CN1063466A - Load lifting limiter - Google Patents

Abstract

A kind of load lifting limiter, it is an independently single unit system, be hinged under the trolley frame or the fixed pulley group of jib upper end near, with raising line branch by the arbitrary pulley in this assembly pulley, its pulley system of pile warp is converted to horizontal pressure with the pulling force of restricting, and passes to the spring damping cylinder with master cock, when overload, promptly can cut off the power supply.The level that its lift heavy signal conversion is transmitted is few, have damping and support equilibrium activity, reduced the error that causes by component assembly and inertia impact, compact conformation, oad is little, be easy to adjust and demarcate, have extensive applicability, can be as the annex of complete machine, with polytype hoisting crane, crane in bridge type particularly, supporting uses such as transfer crane or handling bridge.

Description

Load lifting limiter

The present invention relates to a kind of load lifting limiter of hoisting crane.

Load lifting limiter is divided into electron type and mechanical type device.The mechanical type device generally adopts the spring travel of reflection lift heavy signal, makes the electric controling switch action, with cut-out lifting mechanism power supply, and shows alarm signal.The spring that rigidity is bigger, influenced not quite by the lift heavy inertia impact, enough part strength, it and the electron type device that adopts sensor and electronics system to form are compared, the stable type that is showing, the reliability of action and the durability aspect of use more adapt to the service condition and the environment for use of hoisting crane.

But existing mechanical type device, conversion transmission to the lift heavy signal utilizes pulley lever system or pulley system more, raising line pulling force with reflection lift heavy signal, be converted into pressure to spring, structurally can not form independently whole, all will with the fixed pulley on the hoisting crane, assembly relation takes place in equalizer pulley, leading sheave etc., often cause the particular difficulty on installing and adjusting, its contour structure size, non-warp are totally considered, are difficult to find the position and the space that can hold on general hoisting crane, greatly reduce its applicability, at present, only limit to be applied on the hoisting crane that lifting mechanism is the simply connected assembly pulley, on some movable arm type formula hoisting crane.

No. 1393771, Russian Patent, the equalizer pulley of reflection lift heavy signal is installed on the double-arm lever that dead axle rotates, balance by means of stretching and compression spring, make it be in quick condition, when overload, the deflection of spring makes the double-arm lever revolution, the action of triggering master cock, the subject matter of this patent is: the level that the conversion of lift heavy signal is transmitted is many, the part of forming increases, the precision of load lifting limiter is affected, and equalizer pulley and hoisting crane integral body are isolated, component locations change in addition around causing, be difficult for installing and adjusting, when hoisting crane was worked, the equalizer pulley of reflection lift heavy signal was in quick condition, will produce vibration, increase deletrious mechanical vibration factor to hoisting crane, because the possible deflection of raising line, the equalizer pulley that is in quick condition will can reservation not transmit into this interfering signal, and cause the master cock misoperation.

Existing technology shows, still there is not a kind of applicability load lifting limiter of mechanical type widely so far both at home and abroad, especially to make lift heavy do the general-purpose overhead crane transfer crane of horizontal rectilinear motion and handling bridge etc. in the dolly mode, still the technical scheme that lacks feasibility, the lifting mechanism of this class hoisting crane adopts the transmission of duplex assembly pulley more, the fixed pulley group is placed under the trolley frame, make prior art be difficult to obtain suitable installation site, what have attempts to utilize the scheme that is associated with equalizer pulley, this not only still exists above-mentioned installation to adjust problem, and the hoisting crane of some tonnage, limit by the pulley multiplying power, equalizer pulley can only be installed on the running block at gib head position, at present, domestic at the hoisting crane of usefulness or the hoisting crane machine product of existing manufacturer production, major part does not also have supporting load lifting limiter, this situation far can not adapt to GB6067-85(crane safety rules) in defined should adorn the requirement that maybe should adorn load limiter by hoisting crane kind and tonnage, this problem has become current assurance hoisting crane normal operation, prevent accident, improve one of the key problem in technology in service life.

The objective of the invention is to provide a kind of applicability very strong; the load lifting limiter of the mechanical type that can be used widely; it should separate with hoisting crane is whole; under the condition that need not to change any scantling of structure on the hoisting crane; as one independently annex be installed to the position that multiple hoisting crane can adapt to and get on, and given play to its normal overload protection function.

The object of the present invention is achieved like this: under the crane carriage frame or near the fixed pulley group of elevator boom rack upper end, in walking around the fixed pulley group in the raising line branch of arbitrary pulley, a horizontal positioned is installed and makes its two ends and the symmetrical self contained system of fixed pulley sagittal plane vertical axis, it mainly is made up of three parts:

1, include resistance cylinders, the spring damping cylinder of spring, piston, push rod etc., and be attached to the thimble on the push rod and be attached to master cock on the resistance cylinders, as the main body triggering part.

