EP1928390B1

EP1928390B1 - Hoisting device for persons and clasp belonging thereto

Info

Publication number: EP1928390B1
Application number: EP06783975.3A
Authority: EP
Inventors: Wilhelmus Petrus Johannes De Kruijf; Jozef Huizinga
Original assignee: Joyincare Group BV
Current assignee: Joyincare Group BV
Priority date: 2005-09-20
Filing date: 2006-09-20
Publication date: 2014-12-31
Anticipated expiration: 2026-09-20
Also published as: WO2007035098A2; EP1928390A2; WO2007035098A3; NL1029988C2; DK1928390T3

Description

The invention relates to a hoisting device for persons, whereby the hoisting device is provided with a lever arm provided with a button having an enlargement, fastening means for fastening person-carrying means to the lever arm in a detachable fashion, whereby the carrying means are provided with straps, the ends of which are each attached to a clasp, whereby the clasps can each be attached to the lever button and whereby the clasps each have a recess, the smallest dimension of which is larger than the largest measurement of the enlargement of the button.
Such a hoisting device is known from EP-A-1 440 676 .
This known hoisting device requires the clasp to be shifted in two separate movements with respect to the button fastened to the lever arm, namely initially to move the button through the large opening of the clasp and then to move the button away from the large opening in the clasp through the connecting part of the clasp towards the small opening in the clasp and to interlock it there. Before the straps of the lift are tightened, it is still possible to easily undo the clasp if the relief worker does not actually move the clasp to the interlocked position. This may constitute a hazard during use. In such a situation, it is difficult for the guide to move the clasp in two separate directions as required by the prior art.
The object of the invention is to provide such a device whereby the attaching operation between the clasp and the lever can be carried out in one single movement. This ensures a safer application of the hoisting device for persons.
This object is achieved in that the clasp is provided with reducing means to reduce the surface area of the recess until said recess has the smallest dimension that is smaller than the enlargement of the button, but larger than or equal to the remaining part of the button.
As a result of these measures, only the button has to be positioned through the recess present in the clasp, which can take place in one movement in one single direction.
According to a first preferred embodiment, the recess is formed contiguous to an edge of the clasp and the reduced opening is closed by means of the reducing means. In this embodiment, the clasp is hooked onto the button in one movement in the direction of the principal plane of the clasp, after which the reducing means retain the button in the recess.
According to an embodiment excluding the above embodiment, the recess is surrounded on all its edges by a part of the clasp. In this configuration, the clasp is positioned around the button in one single movement in the direction transverse to the plane of the clasp and is then retained by means of the reducing means.
A further preferred embodiment provides for the measure that the reducing means comprise at least one retaining element that can be moved between a normal and reducing position. The at least one retaining element is more preferably movable in a direction parallel to the principal plane of the clasp. Although it is in principle possible to have a retaining body move in another direction, this leads to structural problems, in particular with respect to absorbing forces, particularly with respect to a narrow sizing of the clasp. By having the retaining element move in the direction parallel to the principal plane of the clasp, a simple construction will suffice.
The at least one retaining element is preferably attached to a spring that is arranged for pushing the at least one retaining element away from the normal position towards the reducing position. The retaining element is hereby pushed towards the button-retaining position so that the attachment between the clasp and the lever usually continues to be maintained. It is only possible to disconnect the clasp from the button by means of an active operation on the part of the user against the spring pressure.
The at least one retaining element is preferably attached to controlling means to move the at least one retaining element away from its reducing position towards its normal position when controlling the controlling means. This measure results in the controlling means having to be controlled not only when the button is inserted into the recess of the clasp, in other words when the carrying means are attached to the lever, but also when the carrying means are disconnected from the lever, thus increasing safety.
In a preferred embodiment, the at least one retaining element is arranged for guiding the button from a substantially unlocking state to an interlocking state. This makes it possible to easily bring the button into the interlocking state, in a way that will generally improve ease of use as well as the safety of the clasp according to the invention.
The at least one retaining element is preferably arranged in the reducing position to secure the button, which in turn counteracts the undesired disconnection of the button with respect to the clasp. To this end, the retaining element will usually be provided with a ridge to enable the button to be secured in the interlocking state of the clasp.
The hoisting device is preferably provided with interlocking means to interlock the at least one retaining element in the reducing position. It is thus possible to provide the clasp with an active interlock that interlocks the clasp in the reduced position.
A specific preferred embodiment provides for the measure that the at least one retaining element is provided with guiding means for carrying out a linear movement between the normal and reducing position with respect to the clasp. The guiding means are hereby configured in the form of linear guides that are relatively simple in structure.
According to yet another embodiment, the at least one retaining element is provided with guiding means for carrying out a rotational movement between the normal and reducing position with respect to the clasp. By providing a simple bearing, it is possible to provide such guiding means.
According to a structurally special measure, the hoisting device comprises two retaining elements that are arranged for together reducing the recess in their reducing position and comprise the controlling means for controlling levers that can move toward each other. In this way it is indeed easy to combine the controlling elements in the form of levers with the retaining elements.
A specific, structurally simple form of the invention provides for the measure that the opening is substantially circular and the diameter of the circle is greater than the diameter of the enlargement of the button.
Yet another preferred embodiment provides for the measure that the opening is substantially in the form of a large circle, whereby the diameter of the large circle is greater than the diameter of the enlargement of the button, wherein the large circle connects to a small circle partially coinciding therewith, wherein the diameter of the small circle is greater than the diameter of the narrow part of the button and whereby the center of the small circle lies within the large circle. This embodiment is advantageous in that the transverse forces exerted on the clasp by the button are not substantially absorbed by the retaining elements but by the body of the actual clasp.
In an alternative preferred embodiment, the diameter of a first part of the recess is larger than the diameter of the enlargement of the button, wherein the recess connects to a further recess, wherein the diameter of the further recess is larger than the diameter of the narrow part of the button and smaller than the diameter of the enlargement of the button, wherein the recess and the connecting further recess together have a substantially elongated form. The recess can thus be configured in an oval shape for example. More preferably, the diameter of a first extremity of the elongated recess is larger than the diameter of the enlargement of the button and the diameter of a second extremity of the elongated recess is larger than the diameter of the narrow part of the button and smaller than the diameter of the enlargement of the button. In a particular preferred embodiment, the recess is configured in a substantially conical (tapering) form, thus making it possible to provide a relatively efficiently shaped recess for connecting the button to the clasp according to the invention with relative stability and reliability and in a relatively simple manner.
A specific preferred embodiment provides for the measure that the clasp is arranged for emitting an audible noise, such as a click, when the recess is reduced. This is an audible confirmation for the user who is interlocking the clasp.
Further features of the invention will emerge from the accompanying non-restrictive drawings, in which the following are shown:

