Crimping ring and method for making same

Information

  • Patent Grant
  • 6481061
  • Patent Number
    6,481,061
  • Date Filed
    Thursday, August 23, 2001
    22 years ago
  • Date Issued
    Tuesday, November 19, 2002
    21 years ago
Abstract
A crimping ring comprises a rolled-up piece of metal strip (10). A first connection means formed at the first end (12) comprises a first setback overlap surface (16) together with at least one female member (18) recessed from said first surface. A second connection means formed at the second end (14) comprises a second setback overlap surface (20) together with a male member (22) formed to project from said second surface. On connection, the male member (22) is engaged in the female member (18) and is fixed thereto, while the overlap surfaces (16, 20) are disposed one against the other so as to define a connection zone of thickness that is substantially equal to the thickness of the main portion of the strip.
Description




The present invention relates to a crimping ring comprising a rolled-up piece of metal strip whose two ends include respective first and second connection means that co-operate with each other to interconnect said ends.




A crimping ring is known, e.g. from patent application GB 2 247 041, that is made from a rolled-up piece of metal strip, with the ends of the piece being cut out in such a manner as to present complementary profiles, for example one end having a T-shaped extension while the other end has a cutout of complementary shape. These ends are engaged one in the other and thereafter they need to be fixed together permanently, e.g. by welding.




A crimping ring is sometimes subjected to extremely high stresses, particularly during the crimping operation which is performed in order to obtain the desired degree of clamping around the object to be clamped, e.g. a bellows for a universal joint.




The type of connection mentioned above is poor at withstanding particularly high stresses, specifically when the stress acts in a direction other than the longitudinal direction of the strip. This applies in particular to stresses acting perpendicularly or substantially perpendicularly to the plane of the strip.




Document EP 0 610 108 discloses a crimping ring made from a metal strip whose ends are of a thickness that is close to half the thickness of the strip itself, and whose ends having fixing studs, for example. To connect those ends together, a fixing plate having holes, for example, is used with the plate being positioned so that the studs at the ends of the strip engage in the holes in the plate. Thereafter, the free ends of the studs are riveted to the plate.




That type of connection withstands relatively high stresses in satisfactory manner. However it suffers from the drawback of requiring the use of a piece that is separate from the piece of strip. The plate therefore needs to be machined separately, and stored appropriately in supply stores, and a tool must be provided enabling it to be put into place at the ends of the strip.




Thus the presence of such a plate increases the cost of the crimping ring.




Furthermore, when stresses act in the connection zone, reaction forces bear firstly between a first end of the strip and the plate, and secondly between the second end of the strip and the plate. In other words, these forces do not act to any significant extent between the two ends of the strip themselves. In some cases where stresses are particularly high, this can result in one end being slightly offset relative to the other.




An object of the present invention is to propose a crimping ring that is simple and inexpensive to make, and that is suitable for overcoming the above-mentioned drawbacks.




This object is achieved by the fact that the first connection means comprise a first overlap surface formed in the first end of the piece of strip as a setback from the first face of said piece of strip, together with at least one female member recessed from said first overlap surface, while the second connection means comprises a second overlap surface formed in the second end of the piece of strip as a setback from the second face of said piece of strip, together with a male member projecting from said second overlap surface, and in that the male member is engaged in the female member and fixed thereto while the overlap surfaces are placed one against the other so as to define a connection zone whose thickness is substantially equal to the thickness of the main portion of the piece of strip.




It will be understood that with the invention the two connected-together ends of the strip are in contact with each other via a relatively large area, corresponding to the areas of the overlap surfaces. As a result, the stresses acting in the connection zone apply to an area that is very considerably greater than for the crimping ring of document GB 2 247 041. This leads to much more uniform distribution of the stresses and to much greater strength in the connection zone.




In particular, since the overlap surfaces are placed one against the other, they provide a high level of resistance to stresses acting in a direction other than the longitudinal direction of the strip.




Compared with the crimping ring disclosed in document EP 0 610 108, the ring of the present invention presents the advantage of avoiding the presence of an additional plate. In addition, the connection establishes close and direct contact between the two ends of the strip.




