elevation angle direction. Thereby, the field of view of the camera 10 can be expanded.

[0022] The camera body 110 has a lens 110a and an LED light 110b. The lens 110a is preferably a wide-angle lens. For example, a wide-angle lens with a horizontal field of view of 45 degrees and a vertical field of view of 85 degrees (the longitudinal direction of the jib 3) can be used. The camera 10 for the jib crane is attached near the base end of the jib 3 as described above. The antenna 115 is preferably extended in the horizontal direction. And the antenna on the monitor side installed in the driver's cab 5 is preferably arranged to extend in the horizontal direction as well. Further, the antenna 115 is preferably covered by a radio wave reflector 116. With such a configuration, radio interference by the work building 6 can be reduced, and a good captured image can be obtained.

[0023] It is preferable that the crane operator knows in advance the extent of the visual field range of the camera 10. In the camera 10 of this example, a schematic diagram 114 is provided on the side surface of the case 111, showing the visual field range of the camera held at a depression angle with the optical axis direction of 30 to 45 degrees. Thereby, the crane operator can efficiently operate the jib crane. The battery 30 can be stored in a storage box and magnetically attached or / and tied with a binding band to the tip of the jib 3 or the telescopic boom 2 near the camera 10.

[0024] Figure 3 shows the configuration around the axial pivot point P of the camera 100 for this jib crane. The links 15 (15A, 15B) are pivotally supported on the camera support column 120 at the axial pivot point P at the upper part of the camera support column 12. In this example, a collar 123 is provided on the outer periphery of the camera support column 12, and the link 15 is supported on the camera support column 12 via the collar 123. Thereby, the link 15 is rotatably supported by the camera support column 12. The collar 123 is, for example, an aluminum pipe. Further, on the outer peripheral portion of the collar 123, a width-defining outer cylinder 124 is provided inside the links 15A, 15B, and retaining rings 126 (126A, 126B) are provided outside. The retaining rings 126 have their outer widths defined by split pins 25 (25A, 25B). The width-defining outer cylinder 124 and the retaining rings 126 can use, for example, plastic pipes. And a pressing ring 125 is provided between the retaining ring 126 and the link 15. The pressing ring 125 can use an elastic body such as rubber. If the end face of the retaining ring 126 is made into a shape that gradually tapers the diameter, the smaller the outer diameter of the pressing ring 125, the narrower the gap of the pressing ring portion becomes, so that the link 15 (15A, 15B) is more strongly pressed by the width-defining outer cylinder 124 and the retaining rings 126 (126A, 126B). By this pressing ring 125, the rotation around the axial pivot point P of the link 15 can be restricted, and the shake of the camera 10 can be corrected. That is, the pressing ring 125 functions as a deceleration member. The shake of the camera 10 can be appropriately adjusted by adjusting the thickness or the outer diameter of the pressing ring 125. Note that the deceleration member may be a friction ring having a so-called braking action.

[0025] The configuration around the axial pivot point K of the camera 100 for this jib crane can be made into a configuration similar to the configuration around the axial pivot point P. For example, as shown in FIG. 2, a case support shaft 16 composed of a collar 162 and a bolt 161 passing through it is provided at the axial pivot point K, and the case 111 is supported on the bolt 161 via the collar 162. Thereby, the camera 10 rotates freely around the axial pivot point K.

[0026] It is also possible to make the configuration around the shaft fulcrum K the same as the configuration around the shaft fulcrum P. In this case, the link 15 is removed, and the camera 10 is directly supported by the camera support column 12, which has the advantage of simplifying the configuration of the camera for the jib crane.

[0027] As described above, the camera 10 is held at a depression angle of 30 to 45 degrees in the optical axis direction in a stationary state. This is because the center of gravity of the camera 10 when the optical axis direction of the camera 10 is at a depression angle of 30 to 45 degrees coincides with the position of the shaft fulcrum K. For this reason, as shown in Fig. 2(a), the center of the camera support column 12, the center of the case support shaft 16, and the center of the support pin 113 are aligned in the vertical direction. In addition, when the camera body 110 is tilted to expand the field of view as described above, in order to secure the space, the shaft fulcrum K is selected to be as close as possible to the top surface of the case 111.

