EP0350370A1 - Automatic tool for placing inserts, especially of the bushing type - Google Patents

Abstract

The tool (10), such as a pneumatic gun, places inserts, in particular inserts with a central hole, one by one. An insert loader (5) is slidable in the front end (2) of the tool body and comprises a longitudinal channel (52) and a lateral insert-injecting channel (53) which communicate with one another via an orifice (57). A push rod (6) is slidable in the longitudinal channel and may possess a gripping device (66). A piston (23) of a single-acting pushing cylinder (2) is integral with the loader and advances the loader (5) which opens the orifice (57) for the passage of an injected insert (1) which is stopped by retractable lugs (54). A spring (25) moves the loader (5) back so that the stopped insert is held by the gripping device (66), and that the lugs (54) are retracted by the push rod (6). Finally, the held insert (1) is completely visible at the front of the tool (10) in order to centre it on the hole of a component. The push rod (6) is immovable as the loader (5) is moved forward and back, and is struck by the rod of a rear piston in a single-acting cylinder with compression chamber counter to a return spring, in order to implant, with a very high force, the held insert into the component hole. <IMAGE>

Description

The present invention relates to the installation of an insert, of the metal sleeve type with or without a tapped or smooth central hole, optionally expandable and comprising one or more longitudinal slots, in order to implant the insert in a perforated hole of a piece of soft or hard material, such as wood or plastic, and thus make a resistant hole in this piece. When the hole in the insert is tapped, it is suitable for receiving a threaded rod, a screw, or similar connecting element. When the hole of the insert is smooth, it is intended to receive a smooth end of a rod, a centering pin, a dowel, a pivot, a journal, or element of analogous bond. When the insert does not have a hole, it can be used as a pin or centering pin.

More particularly, the invention relates to an automatic device for fitting inserts as defined in the preamble of claim 1.

Such a fitting device is described in patent application FR-A-2595609 in the name of the applicant. This device is intended for fitting expandable threaded sockets comprising a grooved head and a knurled slotted lower part having a smaller diameter and forming with the head a circular shoulder. The device charger is stationary and attached to the body of the device. At the front of the longitudinal duct, the loader is provided with two retractable pivoting jaws to stop an insert injected by its shoulder. At rest, the front end of the push rod, known as the anvil, is set back from the orifice of the lateral injection duct in order to release the latter for the passage of the injected insert. Then, in a second step, the push rod is moved forward in the longitudinal duct in order to retract the jaws and push the insert into the pre-punched hole of a part.

Before inserting the insert, the lower part of the insert retained by the jaws protrudes slightly from the front of the unit and approximate the axis of the insert to the mouth of the workpiece hole.

However, if the lower part of the insert is small, or a fortiori if the insert does not have a shoulder, the insert stopped by the jaws is completely located inside the front end of the device and is invisible from the outside. The front end of the device, when it is portable, can only be very approximately centered above the hole in the workpiece, which implies a risk of misalignment of the implant inserted with the hole in the part and, consequently, a risk of degradation of the part around the mouth of the hole. In addition, for the implantation of an insert, in particular without a shoulder, the lower base of which is stopped by the jaws, the front end of the device must be held approximately above the mouth of the part hole, without contact with it, in order to allow the jaws to pivot when the push rod is pushed.

This is why, in order to avoid these drawbacks, the installation device according to FR-A-2595609 is in practice kept vertically at a fixed station in a support, and the part which is to receive the insert is positioned precisely in a cartable vice in order to align the hole of the part below the axis of the longitudinal duct of the loader containing the injected insert.

Another fitting device also comprising an insert charger fixed to the body of the device and provided at the front with retractable levers to stop an injected insert is also disclosed in patent application FR-A-2165813. This device is intended to install rivets having an expandable head and tabs. The tongues form an intermediate shoulder with the head to be retained by the retractable levers and are expandable by means of a peg initially linked on the top of the head of the rivet. This device has the same drawbacks as those of the device according to FR-A-2595609.

A third installation device of the same type as the previous ones is also described in FR-A-1201222. The charger for this device itself constitutes the body of the device. The push rod slidingly mounted in the magazine is also rotated so that the front end of the push rod is translated and rotating simultaneously and therefore that the device constitutes a screwdriver, the inserts being screws. Insert retaining jaws are also provided on the front of the magazine.