Advantageously, at least one of the first and second overlap surfaces is formed in a setback which has a wedging rim, while the outline of the other one of the overlap surfaces presents a wedging edge co-operating with said rim to oppose forces directed transversely relative to the piece of strip.




The co-operation between the wedging edge and the wedging rim enables the connection to withstand forces acting substantially in the plane of the strip, but in a direction that crosses the longitudinal direction of the strip. This co-operation is additional to the engagement of the male member in the female member and increases the strength of the connection against stresses tending to cause the two ends of the strip to pivot about an axis corresponding to a diameter of the ring.




Advantageously, the female member is formed by a through opening in the piece of strip extending from the first overlap surface.




Thus, the female member(s) can be constituted merely by an opening or a notch formed in the end of the strip, e.g. by punching. The male member can pass through the opening and can be riveted into it.




The invention also provides a method of manufacturing a crimping ring in which first and second connection means are formed respectively at the first and second ends of a piece of metal strip, and in which these ends are connected together by making said first and second connection means co-operate with each other.




The invention seeks to provide a manufacturing method enabling a crimping ring to be made that overcomes the drawbacks of the cited prior art in simple manner.




This object is achieved by the fact that a first setback is formed in the first end of the piece of strip from the first face thereof, the surface of the first setback defining a first overlap surface, at least one female member is recessed from said first overlap surface, a second setback is formed in the second end of the piece of strip from the second face thereof, the surface of this second setback defining a second overlap surface, at least one male member is formed to project from said second overlap surface, the overlap surfaces are placed one against the other, the male member is engaged in the female member, and said male member is fixed to said female member, and in that the first and second setbacks are made in such a manner that the thickness of the ring in the connection zone defined by the overlap surfaces disposed one against the other is substantially equal to the thickness of the main portion of the piece of strip.




The setbacks at the two ends of the strip are made, for example, by localized stamping or embossing. As explained below, these setbacks can be made simultaneously or one after the other. In order to engage the male member in the female member, the two ends of the strip are brought together until they are overlapping. This can be done, for example, after a stage in which the piece of strip is rolled up.




Advantageously, a female member is made as a through hole in the piece of strip, the ends of the strip are connected together so that a male member appears in said female member, and said male member is deformed in order to be fixed to said female member.











The invention will be well understood and its advantages will appear more clearly on reading the following detailed description of embodiments given as non-limiting examples. The description refers to the accompanying drawings, in which:





FIG. 1

is a plan view of a piece of metal strip whose two ends are shaped in such a manner as to present setbacks and the male and female members used for fixing the strip;





FIG. 2

is a section view on line II—II of

FIG. 1

;





FIG. 3

is a fragmentary elevation view of a ring prior to interconnecting the two ends of the piece of strip constituting it;





FIG. 4

is a section on a radial plane of the ring (on line IV—IV of

FIG. 3

) in the zone where the ends of the piece of strip are interconnected;





FIG. 5

is a plan view of the two ends of the piece of strip before they are interconnected, showing a variant embodiment;





FIG. 6

is a section view on line VI—VI of

FIG. 5

;





FIG. 7

is a plan view of the ends of the piece of strip before they are connected together, in another variant embodiment;





FIG. 8

is a section view on line VIII—VIII of

FIG. 7

;





FIG. 9

is a plan view of the two ends of a piece of strip before they are connected together in another variant embodiment;





FIG. 10

is a section view on line X—X of

FIG. 9

;





FIG. 11

is a plan view of the ends of a strip before they are connected together in yet another variant;





FIG. 12

is a section view on line XII—XII of

FIG. 11

;





FIG. 13

is a longitudinal section view through the ends of a piece of strip in another variant, before they are connected together;





FIG. 14

is a longitudinal section view of the two ends of a piece of strip while they are being connected together in yet another variant;





FIG. 15

is a plan view of one end of a piece of strip in yet another variant;





FIG. 16

is a longitudinal section showing the other end of the piece of strip suitable for co-operating with the end shown in

FIG. 15

;





FIG. 17

is a cross-section showing the connection between the ends of

FIGS. 15 and 16

;





FIG. 18

is a fragmentary plan view of a metal strip during the manufacturing process in an advantageous implementation; and





FIG. 19

is a partially cutaway side view of the strip shown in FIG.


