JPS61126441A - Measuring device for load of elevating device for sea working table - Google Patents

Abstract

PURPOSE:To measure an accurate load by a simple device by detecting a turning force generated as a reaction force at the main body of the 1st speed reducer composed of a planetary gear mechanism and measuring torque which operates on a pinion. CONSTITUTION:The elevating device J for the working table body 1 consists of the 1st speed reducer 5 which reduces the turning force of a motor 4 through the planetary gear mechanism, the 2nd speed reducer 6 which further reduces the rotation, and the pinion 8 which engages a rack 8. Then, load converters 15 and 15' are provided to tip parts of arm bodies 13 and 13' of the 1st speed reducer 5. Then, when torque is transmitted from the output shaft of the 1st speed reducer 5 to the pinion 7 engaging the rack 8, the turning force as the reaction force is generated at the main body of the 1st speed reducer 5 and transmitted to the load converters 15 and 15', so the force suitable to the torque is changed into resistance variation to calculate and display a load which operates on tooth surfaces of the pinion 7.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a load measuring device for a lifting device on an offshore work platform;
More specifically, the load on the lifting device on an offshore work platform equipped with a so-called rack-and-pinion lifting device in which the rack provided on the leg and the pinion of the lifting device installed on the work platform are engaged. This relates to a measuring device.

[Prior art]

In a rack-and-pinion offshore workbench, a drive machine (motor) drives a pinion provided at the output end of the secondary reducer via the primary and secondary reducers.
The workbench body is configured to be raised and lowered relative to the legs provided with racks by rotation of this pinion.

When moving the offshore work platform, the legs are made to protrude above the main body of the work platform, the legs are lowered at a predetermined location, and when the lower end of the legs touches the seabed, the main body of the work platform is moved. It is raised to a predetermined height above sea level and maintained in a predetermined working condition.

By the way, in such offshore work platforms, it is necessary to measure the load, that is, the magnitude of torque, generated on the pinion from the viewpoint of work safety. The capacity of this type of lifting device is determined based on the magnitude of the load acting on the pinion, but in this case, due to economic considerations, the standard value is higher than the load that occurs in normal use. A slightly larger value is set.

Therefore, if sea conditions such as wind and waves become severe and the pinion generates a torque that exceeds its designed lifting and lowering capacity, there is a risk that the lifting device will be damaged and, in some cases, the offshore work platform will topple over.

In order to prevent this risk, it is necessary to measure the load generated on the pinion, and when this load exceeds an allowable value, the work platform must be lowered, landed in the water, and evacuated to a safe area. The load on each pinion must be maintained at all times regardless of whether the lifting device is in operation or stopped.
Subsequently, no lifting device was equipped with a location or method for accurately measuring the load.

[Object of the Invention] The present invention was made in view of the above-mentioned drawbacks in the conventional elevating type offshore work platforms, and the present invention focuses on the characteristics of the planetary gear reducer that is the first reducer, that is, the main body (internal gear The purpose of this invention is to provide a device that is simple and inexpensive and can accurately measure loads by utilizing the torque generated in gears.

[Summary of the invention]

To achieve the above object, the present invention provides a marine work platform in which a rack provided on a leg and a pinion of an elevating device provided on a work platform main body are engaged with each other, wherein the elevating device is a planetary gear. The speed is reduced by a first speed reducer using a mechanism and a second speed reducer, and the pinion provided on the output shaft of the second speed reducer meshes with the rack, and a reaction force is generated in the main body of the first speed reducer. The counter torque of the pinion is measured using rotational force, this is extracted as a signal, this signal is amplified, and then arithmetic processing is performed and displayed as an analog/digital signal.

〔Example〕

Next, the present invention will be described in detail with reference to the drawings.

The offshore workbench is composed of a workbench main body 1 and legs 2 that pass through the main body 1 in the vertical direction, and a lifting device J is installed on the deck of the workbench main body 1 (or between the upper deck and the lower deck).
is provided.

The leg body 2 is configured in a tower shape by connecting three to four cords (metal tubes) with horizontal beams or diagonal beams.
The figure shows a state in which a pinion 7 provided on an output shaft of an elevating device J is opposed to and meshed with a pinion 7 provided on both sides of one cord constituting the leg body 2.

As shown in FIGS. 1 and 2, the lifting device J transmits the rotational force of a motor 4 having a brake 3 to a first speed reducer 5 that decelerates the speed using a planetary gear mechanism, and transmits the reduced rotation to a second speed reducer. The second speed reducer 6 further decelerates the speed and drives a pinion 7 provided on the output shaft of the second speed reducer 6. This pinion 7 meshes with racks 8 provided on both sides of the cod that constitutes the leg 2, and the workbench main body 1 is raised and lowered along the leg 2 with the rotational force of this pinion 7. is configured to do so.

3 and 4 show the first reducer 5, which is composed of a planetary gear mechanism and is mounted on a support base 11 fixed to the frame 8 of the lifting device via a bearing 12. The main body of the first reduction gear 5 (incorporating an internal gear) is rotatably supported in the direction of the torque generated.