These three devices thus have in common a single command for sliding movement of a push rod in the body of the device in order to directly install an insert stopped by the jaws or retaining levers.

In particular, these three devices do not allow the front end of the device to be pressed against the mouth of the perforated hole in the part, by means of the insert retained by the jaws or retaining levers, before activate means for advancing the push rod so that it closes the passage orifice between the longitudinal duct and the lateral duct in the magazine and pushes the insert into the perforated hole of the part. Indeed, the insert is retained by the jaws or levers only by the gravity effect of the insert, and any application of the insert retained against the workpiece causes the insert to rise in the longitudinal duct and thus the cover for its alignment with the hole of the part. Of course, to allow proper support of the front end of the device against the workpiece, the jaws or levers could be eliminated and their stop function would be replaced by the mouth of the workpiece hole, as recommended by the DE-A-2920410. In this case, it is obvious that the stopped insert is not visible and that the device must be used in a fixed position on a micrometric work table.

The present invention therefore aims to provide an inserting device preferably portable insert by means of which the injected insert is kept completely visible in front of the front end of the device so that the insert is aligned and pressed visibly on the 'mouth of the pre-punched hole in the part, prior to any movement of the push rod and therefore any push exerted by the push rod to implant the insert in the part. The device thus offers two independent operating steps: first to capture and make visible an insert, and the second to implant the captured insert.

To this end, an apparatus for fitting inserts with a central hole is as characterized in claim 1.

Thus in the installation apparatus according to the invention, the means for gripping which may be constituted by flexible strips according to claim 3, or by a nipple with a longitudinal slot according to claim 5 forming a clamp insertable into the central hole of an insert, keep the insert visible at the end of the device both by convergent radial force exerted around the insert or diverging exerted in the hole of the insert as by abutment against the front end of the push rod. The device can therefore be held in any position, including with its front end directed or inclined upwards, during the alignment of the inserted insert with the perforated hole in the part and the implantation of the insert in the hole. This advantage facilitates the precise positioning of the insert on the mouth of the part hole, and the support of the device against it during the very high subsequent thrust of the insert by the push rod in the room. In addition, the insert can be positioned vertically under a hole in a part whose mouth is directed downward, positioning which is impossible with the three devices known according to FR-A-2595609, FR-A-2165813 and FR-A-1201222.

According to a preferred embodiment of the invention, the means for moving the charger relative to the body of the device, but also relative to the push rod, are preferably as defined in claims 7 and 8.

The invention also aims to very quickly implant an insert in the hole of a part, and consequently to communicate to the push rod a very high implantation force in order to implant the insert without vibration whatever the practically hardness of the part. To this end, the apparatus comprises, at the rear, means for striking and advancing the push rod in order to implant the insert inserted in a hole of a part having a diameter substantially smaller than the external diameter of the insert, and second means elastic, such as expansion of compressed air in a compression chamber, to move the push rod back.

Unlike the push rods of known setting devices where the push rod constitutes the rod of a piston of a jack, which, by nature, is driven at a slow speed, the push rod according to the invention does not is not linked to a piston rod, but is struck by the rod of a second piston, or by the front face of a second piston sliding on an axis, in a single-acting cylinder with compression chamber and expansion, substantially at the end of the advance stroke of the second piston. Thus prior to percussion, the second piston is practically not subjected to any force and is capable of acquiring a high speed and consequently of communicating at the end of the race, by elastic shock, a very high force to the rod. pusher. The insert is thus implanted by a powerful one-touch of the second piston against the push rod. This implantation follows an activation of the means for striking independent of the prior activation of the means of displacement of the charger.