18


.












FIG. 1

shows a piece of metal strip


10


, e.g. of steel or aluminum, of the type suitable for making a crimping ring. By way of example, this strip is cut from a sheet and presents substantially constant thickness over its entire length, except at its ends. The two ends


12


and


14


of the strip have complementary connection means enabling them to be interconnected to close the strip and shape it into a crimping ring, as can be seen in FIG.


3


.




The first connection means formed at the end


12


of the strip comprises a setback with solid portions forming a first overlap surface


16


. Holes


18


are formed through this setback and constitute female connection members.




The end setback


12


is arranged so that the thickness E


12


of said end is substantially equal to half the thickness E of the piece of strip.




The second connection means formed at the second end


14


of the strip likewise has a setback whose surface forms a second overlap surface


20


.




Studs


22


project from this overlap surface, forming projecting male members. In

FIG. 3

it can be seen that the studs


22


are designed to engage in the holes


18


to form a male-female connection.




The setback which includes the surface


16


is made from the first face


10


A of the piece of strip. It is thus this first face which is concave in the region of the setback. In contrast, the setback which includes the second overlap surface


20


is formed from the second face


10


B of the strip. The thickness of this setback zone as measured between the face


10


A and the overlap surface


20


, and referenced E


14


is likewise substantially equal to half the thickness E of the strip. Thus, when the two overlap surfaces are placed one against the other, as shown in

FIG. 4

, the total thickness EZ of the connection zone is substantially equal to the thickness E of the strip.




Each of the overlap surfaces


16


and


20


extends over the entire width L of the strip. At its side remote from the free edge


14


A of the end


14


, the overlap surface


20


presents a rim


20


A which constitutes the transition between the main portion of the strip and the surface


20


.




Similarly, the overlap surface


16


joins the main portion of the strip via a rim


16


A located remotely from the free edge


12


A of the end


12


. The lengths l of the surfaces


16


and


20


are substantially equal (although allowance must be made for taking up slack associated with the ring being curved: the surface that is to be on the inside can be slightly shorter), so that when the two surfaces


16


and


20


are placed one against the other as in

FIG. 3

, the edge


14


A comes to bear against the rim


16


A, while the edge


12


A comes to bear against the rim


20


A.




The edge


14


A and the rim


16


A are complementary in shape. It can be seen that they are not rectilinear, but that they are slightly curved. This produces a wedging effect in the transverse direction extending across the longitudinal direction of the strip when the rim


16


A is co-operating with the edge


14


A. The same applies for co-operation between the edge


12


A and the rim


20


A.




The non-rectilinear shape of the rims


16


and


20


serves to distribute the change in thickness between the main portion of the strip and the setbacks over a region which extends over a fraction of the length of the strip. In other words, this change in thickness is caused to be more progressive than if it were constituted as a rectilinear step, thereby preventing it from causing excessive local weakening of the strip.




The male members constituted by the studs


22


can be shaped so as to present a height that is slightly greater than the thickness E


12


. Consequently, when the two ends of the piece of strip are connected together, these studs can project a little through the openings


18


beyond the face


10


A, thus enabling them to be riveted against the face


10


A of the piece of strip, as can be seen in FIG.


4


.




The variant of

FIGS. 5 and 6

is generally analogous to that of

FIGS. 1

to


4


except that the first connection means shaped at the end


52


of the strip presents a larger number of openings


58


and the second connection means


54


shaped at the other end presents a larger number of studs


62


. The studs are naturally located in such a manner as to be capable of engaging in the openings


58


, with the exact positions of the studs and the openings being defined as a function of the desires of the person skilled in the art. For example, the studs and the openings in

FIGS. 5 and 6

are disposed at the four corners of a lozenge.




As in

FIGS. 1

to


4


, the rim


56


A of the overlap surface


56


remote from the free edge


52


A of the first end of the strip is not rectilinear. The rim


56


A constitutes a wedging rim suitable for co-operating with the free edge


54


A of the second end, which is of matching shape, and the free edge


52


A constitutes a wedging edge suitable for co-operating with the wedging rim


60


A of the overlap surface


60


.




