SE538548C2

SE538548C2 - Fastening device and use of such a device

Info

Publication number: SE538548C2
Application number: SE1451408A
Authority: SE
Inventors: Wennersten Elias; Harpa Alexander
Original assignee: Combolt Ab
Priority date: 2014-11-21
Filing date: 2014-11-21
Publication date: 2016-09-13
Also published as: WO2016080888A1; SE1451408A1

Abstract

ABSTRACT A fastening device which in one embodiment comprises at least two connecting parts, onestem part (1) and one locking part (2) arranged to engage with each other by connectingthe locking part (2) onto the stem part (1) along a main longitudinal direction of the stempart (1) from a distal end towards a proximate end along a main axis, wherein the firstpart, being one of said at least two parts is in circumferential direction provided with atleast one axial segment with slightly curved flanges (4) and at least one axial segment withsubstantially flat surface (5), and the second part, being the other of said at least two parts(1,2), in circumferential direction being provided with at least one axial segment withprojections (11) and at least one axial segment with substantially flat surface (12), and atleast one of said two connecting parts (1,2) is rotatable in relation to the other to bringthe slightly curved flange (4) and the projection (5) in and out of engagement with each other.

Description

Fastening device and use of such a deviceThe present invention refers to a fastening device comprising at least two parts, andparticular to a bolt and a nut arranged to be engaged with each other, in a rapid way by engaging flanges with projections.

Background Traditional fastening devices comprise a screw or a bolt with external threads and a nutwith internal threads, where the nut is threaded on to the bolt and screwed upwards untila desired attachment is achieved. A screw is mostly used to secure or fasten things or toattach an object to for example a wall, where the screw is attached directly into thematerial/article. A bolt and a nut is most often used to fasten a stack of parts together,where the bolt is brought through a hole in the article and the nut is thereafter threadedonto the body of the bolt to secure the article between the bolt head and the nut. Thebolt and the nut are kept together by a combination of their threads friction, a slight stretch of the bolt and compression ofthe parts.

The traditionally used screws as well as bolts and nuts have a number of potential prob-lems. For example, if the bolt is long it takes a long time to thread the nut from the bot-tom of the bolt towards the head of the bolt to fasten the article. lt can also be hard tothread the nut onto the bolt if the space where the bolt and nut is to be used is limited.Furthermore, the nut has a tendency to unthread when it is exposed to stress or vibra- tions or the bolt can break. Temperature differences can possibly also affect the thread- ing.

One of the major problems with traditionally used fastening means is that both the screwas well as the bolt and nut are subjected to loosening over time. Vibration, stress anddilation will also cause the fastening device to loosen over time. This problem has previ-ously been solved for example by using various locking mechanisms. For example one could use adhesives, safety pins or lockwire, nylon inserts or slightly oval-shaped threads. lt is also possible to achieve a better locking if one would use two nuts threaded onto thebolt after each other. The bottom nut would then prevent unthreading of the top nut fromthe bolt. Longer periods of vibration or stress would however unthread the nuts anyway or the lower nut would break from stress.

The problem that it takes a long time to thread a nut onto a long bolt has for examplebeen addressed by WO2014/088600. WO2014/088600 describes a rapid-engaging,positive locking machine screw mechanism comprising a screw, wherein the body of thescrew comprises male threads and at least one longitudinal segment devoid of threads.The application further describes a work piece which defines a hole having female threadsfor receiving the screw and at least one longitudinal segment devoid of threads. Thelongitudinal screw segment devoid of male threads and the longitudinal hole segmentdevoid of female threads are arranged such that the screw body is longitudinally receivedin the hole without engagement of the male screw threads with the female work piecethreads. The male and female threads engage upon rotation of the screw with respect tothe mating threaded work piece. The screw and the work piece are also provided with alocking feature and a mating locking feature, respectively. The locking feature comprises aboss and the mating locking feature comprises a recess to receive the boss. The lockingfeatures limit the rotation of the threaded sections to a maximum of one-half of a rota- tion.

