TECHNICAL FIELDThe invention relates to a device for assembly by crimping an appropriate connecting part of means to be assembled which can carry hydraulic, pneumatic or electrical energy.[0001]
In the context of the invention, the expression “connecting part” means that this particular part which is to be crimped is, for example, a ferrule, a union, a ring, a sleeve, a connector or other similar parts in which the area to be crimped is cylindrical.[0002]
Additionally, in the context of the invention, the expression “means to be assembled” relates to:[0003]
the rigid and/or flexible tubes which carry hydraulic or pneumatic power;[0004]
the ferrules associated with tubes and having at least one end crimped onto a tube and at least one other end forming a mechanical connection system such as, for example, a screw thread, a push-on fitting, a clip fitting, a rapid-action coupling, a glued fitting, a welded fitting, or other similar means;[0005]
mechanical cables for support, traction, or other types;[0006]
electrical cables carrying electrical power.[0007]
Also within the context of the invention, all these means to be assembled can be rigid and/or flexible, and can have two ends to be assembled by coaxial assembly, or more than two ends to be assembled, for example three ends in the case of a Y or T assembly, or, for example, four ends in the case of an X or + assembly.[0008]
The invention relates more particularly to a device for assembly by crimping an appropriate connecting part of means to be assembled having a complex shape before crimping.[0009]
The invention also relates to a device for assembly by crimping an appropriate connecting part of means to be assembled which can be incorporated into an automated industrial production system.[0010]
PRIOR ARTPower distribution circuits, such as hydraulic and pneumatic circuits, play a very important part in numerous fields of mechanical engineering.[0011]
Remote operation of various mechanical members under force can, for example, relate to:[0012]
robots operating on motor vehicle assembly lines;[0013]
civil engineering machinery, such as mechanical shovels, self-propelled pneumatic hammers, elevating platforms, self-propelled telescopic cranes or other devices;[0014]
extinguishing hoses;[0015]
plumbing hoses;[0016]
in the motor industry, power-assisted steering and braking and air conditioning;[0017]
domestic and/or industrial air conditioning;[0018]
in the field of aviation, landing gear lowering and retraction, and operation of brakes fitted to the wheels of landing gear. These various fluids are carried by tubing, of which some parts are rigid when they are located in installation areas not subject to mechanical movements, while the other parts are pliable and flexible when they are located in installation areas subject to mechanical movements such as translation, rotation of parts, or significant vibrations.[0019]
For example, the sealed joint between the terminal part of a rigid tube made from generally metallic material, and the end of a flexible tube made from a flexible material, possibly incorporating reinforcement consisting of a suitable support such as a textile, is generally made by forcible insertion of a limited length of the end of the rigid tube into an equivalent length of the flexible tube, and then by forcible crimping of the area of overlap of the two tubes, by means of a crimping connector surrounding the outer tube.[0020]
Crimping devices have been proposed for assembly by crimping an appropriate connecting part of tubes coupled at their ends, such as rigid and/or flexible tubes. These devices consist of the following, according to circumstances:[0021]
an assembly formed from teeth, or jaws, also called die segments, each tooth being separated from those around it by a means for keeping them in an open position and then momentarily bringing them together, and finally for their return to the open position, these teeth being arranged in a ring in an annular enclosure and being movable simultaneously by a radial movement to bring them into peripheral contact with the connector to be crimped and thus crimp it onto the coupled tubes which have been inserted axially into the ring formed by the teeth or jaws,[0022]
a mechanical means coaxial with the assembly formed from teeth, which acts on the teeth or jaws to displace them radially,[0023]
a hydraulic means acting on the mechanical means for causing the radial displacement of the teeth or jaws, in the form of a centripetal or centrifugal movement.[0024]
In a first vertical axis type (U.S. Pat. No. 4,527,414), the device for radially crimping a ring ([0025]51) onto an end coupling of tubes (50,52) consists of:
a base plate ([0026]11) pierced by a tapered opening (12) whose axial taper is oriented in the downstream direction of the device,
die segments ([0027]15) or jaws placed in the tapered opening and a separator (25) of the die segments mounted elastically in the downstream part of the tapered opening (12) which supports the die segments (15) or jaws in a circular ring, this separator and the die segments thus being displaceable axially,
a hydraulic assembly ([0028]24,30) positioned axially upstream of the base plate (11), acting in a downstream direction to push the die segments (15) or jaws downstream, in other words toward the smaller end of the tapered opening (12), in such a way as to produce a simultaneous radial movement of each die segment.