As explained below, each of the connection means can be fitted with at least one male member and with at least one female member, these members being disposed in such a manner as to engage in one another so as to interconnect the ends of the strip. For example, in

FIG. 5

, the two orifices


58


A and


58


B in the vicinity of the two longitudinal ends of the surface


56


could be replaced by studs, while the two studs


62


A and


62


B could be replaced by openings for receiving said studs.




In the variant of

FIGS. 7 and 8

, the first connection means provided at the first end


112


of the piece of strip has a overlap surface


116


which extends over a width L


116


that is less than the width L of the main portion of the strip. Similarly, the connection means provided at the end


114


of the piece of strip presents a second overlap surface


120


extending over a width L


120


that is less than the width L of the strip.




The widths L


116


and L


120


are equal.




In the example shown in

FIGS. 7 and 8

, each of the connection means has two male members and two female members. For the connection means at the end


112


, the female members are constituted by two notches respectively referenced


118


A and


118


B disposed on opposite sides of the overlap surface


116


, in positions that are symmetrical about the longitudinal axis A of the piece of strip. For the second connection means at the end


114


, the female members are likewise constituted by two analogous notches, respectively referenced


115


A and


115


B.




The male members are constituted by projecting portions likewise disposed on opposite sides of the overlap surfaces. Thus, the first connection means forms a tongue whose sides carry two projecting studs near its free end, respectively referenced


113


A and


113


B, which studs are preserved during the operation used for locally reducing the thickness of the end


112


when shaping the setback whose surface forms the overlap surface


116


(with the side notches advantageously being cut out during this operation). Similarly the second connection means forms a tongue whose free end has two side studs respectively referenced


122


A and


122


B shaped like the studs


113


A and


113


B.




It will be understood that when the ends of the strip in

FIGS. 7 and 8

are assembled together, the overlap surfaces


116


and


120


are placed one against the other, with the studs


122


A and


122


B being received in the notches


118


A and


118


B while the studs


113


A and


113


B are received in the notches


115


A and


115


B. The connection means


112


and


114


are identical except that they are not formed in the same face of the piece of strip. In other words, the connection means


112


when seen from the first face


110


A of the strip is identical to the second connection means


114


when seen from the second face


110


B of the piece of strip.




In this embodiment, the faces


113


′A and


113


′B of the male members


113


A and


113


B that face towards the middle axis A of the piece of strip form wedging rims which cooperate with the longitudinal free edges


115


′A and


115


′B of the notches


115


A and


115


B to wedge the connection in the transverse direction. Similarly, the corresponding rims of the studs


122


A and


122


B perform the same function by co-operating with the longitudinal edges of the notches


118


A and


118


B.




Once the overlap surfaces have been put into place one against the other and the studs have been engaged in the notches, the connection can finally be bonded together by lightly deforming the studs, e.g. by clamping tending to move the two studs of either end towards each other. This deformation can also consist in flattening the studs in the radial direction so as to cause their free ends to partially overlie the adjacent face of the piece of strip (the face


110


A far from the surface


120


for the ends of the studs


113


A and


113


B, and the face


110


B far from the surface


116


for the ends of the studs


122


A and


122


B). The heights of the studs and the thicknesses of the setback portions are such that the total thickness of the connection, once made, remains substantially equal to the thickness of the main portion of the strip.




In the variant of

FIGS. 9 and 10

, it can be seen that the first connection means


152


has openings


158


analogous to the openings


18


and


58


described above, while the second connection means


154


has studs


162


analogous to the studs


22


or


62


.




This time, the second connection means


154


is so shaped that, when seen from above, it presents the form of a tongue of width L


154


that is smaller than the width of the piece of strip. Thus, the overlap surface


160


from which the studs


162


project extends over a fraction only of the width of the strip. Similarly, the overlap surface


156


in which the openings


158


are formed covers only a fraction of the width of the strip, and the outlines of the surfaces


160


and


156


are analogous.




