DE102004035222B3 - Safety crank to raise and lower loads has pressure piece connected to coupling fixing it in one end position against rotation, but leaving it free in other end position - Google Patents

Abstract

The safety crank has a pressure piece (1) and a locking wheel (3) with brake discs (10) on both sides. A hand crank (4) is concentric to the pressure piece at the bearing eye (5), and is in working connection with a setting ring (8) connected to the pressure piece. The pressure piece is connected to a coupling fixing it in one end position against rotation, but leaving it free in the other end position.

Description

The The invention relates to a safety crank for lifting and lowering of Loads according to the generic term of claim 1.

Such safety cranks, as they are known from the DE 94 17 414 U1 are known to be used on different hoists and are used in many ways, for example in construction, agriculture, vehicle or general engineering.

at activity the hand crank in the sense of lifting the load is in correspondence generated with the collar a certain axial stroke through which the Brake discs against the pressure piece be pressed, so that the rotary motion of the hand crank directly transferred to the pressure piece becomes.

there stores the pressure piece secured against rotation on a load shaft, so by turning the hand crank and thus the pressure piece Also, the load shaft is rotated to raise and lower the load.

In In any case, turning the hand crank into one or the other Direction required. In load-lowering direction, even if no load attaches, but for example a rope wound on a cable drum so far as to be unrolled, that for example a hook to a Load attached can be, with the cable drum is connected to the load shaft.

Just if a longer one Piece of rope should be drained to absorb the load is the constant cranking a considerable handling difficulties.

These is then particularly pronounced if the load is not vertical or nearly vertical, but at a relatively shallow angle to the horizontal, since the turning back The hand crank does not pass the hooked end of the rope the gravity is handled, but for example on the ground remains and often verkneult, so that the rope only after a elaborate untangling can be led to the load.

there is also the length to be handled of the rope can not be estimated easily, which is dependent from the distance of the load to the safety crank or cable drum, so that this also results in handling disadvantages.

Of the The invention is therefore based on the object, a safety crank of the generic type develop so that their handling is improved. These Task is solved by a safety crank, which has the characteristics of the claim 1 has.

By this structural design of the safety crank is made possible that the drive part, preferably the hand crank, only be operated must if a load is to be raised or lowered.

In the case, that the rope located on the connected cable drum is load-free should be drained, the hand crank out of engagement with the load shaft be brought so that the load shaft and with it a coupling sleeve of Can turn the clutch, while the hand crank, the pressure piece, the ratchet, the brake discs and the collar, which together form a structural unit, stay free from rotation.

Thereby is for draining or unwinding of the rope no rotation of the hand crank more required. Rather, a pull on the free end of the range Rope to unwind from the winch, if necessary if the rope or an attached Load hooks are discharged vertically, this is already done by the weight of the load hook.

Around move said assembly from the locking position to the coupling sleeve, The unit is only to a certain extent on the coupling sleeve axially displaced until the rotation is disengaged. It can the axial displacement by a provided on the coupling sleeve Stop be limited.

to Anti-rotation are according to another idea of the invention Positive locking means provided, on the one hand with the movable assembly and on the other hand correspond to the coupling sleeve.

Such Positive locking means can be designed as rollers, balls or other carriers, in one of the coupling sleeve facing end portion of the pressure piece are fixed and on the other hand in adapted guideways the coupling sleeve intervention.

The Shaping these inner webs allows on the one hand, the axial displacement of the pressure piece and the associated components and on the other hand, the entrainment of the coupling sleeve and the inserted load shaft upon rotation of the hand crank.

At Location of said cable drum can be a gear on the load shaft or the like connected via the coupling sleeve and the connected components can be driven.

Otherwise draws The invention is characterized in that they are very simple and inexpensive too realize is because only a few additional, easy to edit Parts are required. This circumstance is therefore a special one Meaning too, because such safety cranks in large numbers Find use. The simple design also allows the upgrade existing safety cranks with couplings according to the invention.

In spite of the improved handling of the safety crank is their operability not restricted in any way.

Further advantageous embodiments of the invention are characterized in the subclaims.

One embodiment The invention will be described below with reference to the accompanying drawings.

It demonstrate:

1 a safety crank according to the invention in a partially sectioned side view

2 a partial section of the safety crank after 2 , also in a cut side view

3 a side view on a detail of the safety crank

4 a top view of the detail 3

In the 1 A safety crank for lifting and lowering loads is shown, which is a coupling sleeve 2 shows, with a square socket 14 in which a load shaft, not shown, can be inserted, with which a cable drum, a transmission or the like can be driven.