Figure 1: a view of a lever, to which two clasps according to the invention are attached with the carrying straps fastened thereto;
Figure 2: a view of a clasp according to a first embodiment;
Figure 3: a view of a clasp according to a variant of the first embodiment;
Figure 4: a view of a clasp according to a second embodiment;
Figure 5: a view of a clasp according to a variant of the second embodiment;
Figure 6: a view of a clasp according to another variant of the second embodiment;
Figure 7: a view of a clasp according to a third embodiment;
Figure 8: a view of a clasp according to a variant of the third embodiment;
Figure 9: a view of a clasp according to a fourth embodiment;
Figure 10: a view of a clasp according to a fourth embodiment;
Figure 11: a view of a clasp according to a variant of the fourth embodiment;
Figure 12a: a three-dimensional view of another clasp according to the invention in an interlocking state;
Figure 12b: a three-dimensional, cut-away view of the clasp according to Figure 12a;
Figure 12c: a three-dimensional view of the clasp according to Figure 12a in an unlocking state;
Figure 13: a schematic top view of an alternative clasp according to the invention;
Figure 14a: a schematic top view of yet another clasp according to the invention;
Figure 14b: a schematic side view of the clasp according to Figure 14a;
Figure 15a: a schematic top view of yet another clasp according to the invention;
Figure 15b: a schematic side view of the clasp according to Figure 15a in an unlocking state; and
Figure 15c: a schematic side view of the clasp according to Figure 15a in an interlocking state.

