Double-reeved lifting device with a latch-locking mechanism
11591191 ยท 2023-02-28
Assignee
Inventors
Cpc classification
B66C2700/017
PERFORMING OPERATIONS; TRANSPORTING
B66D3/10
PERFORMING OPERATIONS; TRANSPORTING
B66C13/00
PERFORMING OPERATIONS; TRANSPORTING
B66D3/043
PERFORMING OPERATIONS; TRANSPORTING
International classification
B66D3/10
PERFORMING OPERATIONS; TRANSPORTING
B66D3/04
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A double-reeved lifting device includes a lower reeve block secured to a lifting hook and an upper reeve block, wherein the two reeve blocks include reversible connection means adapted to be reversibly configured between a connected configuration and a disconnected configuration. The reversible connection means include a locking mechanism and a complementary locking structure having a frame securely supporting a bolt. The locking mechanism includes a chassis having a locking channel provided with a mouthpiece through which the bolt is configured to enter and exit and slide in the locking channel respectively upon a relative approach or distancing between the two reeve blocks, and at least one latch pivotally mounted on the chassis so as to pivot inside the locking channel, the latch provided with a free end adapted to engage with the bolt.
Claims
1. A double-reeved lifting device for a lifting machinery, the lifting device comprising: a lower reeve block secured to a lifting hook and an upper reeve block, wherein the reeve blocks comprise reversible connection means adapted to be reversibly configured between: a connected configuration in which the upper reeve block is connected to the lower reeve block so as to be able to accompany the lower reeve block in ascending/descending movements along a main axis, and a disconnected configuration in which the upper reeve block is disconnected from the lower reeve block so as to be able to remain hanging above the lower reeve block such that the lower reeve block is configurated to perform descending/ascending movements without the upper reeve block, wherein the connected configuration and the disconnected configuration respectively correspond to a double-reeved configuration and to a simple-reeved configuration, or vice versa, of the double-reeved lifting device, wherein the reversible connection means comprise a locking mechanism mounted on one of the two reeve blocks, and a complementary locking structure mounted on the other one of the two reeve blocks and adapted to cooperate with the locking mechanism, wherein the complementary locking structure comprises a frame securely supporting a bolt formed at least partially by a shaft extending transversely to the main axis, and wherein the locking mechanism comprises: a chassis comprising a locking channel having an elongated shape along the main axis and provided with a mouthpiece through which the bolt is configured to enter into and exit out of the locking channel and slide in the locking channel in an entry direction and in an exit direction, opposite to the entry direction, respectively upon a relative approach or distancing between the two reeve blocks, and at least one latch pivotally mounted on the chassis about a pivot axis so as to pivot inside the locking channel, wherein the latch is provided with a concave-shaped free end adapted to engage with the bolt, and is coupled to an elastic biasing element urging the latch towards a neutral position.
2. The double-reeved lifting device according to claim 1, wherein the latch is pivotally movable between: the neutral position; a distal position, in which the latch clears the passage for the bolt by the effect of a push exerted by the bolt sliding in the entry direction, wherein the distal position is associated to a pivoting of the latch in a distal rotational direction from the neutral position; a proximal position, in which the latch clears the passage for the bolt by the effect of a push exerted by the bolt sliding in the exit direction, wherein the proximal position is associated to a pivoting of the latch in a proximal rotational direction, opposite to the distal rotational direction, from the neutral position; and a locking position, intermediate between the neutral position and the distal position, in which the free end of the latch blocks sliding of the bolt in the locking channel in the exit direction, with the bolt stuck inside said free end.
3. The double-reeved lifting device according to claim 1, wherein the free end of the latch has an indentation with a shape complementary to the bolt.
4. The double-reeved lifting device according to claim 3, wherein the bolt has a cylindrical section at a determined diameter, and the indentation of the free end of the latch has a circle-arc shaped load-bearing area.
5. The double-reeved lifting device according to claim 4, wherein the circle-arc shaped load-bearing area of the indentation of the latch has a diameter equivalent to the diameter of the bolt.
6. The double-reeved lifting device according to claim 4, wherein the locking channel has a width substantially equivalent to the diameter of the bolt.