Thus the tubes ([0029]50,52), coupled at their ends and fitted with the ring (5) to be crimped, are introduced axially from the downstream end into the crimping device in such a way that the ring (51) to be crimped is positioned at the level of the die segments (15) which are displaced radially by the action of the hydraulic assembly (24,30) and crimp said ring. At the end of the crimping, the coupled and crimped tubes (50 and52) are extracted axially from the crimping device by a movement which is the reverse of that by which they were introduced.
Equivalent and very similar devices are described in patents U.S. Pat. No. 3,851,514 and GB 962094.[0030]
In another vertical axis type (U.S. Pat. No. 4,107,964), the device for radially crimping an appropriate ring onto tubes coupled at their ends comprises the following coaxial members:[0031]
an outer annular structure made from two parts ([0032]1) and (2) integral with each other, in which part (1) acts as a cylindrical hydraulic chamber, while within the downstream part of the outer annular structure there is a tapered annular part (11) integral with parts (1) and (2) of the annular structure, whose taper is orientated in the upstream direction of the device,
a movable annular part ([0033]4) whose inner surface is tapered, orientated in the upstream direction of the device, and whose outer surface is cylindrical and matched to the inner surface of the part (1) of the outer annular structure. This annular part (4) acts as a piston within part (1) of the outer annular structure, being displaced coaxially by the action of a hydraulic fluid (7) introduced into the hydraulic chamber delimited by the inner surface of part (1) and the outer surface of the annular part (4), and
die segments or jaws ([0034]8), located inside the annular part (4) and bearing on the upper annular surface of the tapered part (11), and held away from each other by springs (40) in contact with the inner tapered surface of the movable part (4).
The tubes, coupled at their ends and fitted with the ring to be crimped at the position of the coupling, are introduced axially (as in the first type of device), but, by contrast with the first type of device, through the upstream opening of the part ([0035]4), until the area to be crimped is at the level of the die segments or jaws (8). The pressurized hydraulic fluid is then admitted into the annular hydraulic chamber (7), causing the displacement of the piston part (4) which, because of its inner taper, causes the radial displacement of the die segments or jaws (8) and the crimping of the ring.
In another type with a horizontal axis (U.S. Pat. No. 3,977,065), the device for radially crimping an appropriate ring onto tubes coupled at their ends comprises the following coaxial members:[0036]
an outer cylindrical annular structure acting as part of a hydraulic chamber supplied by a hydraulic pump,[0037]
an annular part ([0038]22) within this outer structure, acting as a piston, its free end being shaped as a tapered annular chamber,
die segments or jaws ([0039]24) in contact with the wall of the tapered annular chamber (22) and bearing on one end of the outer cylindrical annular structure.
The tubes, coupled at their ends and fitted with a ring to be crimped at the position of the coupling, are introduced axially into the device until the area to be crimped is located at the level of the die segments or jaws ([0040]24). Under the action of hydraulic pressure, the annular part (22) acting as a piston is displaced, thus causing, by the taper of the annular chamber, the radial displacement of the die segments or jaws and the crimping of the ring.
In another type of radial crimping device (U.S. Pat. No. 5,323,697), the closed crimping ring device consists of:[0041]
a frame consisting of a fixed part ([0042]18) and a movable part (19) operated by two jacks (25,26) positioned perpendicularly on either side of the longitudinal axis (A-A) of the tubular part to be crimped,
an annular structure designed to receive the tubular part to be crimped, this annular structure being positioned in a cellular housing formed in the fixed part ([0043]18) of the frame, and in the movable part (19) of the frame, in such a way that the volume of the cellular housing is reduced as the movable part of the frame approaches the fixed part.