2, the right-hand member of spring damping cylinder has pressure transmission pulley that links with push rod and two leading sheaves equidistantly arranging up and down with its, forms the signal conversion part branch.

3, the left end of spring damping cylinder, with a pressure-bearing pulley that links with resistance cylinders and and two leading sheaves up and down of its equidistant placement, form the support balance portion.

From the raising line branch that fixed pulley is drawn, behind the pressure transmission pulley of the leading sheave on pile warp right-hand member top, centre and the leading sheave of bottom, make raising line to angle of original vertical deflection, will reflect that then the rope tension of lift heavy signal is converted to the horizontal pressure that acts on the pressure transmission pulley.This pressure equals the product of two-fold rope tension and angle of deviation sine, and when angle of deviation was little, horizontal pressure will be finished the conversion of lift heavy signal, and transmit to the main body triggering part according to this than the remarkable reduction of rope tension.

With pressure transmission pulley bonded assembly push rod, under the effect of horizontal pressure, make the spring in the resistance cylinders produce distortion by piston, its amount of compression obviously is directly proportional with the lift heavy signal, and by reflecting with push rod bonded assembly thimble stroke, when the lift heavy overrate, thimble will trigger master cock, to cut off the lifting mechanism power supply.

From another root raising line branch that fixed pulley is drawn, when the pressure-bearing pulley of the top leading sheave of pile warp left end, centre and bottom leading sheave, equally rope tension is converted into horizontal pressure, because these three pulleys all link to each other with resistance cylinders, can balance play the support equilibrium activity from the horizontal pressure of right-hand member.

In addition, whole device is hinged on it under crane carriage frame or the crane arm upper end by means of connecting rod member, is the vertical state, plays automatic positioning effect.

The advantage of technical scheme provided by the present invention is:

1, simple bright the analysing of level transmitted in the conversion of the course of action from the lift heavy signal to master cock, other the number of packages amount of forming is little, reduced the error that assembling causes, because the shock damping action of spring damping cylinder and the support equilibrium activity of pulley system, get rid of interference as much as possible, have the little effect of composition error from the lift heavy inertia impact of all directions.

2, all design of parts are become an independent integral body compactness, that oad is little; be easy to adjust and demarcate; especially as the master cock of an electromechanical that has enlarged; can be as the annex of a complete machine; being installed to the position that polytype hoisting crane can adapt to gets on; have widely applicable effect, particularly solved the overload protection problem that general-purpose overhead crane, transfer crane and handling bridge etc. have a class hoisting crane of crane carriage effectively.

Concrete structure of the present invention is provided by following embodiment and accompanying drawing:

Fig. 1 is the front elevation of a specific embodiment of the present invention;

Fig. 2 is according to the A-A cutaway view on Fig. 1;

Fig. 3 is according to the B-B part sectional view on Fig. 2;

Fig. 4 is to partial view according to the C on Fig. 2.

Below in conjunction with installation position and connection mode, concrete structure and the service condition of description of drawings the present invention on hoisting crane.

Fig. 1 and Fig. 2 have expressed that installation position and the connection mode of the present invention on hoisting crane: Fig. 1 and Fig. 2 dashed rectangle are inner divides that to have expressed it be an independently single unit system, be placed in the fixed pulley group vicinity that includes fixed pulley [2] and fixed pulley axis [3] under the crane carriage frame [1], walk around the centre of the raising line left branch [4] and the raising line right branch [5] of fixed pulley [2], the integral body of invention by means of with resistance cylinders [6] affixed be connected wing plate [7], after passing all raising line branches of the right and left, be connected with link plate [9] on being cemented in fixed pulley axis [3] with boatswain chair [8], such connection mode, can guarantee that section raising line that interrelates with the present invention is in vertical as much as possible, play automatic positioning effect.

Fig. 1 has expressed concrete structure of the present invention and service condition: behind the pressure transmission pulley [11] and bottom right leading sheave [12] in the middle of the right branch [5] of raising line is walked around upper right pulley [10], make this section raising line to angle of the outside deflection of original vertical, the raising line pulling force of the pressure transmission pulley [11] in the middle of walking around, go up synthetic horizontal pressure at pressure transmission pulley [11], the raising line pulling force of reflection lift heavy signal then is converted into horizontal pressure, pass to the spring damping cylinder that is connected with pressure transmission pulley [11] simultaneously, spring damping cylinder is mainly by resistance cylinders [6], spring [13], piston [14], push rod compositions such as [15], be subjected to the horizontal pressure of pressure transmission pulley [11] when push rod [15], pass to the piston affixed [14] with push rod, spring [13] is subjected to the compression of piston [14] and is out of shape, its deflection obviously is directly proportional with the lift heavy signal, and reflect by the stroke of push rod [11], when the lift heavy overrate, will make the triggering part action.