Problems still arising with the screw mechanism according to WO2014/088600 is that ithas threads and it requires a boss and a recess to receive the boss. Threads are subjectedto loosening over time, which WO2014/088600 has solved by using a boss and a recess.

The use ofthe boss and recess is more complicated to manufacture.

The present invention solves these and other problems.

Hence, one aspect of the present invention is a fastening device which in one embodiment comprises at least two connecting parts, one stem part and one locking part arranged to engage with each other by connecting the locking part onto the stem part along a main longitudinal direction of the stem part from a distal end towards a proximate end along amain axis, wherein the first part, being one of said at least two parts is in circumferentialdirection provided with at least one axial segment with slightly curved flanges and at leastone axial segment with substantially flat surface, and the second part, being the other ofsaid at least two parts, in circumferential direction being provided with at least one axialsegment with projections and at least one axial segment with substantially flat surface,and at least one of said two connecting parts is rotatable in relation to the other to bring the slightly curved flange and the projection in and out of engagement with each other. ln another aspect of the invention, the fastening device further comprises a resilient thirdpart arranged to apply a spring force against the stem part along said main axis towardsthe distal end. The third part can either be attached to the stem part or the locking part or be a separate part. ln a further aspect of the invention, the fastening device comprises a first part being thestem part and the second part being the locking device, wherein the projections areprovided on the locking part and a distance from the upper end of the locking part to theprojections is different from the distance from the second end of the locking part to the projections.

Described are also the use of a fastening device for assembling of pipe ends and for rapid engaging and locking of a bottle cap to a bottle or a jar. ln the following, the invention will be described in detail, with reference to exemplifying embodiments of the invention and to the enclosed drawings, in which: Fig. 1 shows a perspective view of the fastening deviceFig. 2A shows a perspective side view of the stem partFig. 2B shows perspective front view of the stem partFig. 3 shows a perspective view of the flanges Fig. 4 shows a magnified view of a part of the flanges Fig. 5A shows a perspective view of the locking part as a hexagonal nutFig. 5B shows a perspective view of the locking part as a wing nut.

Fig. 6 shows a cross-sectional view of the locking part For the purpose ofthis description and claims the main axis is defined as the vertical axisgoing through the center ofthe stem part as oriented in Fig. 1. The terms ”upwards”, H ll ”downwa rds , vertica |H and any derivatives thereof re|ates to the invention as oriented inFig. 1. Furthermore, a bolt is defined to be a fastening means comprising a long pin and ahead, wherein the pin is connected to a nut, used to fasten things together. Further a flatsurface is defined to be a radially curved surface without any projections or flanges. The flanges are curved radially along the axial direction ofthe stem part or locking part.

Referring to Fig. 1-6 a fastening device in accordance with the present invention suitablycomprises at least two connecting parts, a stem part 1 and a locking part 2, arranged toconnect and engage with each other into a locked state in which said stem part 1 andlocking part 2 together form said fastening device for the purpose of securing an article (not shown) between the stem part and the locking part.

One ofthe said at least two connecting parts is provided with at least one axial segmentwith slightly curved flanges 4 and at least one axial segment with substantially flat surfaces5, and the other of said at least two connecting parts is, in circumferential direction,provided with at least one axial segment with projections 11 and at least one axial seg-ment with substantially flat surface 12, and at least one of said two connecting parts isrotatable in relation to the other to bring the slightly curved flange and the projection in and out of engagement with each other.

