US3435915A - Lifting installation - Google Patents

Description

April 1, 1969 J."VILLARS LIFIING INSTALLATION Sheet Filed Jan. 51, 1967 April 1,1969 Vl LLARS Q I 3,435,915 51 v LIFTING INSTALLATION V Filed Jan. 31, 1967 A? of 5 Sheet April 1, 1969 J. VILLARS 3,43

LIFTING INSTALLATION Filed Jan. 51, 1967 Sheet 5 of 3 I 6 as LLLLH .UHU. .U.LLLU..\.LLLLLH "l X "11mm l llLlllll lllllll United States Patent Int. Cl. B66f 7/00; B60s 13/00; F16b 7/ 12 US. Cl. 187-8.47 Claims ABSTRACT OF THE DISCLOSURE This disclosure concerns a lifting appliance comprising lifting and lowering means including a plurality of flexible cables which are anchored at the top of corresponding supporting columns dispersed about said moving means and which have vertical runs down the respective columns and around pullies on the moving means to power drive means independent of the moving means and comprising safe failure means operative if a cable becomes slack or breaks, formed by vertical rods on the columns; the horizontal pivoted locking plate loosely threaded on each rod and a support for each locking plate which is mounted on the moving means and normally holds the plate horizontal so that the rod can travel freely therethrough and which tilts when the support is removed by tilting the moving means so as to grip the respective vertical rod.

In a known construction, the movable equipment is suspended by columns by means of cables which pass through pulleys fixed to this movable equipment. In case of rupture of a cable, the traction acting on the corresponding pulley disappears and permits springs to actuate jaws which wedge between the corresponding column and the movable equipment thus immobilizing the latter so that it does not fall.

This safety system operates very well, but if a cable stretches without breaking, the system is inoperative. Thus deformations of the movable equipment and stresses compromising its resistance can result. A deformation which is too pronounced can even lead to the fall of the lifted object.

The accompanying drawings show, by way of example, one embodiment of the invention.

FIGURE 1 shows schematically a lifting installtion having lifting cables.

FIGURE 2 shows the safety device of one of the support columns in rest position.

FIGURE 3 shows the device of FIGURE 2 after its operation, thus in locked position.

FIGURE 4 shows a part of the motor column.

FIGURE 5 shows a view in axial section through the motor column.

FIGURE 6 shows the pieces of FIGURE 5 after being tripped.

The installation shown, intended to raise an automobile, comprises, like other known installations, a movable equipment or platform constituted by two cross beams 1 and 2 on which rest two rolling tracks 3 and 4.

This movable equipment is disposed between four columns, three of which 5, 6 and 7, called support columns, have for their role to support and to guide it. The fourth column 8, called motor column, contains a long screw 12 (FIGURE 5) driven by an electric motor. Three of the corners of the movable equipment bear against the cables 9, 10 and 11 disposed as in FIGURE 1. One end of these cables is fixed at the top of the corresponding support column, while their other end is fixed to the foot of the motor column. The fourth corner bears against the nut 13 engaged on the screw 12.

Each support column comprises a safety device operating in case of rupture or of exaggerated elongation of the corresponding cable. We will describe the one which corresponds to the column 7. The bar 25 (FIGURE 2) hooked freely by its head 26 to the upper plate of the column, passes freely through the circular hole 30', preferably having sharp edges, of the plate 27. This plate can pivot freely about an axle 28 hearing on the two vertical plates 26 which terminate the cross beam 2. The hole 30 is formed in the bottom of a clearance 31 of the plate 27 so as to permit the plate to turn by an angle suflicient with respect to the horizontal so that the edges of the hole 30 can bear strongly against the bar 25.

A stop 29 permits the plate 27 to remain normally horizontal, that is to say perpendicular to the bar 25. A second stop 32 also fixed to the vertical plates 26 is located at a small distance from the bar 25. It is seen that the cross beam and the pieces which carry the latter can freely be displaced vertically along the bar 25, the latter presenting no obstacle to their movement.

In case of an abnormal stretching or of rupture of the lifting cable, the operation of this device is the following. Since the cross beam 2 is inclined, the stop 32 presses against the bar 25, pushes the latter against the edge of the hole 30, causes the plate to rock and the edges of this hole 30 dig themselves into the bar 25 thus connecting the latter rigidly with the end of the cross beam which is thus maintained in place and can no longer descend in spite of the failure of this cable.

Another constructive formula consists in replacing the pivoting plate 27 by a plate forming a body with the plates 26, and the stop 32 by another plate also fixed, the two being equipped with conical holes having very sharp edges. In this case, any inclination of the cross beam causes a tightening of the bar 25 between the two holes whose edges dig into the bar with the same effect as here above.

The holes of the plate 27, instead of being conical, can have another profile, for example can be cylindrical or formed obliquely so as to obtain an edge having an acute angle with the bar 25.

The safety device represented in FIGURES 2 and 3 or its variants are completed by a tripping device for stopping the driving motor of the screw 12 and which we will describe here below.

On the motor column 8 (FIGURE 4) the driving box 14 equipped with the hand lever 15 permits the operation to be controlled, in one direction or the other, of the motor driving the screw 12. When one pushes the lever 15 towards the top, the movable equipment rises; it descends by pushing the lever towards the bottom. The motor stops when the lever is horizontal.