An arm body (torque arm) 13.13° extends from the side of the main body of the first reducer 5, and a support portion 14, 14° protruding above the support base 11 further extends the arm body 13 ,13'
is supported.

A load transducer 15.15' using a strain gauge is provided at the tip of the arm body 13.13°, and the rack 8
The output shaft 1 of the first decelerator 5 with respect to the pinion 7 meshing with the
6, the torque generates a rotational force in the main body of the first decelerator 5 as a reaction force of the torque, and the arm body 13 provided on the main body is rotated. or 13' (depending on the direction of rotation of the pinion) forces are transmitted to the load converter 15 or 15' (Fig. 5, depending on the direction of rotation of the pinion).

The force corresponding to the magnitude of the torque is replaced with a resistance change and converted into an electrical quantity, and this is amplified to convert the rotational force of the main body (internal gear) of the first reduction gear H5 to the pinion 7 using analog or digital instructions. It is configured to calculate and display the load acting on the tooth surface.

When the offshore workbench is working (in a stationary state), the brake 3 attached to the motor 4 is activated to fix the workbench main body 1 to the legs 2. Even in this case, the pinion 7 is Since the torque for reversing the gear is generated in the main body of the first reduction gear 5 through the transmission, this torque can be measured and displayed as described above.

More specifically, in the load measuring device configured as described above, the load (f) on the output shaft 16 of the first reducer 5 due to the counter torque (T) of the pinion 7 is equal to 5
If the distance (β) and (7!”) from the axis of the output shaft 16 to the load application point of the load converter are the radius, then the load F acting on the load converter is: F=f/n and F A load (F) having a value of =f/I2' is applied to these two arm bodies 13° and 13°, respectively, when the shoulder lowering device J moves up and down.

Therefore, the counter torque (T) acting on this arm body 13.13'
As shown in Fig. 5, the load (F) caused by
) is converted into an electrical signal to extract a signal (S), which is amplified by an amplifier 20 and further led to an arithmetic processor 21 for arithmetic processing. The data from this arithmetic processor 21 can be printed out using an analog/digital display 22 or a printer 23.

〔Effect of the invention〕

The load measuring device for a marine workbench according to the present invention measures the rotational speed of the motor 4 using a first reducer 5 made of a planetary gear mechanism and a second reducer 6 that further reduces the rotation of the first reducer 5. The pinion 7 which is the output end of this second reducer 6 decelerates.
In a device that raises and lowers the workbench body 1 with respect to the legs 2 by driving the pinion 7, the torque itself generated as a reaction force on the body of the first N-speed machine 5 is replaced with a load (F) and measured. It is configured to measure the torque acting on the

Therefore, while the motor 4 is driving, the workbench main body 1
It is possible to measure the load acting on the pinion 7 while the leg 2 is at rest in a predetermined position.

As described above, the load measuring device according to the present invention measures the torque generated in the main body of the first reducer 5 made of a planetary gear mechanism, that is, the internal gear, by the rotational force of this main body. It is sufficient to support the reducer 5 in a slightly floating state, and the structure is extremely simple, and the main body itself does not move appreciably, making it possible to accurately measure the load on the pinion.

As described above, according to the load measuring device of the present invention, it is possible to measure the load accurately and quickly, so it is possible to immediately respond to emergencies, and it is possible to use the offshore work platform within the allowable design load, which was unprecedented. By providing a monitoring device that enables this, it is possible to further improve the safety of offshore work platforms.

Note that the present invention can be used in a lifting device that uses a speed reducer having a planetary gear mechanism as a speed reduction means, so the present invention can be easily applied to conventional devices.

[Brief explanation of drawings]

Fig. 1 is a front view showing a rack-and-pinion type elevating device for an offshore work platform, Fig. 2 is a left side view of the same, and Fig. 3 is a side view of the first reducer which is the primary reduction means of the elevating device. FIG. 4 is a front view of the same, and FIG. 5 is a flowchart showing a method of operating the load measuring device according to the present invention. DESCRIPTION OF SYMBOLS 1... Workbench main body, 2... Leg body, 3... Brake, 4... Motor, 5... First reducer, 6... Second
Reducer, 7...pinion, 8...rack, A...
Support part, 11... Support stand, 12... Bearing, 13.13°... Arm body (torque arm), 14.14
'...Support part, 15.15°...Load transducer, 20...Amplifier, 2
1... Arithmetic processor, 22... Analog/digital display, 23... Printer.

Claims (1)

[Claims] In a marine work platform in which a rack provided on the legs is engaged with a pinion at the output end of a lifting device provided on the work platform main body, and the work platform main body is raised and lowered with respect to the legs, the lifting device has a motor. It has a first reduction gear made of a planetary gear mechanism driven by a planetary gear mechanism, and a second reduction gear that further reduces the rotation of the first reduction gear, and the pinion is fixed to the output shaft of the second reduction gear. , the main body of the first reduction gear is supported on a support base so as to be rotatable in the direction of torque, and the rotational force of the main body is detected to measure the torque acting on the pinion. Load measuring device for work platform lifting equipment.