CN2043615U - Safety brake for gantry elevating platform - Google Patents

Abstract

Disclosed is a safety brake for gantry elevating platforms which is a safety brake device. The utility model is suitable for various hoist cranes of the gantry frame elevating platform. When unexpected accidents appear (the braking distortion of the hoist crane, the sudden stretch breaking of the wire rope, etc.), the safety installed at the upper beam of the elevating platform of the crane prevents the elevating platform from sliding by a series of mechanical motion of the retainer, the clamping mechanism and embracing cam under the condition of suddenly disappearing wire rope pulling, and avoids economy loss and personal casualty.

Description

Safety brake for gantry elevating platform

The utility model is a kind of automatic safe brake equipment, and it is applicable to various winding type portal frame lifting table hoisting cranes and similarly mechanical on the building ground.

In China's construction trade, up to the present the employed on-site gantry frame type lifting table hoisting crane that is used for transporting various building materialss, does not also have good safety catch.In most of the cases, trouble free service just guarantees by the brake of winch.Once brake failure or steel rope are broken suddenly, then lifting table will out of controlly glide, thereby causes economic loss so that personnel casualty accidents.This also happens occasionally on China's construction trade history in the past.

The purpose of this utility model is exactly that a kind of automatic safety catch will be provided for above-mentioned gantry frame type hoisting crane, and it is installed on the upper beam of lifting table.When the brake failure of winch or steel rope were broken, it can automatically prevent lifting table because the out-of-control phenomenon of the rapid landing of action of gravity takes place, thereby avoids loss and personal casualty.

The concrete structure of utility model and principle of work can explain detailedly referring to accompanying drawing.

Fig. 1 is the scheme of installation of portal frame lifting platform safety device.

Fig. 2 is the major part one limiting device constructional drawing of safety.

Fig. 3 is the constructional drawing of another major part-clamping mechanism of safety.

Fig. 4 holds cam face figure tightly for safety.

Referring to Fig. 1 fixed pulley (4) is installed above portal frame, has below movable pulley (7) to be installed on the movable pulley frame (22). Two cover clamping mechanism symmetries are installed on the upper beam of hoistable platform centered by stop. That thick walled steel tube with loam cake is welded on above the base plate (21) referring to the inner sleeve (1) of Fig. 2 limiter. The overcoat of stop (2) also is that thick walled steel tube is welded on the upper plate (8). Gag lever post (3) is the tap bolt that a diameter is approximately 40-45. Pass the hole that covers on the inner sleeve (1) and be fixed together with nut and upper plate (8) and movable pulley frame (22), and between gag lever post (3) and the inner sleeve (1) relative displacement is arranged. Tie rod (9) is fixed on the upper plate (8), and the lower end connects with conduction chain (10) with pin. After chain (10) is walked around gipsy sheave (15) and is turned to 90 ° with base plate (18) keeping parallelism position. The gipsy sheave of trough of belt (15) is fixed on the base plate (18) by gipsy sheave frame (20). The other end of conduction chain (10) connects with pull bar (14). Referring to Fig. 3, pass square opening on the fixing saddle (17) with the pull bar (14) of spring (16), with four connecting rods (13) mounted thereto, half pliers (12) with both sides has consisted of two parallel four-bar linkages again. On two and half pliers (12), be fixed with baffle plate (23), to prevent its stressed rear flexural deformation. Respectively be equipped with one and hold cam (11) tightly on the termination of two and half pliers (12), cam (11) keeps clamped condition with portal frame principal post (6) when hoistable platform is slack. At this moment the short radius edge of cam (11) contacts with gantry pillar (6).

When steel wire rope of windlass (5) when being tightened up, because movable pulley (7), movable pulley frame (22), be rigid attachment between stop overcoat (2) and the gag lever post (3), thereby begin together to rise, meanwhile by tie rod (9), chain (10) pull bar (14) on stop both sides is strained, spring (16) begins compression, again because connecting rod (13), parallel four-bar linkage between pull bar (14) and half pliers (12), therefore half pliers (12) opens, and this moment, the former cam (11) that is in clamped condition was thrown off with gantry pillar (6). When the lower end of gag lever post (3) contacted with the loam cake of inner sleeve (1), the relative displacement between the parts of mechanism stopped, and all parts keep relative static conditions, thereby play position-limiting action. At this moment hoistable platform (19) begins to rise, until hoist engine stops traction.