• - la Fig. 1 est une vue longitudinale partiellement en coupe axiale d'un insert du genre douille taraudée expansible, positionné sur l'embouchure d'un trou préperforé de pièce ;
• - La Fig. 2 est une vue de côté partiellement en coupe d'un appareil de pose d'inserts selon une première réalisation de l'invention, sous la forme d'un pistolet pneumatique, l'intérieur d'un cylindre arrière de piston de percussion étant montré schématiquement en coupe ;
• - les Figs. 3A et 3B sont des vues détaillées en coupe longitudinale de dessus des parties avant et arrière du corps de l'appareil montré à la Fig. 2, contenant un chargeur coulissable et le cylindre du piston de percussion en position de repos, respectivement ;
• - la Fig. 4 est une vue détaillée en coupe longitudinale de l'extrémité avant de l'appareil montré à la Fig. 2, le chargeur étant en fin de course d'avance pour retenir un insert injecté ;
• - la Fig. 5 est une vue analogue à la Fig. 4, le chargeur étant sensiblement à mi-course de recul, lors de la saisie d'un insert par une pince en bout de tige-poussoir ;
• - la Fig. 6 est une vue analogue à la Fig. 4, le chargeur étant au repos, en fin de course de recul, pour maintenir visiblement à l'extérieur un insert à implanter ;
• - la Fig. 7 est une vue en coupe prise le long de la ligne VII-VII de la Fig. 8, analogue à la Fig. 6, et montrant l'extrémité d'un chargeur au repos, selon une autre réalisation ;
• - la Fig. 8 est une vue en bout avant du chargeur de la Fig. 7 ;
• - la Fig. 9 est une vue longitudinale de face d'une lamelle-ressort de retenue et saisie d'insert incluse dans le chargeur de la Fig. 7 ; et
• - la Fig. 10 est une vue détaillée en coupe longitudinale, analogue à la Fig. 3B, d'une partie arrière de corps d'appareil selon une autre réalisation, contenant un cylindre pour second piston de percussion à coulissement axial, ledit piston étant en position de repos.

Other characteristics and advantages of the invention will appear more clearly on reading the following description of several preferred embodiments of the invention with reference to the corresponding appended drawings in which:

• - Fig. 1 is a longitudinal view partially in axial section of an insert of the expandable threaded sleeve type, positioned on the mouth of a prepunched part hole;
• - Fig. 2 is a side view partially in section of an inserting device according to a first embodiment of the invention, in the form of a pneumatic gun, the interior of a rear cylinder of percussion piston being shown schematically in section;
• - Figs. 3A and 3B are detailed views in longitudinal section from above of the front and rear parts of the body of the apparatus shown in FIG. 2, containing a sliding magazine and the cylinder of the percussion piston in the rest position, respectively;
• - Fig. 4 is a detailed view in longitudinal section of the front end of the apparatus shown in FIG. 2, the loader being at the end of the advance stroke to retain an injected insert;
• - Fig. 5 is a view similar to FIG. 4, the charger being substantially at the mid-point of the recoil, when gripping an insert by a clamp at the end of the push rod;
• - Fig. 6 is a view similar to FIG. 4, the charger being at rest, at the end of the recoil stroke, to visibly maintain an insert to be implanted outside;
• - Fig. 7 is a sectional view taken along the line VII-VII of FIG. 8, similar to FIG. 6, and showing the end of a charger at rest, according to another embodiment;
• - Fig. 8 is a front end view of the charger of FIG. 7;
• - Fig. 9 is a longitudinal front view of a retaining spring leaf and insert insert included in the loader of FIG. 7; and
• - Fig. 10 is a detailed view in longitudinal section, similar to FIG. 3B, of a rear part of the device body according to another embodiment, containing a cylinder for a second percussion piston with axial sliding, said piston being in the rest position.

By way of example, an insert 1 capable of being installed by a delivery device according to the invention is illustrated in FIG. 1 in the form of a cylindrical threaded and expanding brass bushing.

The insert 1 comprises an upper portion 11 and a lower portion 12 shared by a peripheral annular groove 13. The upper portion 11, called the insert head, offers external longitudinal grooves 14, while the lower portion 12 has a cylindrical surface knurled external 15 with sharp pyramidal points. The lower portion of the insert can be terminated by a short circular centering stud 16, cylindrical or frustoconical, having a small height and a diameter substantially smaller than that of the knurled surface 15. The stud 16 serves to center the insert on the mouth of a cylindrical hole T, blind or transverse, of a piece P of soft material such as wood, or of harder material such as plastic, before introduction of the insert into the hole, as will be seen below. The diameter of the hole T is between the external diameter of the insert and the diameter of the centering pin 16.

The insert 1 also has an axial threaded bore 17 over the entire length of the insert. Two longitudinal slots 18 are formed in a diametrical plane of the insert 1 and extend from the centering stud 16 to the groove 13 or substantially beyond the latter.