A second lever 24 placed at the other end of the axle of the lever 15 is articulated to the end of the bent rod 21 on which are located two stops 22 and 23. The rod 21 passes freely through a hole of the projection 20 rigid with the cross beam as well as through a hole formed at the end of the lever 18 equipped with a counter-weight 19 and which can freely turn around the axle 33 rigid with the nut 13. Normally the counter-weight 19 maintains the lever 18 borne against the projection 20.

When at the end of the upward stroke of the movable equipment the projection 20 reaches the stop 22, it displaces the rod 21 slightly from the bottom towards the top and brings back the lever 15 into the stop position.

Similarly, when during descent of the platform, the stop 23 comes into contact with the lever 18 borne against the projection 20, the rod 21 is drawn from the top towards the bottom, which brings back the lever 15 into the stop position of the motor.

The lower end of the rod 21 is articulated at 36 with the lever 34 which can freely pivot about the axle 36 (FIGURE 5). Its vertical branch 37 can oscillate freely between the stops 38 and 39 of the tripper 40 and can follow the movements of the lever 15 of the box 14. The tripper 40 can pivot freely about the axle 41 but it is maintained in place by the thrust of the rod 42 on which bears the spring 43.

The lower end of each of the suspension cables 9, 10 and 11 is provided with a tip 44 hooked to a stud hole 45 of the column 8. A spring 46 bears horizontally on this tip which the traction of the cable maintains in position.

If, following a rupture of the cable, or the tripping of one of the plates 27, or again the meeting of an obstacle placed under the movable equipment the traction on one of the tips 44 disappears, the corresponding spring 46 pushes this tip (FIGURE 6) which disengages from its stud hole and presses on the tripper 40 which begins a pivoting movement about its axle 41. This movement is amplified under the effect of the spring 42, the two stops 38 and 39 frame and grip strongly the branch 37 which they bring into vertical position and the rod 21 takes the place corresponding to the stop as it is shown in FIGURE 6, which stops the motor.

On the other hand the nut 13 is provided with two pins of which one 47 is visible in FIGURE 5. The cross beam 1 is completed by two terminal plates 16 and 17 each provided with a notch resting on the pins of the nut 13. If during the upward travel of the movable equipment any obstacle whatsoever impedes the end of the cross beam 1 from following the nut 13, the pins of this latter separate from the notches of the plates 16 and 17. The centre of pivoting 33 of the lever 18 descends with respect to the projection 20, the lever 18 becomes inclined, the edges of the hole with which it is provided and through which passes the rod 21 grip the latter which is driven towards the bottom and causes the stop of the motor. The figure shows that the switch can nevertheless be put in operating position for the opposite direction in order to permit the disengagement of the obstacle met.

I claim:

1. In a lifting appliance: horizontal moving means including a pair of cross beams each provided at each end with a pair of vertical, spaced, terminal plates: four columns dispersed about said moving means, three of said columns serving to guide and support said moving means, said fourth column having therein a driven member secured to said terminal plates of one of said cross beams, pulleys on said moving means and flexible cables on said pulleys for raising and lowering said moving means; one end of said cables being secured at the top of a corresponding support column and the other end thereof being secured to the foot of said fourth column; each of said support columns having a safety device including an elongated member suspended to said column,

a normally horizontal tipping plate freely pivoted on said terminal plates and being free of spring urging; said tipping plate having a cylindrical recess directed towards said moving means with a central opening smaller than said recess and receiving therein said elongated member, said opening being of a size such as to allow said plate to tilt sufiiciently with respect to the horizontal so that the edges of the said opening can directly jam and hold said elongated member and hence said platform when said cross beam becomes inclined relative to said column because of abnormal stretching or rupture of said cables.

2. Lifting appliance according to claim 1, wherein a first stop is provided on said terminal plates for holding said tipping plate normally horizontal and perpendicular to said elongated member.

3. Lifting appliance according to claim 2, wherein said terminal plates have in their upper part a second stop mounted near said elongated member and adapted to press against said member thereby pushing said member against the edge of said opening and pivoting said tipping plate.

4. Lifting appliance according to claim 1, having a motor for driving said driven member and means for stopping said motor, said means comprising a first lever pivoted on an axle for controlling the direction of movement of said motor, a second lever pivoted on said axle, said second lever being pivoted on the end of a bent member, said bent member carrying upper and lower stops, a projection on said platform, said projection having an opening through which passes said rod and adapted to contact said stops when said platform has reached the end of its upward and downward movement, and thereby bring said first lever into stop position for said motor.

References Cited UNITED STATES PATENTS 1,352,172 9/1920 Brandon 29482.26 1,505,220 8/1924 Shay 24243.12 2,483,828 10/1949 Hanif 187-81 3,291,260 12/1966 Woor 1878.59

FOREIGN PATENTS 1,123,451 2/1959 Germany. 1,303,096 6/1962 France.

724,512 2/1955 Great Britain.

EVON C. BLUNK, Primary Examiner.

H. C. HORNSBY, Assistant Examiner.

US. Cl. X.R.

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