On the coupling sleeve 2 is a pressure piece 1 stored, which in turn is a ratchet wheel 13 as well as a bearing eye 5 a winch 4 also carries a lever 6 like a handle attached to it 7 having.

The funnel-shaped ratchet wheel has teeth on its circumference 13 in which an unillustrated, stationary pawl engages in case the hand crank 4 is released unintentionally when countersunk load.

Next are at the two end faces of the ratchet wheel 3 brake discs 10 provided, one of which on the pressure piece 1 and the other on the facing end of the bearing eye 5 is applied.

A collar 8th acting on an external thread of the pressure piece 1 is screwed on and by means of a screw 9 secured to it stands with the bearing eye 5 in operative connection, wherein the mutually facing surfaces of the adjusting ring 8th and the bearing eye 5 are shaped so that an axial displacement of the bearing eye 5 gives, thereby freeing the handle 4 or a braking occurs. Since the operation of such a safety crank is known, there is no need for further explanation.

In the in the 1 the example shown is the safety crank in a load-lifting or a load-lowering position. This is the pressure piece 1 positive fit with the coupling sleeve 2 engaged, including bullets 12 are provided, which in T-shaped inner tracks 11 the coupling sleeve 2 einliegen ( 3 ).

Here are the inner webs 11 in a cuff 15 the coupling sleeve 2 intended. For storage of the balls 12 in entrainment direction, the inner webs extend 11 circumferentially of the coupling sleeve 2 , ie transverse to the longitudinal axis.

To Endkuppeln the pressure piece of the coupling sleeve closes to the respective circumferential inner race 11 a passage 16 in width about the diameter of the ball 12 corresponds, so that with a relative axial displacement of the pressure piece 1 opposite the coupling sleeve 2 the ball 12 from the cuff 15 exits and on the shaft of the coupling sleeve 2 can rotate freely.

The two ends of the circumferential inner track 11 each form a stop for driving the coupling sleeve 2 or the connected load shaft when lifting or lowering the load.

In place of the balls 12 can also other drivers in the pressure piece 1 be attached, such as cylindrical rollers or pins.

Otherwise, the length of the displacement of the pressure piece 1 on the coupling sleeve 2 , which is limited by one on the coupling sleeve 2 attached stop 17 , Preferably a locking ring, at least by the measure of the ball diameter longer than the length of the passage 16 , so that a free rotation is ensured in the hinged end position.

1

Pressure piece

2

coupling sleeve

3

ratchet wheel

4

winch

5

bearing eye

6

lever

7

Handle

8th

collar

9

screw

10

brake disc

11

inside track

12

Bullet

13

tooth

14

Inside Square

15

cuffs

16

passage

17

attack

Claims (8)

Safety crank for lifting and lowering loads, with a pressure piece ( 1 ), a ratchet wheel guided thereon ( 3 ), at the two end faces of brake discs ( 10 ) are provided, one of which to the pressure piece ( 1 ) and the other to an end face of a concentric to the pressure piece ( 1 ) arranged Lagerauges ( 5 ) is applied to a drive part, the one with the pressure piece ( 1 ) connected adjusting ring ( 8th ) is in operative connection, characterized in that the pressure piece ( 1 ) with a torsionally and axially secured to a load shaft holder clutch in one end position against rotation and is freely rotatably connected in the other end position. Safety crank according to claim 1, characterized in that the coupling is a coupling sleeve ( 2 ), on which the pressure piece ( 1 ) Is mounted axially displaceable. Safety crank according to claim 1 or 2, characterized in that the pressure piece ( 1 ) in rotationally secured end position via driver with the coupling sleeve ( 2 ) connected is. Safety crank according to one of the preceding claims, characterized in that the drivers on the pressure piece ( 1 ) and disengageable in inner webs ( 11 ) of the coupling sleeve ( 2 ) are guided. Safety crank according to one of the preceding claims, characterized in that the driver balls ( 12 ) or rolls are. Safety crank according to claim 4 or 5, characterized in that the inner webs ( 11 ) in a cuff ( 15 ) of the coupling sleeve ( 2 ) are provided and extend partially in the circumferential direction and a passage ( 16 ) for the driver to the shaft of the coupling sleeve ( 2 ) exhibit. Safety crank according to one of the preceding claims, characterized in that the axial displacement of the pressure piece ( 1 ) on the coupling sleeve ( 2 ) by a stop ( 17 ) is limited. Safety crank according to one of the preceding claims, characterized in that the length of the axial displacement to the associated dimension of the driver, preferably the ball ( 12 ), is longer than the length of the passage ( 16 ).