Fig. 1 shows a fastening device comprising a stem part 1, in the shape of a bolt and alocking part 2, in the shape of a nut, wherein the bolt comprises flanges 4 and at least oneaxial segment with substantially flat surface 5. The locking part 2 comprises projections 11and at least one axial segment with substantially flat surface 12. The flanges 4 on the stempart 1 are arranged to engage and connect to the projections on the locking part 2. Fig. 1 further shows a resilient third part 3 arranged between the proximate end of the stem part 1 and the locking part 2. The resilient third part 3 is defined by having a hole thereinto allow the third part 3 to be connected onto the stem part 1 from the distal end towardsthe proximate end. The flanges 4 on the stem part 1 form a locking feature together withthe projections (11) on the locking part, by connecting the stem part 1 and the locking part2 and rotating at least one of the two connecting parts so that the projections 11 and theflanges 4 engage with each other. lt is to be noted that the flanges 4 can also be arrangedon the stem part 1 and the projections 11 will in that case be arranged on the locking part 2. ln order to attach the locking part 2 to the stem part 1 the locking part 2 has to be posi-tioned so that the at least one substantially flat surface 12 align with the at least one axialsegment comprising flanges on the stem part 1. Upon aligning of the substantially flatsurface 12 with the segment comprising flanges 4, the locking part 2 can be connected toand translated along the main axis from a distal end towards a proximate end of the stempart 1, until a desired position is achieved. To engage the stem part 1 and the locking part2, at least one of the said connecting parts is rotated a quarter of a rotation of an axis sothat the flanges 4 on the stem part 1 align with the projections 11 on the locking part 2.The projections 11 will be lead upwards, towards the proximate end of the stem part 1,and over one of the upwards projecting edges 6 on the flanges 4 to a countersunk section 7.

An advantage of the use of the fastening device according to the invention is a rapid and tight locking mechanism without the need to follow-up draft ofthe locking part.

To separate the locking part 2 from the stem part 1, the second part 2 must again berotated so that the at least one axial segment of projections 11 align with the at least one axial segment of substantially flat surface 5 on the stem part 1.

The resilient part 3 is provided with a hole to connect the resilient part 3 to the stem part1. The resilient part can be added from the bottom of the body of the stem part 1 and upwards towards the head of the stem part 1. The function of the stem part 1 is to give a resilient function which will give a tighter fit between the locking part and the article to befastened through which the locking part is added. When the projections 11 on the lockingpart 2 are to be engaged with the flanges 4 on the stem part 1, the resilient part 3 will make it easier to push the projections 11 over the top of the flanges 4.

The resilient third part is arranged to apply a spring force against the stem part along saidmain axis towards the distal end and against and/or to apply a spring force against the locking part along said main axis.

The resilient third part 3 can either be a separate part or attached to the stem part 1 orattached to the locking part 2. The resilient third part can for example be a rubber pack-ing, an elastic washer or the like. lt could also be for example a cylinder head gasket for anengine. The resilient third part 3 is exchangeable/replaceable so that the stiffness can be adapted to the specific use.

Fig. 2A shows the stem part 1 of the locking device in a side view and Fig. 2B shows thestem part 1 of the locking device in a side view. ln Fig. 2B the resilient part 3 is also shown.The stem part comprises a head and a body extending from the head. The body of thestem part 1 is provided with at least one axial segment with flanges 4 and at least oneaxial segment of substantially flat surface 5. The flanges 4 are designed to achieve a tightand locked engagement with projections 11 on the locking part 2 (not shown in Fig. 2).

The flanges will be described more in detail with reference to Figs. 3 and 4.

The stem part 1 is preferably provided with at least two axial segments with flanges 4 andat least two axial segments of substantially flat surfaces 5. lt will however be understoodby a person skilled in the art that it could be provided with less or more segments withflanges and substantially flat surfaces, respectively. The number of axial segments withflanges and substantially flat surfaces, respectively, can be adapted to the size of the stem part or to the intended use of the fastening means. ln this application the stem part 1 is shown as a hexagon-headed bolt with flanges on onlya lower part of the length of the stem part body. lt is also possible to have flanges alongthe entire length of the screw body. lt could however also be any other type of bolt, screw or fastening means provided with flanges 4.