The invention is applicable for lifting devices such as those used when helping persons requiring assistance to sit down and stand up. An example of such a lifting device is described in Dutch patent application 1024909 .
Such a device comprises a carrying unit produced out of a flexible material, in which the person requiring assistance is seated. This carrying unit can be connected to a lever 2 by means of a number of straps 1. The lever 2 is arranged for carrying out a movement supporting the movement of the person requiring assistance. The ends of the straps 1 and the lever are attached by means of clasps 3 that can be attached to buttons 4 affixed to the lever. These buttons 4 each comprise an enlargement 5 and a narrow part 6 with which the enlarged part is fastened to the lever 2.
Figure 2 shows a first embodiment of such a clasp according to the invention. This clasp indicated in its entirety by the number 3 comprises a substantially flat sheet 7, in which an opening 8 is made. At one end, an elongated opening 9 is made in the sheet 7, which is used to connect to a strap 1. Instead of the elongated opening 9, other connecting means can also be used. The opening 8 is circular in the present example and the diameter thereof is slightly greater than that of the enlargement 5 of the button 4, so that the button 4 can be inserted into the opening 8.
A retaining sheet 10 indicated by the shading in Figure 2 extends parallel to the sheet 7 and can be moved parallel to the sheet 7. To this end, guiding means are provided, facilitating a movement in the vertical direction in the drawing. A circular opening 11 is made in the retaining sheet 10 having substantially the same dimensions as those of the opening 8 in the sheet 7. The retaining sheet 10 is pushed towards the position shown in Figure 2 by means of two springs 12. It should be noted that other types of springs could be used. The two openings 8 in the sheet 7 and 11 in the retaining sheet 10 partially coincide in the position shown in the drawing. The resultant opening in this assembly has a smallest dimension that is smaller than the diameter of the enlargement 5 of the button 4, but greater than the diameter of the narrow part 6 of the button 4. The retaining sheet 10 protrudes from the sheet 7 in the position shown in Figure 2.
Such a clasp is used as follows: a strap 1 is connected to the clasp by means of the elongated opening 9. If the position of the person requiring assistance has to be changed using the hoisting device and the carrying unit is attached to the person requiring assistance, the carrying unit has to be connected to the lever 2 by attaching the clasp 3 to one of the mushroom-shaped buttons present on the lever 1. To this end, the user pushes the protruding part of the retaining sheet 10 inwards, against the spring pressure of the springs 12, until the openings 7 and 11 coincide. The user then positions the clasp 3 with the coincident openings 7 and 11 over the button 4, until the enlargement 5 of the button 4 passes over the opening and the narrow part extends through the opening. The user then lets go of the retaining sheet 10, after which the position shown in Figure 2 will be achieved due to the spring pressure. The button 4 is then retained in the opening 7 and 11 by means of form retention.
It should be noted that there are many possible variations of this embodiment. For instance, it is possible to provide the sheet 7 with a groove in which the retaining sheet 11 can be moved. Otherwise means are required, as with the described embodiment, to restrict the movement of the sheets.
A variant is shown in Figure 3, whereby the geometry has been adjusted. Instead of a retaining sheet 11, this embodiment is provided with two retaining segments 13 that are both connected to the sheet 7 via the same hinge 16. The retaining segments 13 both enclose a circular opening 14, the diameter of which is smaller than that of the enlargement 5 of the button 4, but greater than that of the narrow part 6 of the button 4. The retaining segments 13 each comprise a controllable lever 15. The retaining segments 13 are pushed into the position shown in Figure 3 by means of a spring 12.
This embodiment can also be attached to the button 4 by means of form retention. To this end, the opening 14 is initially increased to opening 8 by pressing the levers 13 together, after which the clasp can be moved over the broad part of the button and then the levers are released to engage with the narrow part of the button.
Figure 4 shows yet another embodiment, whereby, as with the embodiment shown in Figure 2, a retaining sheet 17 is used, but with the retaining sheet 17 being connected to the sheet 7 in a rotatable fashion around a pin 18. In this embodiment as well, an opening 19 is made in the retaining sheet 17. A spring 20 is also incorporated for pushing the retaining sheet 17 towards the position shown in Figure 4.