When lifting table (19) requires, only need slowly to loosen steel rope and get final product by winch, still keep balance between steel rope and the bay-lift, half pliers still opens, and bay-lift can descend steadily.If it is too fast that steel rope is put, to such an extent as to the falling speed of bay-lift during near free-fall velocity, lack of equilibrium between steel rope and the bay-lift, half pliers begins to clamp gantry pillar, makes the bay-lift stop motion.If slowly loosen behind the retighten this moment steel rope, bay-lift can descend from average rate again, falls earthward also can not produce impact.

In the process that lifting table is rising or descending, the winch Control Failure takes place, or steel rope is when phenomenon such as breaking, because steel rope disappears to the pulling force of lifting table, at this moment, limiting device overcoat (2), position-limited lever (3), spring (16) etc. reset rapidly, impel half pliers to clamp gantry pillar rapidly, friction force between them on the contact surface makes cam begin to rotate, when the gripping power between cam and the gantry pillar is enough big, make bay-lift stop automatically descending, almost stop on the position when meeting accident.

If in bay-lift decline process, below catching sight of dangerous situation is arranged, in the time of need stopping to descend immediately,, bay-lift be stopped at once as long as winch loosens steel rope suddenly, prevent the generation of anything unexpected accident.

From the working condition of this device under above-mentioned several situations, we have seen its safety guard-safeguard effect, and meanwhile this device also has following advantage:

1. because limiting device is housed,, thereby the life-span of mechanism and the accuracy of work have been guaranteed so under different load, the first transaction of a day's business size of the limit of length of spring compressed and half pliers is constant.

2. because the mobility on one side of this mechanism is one, so half pliers can self-locking, operation pressure 60 kgfs (Kgf) as the employing spring also can normally move when zero load.

3. cam itself has the characteristics of reducing, thus after beginning to clamp, also have certain clamping leeway, thus can obtain approaching the gripping power of ∞, thus the safety of bay-lift failure-free guaranteed.

4. formed by the steel pipe post that two triangles are placed mostly because of present China employed portal frame in building site, (in-line column or single column are also arranged), generally be separated by and be welded with lacing wire between the 500-600mm at its axis direction, and the gripping power of this device is distributed in four above the cam, therefore unlikely gantry pillar generation flexural deformation or the undue elastic deformation of causing so just guaranteed the normal use of portal frame.

5. because this system has the adaptability to changes of each side, even operate lack of standardizationly, it also can make safe and reliable reflection, therefore can be used for transporting the object that operating personal and any fearness are impacted fully.

The utility model safety is rational in infrastructure, installs simply, and reliable in action not only can be used for building on the portal frame hoisting crane in symbol building site, and other that can be used for also that other occasions such as factory, restaurant adopt gantry frame type lifting liftings are above the equipment.

Claims (3)

1, portal frame lifting platform safety device is a kind of safety catch, is applicable to the winding type hoisting crane.What it adopted is fixed, movable pulley mechanism.It is characterized in that: its sure brake system is by limiting device.Clamping mechanism and hold cam tightly and form.By the mechanical movement of a system, make lifting table in the course of the work, can play the safety guard-safeguard effect automatically for the anything unexpected phenomenon that is taken place.

2, according to the safety of claim 1, the limiting device that it is characterized in that it be by on cover porose and be fixed on interior cover (1) on the lower shoe (21), the position-limited lever (3) that the termination is arranged at overcoat (2) that is fixed together with upper plate (8) and bottom is formed.Position-limited lever (3) passes the hole of interior cover (1) loam cake, be fixed together and relative displacement is arranged between position-limited lever (3) and the interior cover (1) with screw and movable pulley frame (22) and upper plate (8), but when the lower end of position-limited lever (3) contacts with the loam cake of interior cover (1), displacement stops, thereby plays spacing effect.

3, according to claim 1,2 safety, it is characterized in that: its clamping mechanism is the pull bar (14) that is with spring (6) by top, two parallel four-bar linkages that four connecting rods (13) and half pliers (12) constitute are formed, and on two terminations of half pliers (12), also be equipped with and hold cam (11) tightly, when the spring force above the pull bar (14) suddenly disappears, because the effect of four-bar linkage, half pliers (12) closes up, clamp gantry pillar (6) by cam (11), and because its friction force that clamps on the contact surface rotates cam (11), make its gripping power reach maximum, thereby guarantee the lifting table stop motion, automatically play the safety arrestment effect.

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