The annular structure located in the cellular housing consists of:[0044]
four guiding teeth ([0045]31,32,33,34) located at 90° to each other. Each of these guiding teeth (31,32,33,34) has a root consisting of two flat surfaces perpendicular to each other, bearing on complementary surfaces of the annular cellular housing. Two opposing guiding teeth (32,34) have one flat surface of each of their bearing roots sliding on the movable part of the frame, and one flat surface of each of their bearing roots sliding on the fixed part of the frame, in such a way that these two teeth approach each other simultaneously as the cellular space is reduced. One guiding tooth (33) is carried by the fixed part of the frame and another guiding tooth (31) is carried by the movable part of the frame,
four guided teeth ([0046]37,38,39,40) which are also positioned in the annular crimping structure. Each guided tooth is positioned between two common guiding teeth. Each guided tooth has a root consisting of two flat surfaces forming an obtuse angle of 135°, in such a way that each of the flat surfaces of the roots of the guided teeth bears in a flat sliding way on a complementary surface of a common guiding tooth.
When the movable part approaches the fixed part, the four guiding teeth simultaneously approach each other radially, thus pushing the roots of the guided teeth in an identical centripetal movement.[0047]
Clearly, this device has numerous major drawbacks. By way of illustration, some of these drawbacks are mentioned below:[0048]
the part to be crimped can only be inserted axially into the described device, and therefore parts which are bent or of complex shapes cannot be crimped,[0049]
the guided teeth are held by the guiding teeth by means of springs ([0050]55) connecting the common guiding teeth to the guided tooth to be held. The system of positioning by means of springs is inadequate because, in some cases, the guided tooth can remain jammed in the crimped part, causing it to be separated from the rest of the annular clamping structure. There is thus a marked lack of mechanical cohesion between the guided teeth and the guiding teeth.
All these prior art devices are based on the same principle in that:[0051]
the coupled tubes can only be introduced into the crimping area, for crimping their ends, along the axis of the device, in other words by introducing said tubes by a movement along the axis of the ring formed by the teeth or jaws, and access to the crimping area is therefore limited;[0052]
the axial positioning of tubes coupled at their ends for crimping is coaxial with the hydraulic means which radially displaces the teeth or jaws, and therefore the use and operation of the crimping devices is difficult;[0053]
the devices themselves, because of the principle of their design, cannot be used to crimp tubes coupled at their ends when one of the tubes is bent into a complex shape, such as a U or V shape, before crimping, although these devices are suitable for crimping a straight tube with an L-shaped bend in which the branch remaining free after the coupling is very short and can therefore be inserted into the crimping devices;[0054]
the crimping devices cannot be easily automated, and therefore cannot be incorporated in an automated industrial serial production system.[0055]
Another type of radial crimping device (JP 60141456) has a structure forming a frame ([0056]1) with a longitudinal axis, in which three faces can be opened to permit the access of the means to be assembled or crimped. A toothed means or set of jaws is positioned in the core of the device; these jaws consist of two groups of teeth which are identical to each other. A first group of teeth is fixed directly to a fixed part (2) of the frame (1) which forms a tooth support. A second group of six teeth is positioned on a movable mechanical assembly (3) which also forms a tooth support pushed by the jack (91).
Each of the teeth in these two groups has a base ([0057]201), (202), (301), (302), (401), (402), (501) and (502) perpendicular to the principal axis of the tooth. This base is shaped so that it can be coupled to the tooth support in such a way that the tooth can slide on this support in a movement parallel to its base. This assembly enables the teeth to be brought together when the jaw is clamped, while retaining an approximately coaxial arrangement of these teeth with respect to the axis of crimping.
The group of teeth positioned on the movable mechanical assembly ([0058]3) can be divided into three sub-groups of teeth.