With the embodiment hitherto described and variations thereof, the openings are always circular; with the second embodiment, as shown in Figure 5, an opening 22 is formed in the sheet 7 having the form of two partially coinciding circles of unequal size, there being no restriction or parallel slot present between both circles. The advantage of this embodiment compared with the embodiment initially referred to is the fact that the forces are directly absorbed by the sheet 7. A large part of the circumference of the coincident opening 22, 11 is indeed formed by the sheet 7. For the rest, this embodiment functions in the same way as the first embodiment.
Figure 6 shows a variant of the embodiment shown in Figure 5, whereby, as with the variant shown in Figure 3, retaining segments 23 are affixed in a rotatable fashion. It should be noted here that the opening 14 between the retaining segments 23 that are pushed towards each other coincides with the small circle forming part of opening 22.
As with the variant shown in Figure 4, the variant of the second embodiment shown in Figure 7 is provided with a retaining sheet 17 that is connected to the sheet 7 in a rotatable fashion around a pin 18. The only difference in the two variants lies in the geometry of the opening 22.
Figure 8 shows a third embodiment, whereby the sheet and the retaining sheet are each substantially of the same design, thus achieving a symmetrical configuration. This embodiment therefore comprises two sheets 25, 26 that are a mirror image of each other and that are each provided with an opening 29 in the form of two partially coinciding circles. The sheets 25, 26 are interconnected in a hinged fashion by means of a hinge 27, also forming the connection to a fastening sheet 28, in which an elongated opening 9 is made to fasten the strap. Both sheets are pushed towards each other to form the position shown in Figure 8 by means of a spring that is not shown in the figure. To affix the clasp, the sheets are moved towards each other against the spring pressure, causing the large circles of the openings to coincide with each other and the clasp to slide over the broad part of the button.
The embodiment shown in Figure 9 largely corresponds to the embodiment shown in Figure 5, provided that not only is the sheet provided with two elongated openings for the strap, but also the geometry of the openings is different with respect to the direction of movement of the retaining sheet 10.
Figure 10 shows an embodiment, whereby the recess in the sheet is not configured in the form of an opening as with the previous embodiment, but is actually configured in the form of a notch in the sheet. This embodiment therefore comprises a sheet 30, in which an elongated opening 9 is made to fasten the strap 1. The sheet is provided with a recess 31 that is sufficiently large to accommodate the narrow part 6 of the button 4. The sheet can be slid with the recess simply over this button 4. To interlock the clasp on the button 4, the clasp is provided with a substantially U-shaped rotatable retaining sheet 32. This retaining sheet 32 is fastened onto the sheet 30 in such a way that the retaining sheet 32 can be rotated around one part of the recess 31, being the part that can accommodate the narrow part 6 of the button 4. As a result of these measures, the retaining sheet 31 can be rotated with the opening of the U coinciding with the opening of the recess 31. The clasp can then be slid over the button. The retaining sheet 32 can then be rotated back again to a position in which it retains the narrow part 6 of the button. A spring is preferably provided to push the retaining sheet 32 towards this retaining position and the user has to press against the spring pressure of this spring in the retaining sheet towards the opened position for the clasp to hook onto the button.
Figure 11 shows a variant of this embodiment, whereby the retaining sheet 34 can be shifted by means of a longitudinal movement rather than a rotational one. As with the previous embodiment, the retaining sheet is pushed towards the recess-closing position by means of a spring not shown in the drawing. The retaining sheet 34 can be moved against the spring pressure into the opening-releasing position by means of a manually controlled slide valve 35, as in the embodiment shown in Figure 10.
