WO2011137908A1

WO2011137908A1 - Lifting tool

Info

Publication number: WO2011137908A1
Application number: PCT/DK2011/050152
Authority: WO
Inventors: Thomas Steffensen
Original assignee: Locco Aps
Priority date: 2010-05-04
Filing date: 2011-05-03
Publication date: 2011-11-10
Also published as: EP2566674A1; DK177211B1; EP2566674A4; DK201070185A

Abstract

A lifting tool for lifting composite items, for example moulds for injection moulding, consisting of two or more parts brought to an assembled position, where the lifting tool is arranged with means for fixing to the composite item and including at least a first arm and a second arm, where the arms are mutually displaceable for adaptation to a specific composite item, and where the arms are further connected with a lifting eyelet where both the first and the second arms include means for fastening the item, and which is peculiar in that the first and second arms are connected to a body, where the body forms a lifting yoke with a lifting eyelet, and where the first and the second arms, respectively, are individually movable in relation to the body.lifting tool

Description

Lifting Tool

Field of the Invention

The present invention concerns a lifting tool for lifting composite items, for example moulds for injection moulding, consisting of two or more parts brought to an assembled position, where the lifting tool is arranged with means for fixing to the composite item and including at least a first arm and a second arm, where the arms are mutually displaceable for adaptation to a specific composite item, and where the arms are further connected with a lifting eyelet, where both the first and the second arms include means for fastening to the item.

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Background of the Invention

By moulding plastic articles, two-part injection moulding moulds are typically used. In a production line it will be normal to mould different plastic articles, and the moulds are therefore replaced with other moulds for other articles from time to time. In some cases, the moulds are to be replaced up to several times a day. The moulds are typically made of metal/steel and frequently weigh several hundreds of kilos, and are often expensive to make. Therefore, it is important to protect the moulds during replacement while at the same time making allowance for the safety of the persons performing the replacement of the mould.

By replacing a mould, the two parts are lifted out simultaneously in order to protect the mould. The two moulds are held together, either by the lifting tool or by some assembling members mounted thereon which keep the mould together during lifting action.

The problem of mounting assembling members in order to keep the mould together is that it is easy to forget to dismount them again before the tool is put into operation. If the tool is put into operation with assembling members mounted and still sitting on the tool, both the parts and the mould, possibly also the injection moulding machine, will be damaged. Furthermore, there is a risk of injury if the assembling member should break. If there are no external means keeping the mould together during lifting, the two parts will tend to slide apart. This is not desirable as damage may occur on the mould. The present lifting tools for moulds consist of two parts that are displaceable in relation to each other in order to be adjusted to the mould to be lifted. The lifting tool is displaceable as the moulds in practice cannot have identical spacing between holes for mounting a lifting tool. In order to ensure that the two parts in the lifting tool are not displaced during lifting, they are joined by a clamping member which at the same time is connected to a lifting eyelet. This entails considerable disadvantages. Namely that there is a risk that the two mould parts slide away from each other if the clamping member is not properly tightened. Which means that tightening is typically performed excessively and that the lifting tool is worn unnecessarily thereby. Moreover, it has the drawback that the lifting eyelet is rotated during tightening of the clamping member, meaning that the lifting chain used for lifting and holding the lifting tool is to be dismounted if the lifting tool is to be adjusted.

DE 85 09 642 U discloses a lifting tool consisting of a plurality of loose parts which can be mounted on a mould tool. By this solution, a little compensation can be made for imbalance in the mould tool. However, there is the inexpediency that the lifting tool comprises many loose parts that are to be stored and handled during application of the tool. The fact that there are many loose parts to be handled entails a longer time for mounting and dismounting, but also an increased risk that the tool is not mounted as prescribed. Furthermore, there is only little opportunity for correcting the position of the lifting tool on the mould tool and therefore it is not always possible perform lifting above the point of gravity by which the most secure and controlled lifting is achieved. Besides, also by the present lifting tools there is a great risk of the user getting squeeze injuries by mounting and adjusting the lifting tool. Such injuries can be serious and may in some cases cause a user to have a crushed finger or finger part, for example. Object of the Invention

It is the object of the invention to indicate a lifting tool for composite items, such as moulds for injection moulding, where the lifting tool overcomes the mentioned disadvantages and improves personal safety. At the same time, it is an object to indicate a lifting tool where there are better opportunities for performing more optimal and straight lifting actions.