Consequently, the rim


156


A of the overlap surface


156


not only presents an end wall remote from the free edge


152


A of the end


152


, but also side walls


156


′A extending generally along the longitudinal direction of the strip. When the two ends are connected together, the longitudinally extending edges


160


′A of the overlap surface


160


form wedging edges that co-operate with the side walls


156


′A so as to wedge the connection in the transverse direction of the strip.




Apart from these dispositions, the free edge


152


A can be convex in shape suitable for co-operating with the rim


160


A of the surface


160


remote from the free edge


154


A of the tongue which carries the second connection means. As for the variants shown in

FIGS. 1

to


6


, the variant shown in

FIGS. 9 and 10

could be modified so that each of the connection means has at least one stud and at least one female member.




In the variant of

FIGS. 11 and 12

, the first connection means formed at the end


212


of the piece of strip has a single female member constituted by a slot


218


of relatively large size. The second connection means at the end


214


has a single male member


222


of corresponding size. Depending on the desired result in terms of strength of the connection, it can be preferable to replace the substantially cylindrical studs of the type represented by the studs


22


in

FIG. 1

by a single stud of a different geometrical shape, e.g. an oblong stud, and correspondingly to replace the openings


18


by a single opening of matching dimensions. It can be desirable for the outline of this stud and of this opening to be given a particular geometrical shape, as is the case in

FIGS. 10 and 11

, where the stud


222


and the opening


218


have sinuous outlines respectively referenced


222


A and


218


A. The person skilled in the art can determine a suitable geometrical shape for the outline of the male member(s) and the female member(s) so as to increase the contact areas between said male and female members and direct the stresses that act between these members along desired directions.





FIG. 13

shows a variant which differs from the embodiments of

FIGS. 1

to


4


in that each connection means has one stud and one opening, respectively a stud


22


A and an opening


18


A for the first connection means


12


′, and a stud


22


B suitable for engaging in the opening


18


A, and an opening


18


B suitable for receiving the stud


22


A for the second connection means


14


′.




To make the connection between the two ends of the strip in the variant described above with reference to

FIGS. 1

to


13


, the two overlap surfaces defined in the setbacks at each of the two ends of the strip are placed one against the other, and the male and female members are mutually engaged. Thereafter, the male members are fixed to the female members, e.g. by riveting.




In the variant shown, the ends of the strip in the setback regions are of constant thickness, equal substantially to half the thickness of the main portion of the strip. Nevertheless, it is possible for the thicknesses of these ends in the setback regions to vary, e.g. in the form of steps or otherwise. The setbacks can be shaped by a stamping and/or embossing operation tending to flatten the strip locally with excess matter being pressed out, e.g. sideways, while leaving unflattened portions to constitute the male members and embossing locally to greater depths in order to form the female members, or forming through holes e.g. by punching.




The piece of strip used for making the crimping ring can be obtained by being cut out from a continuous strip.




It is then possible to begin by cutting off the piece of strip from said continuous strip prior to making the first and second connection means.




Alternatively, it can be preferred to make at least some of the connection means in the continuous strip prior to splitting it up into pieces of strip having said connection means.




In either case, it can be desired to make the first and second connection means completely prior to interconnecting the two ends of the strip and fixing the male members in the female members.




Alternatively, it may be preferred to make the male members in part only or not at all prior to connecting the two ends of the strip together so as to place the two overlap surfaces one on the other, with the male members being formed only once the strip is in this position. Under such circumstances, after the first connection means have been formed with its first overlap surface and the female member, this first overlap surface is placed against the second end of the piece of strip and pressure is applied in the region of the overlapping ends of the piece of strip in order to cause material constituting the second end of the piece of strip to be pressed out with a male member being embossed in said female member.




In particular,

FIG. 14

shows a variant in which the first connection means


252


is formed with the first overlap surface


256


and the female member constituted by a hole


258


. The second connection means


254


is formed merely as a second overlap surface


260


and the beginning of a male member


262


so as to define a very shallow projection from said overlap surface


260


.





FIG. 14

shows the situation in which the two overlap surfaces


256


and


260


have been placed against each other with the beginning of a male member


262


being in register with the female member


258


(into which it penetrates a short distance).




