JP5468430B2 - Work gondola fall prevention mechanism - Google Patents

Description

  The present invention appropriately detects that the wire rope is entangled with the safety rope for preventing the work gondola from dropping even when the work gondola is suspended and operated using the wire rope of the mobile crane that can freely travel. The present invention relates to a mechanism for preventing a work gondola from falling.

  In order to prevent the work gondola suspended by the rope from being lifted and lowered, in addition to the rope that suspends the work gondola, as a work gondola fall prevention mechanism equipped with a fall prevention rope, Patent Document 1 is known.

  The “working gondola” disclosed in Patent Document 1 includes a pair of gondola support arms that are spaced apart from each other by a predetermined distance from a housing, such as both ends of a roof of a building, and fixed so that the front end protrudes outward from the building. The pair of ropes hung from the end portions of the pair of gondola support arms, respectively, and the pair of ropes can be used to perform a cleaning operation such as a window glass on which a person rides. A working gondola body having a width dimension smaller than the dimension between the pair of gondola support arms, and a pair of rope telescopic devices fixed to the roof of the building or the working gondola body for expanding and contracting the pair of ropes, respectively; The housing in the vicinity of the pair of gondola support arms or the tip fixed to the work gondola main body is a work gondola or a pair of gondola support A pair of lifeline winding devices each winding a lifeline attached to a frame or a nearby body, and when the lifeline winding shaft of the pair of lifeline winding devices rotates rapidly, the lifeline winding is caused by the action of centrifugal force. It comprises a pair of locking devices that stop the rotation of the take-up shaft.

Utility Model Registration No. 2517228

  In addition to ropes that operate the gondola for working, etc., when using ropes for fall prevention such as lifeline separately as in the background art, there is a risk that these ropes may be entangled with each other. When a work gondola is suspended from a wire rope of a crane type crane and operated, there is a high possibility that the wire rope of the crane will be entangled with a rope for preventing the fall, and an improvement has been desired.

  The present invention was devised in view of the above-described conventional problems, and the wire rope can be operated even when the work gondola is suspended and operated using the wire rope of the mobile crane that can run freely. It is an object of the present invention to provide a work gondola fall prevention mechanism capable of appropriately preventing the safety gondola from being entangled with the safety rope for fall prevention.

The working gondola fall prevention mechanism according to the present invention is a working gondola that is drawn up and wound by a main winch mounted on a movable mobile crane, and is hung up and down by a wire rope stretched over a sheave. A fall prevention mechanism for the mobile crane, the auxiliary winch mounted on the mobile crane in front of the main winch, and independent of the wire rope and always positioned in front of the wire rope. wound around the secondary winch via pulleys provided on the boom of the mobile crane is connected to the gondola for the work by the auxiliary winch, in correspondence with the lift of the gondola for the work, the feeding winding can in, and a safety rope to slowly mooring the gondola for the work remembering slack, to detect the feeding speed of the safety rope, decremental When the speed is the set speed or more, the stop signal for stopping the feeding of the safety rope is characterized in that a feeding speed detecting device for outputting to the auxiliary winch.

In the work gondola fall prevention mechanism according to the present invention, even when the work gondola is suspended and operated by using the wire rope of a mobile crane that can run freely, the wire rope is the work gondola. It is possible to appropriately prevent tangling with the safety rope. More specifically, in a mobile crane, a subordinate that operates a safety rope that is connected to and moored with a work gondola is positioned in front of a main winch that operates a wire rope that suspends a work gondola so that it can be raised and lowered. Even if a winch is installed, a safety rope is always positioned in front of the wire rope, and the work gondola is suspended and operated using the wire rope of a mobile crane that can run freely, the wire rope Can be properly prevented from being entangled with the safety rope, and the work gondola can be reliably prevented from falling. In addition, the safety rope is operated by the auxiliary winch separately from the main winch and also separately from the wire rope, so that the safety rope is wound up when the work gondola is lifted and before the lowering operation when it is lowered. It is possible to cope with the raising and lowering of the work gondola by simply extending the safety rope in advance and loosening the safety rope to gently moor the work gondola. The drive of the main winch and sub winch is linked. In this case, the control complexity can be avoided, and the configuration of the fall prevention mechanism can be simplified. In addition, the work gondola can be safely suspended by operating the auxiliary winch independently. Therefore, when the main winch breaks down, the safety gondola can be hung by operating the safety rope with the auxiliary winch.

It is a side view which shows suitable one Embodiment of the fall prevention mechanism of the work gondola which concerns on this invention. It is a principal part enlarged view of FIG.

