JPH0333748Y2 - - Google Patents

Description

[Detailed explanation of the idea]

(Field of Industrial Application) The present invention relates to a crane safety monitoring device that displays the safety level of lifting work. (Conventional technology) Cranes are at risk of tipping over when the actual load exceeds the rated load. In such cases, the crane is prohibited from operating in a dangerous direction. (Problem that the invention aims to solve) However, if the moment limiter is used to suddenly stop the crane, there will be dangers such as the load vibrating, so the operator will be able to detect in advance that a dangerous situation is approaching. It is desirable to move to the safe side before the moment limiter activates. In view of the above circumstances, the present invention provides a crane safety monitoring device that can display the degree of safety of lifting work according to the swing angle range of the boom. (Means for Solving the Problems) The present invention includes: a boom rotation angle detection means for detecting a rotation angle of a boom; a boom heave angle detection means for detecting a heave angle of the boom; and a boom length detection means for detecting a boom length. It has a boom length detection means for detecting the actual load, an actual load detection means for detecting the actual load, and a circular display area corresponding to the swing angle range of the boom, and this display area is divided into a plurality of angle ranges and those angles are displayed. a display device having a display element disposed in each of the areas, a turning position indicating means for indicating the turning position of the boom in the display area based on the output of the boom turning angle detecting means, and each of the divided angles. The rated load for each of the angle ranges is calculated from the storage means in which the boom hoisting angle and boom length are stored as parameters, and the outputs of the boom hoisting angle detection means and the boom length detection means. Read out the rated loads of the crane, compare those rated loads with the actual loads detected by the actual load detection means to determine the safety of the crane in each of the above angle ranges, and determine their degree of safety. It has a configuration including display control means for displaying the safety degrees on each of the display elements corresponding to the angle ranges. (Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a block diagram showing an embodiment of a safety monitoring device according to the present invention. In this embodiment, a boom swing angle sensor 1, a boom luffing angle sensor 2, and a boom length sensor 3 are provided to detect the swing angle, luffing angle, and length of the boom 22 of the truck crane 21 shown in FIG. A load sensor 4 is provided to detect the actual load (lifting load) of the crane. The output of sensor 1 is applied to motor control circuit 5, and the outputs of sensors 2, 3 and 4 are applied to display control circuit 6. The memory 7 stores the contents illustrated in Tables 1 and 2 below.

