CN201250078Y - Double-braking electric block - Google Patents

Abstract

The utility model aims at providing a double-braking electric block which only brakes when a first brake gear is out of order or other failures are got, which relates to a brake gear. The key point of the technical proposal is that the double-braking electric bloc comprises a second brake gear whose structure is that a brake hoop which is provided with an opening is arranged on the winding drum, and a cam and a ratchet wheel with openings are arranged on the brake hoop outside the winding drum, two screws respectively penetrate in the cam and a threaded through hole on the end surface of the opening of the ratchet wheel, and threads of the screws respectively penetrate through the threaded through holes on the opening end surfaces of the cam and the ratchet wheel, and the and threads of the screws and the cam are matched with a threaded hole in the other end surface of the opening of the ratchet wheel, and the upper portion of the threaded through hole is provided with a step hole to be opposite to the inner end surface of the end caps of the screws, arc-shaped grooves are evenly distributed on the periphery surface of the cam, and the connector between the two arc-shaped grooves is provided with an outwards convex arc-shaped surface, and detent grooves are evenly distributed on the periphery surface of the ratchet wheel. The double-braking electric block is suitable for electric hoists.

Description

A kind of double-brake electric hoist

Technical field:

The utility model relates to a kind of drg, particularly a kind of double-brake electric hoist.

Background technology:

Electric block in the dangerous operation environment hoisting crane or electric block for safety, requirement is provided with second drg, yet existing second drg is normally closed brake, its shortcoming be switch on or the no power drg all in running order, thereby the service life of this second drg is shorter, can not play the effect of insurance over a long time.

Summary of the invention:

The purpose of this utility model provides a kind of double-brake electric hoist of only just braking at first brake failure or when other faults take place.The technical solution of the utility model is, a kind of double-brake electric hoist, comprise second drg, it is characterized in that: the structure of described second drg is, reel is provided with the brake hoop of opening, the cam of opening and ratchet place on the outer brake hoop of reel, two screws are through at respectively in the screw thread via hole in cam and the ratchet open end, tapped bore in its screw thread and cam and the ratchet opening other end matches, the top of above-mentioned screw thread via hole has a stepped hole relative with the termination inner end surface of screw, uniform deep-slotted chip breaker on the side face of cam, the junction between two deep-slotted chip breakers are the arcwall face of evagination, uniform pawl slot on the side face of ratchet; Be provided with the bearing that is connected with the reel outer cover in the outside of cam and ratchet, the middle part of swing arm and the axle normal-running fit that is fixed on the bearing, the upper end of above-mentioned swing arm is provided with roller and contacts with the deep-slotted chip breaker side face of cam, the pawl slot that its lower end is provided with on ratchet and the ratchet matches, one end of spring is connected with the reel outer cover, and the other end is connected with swing arm.It is relative with the lip-deep convex body of swing arm to be provided with travel switch on another surface of bearing.The utility model has long service life and safe and reliable remarkable advantage compared with the prior art.

Description of drawings:

Fig. 1 is the front view of the utility model double-brake electric hoist, and Fig. 2 is the front view of second drg, and Fig. 3 is the back view of Fig. 2.

The specific embodiment:

In conjunction with above accompanying drawing the utility model is elaborated, first drg that the utility model uses is that conventional band brake lifting motor 1, the second drg 3 that uses is directly to reel 2 brakings.The structure of the utility model second drg is to be provided with brake hoop 5 on the outer peripheral face of reel one end, ratchet 4 and cam 17, place on the outer brake hoop of reel, being evenly equipped with ratchet slot 14 on the periphery of ratchet, being evenly equipped with deep-slotted chip breaker on the periphery of cam, is the cambered surface of an evagination between the deep-slotted chip breaker.On reel outer cover 16, be fixed with a bearing 13, the middle part of swing arm 7 and axle 12 normal-running fiies that are fixed on the bearing, the upper end of swing arm one side is provided with roller 6 and contacts with the deep-slotted chip breaker side face of cam, the pawl slot that is provided with on ratchet 10 and the ratchet in the lower end of its opposite side matches, one end of spring 8 is fixed, the other end is connected with swing arm, and ratchet breaks away from ratchet surface under the normal condition of spring, can not insert in the pawl slot.It is relative with face of cylinder convex body 9 in the swing arm that bearing is provided with travel switch 11.The purpose that brake hoop is set is the instant impact in order to slow down ratchet and to enter ratchet slot, avoids stop mechanism is produced damage.This friction braking, must make ratchet, connection between brake hoop and the reel is tight, for this reason, brake hoop is made opening and the girth girth less than reel, itself and reel are fitted tightly, in order to make ratchet, cam can be fitted closely with reel, guarantee to have enough big friction brake torque, between the open end of annulus, be provided with elastic cushion block, establish tapped blind hole in the end face of opening annulus, it is relative with above-mentioned tapped blind hole to be provided with the screw thread via hole in the other end of opening annulus, and screw 15 passes the screw thread via hole and screws in the tapped blind hole, the screw head end face places on the stepped hole end face of screw thread via hole upper end, makes cam and the ratchet and the brake hoop of opening, reel is held tightly.

Principle of work of the present utility model is, electric block is when hoisting weight, when first brake failure or occur that axle is disconnected, during the disconnected weight free fall of tooth, when drum speed reaches certain rotating speed (normal speed 1.25 times), the amplitude that the centnifugal force of the roller of camming action in swing arm makes swing arm outwards get rid of pendulum increases, and overcomes spring force, and ratchet inserts in the ratchet slot, reel is stopped operating, and this moment, weight was parked in the air.When the swing of swing arm, the convex body in the swing arm is depressed travel switch, makes the outage of decline contactless switch can not descend and can only rise.Drop on the ground in order to be suspended in aerial weight, can press the rising button, reel rising (with the switched in opposite that descends), ratchet spins off from pawl slot under the effect of spring, close the rising button, reel stops to rise, behind the free fall certain distance, braked once more, repeatedly repeat above-mentioned action weight safety is dropped on the ground.

Claims (2)

1, a kind of double-brake electric hoist, comprise second drg, it is characterized in that: the structure of described second drg is, reel is provided with the brake hoop of opening, the cam of opening and ratchet place on the outer brake hoop of reel, two screws are through at respectively in the screw thread via hole in cam and the ratchet open end, tapped bore in its screw thread and cam and the ratchet opening other end matches, the top of above-mentioned screw thread via hole has a stepped hole relative with the termination inner end surface of screw, uniform deep-slotted chip breaker on the side face of cam, junction between two deep-slotted chip breakers is the arcwall face of evagination, uniform pawl slot on the side face of ratchet; Be provided with the bearing that is connected with the reel outer cover in the outside of cam and ratchet, the middle part of swing arm and the axle normal-running fit that is fixed on the bearing, the upper end of above-mentioned swing arm is provided with roller and contacts with the deep-slotted chip breaker side face of cam, the pawl slot that its lower end is provided with on ratchet and the ratchet matches, one end of spring is connected with the reel outer cover, and the other end is connected with swing arm.

2, a kind of double-brake electric hoist as claimed in claim 1 is characterized in that: it is relative with the lip-deep convex body of swing arm to be provided with travel switch on another surface of bearing.

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