[0028] If the camera is supported by the shaft fulcrum K, the optical axis direction of the camera 10 will be at a depression angle of 30 to 45 degrees. For this reason, the camera 10 can be rotated (tilted) around the shaft fulcrum K with a small force, and the field of view range can be expanded. Fig. 4 shows an example of a camera tilting means using a chain. One end of the chain 20 is fixed to the case 110, and the other end is engaged with a pin 205 fixed to the camera support column 12. By adjusting the chain length according to the engagement position of the chain 20, the camera 10 can be rotated around the shaft fulcrum K. The front-side chain 20A of the camera 10 can rotate the camera 10 around the shaft fulcrum K in the elevation angle direction by 0 to 45 degrees, and the rear-side chain 20B can rotate the camera 10 in the elevation angle direction by 0 to -10 degrees. The chain 20 can be either one of the chains 20A or 20B, but when both the chains 20A and 20B are provided, the chain 20 functions as both a camera tilting means and an anti-vibration means. The chain 20 can be continuous or separated between the chains 20A and 20B. In addition, if a cable whose length can be controlled by a motor is used instead of the chain 20, the camera tilting means can be remotely operated.

[0029] The camera support column 12 can be made of a split type. In this case, it is possible to facilitate the attachment and detachment of the camera 10 to the jib 3, and the jib crane camera 100 can be used efficiently. An example of such a split type camera support column 12 is shown in Fig. 5. This camera support column 12 is composed of a base support column 120 erected on the base 11 and a camera support column main body 121 fitted thereto. The base support column 120 has a pin groove 120a and a pin hole 120b. The camera support column main body 121 has a pin hole 121b at the tip and a lock pin 121a in the middle part. First, when the camera support column main body 121 is inserted into the base support column 120, the lock pin 121a approaches the pin groove 120a, so the camera support column main body 121 is further inserted into the base support column 120 along the pin groove 120a with the lock pin 121a. When the lock pin 121a reaches the tip of the pin groove 120a, the pin hole 120b of the base support column 120 and the pin hole 121b of the camera support column main body 121 coincide (Fig. 5(b)). The pin part of the snap 24 with a pin is passed through the holes where the pin hole 120b and the pin hole 121b coincide. The base support column 120 and the camera support column main body 121 are fixed by the snap 24 with a pin. Note that the engagement relationship between the lock pin 121a and the pin groove 120a also functions as a safety device.

[0030] The base 11 has magnets 21 (21A, 21B), and the jib crane camera 100 can be firmly fixed to the jib 3. Commercially available neodymium magnets can be used as the magnets 21. Also, this base 11 can fix the jib crane camera 100 to the jib 3 by passing a binding band 23 through the band hole 11a provided in the base 11. Also, when the base 11 can be fixed to the jib 3 by welding, the magnets 21 and the binding band 23 can be removed.

Explanation of symbols

[0031] 1 Jib crane 2 Telescopic boom 3 Jib 4 Hook 5 Driver's cab 6 Work building 10 Camera 110 Camera body 111 case 113 support pin 114 schematic diagram 115 antenna 116 radio wave reflector 118 cable 11 base 12 camera support column 120 base support column 121 camera support column body 123 color 124 width-determining outer cylinder 125 pressing ring 126 retaining ring 15, 15A, 15B link 16 case support shaft 161 bolt 162 color 20, 20A, 20B chain 205 pin 21, 21A, 21B magnet 23 binding band 24 snap with pin 25, 25A, 25B split pin 30 battery 100 camera for jib crane

Claims

1. A camera for a jib crane that is attached to the lower part of the jib of the jib crane and wirelessly transmits an imaging image for assisting crane operation to a monitor installed in the cab, comprising a base fixed to the jib, a camera column erected on the base, and a camera pivotally supported on the camera column so as to be rotatable, wherein the camera is a camera for a jib crane whose optical axis direction is held at a depression angle of 30 to 45 degrees in a stationary state.

2. The camera is pivotally supported on the camera column at a shaft pivot point P at one end, and is pivotally supported on the camera column via a link that pivotally supports the camera at a shaft pivot point K at the other end, The jib crane camera according to claim 1, wherein a deceleration member for restricting the swing of the link is provided at the shaft pivot point P portion.

3. The camera for a jib crane according to claim 1 or 2, characterized in that the camera has a camera body tilting means for tilting the optical axis direction of the stationary state by about -5 degrees to 15 degrees in the elevation angle direction.

4. The camera for a jib crane according to claim 1 or 2, characterized in that the camera has a camera tilting means for tilting the optical axis direction of the stationary state by about -10 degrees to 45 degrees in the elevation angle direction.

5. The camera column has a base column fixed to the base and a camera column body detachably fitted to the base column, and the jib crane camera according to any one of claims 1 to 4.

6. The camera has a case, a camera body held in the case, a cable for supplying power from a battery to the camera body, an antenna for wirelessly transmitting an imaging image taken by the camera body, and a radio wave reflector covering the antenna, and a schematic diagram showing the visual field range is provided on the side surface of the case. The jib crane camera according to any one of claims 1 to 5.

Images