AU736367B2

AU736367B2 - Load indicators on traction elements

Info

Publication number: AU736367B2
Application number: AU77637/98A
Authority: AU
Inventors: Hans-Werner Kamper
Original assignee: Spanset Inter AG
Current assignee: Spanset Inter AG
Priority date: 1997-06-03
Filing date: 1998-05-07
Publication date: 2001-07-26
Anticipated expiration: 2018-05-07
Also published as: AU7763798A; WO1998055341A1; JP2002510265A; TW419584B; ES2167901T3; CN1248942A; JP3844512B2; DE59802245D1; EP0984873B1; EP0984873A1; CN1101929C

Description

WO 98/55341 PCT/EP98/02747 TRANSLATION OF AMENDED PAGES

DESCRIPTION

LOAD INDICATORS ON TRACTION ELEMENTS The invention relates to load indicators for indicating tensile stresses on traction elements, for example lashing belts or lashing cables. For the sake of simplicity, these traction elements are referred to hereinafter as "belts" or "belt." They are provided with a loop or eyelet for securing an adaptation part that introduces a counter-holding force to the traction element.

The adaptation part can be, for example, the stud of a shackle or the stop pin of a bracing ratchet.

In lashing or bracing elements, a load indicator of this type serves to indicate visually to the user which load is present, and particularly whether a hazardous situation must be remedied. During the transport of lashed loads, for example on trucks, the load shifts from time to time due to external forces. This shifting often causes severe stress to the lashing element, which can pose a threat to the operator when the load is removed.

Conventionally, load indicators are mounted with ratchet spanners; these indicators preferably serve to indicate the prestress force during lashing, but can also give a warning 1 AMENDED PAGE

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laindication of a stress of the lashing that has occurred due to load shifting. Because of their complicated design, these load indicators are relatively costly.

GB 2 255 109 A discloses a load indicator that has the features of the preamble to claim 1. In this device, which is specified for cables, the indicator body is formed by a cable eye stiffener that has been modified for this purpose. In a simple version of this load indicator, the "cable eye stiffener, which is closed all the way around, is oooo provided in the region of its ring shape that faces the tip o S"of the teardrop shape of the loop, and is no longer acted upon by the inside flanks of the loop, with a radial slit that allows the stiffener legs that rest against the inside •meg e e flanks of the loop some play in the direction toward one another. This small amount of play gives the legs of the stiffener, which is relatively rigid due to its houseshaped cross section, an elastic mobility in the direction toward one another in a high-stress region. A mechanical indicator makes the magnitude of this movement recognizable, and consequently permits conclusions about the load status. This load indicator is only suited for indicating high-load statuses. It is relatively imprecise and, furthermore, fairly structurally complex.

P:\OPER\DW7637-98 rsl.doc-30/05/01 -I b- A load indicator known from GB 2 223 102 A, which only functions similarly to the aforementioned indicator, has a specially-shaped molded body that surrounds the traction pin over 3600 between the loop of the traction element and the stud of the shackle that extends in into the loop, the molded body being deformable under a load. The degree of deformation that occurs under a load is used in the manner of an expansion-measuring device as an indicator for the present load.

i In accordance with the present invention, there are provided 10 load indicators serving to indicate tensile stresses on traction e elements, having a loop or eyelet whose cross-section shape approximates a teardrop outline, and which is provided for initiating a counter-holding force, 1. 15 in which the load is indicated inside the loop or eyelet on :the traction-element side facing away from the region of the :g initiation of the counter-holding force and facing the tip of the teardrop, in which, for this purpose, the load indicator rests against eooee 20 the oppositely-located inside flanks of the loop or eyelet, which converge in the direction of the teardrop tip, the indicator including'an indicator body that can be elastically compressed approximately transversely to the inside flanks; and in which the distance between-the contact regions of the load indicator indicates loads by decreasing with increasing tensile stress and increasing with decreasing tensile stress, characterised in that the indicator body permanently and elastically imposes a force on the inside flanks of the loop or eyelet such that it spreads the loop or eyelet slightly when the traction element is under zero stress.