7. The double-reeved lifting device according to claim 3, wherein the indentation of the free end of the latch is delimited by two opposite sears on which the bolt configured to exert a push, the two opposite sears including a proximal sear facing the mouthpiece of the locking channel in the neutral position, and a distal sear, wherein the proximal sear and the distal sear respectively have a proximal length and a distal length measured radially from the pivot axis, and the proximal length is smaller than the distal length.
8. The double-reeved lifting device according to claim 1, wherein the locking channel has a bottom, adapted to stop a sliding of the bolt in the entry direction, wherein the latch is disposed between the mouthpiece and the bottom of the locking channel.
9. The double-reeved lifting device according to claim 1, wherein the pivot axis of the latch is orthogonal to the main axis.
10. The double-reeved lifting device according to claim 1, wherein the at least one latch of the locking mechanism comprises two latches facing each other, pivotally mounted on the chassis on either side of the locking channel, the two latches being pivotable symmetrically with respect to a main plane including the main axis and parallel to the pivot axis of each of the two latches.
11. The double-reeved lifting device according to claim 10, wherein the two latches are identical and symmetrical with respect to the main plane.
12. The double-reeved lifting device according to claim 1, wherein the frame of the complementary locking structure comprises two flanges facing each other, between which the bolt is fastened.
13. The double-reeved lifting device according to claim 1, wherein the chassis of the locking mechanism comprises two plates between which the latch is pivotally mounted.
14. A lifting machinery comprising a jib and the double-reeved lifting device of claim 1 formed so as to lift/lower a load along the jib, wherein the lower reeve block hangs from the jib by a lifting rope connected to a lifting winch to make the lower reeve block ascend/descend, the lifting rope passing through the upper reeve block, and wherein: starting from the disconnected configuration with the upper reeve block hanging above the lower reeve block and with the latch in the neutral position, the lower reeve block is configured to be raised for a relative approach between the two reeve blocks until the upper reeve block reaches a high stop on the jib and the bolt comes into the locking channel through the mouthpiece, slides inside the locking channel in the entry direction and exerts a push on the latch to bring the latch in a distal position until fitting inside the free end of the latch, and then the lower reeve block is configured to be displaced in descent so that the bolt slides inside the locking channel in the exit direction and brings the latch in a locking position, so that the bolt is stuck inside the free end and sliding of the bolt in the locking channel in the exit direction is blocked, so that the lower reeve block is configured to descend with the upper reeve block in the connected configuration; and starting from the connected configuration with the latch in the locking position and the bolt stuck inside the free end of the latch, the lower reeve block is configured to be raised until the upper reeve block reaches the high stop on the jib, and then the bolt slides inside the locking channel in the entry direction and brings the latch in an intermediate distal position, so that the bolt leaves the inside of the free end of the latch and afterwards the latch returns back into the neutral position by the effect of the elastic biasing element, and then the lower reeve block is configured to be displaced in descent so that the bolt slides inside the locking channel in the exit direction, pushes the latch towards a proximal position until coming out of the locking channel and being released from the latch, so that the lower reeve block is configured to continue descending in the disconnected configuration.
15. The lifting machinery according to claim 14, comprising a distribution trolley movably mounted on the jib and linked to a distribution system adapted to displace the distribution trolley along the jib in opposite forward direction and backward direction, and wherein the lower reeve block hangs from said distribution trolley by the lifting rope.