It can be seen that the second end of the strip presents a local excess quantity of material on its face


250


A remote from the second overlap surface. In the example shown, this excess material is shaped as a stud


262


′ which is in alignment with the beginning of a male member


262


on an axis perpendicular to the plane of the strip.




The first overlap surface


260


is generally obtained by stamping or embossing giving rise to local flattening with the flattened material being pressed out, so that by suitably arranging the embossing tool and backing tool, it is possible to select the most favorable position for this local excess quantity of material. It can be constituted, for example, by a local increase in thickness.




In the situation shown in

FIG. 14

, it suffices to apply sufficiently strong pressure to the side


250


A of the second end remote from the second overlap surface


260


in order to terminate formation of the male member by causing it to penetrate into the female member where necessary, treatment, such as heat treatment or quenching, can be initially applied to one of the two ends of the strip so as to ensure that the mechanical strength of the first end


252


is greater than that of the second end


254


in order to avoid said second end


252


being flattened when pressure is exerted to cause the male member to penetrate into the female member.




In the embodiments described above, the female members are made as through openings in the piece of strip, and the ends of the strip are connected together so that a male member is received in the female member and then said male member is deformed, e.g. by riveting as in

FIG. 4

, so as to fix it to said female member.




In

FIG. 15

, there can be seen the first connection means at the end


312


of a variant piece of strip. This first connection means is of the same type as the first connection means shown in

FIG. 1

, with elements referenced


316


,


318


,


312


A, and


316


A being analogous to the elements referenced


16


,


18


,


12


A, and


16


A, respectively.




As mentioned above, the setback whose surface forms the first overlap surface


316


can be made by locally flattening the end of the strip causing material to be pressed out in a controlled direction depending on the shape of the tool and the backing tool used. In

FIG. 15

, this material is directed outwards from the two longitudinally extending sides of the strip so as to form two side fins given respective references


319


A and


319


B disposed on either side of the overlap surface


316


. On their faces remote from the overlap surface


316


, the backs of these fins lie in the same general plane as the face


310


B of the strip. The thickness of the strip in the setback region as measured between the face


310


B and the overlap surface


316


is substantially about half the thickness of the main portion of the strip. The thickness of the fins is preferably less than that, e.g. about one-fourth the thickness of the main portion of the strip.





FIG. 16

shows the connection means at the second end


314


of the strip. It is analogous to the means


14


in

FIG. 2

, with the elements referenced


320


,


322


,


314


A, and


320


A corresponding respectively to the elements referenced


20


,


22


,


14


A, and


20


A. Thus, seen from the face


310


B of the piece of strip, the second connection means is analogous to that of FIG.


1


.




In contrast, seen from the face


310


A of the piece of strip which is remote from the overlap surface


320


, the second end of the strip has a step


321


whose depth is about one-fourth the thickness of the strip, for example. In this case, the thickness of the region of the strip defined between the bottom of this step and the overlap surface


320


is itself substantially equal to one-fourth the thickness of the main portion of the piece of strip. In

FIG. 17

, it can be seen that the two ends of

FIGS. 15 and 16

are assembled together by placing the two overlap surfaces


316


and


320


one on the other, engaging the male members


322


in the openings


318


, and then folding the fins


319


A and


319


B into the recess(es) formed by the step(s)


321


. In the example shown, the male members are also riveted in the female members. In

FIG. 17

, the step


321


covers the entire width of the strip, but that is not always necessary, it suffices for the strip to have two steps


321


suitable for receiving the folded-over fins


319


A and


319


B, and having substantially complementary shapes.




Alternatively, the first or the second end of the piece of strip could be provided with side fins analogous to the fins


319


A and


319


B without forming a step analogous to the step


321


in the other end. As a result, folding-over the fins tends to clamp the end of the strip which does not have fins and gives rise to local extra thicknesses of the strip in the connection zone. If the fins are of relatively small thickness, e.g. about one-fourth the thickness of the main portion of the strip, it will often be the case that this extra thickness does not interfere with subsequent use of the crimping ring, particularly during the crimping operation.