The above construction is based on the deformation that only the loop or eyelet, which has widened slightly under zero load, experiences under a load due to the increasing approximation of 334? 37't1he teardrop cross-section shape, and its expansion. These belt Fri- P:\OPER\DH\77637-98 rsl doc-30/05/0t Icloops or belt eyelets have an approximately teardrop-shaped outline, with the tip of the drop pointing in the belt direction under a load, when the adaptation part extending into the belt eyelet introduces the counterforce. Usually belt eyelets or belt loops are **e e •go• o ooo ooo P:\OPER\DH\77637-98 rsl doc-29/05/01 -2formed in that the belt generally representing the term "traction element" is shifted at one end by 1800 and, in this relocated position, the belt end is fixed directly on the belt, or, in the case of a cable as the traction element, is spliced with the cable. As the tensile stress increases, the teardrop shape becomes more distinctly formed, because the inside flanks of the belt loop or belt eyelet approach one another. The oo• eg oooe •ego go• P \OPER\DH\77637-98 rsl.doc-30/05/01 -3degree of this approach is visually more easily recognisable due to the load indicator than in the case of mere inspection of the belt loop or belt eyelet.

The invention is described in detail by way of embodiments.

Shown are in: Figs. 1-5 different embodiments of load indicators or indicator bodies in a respective insertion position at a belt loop or belt eyelet, in the left column entitled A, which represents the non-load, inoperative state, and in the 0 right column WO 98/55341 PCT/EP98/02747 entitled B, which represents the dangerous-load state, respectively; Fig. 6 a longitudinal section, extending in the belt direction, through a belt connection analogous to Fig. 3; Fig. 7 a plan view in the arrow direction VII of the ensemble according to Fig. 6; Fig. 8 a modified embodiment of the load indicator in the no-load, inoperative state; Fig. 9 the embodiment according to Fig. 8, in the dangerous-load state; Fig. 10 an indicator body; Fig. 11 a different indicator body; Fig. 12 a view in perspective of the indicator body according to Fig. 11; Fig. 13 a view in perspective of the indicator body according to Fig. 10 fithan insefted -adt a-ti-n part; Fig. 14 a modified indicator body, similar to those according to Figs. 10 through 13; Fig. 15 a side view of the indicator body according to Fig. 14, under different loads, namely T\ a no-load, inoperative state,

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WO 98/55341 PCT/EP98/02747 b 1/3 intermediate load; c 2/3 intermediate load, d dangerous load.

Fig. 16 a secured ratchet spanner as the carrier of the adaptation part; and Figs. 17 18 a secured shackle as the carrier of the adaptation part.

The load indicator 1 serves to indicate tensile stresses on traction elements, which are referred to hereinafter as "belt" 2 for short, but generally represent different types of traction elements such as lashing belts or lashing cables, sling bands and the like. The belt 2 is provided at one end with a loop or eyelet 3 for securing or suspending an adaptation part 4, which is typically formed by a pin 5 that preferably has a circular cross-section shape and extends through the belt eyelet 3 to fix its position. Instead of a pin5,--a 16wor a pih-lke connecting part having a cross-section shape other than a circle can be used.

The load indicator or indicator body 1 is disposed next to the pin 5 in the belt eyelet 3. The arrangement is situated on the side of the tip of the teardrop-shaped belt /4 4eyelet 3, so the load indicator 1 is not directly impacted WO 98/55341 PCT/EP98/02747 by the tensile load. The pin 5, in contrast, rests against the belt eyelet in the wrap corresponding to the rounding of the teardrop shape. This is also the case for an adjacent positioning of the indicator body 1 and the pin corresponding to Figs. 1 and 2. In the case of Fig. i, the indicator body is a one-piece molded part comprising a resilient material in the embodiment as a ring segment having a C-shaped cross section, with a C-shaped opening that faces the side of the traction element, that is, the tip of the teardrop shape. In the case of Fig. 2, the indicator body comprises several parts. Here, it includes two end pieces 16, 17, which rest against the inside flanks 6, 7 of the belt eyelet 3, with an interposed compression spring 18 as an elastically-compressible medium.