16. The lifting machinery according to claim 14, wherein the lifting machinery is a crane.
17. A method for lifting a load in a lifting machinery, the lifting machinery comprising a jib and the double-reeved lifting device of claim 1 formed so as to lift/lower a load along the jib, wherein the lower reeve block hangs from the jib by a lifting rope connected to a lifting winch to make the lower reeve block ascend/descend, the lifting rope passing through the upper reeve block, the method comprising: connecting, in a connection phase for a switch from the disconnected configuration into the connected configuration, during which the lower reeve block is mounted for a relative approach between the two reeve blocks until the upper reeve block reaches a high stop on the jib and the bolt comes into the locking channel through the mouthpiece, slides inside the locking channel in the entry direction and exerts a push on the latch to bring the latch into a distal position until fitting inside the free end of the latch, and then the lower reeve block is displaced in descent so that the bolt slides inside the locking channel in the exit direction and brings the latch into a locking position, and thus the bolt is stuck inside the free end and sliding of the bolt in the locking channel in the exit direction is blocked, so that the lower reeve block is configured to descend with the upper reeve block in the connected configuration; and disconnecting, in a disconnection phase for a switch from the connected configuration into the disconnected configuration, during which the lower reeve block is raised until the upper reeve block reaches the high stop on the jib, and then the bolt slides inside the locking channel in the entry direction and brings the latch into an intermediate distal position, so that the bolt leaves the inside of the free end of the latch and afterwards the latch returns back into the neutral position by the effect of the elastic biasing element, and then the lower reeve block is displaced in descent so that the bolt slides inside the locking channel in the exit direction, pushes the latch towards a proximal position until coming out of the locking channel and being released from the latch, so that the lower reeve block is configured to continue descending in the disconnected configuration.
18. The lifting method according to claim 17, wherein the displacements of the lower reeve block, in the connection phase and in the disconnection phased, are automated.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Other features and advantages of the present disclosure will appear upon reading the detailed description hereinafter, of a non-limiting example of implementation, made with reference to the appended figures in which:
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DESCRIPTION
(15) Referring to
(16) This double-reeved lifting device 1 comprises two reeve blocks 3, 4, namely: a lower reeve block 3 secured to a lifting hook 30 intended to hook a load, wherein the lower reeve block 3 hangs from the distribution trolley 9 (and therefore hangs from the jib) by a lifting rope (not illustrated) connected to a lifting winch so as to make the lower reeve block 3 rise/descend; and an upper reeve block 4 through which the lifting rope passes, the upper reeve block 4 also hanging from the distribution trolley 9.
(17) Also, the lower reeve block 3 supports lower rope deflecting means, and the upper reeve block 4 supports upper rope deflecting means, such as for example a pulley 41, for the passage of the lifting rope. Thus, the double-reeved lifting device 1 is formed so as to lift/lower a load along the jib of the lifting machinery.
(18) The two reeve blocks 3, 4 are equipped with reversible connection means adapted to be reversibly configured between: a connected configuration (illustrated in
(19) Depending on the passage of the lifting rope in the lower rope deflecting means provided on the lower reeve block 3 and in the upper rope deflecting means provided on the upper reeve block 4, the connected configuration and the disconnected configuration respectively correspond to a double-reeved configuration and to a simple-reeved configuration, or vice versa, of the double-reeved lifting device 1; the simple-reeved configuration being associated to holding of the hook 30 (and therefore of the load) by two lifting strands of the lifting rope, and the double-reeved configuration being associated to holding of the hook 30 (and therefore of the load) by four lifting strands of the lifting rope.
(20) The reversible connection means comprise a locking mechanism 5 mounted on the lower reeve block 3, and a complementary locking structure 6 mounted on the upper reeve block 4 and adapted to cooperate with the locking mechanism 5.
(21) Referring to
(22) The upper reeve block 4 supports an upper stop 43 at the upper portion thereof, opposite to the mouthpiece 63 of the complementary locking structure 6. Moreover, the flanges 61 are brought away from each other at the level of the inlet 63, so that this inlet 63 is flared.
(23) Referring to
(24) The chassis 50 has a locking channel 53 having an elongated shape along the main axis (and therefore along a vertical direction), wherein this locking channel 53 is formed by two notches facing each other, formed in the two plates 51 and opening onto upper sears 510 of the plates 51, so that this locking channel 53 is provided with a mouthpiece 54 through which the bolt 62 of the complementary locking structure 9 could come in and come out of the locking channel 53. The mouthpiece 54 is flared so as to facilitate and center the insertion of the bolt 62 inside the locking channel 53.
(25) The bolt 62 has a cross-section dimensioned so as to be able to slide in the locking channel 53. The inner distance between the two flanges 61 of the frame 60 is larger than the thickness of the chassis 50, so that the chassis 50 could come into the groove of the frame 60 (and therefore between the two flanges 61) via the inlet 63, which is flared to facilitate this passage.