A first sub-group of teeth consists of two teeth ([0059]65), (66), directly coupled to the jack (3) by the method of assembly used for the tooth bases described above. The two teeth of this sub-group are positioned radially opposite each other and on either side of the principal axis of thrust of the jack (91).
The other two sub-groups, each having two teeth, are identical to each other and are also positioned radially opposite each other and on either side of the principal axis of thrust of the jack ([0060]91). Each of these two sub-groups is positioned on a movable tooth support part (4), (5) fitted slidably on the planes (33), (34) formed in the movable part (3) at the end of the jack (91). These two planes which are formed are positioned symmetrically about the axis of thrust of the jack (91), and are inclined at 45° to this axis. The tooth supports (4) and (5) are coupled slidably to these two inclined planes in such a way that, when the crimping assembly is closed, the tooth supports lie flat on complementary surfaces (23), (24) which are equally inclined with respect to the axis of thrust and are positioned on the fixed frame opposite the jack (91). Thus, when the jack (91) is operated, the tooth supports simultaneously approach each other in a linear movement perpendicular to the axis of thrust of the piston (91).
The various groups of teeth (two teeth per group) supported respectively by the frame, the movable head of the piston and the movable tooth supports can thus be displaced radially to carry out the crimping operation.[0061]
One drawback of this device is that it requires the presence of two movable tooth support parts. The presence of these two parts makes it necessary to carry out a precise machining of all the surfaces for coupling the tooth supports to the frame and to the piston head.[0062]
Another drawback of this device is that the maximum lateral opening of the crimping device is limited by a major restriction formed by the teeth ([0063]63,68) near the lateral opening. This major defect limits the size of the parts that can be crimped when they are inserted laterally. In some cases, the presence of the teeth (63,68) restricting part of the lateral opening may cause damage to the parts to be crimped, and may result in rejection of products.
Another drawback of this system is that the crimping teeth are all fixed to their bases in such a way that they can be translated in only one direction along their supports. Thus the drawback of this solution is that it uses a large number of assemblies and a large number of coupled parts, thus complicating the manufacture of the device while also increasing the volume of the clamping device and the risk of its malfunctioning.[0064]
Each tooth is positioned by its base on its support by a plane to plane contact, resulting in an evident mechanical instability of the tooth during the clamping operation, and thus limiting the maximum clamping force transmissible through each tooth.[0065]
OBJECT OF THE INVENTIONA first object of the invention is to provide a device for assembly by crimping a connecting part of means to be assembled by their ends, thus providing improved access, particularly lateral access, to the crimping area, in other words to the ring formed by the crimping teeth.[0066]
Another object of the invention is to create a device for assembly by crimping a connecting part of means to be assembled, this connecting part possibly being a ferrule, a union, a ring, a sleeve, a connector or other similar device.[0067]
Another object of the invention is to create a device for assembly by crimping a connecting part of means to be assembled, where these means carry hydraulic, pneumatic or electrical energy, these means being rigid and/or flexible tubes, ferrules associated with these tubes and each having at least one end crimped on a tube while at least one other end forms a mechanical connection system such as, for example, a screw thread, a clip fitting, a rapid-action coupling, a push-on fitting, a glued fitting, a welded fitting, or other similar means, mechanical parts inserted in one tube and fixed by crimping a connecting part, or electrical cables.[0068]
Another object of the invention is to create a device for assembly by crimping a connecting part of means to be assembled, these means being mechanical cables for traction, support, or other applications.[0069]
Another object of the invention is to create a device for assembly by crimping a connecting part of means to be assembled, these means being rigid and/or flexible and possibly being extremely long, and possibly comprising two ends to be assembled coaxially or more than two ends to be assembled in the case of an assembly of a means of complex shape, for example a Y, T, X or + shape.[0070]
Another object of the invention is to create a device for assembly by crimping a connecting part of means to be assembled, this device being capable of forming crimpings with a precise diameter and with a precision which is maintained with repetition, by means of a “tool setting”.[0071]