Figure 12a shows a three-dimensional view of a clasp 36 according to the invention in an interlocking state, comprising a sheet 37 structured out of two congruent parts 37a, 37b, and a closing element 38 connected to the sheet in a slidable fashion. The sheet 37 is provided with a substantially conical feedthrough opening 39 for a button (not shown). As shown in Figures 12a to 12c, the closing element 38 can be moved in a direction that is substantially perpendicular to the longitudinal axis of the conical feedthrough opening 39. In the interlocking state, as shown in Figure 12a, the feedthrough opening 39 is partially screened off by the closing element 38. The closing element 38 is stabilized in the interlocking state by means of two springs 40a, 40b (see Figure 12b), which is advantageous from a safety point of view. By manually moving the closing element 38 relative to the sheet 37, it is possible to open up the feedthrough opening 39 (see Figure 12c), enabling a button to be removed from the clasp 36 or placed in the feedthrough opening 39. This unlocking state is relatively unstable, as a user has to forcibly hold the closing element 38 in the unlocking state in order to maintain the unlocking state. When the closing element 38 is released, the closing element 38 will move back to the interlocking state as a result of the present spring pressure, as shown in Figure 12a. Figure 12a also shows that the single feedthrough opening 39 is screened off in selective places by the closing element 38, causing the feedthrough opening 39 to be divided de facto into an interlocking opening part 39a, and a quasi-stable opening part 39b. In this way, the closing element 38 also functions as a guide for guiding a button located in the quasi-stable opening part 39b towards the (more stable) interlocking opening part 39a, so that the button can be secured and thus stabilized. In the quasi-stable opening part 39b, the button will generally still be interlocked, although usually not in a stable and satisfactory manner. The sheet 37 is also provided with a double feedthrough 41a, 41b for a strap (not shown) of a hoisting device.
Figure 13 schematically shows a top view of an alternative clasp 42 according to the invention. The clasp 42 furthermore comprises a sheet 44 provided with a single elongated, conical recess 43, and a closing element 45 connected to the sheet 44 in a slidable fashion. The actual size of the recess 43 can be adjusted using the closing element 45. The closing element 45 can thus be moved in a direction substantially parallel to the longitudinal axis of the conical recess 43 (see arrow A).
Figures 14a and 14b schematically show a top view and a side view respectively of another clasp 46 according to the invention. The clasp 46 comprises a base sheet 48 provided with a conical recess 47, and a closing sheet 50 connected to the sheet 48 in a swiveling fashion by means of a hinge 49. The recess 47 is arranged in particular for feeding through a lever button (not shown), and in particular a button provided with an enlarged extremity having an elongated cross-section, and thus to a lesser extent for feeding through an enlarged extremity having a circular cross-section (mushroom-shaped). By swiveling the closing sheet 50 relative to the base sheet 48 (see arrow B), it is possible to adjust the actual size of the recess 47, so that the button can interlock or unlock with respect to the clasp 46.
Figure 15a schematically shows a top view of yet another clasp 51 according to the invention. The clasp 51 comprises a sheet 52 provided with a recess 53 for feeding through a button 54. The recess 53 is formed by a small circular recess 53a and a large circular recess 53b. In this way, the large circular recess 53b acts as a feedthrough opening for the button, and the small circular recess 53a acts as a receptacle for the button when the clasp 51 is in an interlocking state (see Figure 15c). The clasp 51 also comprises a partition 55 working in conjunction with the sheet 52, said partition 55 being able to move in a direction that is substantially perpendicular to a plane fixed by the sheet 52 (see arrow C). In the exemplary embodiment shown, the partition 55 lies entirely in the large circular recess 53b, and is arranged for interlocking the button 54 in the small circular recess 53a. As shown in Figures 15b and 15c, the partition 55 is also provided with a recess 56 for feeding through - if possible - a button 54. Figure 15b shows the partition 55 in an unlocking state, in which it is possible to move the button 54 between the small circular recess 53a and the large circular recess 53b. Figure 15c shows the partition 55 in an interlocking state, in which the button 54 is interlocked in the small circular recess 53a.
It should be noted that numerous variations of the embodiments shown herewith can be applied, without departing from the scope of the invention. In particular it is possible for the measures of the various embodiments to be combined.