Description of the Invention

This is achieved by a lifting tool for lifting composite items of the type mentioned in the introduction which is peculiar in that the first and second arms are connected to a body, where the body forms a lifting yoke with a lifting eyelet, and where the first and the second arms, respectively, are individually movable in relation to the body.

In that the arms are individually movable in relation to the body and not only in relation to each other, the arms can be adjusted to many different positions, and thereby the lifting tool can be used for a number of different moulding tools. Furthermore, the arms are individually adjustable in relation to the lifting eyelet. This implies that the arms can be adjusted and fastened to the composite item while at the same time the lifting tool is attached to a chain or wire from a crane. The fastening of the lifting tool to the item is thereby considerably facilitated for the person mounting the lifting tool.

The arms will typically be movable in a groove adapted for the purpose in the body. The arms can be mounted in each their groove, or they can share the same groove.

According to a further embodiment, the lifting tool is peculiar in that the lifting tool includes locking means, and where the first and second arms are locked in relation to the body at individual positions by activating the locking means. Hereby is achieved that the arms are locked in relation to the body, and it is thereby ensured that an item is held together when the item is lifted. According to a further embodiment, the lifting tool is peculiar in that for locking the first and the second arm, the locking means are activated by lifting the composite item.

In that the locking means are activated by lifting the composite item on which the lifting tool is applied, it is safeguarded that the two parts of the composite item do not force the arms away from each other, and thereby it is achieved that the composite item is not damaged.

In a preferred embodiment, the locking means and the automatic activation are realised by arranging the body with a groove such that each arm has one, preferably two flanges arranged inside the groove so that the arms are movable in the groove in relation to the body. The flange and the groove are furthermore adapted with a given tolerance such that the flange can capsize in relation to the groove and thereby lock the arms. The arms are arranged such that the fastening means for the item and the position of the flanges in the groove have a certain horizontal spacing where the lifting direction is regarded as being vertical.

Hereby is achieved that when the item is lifted, the item will act on the arm with a force which due to the horizontal distance will make the flanges capsize and thereby lock the arm in relation to the body. This is particularly advantageous as the operator of the lifting tool does not need to worry about whether the composite items is maintained in assembled position since this occurs automatically as soon as lifting of an item is initiated. In order to ensure that the flanges capsize in relation to the body, either the flanges or the arm itself close to the means for fastening a composite item can be angled in relation to the groove. The arm and the flange will thereby be forced to capsize when the arm is fastened to the composite item, and thereby it is further ensured that the arms are locked in relation to the body under lifting action.

According to a further embodiment, the lifting tool is peculiar in that the lifting eyelet is provided with a base, the base being movable in relation to the body in a cutout in the body. In that the lifting eyelet is connected to the body via a base, and that the base is movable in relation to the body, it is achieved that the lifting eyelet can be moved relative to the body without changing orientation. This contributes to making it unnecessary to dismount a possible chain or wire connected to the lifting eyelet in order to adjust the position of the lifting eyelet.

By adjusting the lifting eyelet it is further achieved that it can be controlled where lifting is performed as seen in relation to the composite item. The lifting eyelet may thereby be adjusted such that the lifting occurs at a point where the weight of the item is more or less centralised in relation to the lifting eyelet. Hereby it is ensured that the item does not tilt during lifting action. It is thus about a controlled lifting in relation to lifting performed with the prior art types of lifting tools. According to a further embodiment, the lifting tool is peculiar in that via interacting locking means in the body and at the base of the lifting eyelet, the lifting eyelet can be locked in relation to the body.

In that the position of the lifting eyelet can be locked in relation to the body it is ensured that the lifting eyelet does not move during lifting, and the lifted item is thereby secured against tilting.

According to a further embodiment, the lifting tool is peculiar in that the interacting locking means for locking the lifting eyelet are activated by lifting in the lifting eyelet.