Another object of the invention is to create a device for assembling, by crimping an appropriate connecting part, means to be assembled, where at least one of these means may have a complex shape before crimping, such as a shape represented by the letters U, V, Z, W or the symbol {square root}, where the bent part may be of considerable length.[0072]
Another object of the invention is to create a device for assembling, by crimping an appropriate connecting part, means to be assembled by their ends, this device being capable of being automated.[0073]
Another object of the invention is to create a device for assembling, by crimping an appropriate connecting part, means to be assembled, this device, since it is automated, being incorporated in an automated industrial serial production system comprising all the stages of manufacture and assembly of a finished article.[0074]
BRIEF DESCRIPTION OF THE INVENTIONAccording to the various objects stated above, the device according to the invention can eliminate the drawbacks encountered in the prior art and can also provide numerous advantages which were previously unavailable.[0075]
The device according to the invention for assembly by crimping a connecting part of means to be assembled is characterized in that it comprises:[0076]
a) a structure forming a frame with a longitudinal axis, at least three of whose faces permit the access of the means to be assembled into the core of said structure in directions perpendicular to said longitudinal axis.[0077]
b) a ring-shaped toothed crimping means in the core of the structure forming the frame, this means consisting of two toothed parts separable from each other and forming jaws, one of the toothed parts being placed in a fixed cellular housing created in the frame, and the other toothed part being placed in a cellular housing which is movable by longitudinal translation, said toothed means consisting of the two separable toothed parts[0078]
having an outer peripheral surface, created by the roots of the teeth, matching the inner peripheral surfaces of the two fixed and movable cellular housings on which the roots of the teeth bear,[0079]
creating an essentially cylindrical inner free reserve area for receiving connecting parts and means to be assembled, delimited by the cutting edges of the teeth which come simultaneously into contact with the connecting part to be crimped by radial displacement.[0080]
c) inside the frame, a means movable by longitudinal translation and carrying the appropriate movable cellular housing containing the movable toothed part which, in the open position, creates a transverse access passage from the periphery toward the core, between the two fixed and movable parts of the toothed means, and which, in the closed position, acts simultaneously with the fixed toothed part along a crimping axis perpendicular to the longitudinal axis.[0081]
DETAILED DESCRIPTION OF THE INVENTIONThe device according to the invention is designed in such a way that the toothed means forming a ring, consisting of two toothed parts separable from each other because of the movability of one of them, has a crimping axis perpendicular to the axis of displacement of the movable toothed part. This particular arrangement of the axes facilitates access through at least three of its faces to the core of the crimping device, in other words to the interior of the toothed means which opens into two pieces.[0082]
According to this particular design of the crimping device, the toothed means, consisting of the two fixed and movable parts, has the appearance of a toothed ring when in the closed position, with its height controllable because it is matched to the length of the connecting part to be crimped: this ring is easily interchangeable according to the type of ring used for the crimping.[0083]
Consequently, because of the ease of access, particularly lateral access, to the core of the toothed means which opens into two pieces, and the controlled height of the toothed means, the device according to the invention can crimp connecting parts, such as rings, on means to be assembled, such as tubes of very complex shape, coupled at their ends, these shapes being those required by the user's specifications and normally imparted to said coupled tubes after crimping when the crimping is carried out according to the prior art.[0084]
The toothed means forming a ring according to the invention consists of teeth of which some are guiding teeth and the others are guided teeth, alternating with the guiding teeth and bearing at least partially on the lateral surfaces of the guiding teeth.[0085]
The number of teeth present in the toothed means is generally an even number, there being as many guiding teeth as guided teeth: this number may be, for example, eight, where four teeth are guiding teeth and four are guided teeth.[0086]
Preferably, each of the two fixed and movable toothed parts forming the ring-shaped toothed crimping means has an odd number of teeth. Thus, in the case where the number of teeth in the ring is eight, the fixed part of the toothed means has three teeth, one being a guiding tooth, and the movable part of the movable toothed means has five, three being guiding teeth.[0087]