The stem part 1 can further be integrated in for example a sheet metal, a pipe, a plastic cap or any other type of material suitable for integration with a bolt or screw.

Fig. 3 shows an axial segment of flanges 4. The flanges 4 comprise two upwards projectingedges 6 at either end of a countersunk section 7. The flanges can be arranged either on the stem part 1 or the locking part 2.

The vertical distance between the lower end of one flange and the upwards projectingedges 6 on the next underlying flange is at least of the same height as that of one projec-tion, to assure that the projection 11 can be brought into the countersunk section 7 of the flange 4.

To accomplish the insertion ofthe stem part 1 into the locking part 2, the width of an axialsegment of flanges 4 is somewhat narrower than the width of an axial segment withsubstantially flat surface. This will assure that it possible to move the locking part 2 up-wards and downwards on the stem part 1 rapidly without engaging the flanges and projections.

As mentioned above, the flanges could be provided either on the stem part or the locking part, depending on the intended use of the fastening device.

Fig. 4 shows a magnified view of a part of a flange 4 showing one upwards projecting edge6 and a part of the countersunk section 7. The upwards projecting edge 4 comprises asloping outer wall 8, a top 9 and an inner wall 10. The lower part 8A of the sloping outerwall 8 is in principal perpendicular to the bottom part of the flange and changes into a sloping part 8B. The top of the upwards projecting edges is preferably rounded, but could also have other shapes. The top continues into an inner wall, where the upper part 10A ofthe inner wall is a sloping wall and the lower part 10B of the inner wall is either a slopingwall or perpendicular to the countersunk section 7. The sloping of the outer wall is neces-sary to make the projections 11 slide up against the upwards projecting edges and overthe top 9 into the countersunk section 7. At least one of the two inner walls 10B of eachflange 4 has an angle towards the bottom of the countersunk section 7 that is essentially90 degrees, in order to assure a locked state where the projections 11 stay in an engaged mode with the flanges. The angle could however differ between 85-95 degrees.

Each flange is provided with an upwards projecting edge in each end. And the projectingedges can be made different in the two ends. As well as the inner and outer walls of the flanges can be different. lf needed a tool can be used to connect the locking part to the stem part. This can beuseful if the locking is very tight and it is hard to rotate the locking part or stem part byhand. Any tool that can be used to hold and rotate either the stem part or the locking part, or both, can be used for this purpose.

Fig. 5A shows a perspective view of a locking part 2, shown as a hexagonal nut. The lockingpart 2 is provided with at least one axial segment with projections 11 and at least one axialsegment of substantially flat surface 12. The projections are designed to achieve a tight and locked engagement with the flanges 4 on the stem part 1 (not shown in Fig. 5).

The width of an axial segment of projections 11 is somewhat narrower than the width ofan axial segment with substantially flat surface 5 on the stem part 1 in order to make it possible to move the locking part 2 upwards and downwards on the stem part 1.

The locking part is preferably provided with at least two axial segments with projections11 and at least two axial segments of substantially flat surface s 12, but could however beprovided with less or more segments with projections 11 and substantially flat surfaces 12, respectively. ln this application the locking part 2 is shown in the shape of a hexagonal nut. lt couldhowever also be a wing nut (as shown in Fig. 5B), a captive nut, a threaded sleeve or anyother type of nut/sleeve which has the ability to engage with the stem part 1. The lockingpart 2 could also be a general piece of structure into which the stem part 1 is to be re-ceived, provided that the locking part can be provided with the projections 11. The lockingpart 2 could for example be integrated in a cap, a pipe or any other application. Thefunction of the locking part can be migrated into a welded nut or in any other parts in a manufacturing line.

The width of the projections 11 is adapted to fit within the flanges 4 and can hence not be wider than the width of the countersunk section 7 on the flanges 4.