【table】

【table】

[Table] This type of crane has the swing angle range (θ ₁ + θ ₂ + θ ₃ ) shown in Figure 2, but due to its structure, the rated load and angle range θ in the angle ranges θ ₁ and θ ₃ The difference is that the former is smaller than the _latter . The memory contents of the memory 7 shown in Table 1 above are examples of the rated loads (in tons) for angle ranges θ ₁ and θ ₃ using the boom heave angle and boom length as parameters, and the memory contents shown in Table 2. exemplifies the rated load for the angle range θ ₂ using the above-mentioned boom luffing angle and boom length as parameters. The display 8 is connected to the boom 22 as shown in FIG.
A circular display panel 80 corresponding to a rotation angle range of
have. This panel 80 has the angle range θ ₁ ,
Divided into θ ₂ and θ ₃ , light emitting element arrays 81a to 81e are in the angular range _θ1 , light emitting element arrays 81f to 81h are in the angular range _θ2 , and light emitting element arrays 81i to 81i are in the angular range _θ3 . 81m are arranged radially. Each of the light emitting element arrays 81a to 81m is
It has a configuration in which a large number of light emitting elements 82 such as LEDs (seven in this embodiment) are arranged in a straight line, and among these light emitting elements 82, the first to third light emitting elements are A green light emitting element is used as the fourth element, yellow light emitting elements are used as the fourth and fifth elements, and red light emitting elements are used as the sixth and seventh elements. The pointer 9 shown in FIG. 3 is provided to indicate the turning position of the boom 22, and its base is connected to the panel 80 so that it can be rotated by the electric motor 10 (for example, a pulse motor) shown in FIG. It is supported at the center of the The operation of this embodiment will be explained below. The motor control circuit 5 drives the motor 10 based on the output of the sensor 1 so that the pointer 9 points in the direction in which the boom 22 turns. This allows the operator to know the turning direction of the boom 22 from the direction of the pointer 9. On the other hand, the display control circuit 6 operates as follows. The control circuit 6 executes a process of reading out the rated load corresponding to the current boom luffing angle and boom length from the memory 7 based on the outputs of the sensors 2 and 3. That is, among the rated loads for the angle ranges θ ₁ and θ ₃ shown in Table 1, the process of reading out the rated load W ₁ corresponding to the current boom heave angle and boom length;
Among the rated loads for the angle range θ ₂ shown in Table 2,
A process is executed to read the rated load W ₂ corresponding to the current boom luffing angle and boom length. Note that the rated loads W ₁ and W ₂ are actually obtained by interpolating the contents stored in the memory 7. Then, the ratio of the actual load W detected by the load sensor 4 to the rated loads W ₁ and W ₂ is calculated: m ₁ =W/W ₁ (%) m ₂ =W/W ₂ (%). Note that the ratios m ₁ and m ₂ indicate the safety degree of the crane in the angle ranges θ ₁ and θ ₃ and the angle range θ ₂ , respectively. The control circuit 6 controls each of the light emitting element arrays 81a to 81m of the display 8, for example, as follows based on the safety degrees _m1 and _m2 . (Light emitting element arrays 81a to 81e and 81j to
81m) a m ₁ <20%...The first to third green light emitting elements 82 all emit light. 20%≦m ₁ <40%...The first and second green light emitting elements 82 are made to emit light. 40%≦m ₁ <60%... Only the first green light emitting element 82 is made to emit light. 60%≦m ₁ <70%...The fourth yellow light emitting element 82 is made to emit light. 70%≦m ₁ <80%...The fourth and fifth yellow light emitting elements 82 are made to emit light. 80%≦m ₁ <90%...The sixth red light emitting element 82 is made to emit light. m ₁ ≧90%...The sixth and seventh red light emitting elements 82 are made to emit light. (Regarding the light emitting element arrays 81f to 81i) For the ratio _m2 , each light emitting element 82 is driven in the same procedure as above. Thus, according to this embodiment, it is possible to detect that the actual load is sufficiently smaller than the rated load from the light emitting state of the green light emitting element 82, and furthermore, it is possible to grasp the load margin from the number of light emitting elements of the green light emitting element 82. can. Further, it can be recognized from the light emitting state of the yellow light emitting element 82 that the actual load is relatively close to the rated load, and furthermore, it can be recognized from the light emitting state of the red light emitting element 82 that the actual load is extremely close to the rated load. Furthermore, since the pointer 9 indicates the turning position of the boom 22, it is extremely easy to determine whether or not it is safe to turn the boom from the angular range θ ₂ side to the angular range θ ₁ side, for example, from the content displayed on the display 8. And it can be known accurately. In the above embodiment, the angle ranges θ ₁ and θ ₃ are each 5
A light emitting element array is provided, and the angle range θ ₂ is 3
Although one light emitting element array is provided, it is sufficient for the display function to provide one light emitting element array in each angle range. That is, it is practically sufficient to provide only the array 81c in the angle range θ ₁ , only the array 81g in the angle range θ ₂ , and only the array 81k in the range θ ₃ . Further, when using the display device 8 shown in FIG. 3, each light emitting element array 8 as shown in FIG.
Angle ranges θ ₁ to _{θ 13} are set for each of 1a to 81 m, and rated loads for those angular ranges are set as shown in Tables 1 and 2 above, and each light emitting element is manufactured using this rated load. It is of course also possible to control the arrays independently. Furthermore, in the embodiment, the light emitting elements 82 of the light emitting element array have three different colors in order to enhance the display effect, but the point is that it is sufficient to display the degree of safety in each angle range. Each array may be constructed using only colored light emitting elements. Further, the display mode of the safety level is not limited to the above embodiment, and for example, the safety level may be displayed in the form of a bar graph using each of the arrays 81a to 81m. Furthermore, the light emitting element is not limited to LED,
Other display elements such as liquid crystal may also be applied. In the above embodiment, the pointer 9 is provided to indicate the turning position of the boom 22, but a large number of light emitting elements such as LEDs are arranged along the outer periphery of the panel 80, and a light emitting element corresponding to the position of the boom is arranged. The position of the boom may be displayed by emitting light. (Effect of the invention) According to the invention, the degree of safety for each swing angle range of the crane can be displayed while being compared with the position of the boom. Therefore, the operator can accurately sense the safety level of the current load lifting operation, thereby increasing the safety of the operation.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing one embodiment of the monitoring device according to the present invention, Fig. 2 is a plan view showing an example of a truck crane, and Figs. 3 and 4 each show the configuration of the display device. FIG. 5 is a plan view showing another example of the display device. DESCRIPTION OF SYMBOLS 1...Boom rotation angle sensor, 2...Boom elevation angle sensor, 3...Boom length sensor, 4...Load sensor, 5...Motor control circuit, 6...Display control circuit, 7...Memory, 8... ...Display device, 80... Panel, 81a to 81m... Light emitting element array, 9...
Pointer, 10... electric motor, 21... truck crane, 22... boom.

Claims (1)

[Claims for Utility Model Registration] Boom rotation angle detection means for detecting the rotation angle of a boom; boom heave angle detection means for detecting the heave angle of the boom; boom length detection means for detecting the length of the boom; , an actual load detection means for detecting an actual load, and a circular display area corresponding to the swing angle range of the boom, and the circular display area is arranged corresponding to each fan-shaped angle range of the swing angle range. a display device that is divided into each angle range and has a display element arranged in each angle range of the circular display area; and a display device that determines the rotation position of the boom in the circular display area based on the output of the boom rotation angle detection means; a slewing position indicating means for instructing the slewing position; a storage means storing the rated load for each angle range of the swiveling angle range using the boom's luffing angle and length as parameters; the boom luffing angle detecting means and the boom length; Based on each output of the detection means, the rated loads for each angular region of the turning angle range are read from the storage means, and each of these rated loads and the actual load detected by the actual load detection means is calculated. Determine the ratio as the safety degree for each angle range of the turning angle range,
A safety device for a crane, comprising display control means for displaying the degree of safety for each angle range on a display element for each angle range of the circular display area.