Fig. 4 has expressed the concrete structure and service condition of triggering part: since with datum plate [16] that push rod [15] is connected on thimble [17] the reflection push rod stroke had, and can pass through the thread connection between thimble [16] and datum plate [17], adjust and demarcate, when the lift heavy overrate, can trigger and the affixed master cock [18] of resistance cylinders [6], so, the normally closed contact of master cock disconnects, the control circuit outage, and the lifting mechanism power circuit is cut off, and lifting mechanism quits work automatically, and normal opened contact is connected in the master cock simultaneously, and the circuit that red light and loudspeaker are housed is connected, signal gives the alarm.

Fig. 3 has expressed the concrete structure and the service condition of spring damping cylinder, in order to get rid of the influence of lift heavy inertia impact, prevent the malfunction in advance of master cock, in damping spring cylinder body [6], fill hydraulic oil [19], when lift heavy, piston [14] is compression spring [13] left, and the hydraulic oil [19] that pushes its left side moves, it is discharged from damping hole [20], get back in the cavity of piston [14] the right resistance cylinders, when unloading, spring [13] resets, piston [14] moves to right, and the hydraulic oil [19] in the cavity of pushing the right is discharged from damping hole [20]; Get back to again in the cavity on piston [14] left side, with the spinning in and out of resistance cylinders [6] with the damping adjustment valve [21] of thread connection, can adjust the size of shock damping action, damping cylinder cap [22] seals.

Fig. 1 has also expressed concrete structure and the service condition that the present invention supports balance portion: when walking around the raising line left branch [4] that fixed pulley comes out, walk around upper left leading sheave [23], behind middle the pressure-bearing pulley [24] and lower-left leading sheave [25], obviously the raising line pulling force that also will walk around pressure-bearing pulley [24] is converted into horizontal pressure, this pressure is passed to the resistance cylinders that is connected with pressure-bearing pulley [24], with balance from the right pressure transmission pulley [11], through push rod [15], piston [14], spring [13] gives the duty pressure that waits of resistance cylinders [6], again by means of triatic stay [27], vertically strut [26] and the connection tube head [28] that connects them make each leading sheave [10], [12], [23], [25], all with resistance cylinders [6] Joint, this is just with the left side of raising line, right two branches [4], the external force that is produced when [5] walking around them, mutual balance and be converted into each part [26] in addition that connects them, [27], [28], [6] internal force, support the effect of balance portion also to be with a raising line left side, right two branches [4], [5] link together, be not subjected to the influence of raising line deflection, by means of the thread connection that connects between tube head [28] and vertical strut [26] and the triatic stay [27], adjust each leading sheave [10], [12], [23], [25] in the spacing of level and vertical direction, so that adjustment of the present invention and demarcation.

Claims (3)

1, a kind of load lifting limiter that is used for hoisting crane, comprise pulley system, spring [13], the thimble [17] relevant with spring [13] deflection, master cock [18] is characterized in that it is an independently single unit system, with by two branches [4] about the raising line of fixed pulley [2], [5] interrelate, its base portion is a spring damping cylinder, directly link to each other with the pulley system that belongs to device proper, wherein pressure-bearing pulley [24] and pressure transmission pulley [11] are positioned at the left side of spring damping cylinder, right two ends, be connected with push rod [15] with resistance cylinders [6] respectively, upper left leading sheave [23], lower-left leading sheave [25] and upper right leading sheave [10], bottom right leading sheave [12] is respectively along a raising line left side, right two branches [4], [5] direction, horizontal center line with spring damping cylinder is an axis symmetric arrangement up and down, and links together with resistance cylinders [6].

2, load lifting limiter according to claim 1, it is characterized in that with left and right two branches of raising line [4] by fixed pulley [2], [5] respectively around to upper left leading sheave [23], pressure-bearing pulley [24], lower-left leading sheave [25] and upper right leading sheave [10], pressure transmission pulley [11], bottom right leading sheave [12], simultaneously by means of resistance cylinders [6] and the connection that is connected wing plate [7], boatswain chair [8], link plate [9], be placed in it under crane carriage frame or elevator boom rack on.

3, load lifting limiter according to claim 1 is characterized in that spring damping cylinder has resistance cylinders [6] with damping hole [20], spring [13], piston [14] push rod [15], damping port lid [22], damping and adjusts in the cavity of valve [21] spring damping cylinder and fill hydraulic oil [19].

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