According to other embodiments, an insert intended to be installed by an apparatus according to the invention has no longitudinal slot or has more than two longitudinal slots, and has a smooth axial bore, or a threaded bore in the upper portion 11 and smooth in the lower portion 12, which can be terminated by a frustoconical or ogival longitudinal section, opening or blind. The diameters of the portions 11 and 12 can be equal, as shown in FIG. 1, or the diameter of the upper portion 11 may be substantially greater than that of the lower portion 12. The groove 13 or any other shoulder between the portions 11 and 12 can be eliminated. All types of grooves and points or teeth can be provided both on one and on the other of the portions 12 and 13, one of these portions being able to be smooth. These grooves and / or teeth serve, in a known manner, to immobilize at least in axial rotation the insert in the hole T of the part P in which a tapping or resistant hole is to be made.

According to other variants, as will be seen below for the type of device shown in Figs. 7 to 9, the insert may not include a central hole 17, or may offer a smooth or tapped blind central hole opening into an upper 11 or lower 12 portion.

As shown in Fig. 2, an automatic device for inserting inserts according to the invention comprises a body 10 essentially constituting the barrel of a pneumatic gun provided with a stock 101. The device body 10 is essentially composed of tubular and cylindrical elements - or with a square or polygonal section - arranged coaxially to a longitudinal axis YY ′ of the device. Seen from the outside, the device body 10 comprises three main cylindrical elements which can be dismantled, namely a first pneumatic single-acting pushing cylinder 2 at the front, a second single-acting pneumatic cylinder 3 at the rear, and a cylindrical adaptation support 4 located between the cylinders 2 and 3.

With reference to FIG. 3A, the front cylinder 2 comprises a front longitudinal bore 20 and a rear longitudinal bore 21 which are separated by an intermediate internal shoulder 22.

The rear bore 21 forms a chamber in which slides a head of the first piston 23 with recessed O-ring 230. The piston head 23 slides between a rear countersinking 210 of the bore 21 and the rear end of a stop ring 24 which is forced into the front bottom of the bore 21, against the shoulder 22. The thrust exerted forward by the first piston is created by compressed air introduced by a flexible pipe 70 (Fig. 3B) which is connected to an adjustable elbow fitting 40 fixed laterally to the support 4 and opening into the counterbore 210 through a small bent conduit 41 formed in the body of the support 4. The first piston is returned to the rest position shown in the Fig. 3A by means of a helical spring 25 which is housed coaxially around the hollow rod of the first piston 26 and partially in the stop ring 24. The front and rear ends of the spring 25 are applied against the fixed shoulder 22 and the head of movable piston 23, respectively.

In the front bore 20 of the cylinder 21 is slidably mounted an insert magazine 5 secured to the front end of the first piston rod 26. The body of the magazine constitutes a connection at approximately 30 ° and with three branches.

A first branch at the rear of the loader 5 has a threaded bore 51 into which the threaded front end 261 of the first piston rod 26 which is screwed through the shoulder 22 internal to the cylinder 2 is screwed.

A second branch at the front of the loader 5 has a bore 52 which extends from the bottom of the bore 51 of larger diameter, a longitudinal bore 262 passing through the entire rod 26 and the head 23 of the first piston. In the butted bores 52 and 262 coaxial with the axis YY ′ is mounted to slide a long cylindrical push rod 6. At the front end of the second branch of the charger are provided three insert retaining lugs 54 embedded in three radial holes 55 of the charger and distributed axially. An external annular spring 56 made of rubber applies the lugs 54 against annular abutment shoulders which are internal to the holes 55 and which are flush with the bore 52. The annular spring 56 is housed in an external groove of the second branch of the loader and in V-grooves on the lugs 54. The internal ends of the lugs are spherical and project into the bore 52 under the pressure of the spring 56 in order to stop an insert injected by the third branch of the loader, or are applied against the cylindrical periphery of the push rod 6 when the latter slides in the bore 52, as will be seen below.