The locking part can further comprise a marking 13 to show the placement of projections11 or the axial segments of substantially flat surface 12 to facilitate correct placement ofthe locking part 2 in relation to the flanges 4 on the stem part 1 during connection of the locking part 2 and stem part 1 to each other.

Fig. 6 shows a cross-sectional view of the locking part 2. ln this embodiment of the appli-cation, the distance L1 from the top of the locking part (as shown in Fig. 6) to the top ofthe first projection differs from the distance L2 from the bottom of the nut to the bottomof the last projection. The distance L1 is preferably twice the corresponding distance onL2. This feature makes it possible to turn the locking part upside down if the fasteningdevice is not locked tight enough against the article and will then have a tighter fit when itengages with the stem part 1. ln the same way is it possible to have a looser fit if thefastening device is turns out to be locked to tight against the article, or if it is not possible to rotate the stem part or locking part into engagement with each other.

Above, an exemplifying preferred embodiment has been described. However, it is realized that the invention can be varied without departing from the basic idea of the invention.

The invention as it has been described can for example be used on skateboards. Fasteningmeans on skateboards are exposed to a lot of vibrations and it is hard to find fasteningmeans where no retightening is needed. A lost fastening means during use of a skate-board could mean that the person using the skateboard is hurt. The fastening meansdescribed in this application will make sure that the wheels are securely fastened to the skateboard.

The invention can further be used in different types of stairs, for example fire escapes andindustrial stairs where a lot of movement occurs and the vibrations and stress affects thefastening means. The fastening means according to the invention will be advantageoussince there is no need for retightening the locking part. The fastening means according tothe invention will also save time during installation, because of the rapid locking due to the use of axial segments without flanges 4 and projections 11, respectively.

Another advantageous use is in ladder scaffolding, where the scaffolding is to be mountedand dismantled over and over again. lt will not only be more time efficient compared toregular fastening devices. lt will also be safer and have greater structural strength sincethe flanges will stay inside the protrusions until a tool or a person actively rotates at least one of the connecting parts.

Furthermore the invention as it has been described can be used in applications wherethere is little space for mounting, in motor vehicles, lawn mowers, furniture productionetc. The screws/bolts are often located in areas that are difficult or not possible to accessfor follow-up draft/retightening. The axial segment with substantially flat surface willmake it easier to mount the fastening device in areas with limited space as compared to aregular bolt and nut where one would need to rotate the nut and/or bolt upwards until alocked state is achieved. The easier mounting is due to the fact that the locking part canbe pushed upwards along the stem part's main axis until a desired locking is accomplishedand then one of the two connecting parts is rotated into a locked state where the projec-tions fit within the countersunk part of the flanges. The locking mechanism provided with the present invention do not need any follow-up draft or retightening. 11 ln another application of the present invention, the fastening device according to theinvention is utilized for rapid engaging and locking of a bottle cap to a bottle. The neck of abottle is provided with at least one axial segment of flanges 4 and at least one axialsegment of substantially flat surface for rapid engagement and fast locking as has beendescribed above. The bottle cap is provided with at least one axial segment of projectionsand at least one axial segment of substantially flat surface. At least one of said two parts 1,2 is rotatable in relation to the other to bring the slightly curved flanges 4 and the projec- tions 11 in and out of engagement with each other. lt is to be noted that the flanges could also be provided on the locking part and in that case the projections will be provided on the stem part.

The embodiment described above can also be applied to for example medicine jars or bottles or other types ofjars and bottles with screw cap.