FIGS. 18 and 19

show certain steps of the method of obtaining the crimping ring.

FIG. 18

shows a continuous metal strip


410


having a group A constituted by the connection means


412


A at a first end of a piece of strip together with the connection means


414


A at the second end of an adjacent piece of strip formed simultaneously by a stamping and/or embossing operation. Thereafter, these two pieces of strip are separated along the line


413


which marks the boundary between the two connection means


412


A and


414


A. By way of example, these connection means can be analogous to those shown in FIG.


1


. It has been found that during the stamping and/or embossing operation, the metal of the strip is pressed out from the sides of the ends


412


A and


414


A. This pressed-out material can be used to form fins analogous to the fins


319


A and


319


B, or it can be preferable to remove them subsequently so as to obtain pieces of strip of the kind shown in FIG.


1


. Naturally, during the same stamping and/or embossing operation, it is possible to form a step of the type constituted by the step


321


, particularly when it is desired to retain the fins. At a given distance from the group A, another group A


1


is formed that likewise comprises a first connection means


412


A


1


for another piece of strip and a second connection means


414


A


1


which, once separated from the end


412


A


1


by cutting along the line


415


, will serve for connecting the crimping ring made from the piece of strip B, which piece of strip has connection means


412


A and


414


A


1


. By way of example, the group A


1


is shown as having another variant disposition of pressed-out matter obtained during the stamping and/or embossing operation. Excess matter in the pressed-out portions can be eliminated prior to cutting out the pieces of strip along the lines


413


and


415


, or otherwise, and indeed it is possible not to eliminate excess matter until after the strip has been rolled up.