In each of the two fixed and movable toothed parts forming the ring-shaped toothed crimping means, the component guiding and guided teeth are linked together[0088]
by guiding means allowing their relative radial displacement in a single plane by the bearing of the lateral surfaces of the guiding teeth and the guided teeth, and their bringing together up to total contact of their lateral faces when the two fixed and movable toothed parts change from a separated, in other words open, state to a state of face-to-face contact, in other words the closed state, and consequently to a position in which the part for crimping is crimped at the “tool setting”;[0089]
by elastic means for separating or for returning the teeth when the two fixed and movable toothed parts change from a closed state at the point when the crimping operation is completed to an open state for which the movable toothed part is separated from the fixed toothed part, thus releasing the part crimped by the jaws and enabling it to be removed.[0090]
The fixed and movable toothed parts are placed in appropriate fixed and movable cellular housings, in such a way that each toothed part forms a jaw of which one of the guiding teeth is integral with the inner surface of the corresponding cellular housing.[0091]
Each guiding tooth has a base whose outer surface, opposite the cutting edge of the tooth itself, forms the root of said tooth.[0092]
The root of each guiding tooth in each of the fixed and movable parts of the toothed crimping means has an outer surface matching the inner surface of the fixed or movable cellular housing containing said parts, in such a way that said root of each guiding tooth, particularly those which are not fixed, bears and slides with its outer surface on the inner surface of the cellular housings containing it.[0093]
The inner surfaces of each of the fixed and movable cellular housings and the outer surface of the root of each guiding tooth can be surfaces having a cross section which is an arc of a circle or is approximately polygonal.[0094]
The inner surface of the fixed and movable cellular housings can be provided with interchangeable surfaces for the sliding of the roots which can be easily removed and changed, when, for example, frictional wear due to the action of the roots of the guiding teeth occurs.[0095]
Regarding the guiding and guided teeth of each of the fixed and movable toothed parts forming the toothed crimping means, these are dependent on each other in each of the two parts, in such a way that they can be displaced with respect to each other because of the presence of a guiding means and an elastic separation or return means. These two means enable them to be brought together until their lateral surfaces make contact, or to be moved away, according to whether the crimping device is being closed or opened:[0096]
the guiding means consisting generally of a set of guides, formed, for example, by cylindrical elements such as guiding rods, placed between the teeth in appropriate housings fashioned in said teeth,[0097]
the elastic means for separating or returning the teeth consisting, for example, of a set of helical springs mounted on the guiding rods.[0098]
Finally, the means movable by longitudinal translation, present within the frame and carrying the movable toothed part in the appropriate cellular housing, consists of a hydraulic, mechanical, pneumatic or electrical means. The movable means may be:[0099]
hydraulic, in which case it consists of a hydraulic system comprising a hydraulic chamber, a piston carrying the movable toothed part and moving longitudinally by translation in the direction of the closing or opening of the crimping device under the effect of a hydraulic pressure produced by a suitable hydraulic circuit comprising all the means required for its correct operation,[0100]
mechanical, in which case it can consist of a system comprising links, cranks and pinions,[0101]
pneumatic, in which case it can consist of a system comprising pressure multiplication jacks, or[0102]
electrical, in which case it can consist of a system comprising an electric motor and a screw and nut means.[0103]
Thus the device for assembly by crimping according to the invention is distinguished from the other prior art devices by:[0104]
the simplicity of its mechanical design, due to the presence of a toothed ring consisting of two parts, one fixed and the other movable, which facilitates the access, particularly lateral access, to the core of the crimping device,[0105]
its capacity for crimping tubes of very complex shape,[0106]
its capacity for crimping with precise, repeated and therefore reproducible diameters, owing to the fact that the crimping end stop is provided by the mechanical blocking caused when all the lateral faces of the guiding and guided teeth are brought into contact with each other, providing a “tool setting”.[0107]
Moreover, the crimping device according to the invention has proved suitable for incorporation in an automated serial production system, comprising all the stages of manufacturing and assembly of a finished article.[0108]