  Hereinafter, a preferred embodiment of a working gondola fall prevention mechanism according to the present invention will be described in detail with reference to the accompanying drawings. FIGS. 1 and 2 show a case in which a chimney 3 is repaired by suspending a work gondola 2 so that it can be raised and lowered with a mobile crane 1.

  Various types of mobile cranes 1 are well known, and for example, the mobile crane 1 is self-propelled so as to be able to run freely with an installed engine. As is well known, the mobile crane 1 is equipped with a lifting boom 4 that is turned and tilted by various methods such as a wire driving method and a cylinder driving method. In the illustrated example, a crawler crane equipped with a lattice boom is used as the mobile crane 1.

  The mobile crane 1 is equipped with a main winch 5 that is rotationally driven by a motor or the like as a lifting equipment, and a wire rope 6 that is drawn out and wound up by forward / reverse rotation operation of the main winch 5 (see FIG. 2). ). The wire rope 6 wound on the base winch 5 at the base end side is stretched to the tip of the boom 4 through sheaves arranged at various locations on the boom 4. A locking tool 7 such as a hook for locking an object is attached.

  In the mobile crane 1, the boom 4 that protrudes forward is usually mounted on the front side so that the lifting work can be easily performed, and the mounting position of the main winch 5 is set so that the mobile crane 1 does not fall during lifting. , Set to the rear side.

  When various operations are performed at a high place by the work gondola 2, the work gondola 2 is locked to the locking tool 7 at the tip of the wire rope 6, and the boom 4 is turned and the wire rope 6 is extended by the main winch 5. It is suspended at an appropriate position by the lifting operation by winding.

  In the present embodiment, the auxiliary crane 8 is mounted on the mobile crane 1 so as to be positioned in front of the main winch 5. In the illustrated example, the auxiliary winch 8 is mounted in front of the mounting position of the boom 4 to the mobile crane 1. However, the auxiliary winch 8 may be mounted on the rear side of the mounting position of the boom 4 as long as the auxiliary winch 8 does not interfere with the boom 4 to be turned and tilted.

  The auxiliary winch 8 can be rotated forward and backward independently of the main winch 5 by a motor or the like provided therein.

  A safety rope 9 is wound around the auxiliary winch 8 separately from the wire rope 6. The safety rope 9, whose proximal end is wound around the secondary winch 8, is connected to the work gondola 2 via a pulley 10 provided at the distal end of the boom 4, and the work gondola 2 is connected to the secondary winch 8. Moored slowly.

  Specifically, the work gondola 2 is suspended by a wire rope 6, and a safety rope 9 is connected to the suspended work gondola 2. Therefore, the safety rope 9 may have some slack. In the illustrated example, the tip of the safety rope 9 is connected to the locking tool 7 and is indirectly connected to the work gondola 2 via the locking tool 7. However, the safety rope 9 may be directly connected to the work gondola 2 without using the locking tool 7.

  In addition to the operation of the wire rope 6 by the main winch 5, the safety rope 9 is fed out and wound up by the auxiliary winch 8 in association with the raising and lowering of the work gondola 2. Specifically, for example, when the working gondola 2 is lifted with the main winch 5, the safety rope 9 is wound up by the auxiliary winch 8 after the lifting operation. When the work gondola 2 is lowered with the main winch 5, the safety rope 9 is extended by the auxiliary winch 8 with a margin before the lowering operation. In this way, the safety rope 9 is fed out and wound up by the auxiliary winch 8 in association with the raising and lowering of the work gondola 2.

  In the mobile crane 1, the main winch 5 that handles the wire rope 6 is mounted on the rear side, and the auxiliary winch 8 that handles the safety rope 9 is mounted on the front side, so that the mobile crane 1 travels and turns. The safety rope 9 is always positioned in front of the wire rope 6.

  The mobile crane 1 is provided with a feeding speed detection device 11 that detects the feeding speed of the safety rope 9. The feeding speed detection device 11 is configured to include, for example, a rotary encoder, and detects the feeding speed of the safety rope 9 from the rotational displacement of a rotating plate or the like that rotates in frictional contact with the rotating shaft of the auxiliary winch 8 or the safety rope 9. It has become. The feeding speed detection device 11 is connected to the auxiliary winch 8.

  The feeding speed detection device 11 outputs a stop signal s for stopping the feeding of the safety rope 9 to the sub winch 8 when the feeding speed of the safety rope 9 to be fed is equal to or higher than a preset speed, and the sub winch 8 The feeding of the safety rope 9 is stopped according to the stop signal s.