Claims
  • 1. A crimping ring comprising a rolled-up piece of metal strip (10) whose two ends (12, 14; 52, 54; 112, 114; 152, 154; 212, 214; 252, 254; 312, 314) include respective first and second connection means that co-operate with each other to interconnect said ends,the ring being characterized in that the first connection means comprise a first overlap surface (16, 56, 116, 156, 256, 316) formed in the first end of the piece of strip as a setback from the first face of said piece of strip, together with at least one female member (18, 58, 118A, 118B, 158, 218, 258, 318) recessed from said first overlap surface, while the second connection means comprises a second overlap surface (20, 60, 120, 260) formed in the second end of the piece of strip as a setback from the second face of said piece of strip, together with a male member (22, 62, 122A, 122B, 162, 222, 262, 312) projecting from said second overlap surface, and in that the male member is engaged in the female member and fixed thereto while the overlap surfaces are placed one against the other so as to define a connection zone whose thickness (EZ) is substantially equal to the thickness (E) of the main portion of the piece of strip.
  • 2. A crimping ring according to claim 1, characterized in that each of the first and second connection means (112, 114) has at least one female member (118A, 118B, 115A, 115B) and at least one male member (113A, 113B, 122A, 122B).
  • 3. A crimping ring according to claim 2, characterized in that the first connection means (112, 12′) when seen from the first face of the piece of strip (110A) is identical 35 to the second connection means (114, 14′) when seen from the second face (110B) of the piece of strip (110).
  • 4. A crimping ring according to claim 1 or claim 2, characterized in that at least one of the first and second overlap surfaces (16, 20; 116, 120) is formed in a setback which has a wedging rim (16A, 20A; 113′A, 113′B), while the outline of the other one of the overlap surfaces presents a wedging edge (12A, 14A; 115′A, 115′B) co-operating with said rim to oppose forces directed transversely relative to the piece of strip (10).
  • 5. A crimping ring according to any one of claims 1 to 4, characterized in that the female member (18, 118A, 118B, 218) is formed by a through opening in the piece of strip (10) extending from the first overlap surface (16, 116).
  • 6. A crimping ring according to claim 5, characterized in that the female member is formed by a notch (115A, 115B, 118A, 118B) made in an edge of the first end of the piece of strip.
  • 7. A crimping ring according to any one of claims 1 to 6, characterized in that one of the first and second ends has a step (321) in its face (310A) remote from its face including the overlap surface (320), while the other one (312) of said first and second ends has side fins (319A, 319B) that are folded over into said step.
  • 8. A method of manufacturing a crimping ring in which first and second connection means (12, 14; 52, 54; 112, 114; 152, 154; 212, 214; 252, 254; 312, 314) are formed respectively at the first and second ends of a piece of metal strip (10), and in which these ends are connected together by making said first and second connection means co-operate with each other,the method being characterized in that a first setback is formed in the first end of the piece of strip from the first face thereof, the surface of the first setback defining a first overlap surface (16, 56, 116, 156, 256, 316), at least one female member (18, 58, 118A, 118B, 158, 218, 258, 318) is recessed from said first overlap surface, a second setback is formed in the second end of the piece of strip from the second face thereof, the surface of this second setback defining a second overlap surface (20, 60, 120, 160, 260), at least one male member (22, 62, 122A, 122B, 162, 222, 262, 312) is formed to project from said second overlap surface, the overlap surfaces are placed one against the other, the male member is engaged in the female member, and said male member is fixed to said female member, and in that the first and second setbacks are made in such a manner that the thickness (EZ) of the ring in the connection zone defined by the overlap surfaces disposed one against the other is substantially equal to the thickness (E) of the main portion of the piece of strip.
  • 9. A method according to claim 8, characterized in that the piece of strip is obtained by being cut out from a continuous strip (410) and in that the piece of strip is cut out prior to the first and second connection means being formed.
  • 10. A method according to claim 8, characterized in that the piece of strip is obtained by being cut out from a continuous strip (410), and in that prior to separating a first piece of strip from a following piece of strip by cutting (413, 415), the second connection means (414A) of a first ring is formed at the second end of the first piece of strip that is to constitute said first ring, and a first connection means (412A) of another ring is formed at the first end of the following piece of strip that is to make said other ring, and in that said pieces of strip are then separated by cutting (413) the strip between said first and second connection means.
  • 11. A method according to claim 8 or claim 9, characterized in that after at least the first connection means (252) has been formed with the first overlap surface (256) and the female member (258), said first overlap surface (256) is placed against the second end of the piece of strip and pressure is applied in the region of the overlapping ends of the piece of strip to cause the material (2621) of the second end of the piece of strip to be pressed out and to emboss a male member (262) into said female member.
  • 12. A method according to claim 11, characterized in that the first connection means (252) is formed with the first overlap surface (256) and the female member (258), the second connection means (254) is formed with the second overlap surface (260) and the beginning of a male member (262), the first and second overlap surfaces are placed one against the other with the beginning of a male member (262) being placed in register with the female member (258) and pressure is applied to the second end (254) of the piece of strip from its face (250A) remote from the second overlap surface (260) so as to finish off forming the male member, causing it to penetrate into the female member (258).
  • 13. A method according to any one of claims 8 to 12, characterized in that a female member (18, 118A, 118B) is formed as a through hole in the piece of strip, the ends of the strip are connected together so that a male member (22A, 122A, 122B) appears in said female member, and said male member is deformed in order to fix it to said female member.
  • 14. A method according to any one of claims 8 to 13, characterized in that a step (321) is formed in one of the first and second ends (314) of the piece of strip, in the face (310A) of said end that is remote from its overlap surface (320), the other end (312) of the piece of strip is fitted with side fins (319A, 319B), and in that the side fins are folded over into said step.
Priority Claims (1)
Number Date Country Kind
99 02477 Feb 1999 FR
PCT Information
Filing Document Filing Date Country Kind
PCT/FR00/00470 WO 00
Publishing Document Publishing Date Country Kind
WO00/50183 8/31/2000 WO A
US Referenced Citations (6)
Number Name Date Kind
210560 Robertshaw Dec 1878 A
410447 Rich Sep 1889 A
2273007 Cooper Feb 1942 A
2760262 Homan Aug 1956 A
5185908 Oetiker Feb 1993 A
5857659 Kato et al. Jan 1999 A
Foreign Referenced Citations (3)
Number Date Country
25 47 637 Apr 1977 DE
0 610 108 Aug 1994 EP
2 247 041 Feb 1992 GB