The preferred embodiment of the indicator body 1 as a one-piece annular segment that has a C shape in the no-load position has legs or leg ends I1, which pro~ject tawdrd-the side of the traction element, at its ends that limit the C opening. In the embodiment according to Figs. 8 through 14, the leg ends 11 are bent or angled in spreading directions 9, 10 that are oriented away from one another.

Because of the spreading effect they exert under a zero oI\ 9 ad, the leg ends press against the inside of the belt WO 98/55341 PCT/EP98/02747 eyelet, thereby acting on the inside flanks 6, 7 of the loop or eyelet 3.

Because of the compact design, the combination of a pin 5 as the fixing element 4 with the one-piece indicator body 1 in.a cooperative arrangement, as shown in Figs. 4 through 9 and 13, is especially advantageous. In this case, the pin 5 is inserted in the manner of a shaft into the ring-segment-like indicator body 1 having a C shape in the no-load state, and acts upon the concave side of the indicator body 1 under tensile stress. Consequently, the belt eyelet 3 can have a conventional size without impeding the recognizability of the indication.

The cross section of the indicator body 1 also approximates the Greek capital letter Q. It is bent from a metallic spring-steel sheet, but can also be produced from plastic in an injection-molding process. The indicator body is simple to manufacture-because of the-approximatelyrectangular cross section of its ring-curve head 12 and its legs. The cross-section shape can, however, also be hollowed out in the manner of a cable eye stiffener, and then be in a form fit with the belt eyelet 3.

The indicator body according to Fig. 14 has at its %O er leg end 11 viewing tabs 19, which project in the WO 98/55341 PCT/EP98/02747 direction of the upper leg, and extend so as to overlap the end of the upper leg in the no-load position (Fig. The viewing tabs 19 are simply angled parts of the indicator body 1. The tabs are graduated in the manner of a staircase at their side edges, which are clearly visible from the outside in the inserted position. The individual steps of this staircase 20 constitute the load indicator.

The overlapping of, each step with the upper leg end 11 of the indicator body 1 indicates a different load. The threat posed by the different load steps can also be signaled by different colors.

The cross-section thickness of the pin 5 for securing or suspending the belt 2 equipped with the indicator body 1 is smaller than the inside diameter of the head 12 of the indicator body i, the head resembling a curved-ring segment, so, in the case of an overload that enters the dangerous range, a diameter contraction -thepec-tt-thepin 5 is possible, in which the leg ends 11 are compelled to approach one another, that is, come into contact with one another (Figs. 9, 15). This very contact indicates a dangerous situation. The compression of the effective diameter of the ring-curve head can be adapted to certain rm agnitudes of stress through corresponding dimensioning of -9the spring clip. In this way, the distance measure 8 is a readily-recognizable visual indicator for the load state of the belt 2 or the loop 3, that is, for the possible existence of a dangerous situation.

If the load indicator has not yet been loaded, the legs assume a spread position (Fig. in which their leg ends 11 rest against the belt eyelet 3 from the inside, and spread it slightly. Under a load, the belt eyelet 3-.

presses in the radial direction against the head 12 of the oooo 0 ring curve. In the process, the indicator body 1 embodied "as a clip is supported against the pin 5, and stresses the head 12 of the ring curve, thereby bending it. The clip 1 :reacts to the stress like a surface-stressed spiral spring.

The deformation of the head 12 of the ring curve changes 15 the position of the leg ends 11, which approach one another and, under a dangerous load, can even touch one another.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that that prior art forms part of the common general knowledge in-Australia.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

i rn /7 Q fC) WO 98/55341 PCT/EP98/02747 LIST OF REFERENCE CHARACTERS 1 Indicator body 2 Belt 3 Belt eyelet 4 Adaptation part Pin 6 Inside flank 7. Inside flank 8 Distance measure 9 Spreading direction Spreading direction 11 Leg end 12 Ring-curve head 13 Belt-eyelet length 14 Center longitudinal axis Length 6-End-piece 17 End piece 18 Compression spring 19 Viewing tab Staircase