Hereby is achieved the advantage that it is ensured that the locking means are activated. This is a great advantage as the user of the tool therefore does not need to worry about whether the lifting eyelet is locked or not. In a preferred embodiment, the locking means are constituted by a number of pins/depressions along the cutout in the body, where the base of the lifting eyelet has one or more corresponding depressions/pins. By lifting in the lifting eyelet, depressions and pins will automatically seek other and thereby lock the lifting eyelet in relation to the body. In order to move the lifting eyelet, it is required that it is pushed towards the body in order thereby to release pins and depressions from each other so that the base can move in the cutout again. This also ensures that the lifting eyelet is not moved or displaced relative to the body by accident.

According to a further embodiment, the lifting tool is peculiar in that the means for fastening the composite item include a threaded rod arranged in each of the first and second arms, respectively, the threaded rod extending through at least part of respective arms.

In most moulds one or more holes with screw thread are arranged. Therefore it is an advantage that the lifting tool has a corresponding threaded rod for fixed mounting to a mould. The threaded rod may advantageously extend through part of an arm in order to retain the threaded rod to the arm such that the threaded rod cannot be dismounted from the arm. This may be ensured by mounting a lock ring or similar in a recess on the threaded rod, the lock ring engaging means adapted for the purposed in the arms of the lifting tool.

In a variant of a lifting tool according to the invention, the threaded rod can be provided with a spring element by which it is ensured that the threaded rod is always in a lifted position when not engaging the corresponding thread in a mould. This provides a general advantage as the screw thread on the threaded rod is protected against impacts in this way. By such a variant, the threaded rod has no tendency either to fall into other openings and/or recesses in the mould during mounting of the lifting tool, as the threaded rod is only pressed down and brought to engage when the lifting tool is in position above the correct threaded holes in the mould.

According to a further embodiment, the lifting tool is peculiar in that the lifting tool includes one or more indicators for indicating that one or more of the means for fastening to the item are correctly fastened to the item.

Hereby is achieved that it is always indicated whether the lifting tool is mounted correctly on the item or not. This ensures that the composite item is held secured to the lifting tool during lifting action. Furthermore, it is ensured that the fixing means are not excessively tightened and thereby unnecessarily wear on the screw thread in the composite item and on the lifting tool. The indicators may e.g. be in the form of a visual marking on the threaded rod and the arm, respectively, such that when the two markings are opposite each other, the threaded rod has been screwed sufficiently down into a corresponding threaded hole in the composite item. The visual marking may also be designed such that it can be read how much the threaded rod is screwed into the item.

According to a further embodiment, the lifting tool is peculiar by including means arranged in the body for maintaining a minimum spacing between the first arm and the second arm. Hereby is achieved that the arms cannot be completely brought together, and the user of the lifting tool is therefore safeguarded against getting limbs pinched or squeezed in the lifting tool.

The means can be in the form of a physical blockage of the groove to which the arms are fixed. This blockage may be fixed or movable in the groove, or alternatively with more grooves in each their arm.

The means can also be in the form of a special shape of the flange of the arm engaging the body. This flange which is surrounded by the body may be of such extent and design that two flanges from two arms can be in contact without the arms outside the body being in contact with each other. The visible part of the arms will hereby maintain a mutual minimum spacing, and personal security is therefore improved as compared with existing lifting tools. According to a further embodiment, the lifting tool is peculiar in that the lifting tool further includes one or more arms in connection with the body, where each additional arm is displaceable for adapting to a specific composite item, and where each additional arm includes means for fastening to the composite item. If an item is composed of many parts or require lifting at several points, the lifting tool may include an additional number of arms. If an assembled element is in three parts, the body can be arranged as a triangle where one arm per side is movably arranged at each their side. Other designs of the body and the mobility of the arms relative to the body can be arranged according to need.

Description of the Drawing

The invention is described in the following with reference to the drawing, wherein: Fig. 1 shows the lifting tool 1 in an isometrical view.

Fig. 2 shows the lifting tool 1 from the front.

Fig. 3 shows the lifting tool 1 from the front with a different position of the lifting eyelet.