  Next, the operation of the working gondola fall prevention mechanism according to this embodiment will be described. When working with the work gondola 2, the work gondola 2 is locked to the locking tool 7 and the boom 4 is raised to a predetermined position, while the wire rope 6 is unwound from the main winch 5 behind the mobile crane 1 and moved. A safety rope 9 is fed out from the auxiliary winch 8 in front of the crane 1. After the boom 4 is stopped, the wire rope 6 is unwound and wound by the main winch 5 to raise and lower the work gondola 2, and the work gondola 2 is suspended to a predetermined position by the wire rope 6 and stopped.

  At this time, the safety rope 9 is unwound and wound up by the auxiliary winch 8 in association with the raising and lowering of the work gondola 2, and the safety rope 9 is gently passed between the locking tool 7 and the auxiliary winch 8, The work gondola 2 is moored by the rope 9. Thereby, various work can be performed using the work gondola 2.

  On the other hand, when the work gondola 2 is suspended by the wire rope 6 or when the work gondola 2 is moved up and down, the work gondola 2 falls due to breakage of the wire rope 6, failure of the main winch 5, or other reasons. When this occurs, the weight of the work gondola 2 is transferred to the safety rope 9 connected to the work gondola 2. When the weight of the work gondola 2 changes, the safety rope 9 is suddenly drawn out from the auxiliary winch 8.

  The feeding speed detection device 11 that detects the feeding speed of the safety rope 9 outputs a stop signal s to the auxiliary winch 8 when detecting that the safety rope 9 is suddenly fed, that is, that the feeding speed is equal to or higher than the set speed. The auxiliary winch 8 to which the stop signal s is input stops the feeding of the safety rope 9, thereby suspending the work gondola 2 with the safety rope 9 and preventing its fall.

  Thereafter, the work gondola 2 is slowly suspended from the ground by operating the auxiliary winch 8 and feeding the safety rope 9 out.

  As described above, in the work gondola fall prevention mechanism according to the present embodiment, in the mobile crane 1, rather than the main winch 5 that operates the wire rope 6 that suspends the work gondola 2 so as to be lifted and lowered. Since the auxiliary winch 8 for operating the safety rope 9 connected to the work gondola 2 and mooring it is mounted in the front, the safety rope 9 is always positioned in front of the wire rope 6. Even when the work gondola 2 is suspended and operated using the wire rope 6 of the mobile crane 1 that can travel freely, the wire rope 6 is appropriately prevented from being entangled with the safety rope 9. It is possible to prevent the work gondola 2 from dropping.

  Further, since the safety rope 9 is operated separately from the main winch 5 and by the auxiliary winch 8 alone, the safety rope 9 is wound up after being lifted when the work gondola 2 is lifted, and before the lowering operation when being lowered. It is possible to correspond to the raising and lowering of the work gondola 2 by a simple operation of extending the safety rope 9 in advance, and it is possible to avoid the complexity of control when the driving of the main winch 5 and the auxiliary winch 8 are linked, and to prevent the fall. The structure of the mechanism can be simplified. In addition, the work gondola 2 can be safely suspended by operating the auxiliary winch 8 independently. Therefore, even when the main winch 5 breaks down, the safety rope 9 can be operated by the auxiliary winch 8 to suspend the work gondola 2.

  In addition, since the feeding speed detecting device 11 capable of detecting that the feeding speed of the safety rope 9 is equal to or higher than the set speed is provided to control the auxiliary winch 8, the suspension function of the main winch 5 and the wire rope 6 is provided. When lost, the work gondola 2 can be suspended by the safety rope 9 immediately, and the work gondola 2 can be reliably prevented from falling.

DESCRIPTION OF SYMBOLS 1 Mobile crane 2 Working gondola 4 Boom 5 Main winch 6 Wire rope 8 Sub winch 9 Safety rope 10 Pulley 11 Feeding speed detection device

Claims (1)

A work gondola fall prevention mechanism that is drawn up and wound up by a main winch mounted on a mobile crane that can run freely, and is suspended by a wire rope stretched over a sheave so as to be lifted and lowered.
A sub winch mounted on the mobile crane in front of the main winch, and separately from the wire rope, is always positioned in front of the wire rope and is wound around the sub winch, is connected via a pulley provided on the boom of the mobile crane to the gondola for the work by the auxiliary winch, in correspondence with the lift of the gondola for the work, the feeding winding possible, the work imparted loosening A safety rope for gently mooring the gondola, and a feeding speed that detects a feeding speed of the safety rope and outputs a stop signal to the auxiliary winch to stop the feeding of the safety rope when the feeding speed is equal to or higher than a set speed. A working gondola fall prevention mechanism comprising a speed detection device.

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