Claims

1. Load serving to indicate tensile stresses on traction elements, having a loop or eyelet whose cross-section shape approximates a teardrop outline, and which is provided for initiating a counter-holding force, in which the load is indicated inside the loop or eyelet on the traction-element side facing away from the region of the initiation of the counter-holding force an facing the tip of the teardrop, in which, for this purpose, the load indicator rests against se "the oppositely-located inside flanks of the loop or eyelet, "which converge in the direction of the teardrop tip, the indicator including an indicator body that can be elastically 1: 5 compressed approximately transversely to the inside flanks; ee r and in which the distance between the contact regions of the load indicator indicates loads by decreasing with increasing tensile stress and increasing with decreasing tensile stress, S 20 characterised in that the indicator body permanently and elastically imposes a force on the inside flanks of the loop or eyelet such that it spreads the loop or eyelet slightly when the traction element is under zero stress. 4?7 P:\OPER\DH\77637-98 rsl.doc29/05/01 lla-

2. The load indicator according to claim 1, characterized in that the indicator body is a one-piece molded part comprising a resilient material, and rests with its ends, which are oriented approximately in the direction of the traction-element extension toward the tip of the teardrop, against the inside flanks of the loop or eyelet such that the eyelet is widened slightly when the traction element is under zero stress. e 12

3. The load indicator according to claim 1 or 2, characterized in that the indicator body is shaped S approximately like a ring segment or a C with an opening :eO that faces the securing point of the traction element. g. 4. The load indicator according to claim 3, characterized in that the ends of the indicator body (1) that limit the ring-segment opening or the C opening have legs or leg ends (11) that project toward the side of the traction element. The load indicator according to one or more of the foregoing claims, characterized.in that the leg ends 0 C7 T C, wo 98/55341 PCT/EP98/02747 (11) are bent or angled in spreading directions that are oriented away from one another.

6. The load indicator according to claim 4 or characterized by at least one viewing tab (19) that is disposed at a leg or leg end (11) and projects in the direction of the other leg, and, in the no-load position, extends so as to overlap the other leg.

7. The characterized a graduation.

8. The characterized tab (19) as a load indicator according to claim 6, in that the viewing tab (19) is provided with load indicator according to claim 6 or 7, by at least one stepped edge of the viewing load indicator. -9 -Theload indicator according to one or more of the foregoing claims, characterized in that the pin of an adaptation part that introduces the counter-holding force to the traction element lies in a ring-segment-like or C-shaped indicator body P:\OPER\DH\77637-98 rsl.doc-30/05/01 -14- The load indicator according to one or more of the foregoing claims, characterized in that the one-piece indicator body has approximately the shape of the Greek capital letter 0.

11. The load indicator according to one or more of the foregoing claims, characterised in that the indicator body is bent from a metallic spring-steel sheet, or is produced from plastic in an injection-molding process. e

12. The load indicator according to one or more of the e foregoing claims, characterised by an approximately-rectangular 10 cross-section shape of its ring-curve head and/or its legs and/or leg ends.

13. The load indicator according to one or more of the foregoing claims, characterised in: ~that the load indicator is secured to a traction element; and 15 that an adaptation part with a pin-like stopping part for securing or suspending the traction element is provided in such a manner that the cross section thickness or outside diameter of the adaptation part is smaller than the inside diameter of the head of the indicator body, the head being shaped like a ring-curve segment or a C.

14. The load indicator according to claim 13, characterised in that the adaptation part is a ratchet or a shackle. A traction element having a belt eyelet and a load indicator that rests against its inside flanks in the manner of a cable eye stiffener, according to one or more of the foregoing claims, wherein the belt-eyelet length, measured in the load direction of the traction element, is greater than the length of the indicator body, measured in the direction of the center 3 0 longitudinal axis. ,C c 0_Y P:\OPER\DH\77637-98 rs Idoc-29/05/01

16. A traction element according to claim 15, characterised in that the length of the indicator body is between 50 and percent of the non-loaded belt-eyelet length.

17. A load indicator, substantially described with reference to the drawings. as hereinbefore S0 *to .09 see* S S .410 5 *c **f S S *@5S

18. A traction element, substantially as hereinbefore described with reference to the drawings. DATED this 30th day of May, 2001 SPANSET INTER AG By DAVIES COLLISON CAVE Patent Attorneys for the applicant '-r7 C c/D