Fig. 4 shows the lifting eyelet.

Fig. 5 shows the body from below.

Fig. 6 shows a threaded rod.

Fig. 7 shows an arm.

Fig. 8 shows a cross-section of the body as seen from the side.

Fig. 9 shows a cross-section of the body as seen from the side with the lifting eyelet in locked position.

In the explanation of the Figures, identical or corresponding elements will be provided with the same designations in different Figures. Therefore, no explanation of all details will be given in connection with each single Figure/embodiment. Detailed Description of Embodiments of the Invention

Fig. 1 shows a lifting tool 1 in isometrical perspective view. The lifting tool 1 includes a body 2 with an upper part 25 and with a lower part 26 which is connected with a movable first arm 3 and a movable second arm 4 which is here shown in the outermost position relative to the body 2. The lifting tool 1 furthermore includes a lifting eyelet 5 which is connected to the body 2 via movable base 6. A threaded rod 7 partially going through the arms 3, 4 is provided for fixing the lifting tool 2 to an item (not shown). The threaded rod 7 includes an indicator 8 which together with an edge 9 on the arms 3, 4 indicate how much the threaded rod 7 is screwed into an item. The threaded rod 7 further includes a device 21 for engaging with a clamping tool which in the shown embodiment is made as a bolt head 21. The lifting tool 1 further includes a type data plate 10 on which information about production date, date of use, lifting capability etc. can be printed.

Fig. 2 shows the lifting tool 1 as seen from the front. The lifting tool 1 is shown where the arms 3, 4 are at the innermost position relative to the body, and where the spacing between the arms 3, 4 is limited tot his with means adapted therefore(not shown).

It is seen on the Figure that the threaded rod 7 is in its upper position as the lower part 22 of the indicator 8 is opposite the edge 9, and the screw thread 11 on the threaded rod 7 is just visible at the bottom of the arms 3, 4. In the shown embodiment, the threaded rod 7 will be screwed to the bottom when the upper part 23 of the indicator is opposite the edge 9.

In connection with the lifting eyelet 5, there is furthermore an eyelet 12 to which may easily be attached a label (not shown) with e.g. inspection data and other information which is expected to be replaced continuously, and therefore not suited for printing on the data plate 10.

Fig. 3 shows the lifting tool 1 in the same embodiment as in Fig. 2 where the lifting eyelet 5 is in an extreme position relative to the body 2. As the lifting eyelet 5 is movable independently of the arms 3, 4, compensation for the uneven weight distribution between the two parts of the composite element (not shown) and thereby straight lifting is achieved.

Fig. 4 shows the lifting eyelet 5. The lifting eyelet 5 is connected to a base 6. The base includes pins 13 for engaging the body (not shown) for locking the lifting eyelet 5.

Fig. 5 shows the upper part 25 of the body 2 as seen from below. Here it appears that the body 2 has a cutout 14 corresponding to the base 6 (see Fig. 4) of the lifting eyelet 5 (not shown). In the cutout 14 is arranged a number of depressions 15. The depressions 15 are arranged such that the pins 13 (see Fig. 4) can engage the former and thereby lock the base 6 in relation to the upper part 25 of the body 2 and thereby lock the lifting eyelet 5 (not shown). Fig. 6 shows a threaded rod 7. The threaded rod includes a bolt head 21, an indicator 8, a screw thread 11 and a bead 16. The bead is arranged such that when the threaded rod is mounted partially through-going in an arm 3, 4 (not shown), the bead 16 will prevent the threaded rod 7 from being separated from the arm 3, 4 (not shown). A cutout is made in the arm 3, 4 corresponding to the bead 16, allowing the threaded rod 7 to be moved a given length in axial direction relative to the arm 3, 4.

Fig. 7 shows an arm 18. The shown arm 18 is symmetric and may thereby be used as first and second arm 3, 4, respectively. The arm 18 has a through-going cutout 17 in which a threaded rod 7 (not shown) can be fitted. The cutout 17 is designed such that inside the arm 18 is formed a cavity where a bead 16 (see Fig. 6) on a threaded rod 7 (not shown) can move freely in axial direction of the threaded rod and turn about its axis simultaneously with the threaded rod 7 (not shown) cannot be separated from the arm 18. The arm 18 further has an additional cutout 19 forming a flange 20 such that the arm 18 can be mounted for moving in a groove 24 (see Fig. 8) in the lower part 26 of the body 2 of the lifting tool 1 (not shown).