(26) Thus, the bolt 62 can slide in the locking channel 53 in an entry direction (downwards) and in an exit direction (upwards), opposite to the entry direction, respectively during a relative approach and distancing between the two reeve blocks 3, 4. It may be advantageous that the bolt 62 tightly slides (with a reduced clearance) inside the locking channel 53. This bolt 62 has a cylindrical section at a determined diameter. Thus, the locking channel 53 has a width substantially equivalent to the diameter of the bolt 62.
(27) The locking channel 53 has a bottom 55, which is located between the two pulleys 31, wherein this bottom 55 is adapted to stop sliding of the bolt in the entry direction. It should be noted that the two pulleys 31 are also rotatably mounted between the two plates 51.
(28) The two latches 52 are disposed facing each other on either side of the locking channel 53, and are pivotally mounted on the chassis 50, between the two plates 51, around parallel pivot axes; these pivot axes being also orthogonal to the main axis and also parallel to the longitudinal axis of the bolt 62. The two latches 52 are pivotable symmetrically with respect to a main plane including the main axis and parallel to the pivot axis of each of the two latches 52. The two latches 52 are identical and symmetrical with respect to the main plane.
(29) Each latch 52 is provided with a concave-shaped free end 56 adapted to be engaged with the bolt 62, wherein the free end 56 has an indentation 57 with a shape complementary to the bolt 62. Thus, the indentation 57 of the free end 56 of the latch 52 has a circle-arc shaped load-bearing area at a diameter equivalent to the diameter of the bolt 62. Each latch 52 is disposed between the mouthpiece 54 and the bottom 55 of the locking channel 53.
(30) For each latch 52, the indentation 57 of the free end 56 is delimited by two opposite sears 571, 572 on which the bolt 62 could exert a push, namely a proximal sear 571, facing the mouthpiece 54 of the locking channel 53, and a distal sear 572 facing the bottom 55 of the locking channel 53. Moreover, the proximal sear 571 and the distal sear 72 respectively have a proximal length and a distal length measured radially from the pivot axis, and the proximal length is smaller than the distal length.
(31) For each latch 52, the corresponding elastic biasing element 59 extends between the two plates 51 and has an end fastened to the latch 52, and another end fastened on the chassis 50. It should be noted that, in
(32) Each latch 52 is pivotally movable between: a neutral position (shown in
(33) As shown in
(34) The following description covers a disconnection phase for the switch from the connected configuration into the disconnected configuration, with reference to
(35) Referring to
(36) Referring to
(37) Referring to
(38) Referring to
(39) Thus, and as illustrated in
(40) The following description covers a connection phase for the switch from the disconnected configuration into the connected configuration, with reference to
(41) Referring to
(42) Referring to
(43) Referring to
(44) Thus, it should be noted that, in the connection phase and in the disconnection phase, only the control of the ascending/descending movements of the lower reeve block 3 allows switching from a connected configuration into the disconnected configuration, and vice versa. The control of the ascending/descending movements of the lower reeve block 3 is performed by controlling the lifting winch.
(45) Also, it may be advantageous to automate the displacements of the lower reeve block 3, in the connection phase and in the disconnection phase, by means of a monitoring/control unit which drives the lifting winch. In this context of an automation of the connection and disconnection phases, it may be advantageous to provide for one or several sensor(s) allowing detecting relative positions between the lower reeve block 3 and the upper reeve block 4, such as for example a sensor allowing detecting when the upper reeve block4 is at the high stop on the jib, and more specifically when the upper stop 43 of the upper reeve block 4 abuts against the distribution trolley 9. Indeed, this position represents a starting point of the movements that will follow in the connection and disconnection phases.
(46) Moreover, it could be considered to reverse the positions of the locking mechanism and of the complementary locking structure 6 of the reversible connection means, by arranging the locking mechanism 5 on the upper reeve block 4 and by arranging the complementary locking structure 6 on the lower reeve block 3. It is also possible to operate with one single latch 52 for the locking mechanism 5, by adapting the shape of the latch 52 to stick the bolt 62 in the locking channel 53. Alternatively, it is possible to operate with more than two latches 52 for the locking mechanism 5. It could also be considered to provide for elastic biasing elements 59 other than springs, such as for example elastic leaves, return mechanisms, or other equivalent means.