The use of the fastening device according to the invention incorporated into a medicinejar or bottle gives the advantage that it is easier to open for a person with reduced manualpower or for persons experiencing problems with un-screwing and screwing caps ontobottles, jars and bottles. lt could for example make it easier for elderly persons or persons with rheumatism to open bottles, jars and cans without the need of help from others. ln another application of the present invention, the fastening device is utilized for assem-bling pipe ends, wherein the stem part 1 is arranged in or on one pipe and the lockingpart 2 is arranged in a second pipe, wherein at least one of said two parts is rotatable inrelation to the other to bring the axial segment of slightly curved flanges 4 and the axialsegment of projections 11 in and out of engagement with each other and thereby assem-bling the two pipes together, in the same way as has been described with reference toFigs. 1 and 3. The flanges on the stem part 1 can either be attached inside one of the pipeends or the flanges can be attached to the outside of one of the pipe ends. The pipecontaining the locking part 2 will surround the pipe containing the stem part when they are brought into engagement with each other. 12 Hence, the invention is not to be considered limited to the above described embodiments, but may be varied within the scope of the enclosed claims.

Claims

1. Fastening device comprising at least two connecting parts, one stem part (1) and onelocking part (2) arranged to engage with each other by connecting the locking part (2) ontothe stem part (1) along a main longitudinal direction of the stem part (1) from a distal endtowards a proximate end, wherein the first of the at least two connecting parts, being either the stem part (1) or the locking part(2) is in circumferential direction provided with at least one axial segment with slightly curvedflanges (4) and at least one axial segment with substantially flat surface (5), and the second of the at least two connecting parts, being the other of said at least two parts(1, 2), in circumferential direction being provided with at least one axial segment withprojections (11) and at least one axial segment with substantially flat surface (12), and at least one of said two parts (1, 2) is rotatable in relation to the other to bring the slightlycurved flange (4) and the projection (11) in and out of engagement with each other,characterized in that the axial segment with flanges (4) is provided with upwards project-ing edges (6), one in each end ofthe flange (4), and a countersunk section (7) between the edges (6) for receiving the projection (11) ofthe other of said two parts (1, 2).

2. Fastening device according to claim 1, characterized in that the edges (6) comprise asloping outer wall (8) and an inner wall (10) with a lower part (10B) essentially in an axial direction ofthe stem part (1).

3. Fastening device according to claim 1 or 2, wherein the angle defined between the lower part of inner wall (10B) ofthe edges (6) and the countersunk section (7) is 85-95°.

4. Fastening device according to any of the preceding claims, characterized in that at least twoaxial segments of flanges (4) are provided on said first of the at least two connecting parts (1,2) and at least two segments of projections (11) on the other of said two parts (1,2).

5. Fastening device according to any of the preceding claims, also comprising a resilient (3)third part arranged to apply a spring force against the stem part (1) along said main axis towards the distal end. 14

6. Fastening device according to claim 5, wherein the third part (3) is attached to either the stem part (1) or the locking part (2).

7. Fastening device according to any of the preceding claims, wherein the first part is thestem part (1) and the second part is the locking device (2), characterized in that theprojections (11) are provided on the locking part (2) and a first distance (L1) from theupper end of the locking part (2) to the projections (11) is different from a second distance (L2) from the second end ofthe locking part (2) to the projections (11).

8. Fastening device according to claim 7, wherein the first distance (L1) is twice the corre- sponding second distance (L2).

9. Use of a fastening device according to any of the preceding claims for assembling pipeends, characterized in that the stem part (1) is arranged in or on one pipe and the locking part (2) is arranged in asecond pipe, wherein at least one of said two parts is rotatable in relation to the other tobring the axial segment of slightly curved flanges (4) and the axial segment of projections(11) in and out of engagement with each other and thereby assembling the two pipes together.

10. Use of a fastening device according to any of claims 1-8, for rapid engaging and lockingof a bottle cap to a bottle or a jar, characterized in that the first of the at least two connecting parts, being either the stem part (1) or the lockingpart (2) is formed upon a neck of a bottle or a jar, and the second of the at least two connecting parts, being the other of said at least two parts(1, 2), is provided within a bottle cap orjar cap and at least one of said two parts (1, 2) is rotatable in relation to the other to bring the slightly curved flange (4) and the projection (11) in and out of engagement with each other.