Fig. 8 shows a cross-section of the body 2 as seen from the side where the upper part 25 and the lower part 26 appear. In the upper part 25 appears a cutout 14 in which is arranged depressions 15.

As mentioned, the body also includes a lower part 26 with a groove 24 for receiving a flange 20 from an arm 18 (only partly in the form of the flange). It can be seen that the groove 24 is with a width less than the cutout 19 which forms the flange 20. Thus there is an allowance between flange 20 and body 2, and the flange 20 may therefore capsize relative to the body 2 and thereby become wedged, and hereby the arm 18 will become locked for displacement in relation to the body 2. In principle, Fig. 9 shows the same cross-section as in Fig. 8, but here in a situation where the lifting eyelet 5 is provided in a locked position in upper part 25 of the body 2. The body 6 is provided in the cutout 14, and the pins 13 on the base 6 engages the depressions 15. The lifting eyelet 5 is locked hereby. The lifting eyelet 5 is brought back into movable condition in that the pins 13 are pushed out of the depressions 15 whereby the base 6 can move freely along the cutout 14. The lower part 26 of the body 2 is shown here without the groove 24.

Claims

1. A lifting tool (1) for lifting composite items, for example moulds for injection moulding, consisting of two or more parts brought to an assembled position, where the lifting tool (1) is arranged with means (3, 4, 7) for fixing to the composite item and including at least a first arm (3) and a second arm (4), where the arms (3, 4) are mutually displaceable for adaptation to a specific composite item, and where the arms (3, 4) are further connected with a lifting eyelet (5), where both the first and the second arms (3, 4) include means (7) for fastening to the item, characterised in that the first and second arms (3, 4) are connected to a body (2), where the body (2) forms a lifting yoke with a lifting eyelet (5), and where the first and the second arms (3, 4), respectively, are individually movable in relation to the body (2).

2. Lifting tool (1) according to claim 1, characterised in that the lifting tool (1) includes locking means (19, 20, 24), and where the first and second arms (3, 4, 18) are locked in relation to the body (2) at individual positions by activating the locking means (19, 20, 24).

3. Lifting tool (1) according to claim 2, characterised in that for locking the first and the second arm (3, 4, 18), the locking means (19, 20, 24) are activated by lifting the composite item.

4. Locking tool (1) according to any of claims 1 to 3, characterised in that the lifting eyelet (5) is provided with a base (6), the base (6) being movable in relation to the body (2) in a cutout (14) in the body (2).

5. Lifting tool (1) according to claim 4, characterised in that via interacting locking means (13, 15) in the body (2) and at the base (6) of the lifting eyelet, the lifting eyelet (5) can be locked in relation to the body (2).

6. Lifting tool (1) according to claim 5, characterised in that the interacting locking means (13, 15) for locking the eyelet (5) are activated by lifting in the lifting eyelet (5).

7. Lifting tool (1) according to any preceding claim, characterised in that the means (7) for fastening the composite item include a threaded rod (7) arranged in each of the first and second arms (3, 4), respectively, the threaded rod (7) extending through at least part of respective arms (3, 4).

8. Lifting tool (1) according to any preceding claim, characterised in that the lifting tool (1) includes one or more indicators (8) for indicating that one or more of the means (7) for fastening to the composite item are correctly fastened to the composite item.

9. Lifting tool (1) according to any preceding claim, characterised in that the lifting tool (1) includes means arranged in the body (2) for maintaining a minimum spacing between the first arm and the second arm (3, 4).

10. Lifting tool (1) according to any preceding claim, characterised in that the lifting tool (1) further includes one or more arms (3, 4) in connection with the body (2), where each additional arm (3, 4) is displaceable for adapting to a specific composite item, and where each additional arm (3, 4) includes means (7) for fastening to the composite item.