Claims

Hoisting device for persons, comprising:
- a lever arm provided with a button (4) having an enlargement;

- fastening means for fastening person-carrying means to the lever arm in a detachable fashion,

- whereby the carrying means are provided with straps (1), the ends of which are each attached to a clasp (3, 37),

- whereby the clasps (3, 37) can each be attached to the button (4), and

- whereby the clasps each have a recess (8, 14, 22, 31, 39, 53), the smallest dimension of which is larger than the largest measurement of the enlargement (5) of the button (4), characterized in that the clasp (3, 37) is provided with reducing means (10, 11, 13, 17, 23, 25, 30, 34, 45, 50) to reduce the surface area of the recess (8) until it has the smallest dimension that is smaller than the enlargement (5) of the button (4), but larger than or equal to the remaining part (6) of the button (4).
Hoisting device according to claim 1, characterized in that the recess (8, 14, 22, 31, 39, 53) is formed contiguous to an edge of the clasp (3, 37) and in that the reduced opening is closed by means of the reducing means (10, 11, 13, 17, 23, 25, 30, 34, 45, 50).
Hoisting device according to claim 1, characterized in that the recess (8, 14, 22, 31, 39, 53) is surrounded on all sides by a part (7, 25, 26, 30, 37, 44, 48, 52) of the clasp (3, 37).
Hoisting device according to any one of the preceding claims, characterized in that the reducing means (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) comprise at least one retaining element (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) that can be moved between a normal and a reducing position.
Hoisting device according to claim 4, characterized in that the at least one retaining element (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) can be moved in a direction substantially parallel to the principal plane of the clasp (3, 37) between a normal and a reducing position.
Hoisting device according to claim 4 or 5, characterized in that the at least one retaining element (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) is attached to at least one spring (12, 20) that is arranged for pushing the at least one retaining element (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) away from the normal position towards the reducing position.
Hoisting device according to any one of claims 4 to 6, characterized in that the at least one retaining element (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) is attached to controlling means for moving the at least one retaining element (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) away from its reducing position towards its normal position when the controlling means are controlled.
Hoisting device according to any one of claims 4 to 7, characterized in that the at least one retaining element (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) is arranged for guiding the button (4) from a substantially unlocking state to an interlocking state.
Hoisting device according to any one of claims 4 to 8, characterized in that the at least one retaining element (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) in the reducing position is arranged for securing the button (4).
Hoisting device according to any one of claims 4 to 9, characterized by interlocking means for interlocking the at least one retaining element (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) in the reducing position.
Hoisting device according to any one of claims 4 to 10, characterized in that the at least one retaining element (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) is provided with guiding means for carrying out a linear movement between the normal and reducing position with respect to the clasp (3, 37).
Hoisting device according to any one of claims 4 to 10, characterized in that the at least one retaining element (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) is provided with guiding means(16, 18, 27) for carrying out a rotational movement between the normal and reducing position with respect to the clasp (3, 37).
Hoisting device according to claim 12, characterized in that the hoisting device comprises two retaining elements (10, 11, 13, 17, 32, 34, 38, 45, 50, 55) that are arranged for together reducing the recess (8, 14, 22, 31, 39, 53) in their reducing position and comprise the controlling means for controlling levers that can move towards each other.
Hoisting device according to any one of the preceding claims, characterized in that the recess (8, 14, 22, 31, 39, 53) is substantially circular and in that the diameter of the circle is greater than the diameter of the enlargement (5) of the button (4).
Hoisting device according to any one of the preceding claims, characterized in that the recess (8, 14, 22, 31, 39, 53) is substantially in the form of a large circle, whereby the diameter of the large circle is greater than the diameter of the enlargement (5) of the button (4), wherein the large circle connects to a small circle partially coinciding therewith, wherein the diameter of the small circle is greater than the diameter of the narrow part of the button (4) and whereby the center of the small circle lies within the large circle.
Hoisting device according to any one of the preceding claims, characterized in that the diameter of an extremity of the elongated recess (8, 14, 22, 31, 39, 53) is larger than the diameter of the enlargement (5) of the button (4) and, wherein the recess (8, 14, 22, 31, 39, 53) connects to a further recess, wherein the diameter of an extremity of the further recess is larger than the diameter of the narrow part (6) of the button (4) and smaller than the diameter of the enlargement (5) of the button (4), wherein the recess (8, 14, 22, 31, 39, 53) and the connecting further recess together have a substantially elongated form.
Hoisting device according to claim 16, characterized in that the recess (8, 14, 22, 31, 39, 53) is configured in a substantially conical form.
Hoisting device according to any one of the preceding claims, characterized in that the clasp (3, 37) is arranged for emitting an audible noise, such as a click, when the recess (8, 14, 22, 31, 39, 53) is reduced.
Clasp (3, 37) according to any one of the preceding claims for use with a hoisting device according to any one of the preceding claims.