A third branch of the loader 5 comprises an insert injection bore 53 which is inclined at an angle of approximately 30 ° with the first branch 51 and which communicates with the bore 52 through an orifice 57 lateral to the latter . The internal diameters of the bores 52 and 53 of the magazine and the external diameter of the push rod 6 are substantially greater and less than the external diameter of the insert 1, respectively. The rear end of the bore 53 is widened and tapped to receive a threaded connection 58 of a flexible plastic sheath 580 in which the inserts are pneumatically transported one by one from a reserve of inserts. The insert injection sheath 580 is bent to be guided in a collar 582 which is fixed to a lateral rib 583 on the pistol grip 101 by screw and nut 584, as shown in FIG. 2. The third branch of the loader slides in a groove 27 longitudinal to the bore 20 and formed in the cylinder 2 in front of the shoulder 22 which acts as a rear stop for the loader 5 and therefore also for the first piston 23-26 secured to the loader .

The reserve of inserts (not shown) is of a known type comprising a vibrating bowl containing loose inserts, mounted on a high frequency vibrating system by electromagnet, and provided with a pneumatic slide selector. The selector is connected to the other end of the insert injection sheath 580 and ensures the one by one distribution of the inserts. The injection of an insert is controlled at the level of the inserting device, by means of a pneumatic micro-distributor 7 with push-button 71, as shown in FIG. 2. The micro-distributor 7 is connected to a pressurized air inlet sheath 72 through a fitting 73 fixed to the rear of the stock 101, an internal pipe to the stock and an elbow fitting 74 fixed laterally on the butt, and is connected to flexible exhaust pipes 70 and 75 through a T-connector 76. The pipe 70 serves, as already said, the chamber 21 in the cylinder 2 through the conduits 40, 41 and 210, and the line 75 is connected to the selector drawer. When the push button 71 is pressed, the pressurized air passes through the T-connector 76 and simultaneously causes the injection of an insert into the sheath 580 from the selector of the vibrating bowl, and the push of the head first. piston 23 to advance the magazine 5.

With reference to Figs. 3A and 3B, the adaptation support 4 offers at the front a part in the form of a threaded thin ring 42 inside which a rear base 27 of the single-acting cylinder 2 is forcibly slid and on which is screwed a threaded connection nut 28 pushing the base 27 against the bottom of the part 42. At the rear, the adaptation support 4 offers a collar 43 which is clamped by screws 431 and internal O-ring 432 against the front base of the second single-acting cylinder 3. At the flange 43 is provided a frustoconical counterbore 44 in the body of the support 4 to receive a ring 30 forming a stopper for end of travel before the head 31 of a second piston sliding at inside of a jacket 34 of the cylinder 3. The front stopper 30 is immobilized against the counterbore 44 by means of a stop ring 35 surrounding the rear of the stopper 40, abutting against a shoulder thereof, and having a collar applied against the support collar 43 by the front base shirt ant 34.

Between the front ring part 42 and the rear counterbore 44 is formed coaxially with the axis YY 'a double bore chamber 45-46 delimited at the rear by the stopper 30. In the rear bore 45 of this chamber is mounted sliding a rear head 61 of the push rod 6, while against the bottom of the front bore 46 of larger diameter of this chamber is applied a helical compression spring 62 pushing the head 61 towards the front face of the stopper 30. The advance travel of the rod head 61 is limited by an elastomer washer 63 which is force-fitted into the bottom of the bore rear 45 and the thickness of which is chosen as a function of the penetration height of an insert in a part hole T, and incidentally of the height of the insert 1. The elastomer washer 63 is force-fitted around a small thin metal reinforcement ring 631 so that, during the damping produced by the washer 63 at the end of travel before the rod head 61, as will be seen below, the sensitive crushing of the washer 63 n 'not obstruct the relaxation of the spring 62 to return the rod head 61 backwards. The push rod 6 slides in an intermediate shoulder 47 internal to the support 4. The shoulder 47 is located between the threaded front part 42 and the bore 46 and contains an O-ring 48.

According to another variant, the spring 62 can be replaced by a stack of Belleville washers, or by a spring located at the rear of the head 61 and in a hole in the stopper 30 to act in traction when the head 61 returns. .

According to the embodiment illustrated in Figs. 3A and 3B, in a long blind cylindrical hole 64 at the rear of the rod 6, of the order of approximately 30 to 70 mm, penetrates the front end 33 of the second piston rod 32 in the cylinder 3.

As shown in Figs. 2 and 3B, the O-ring head 31 of this second piston is screwed to the threaded rear end of the rod 32 and slides in the cylindrical jacket 34 between a rear stopper 36 secured to a cap 37 clamped by screws and closing l 'rear of the cylinder 3 and the device body 10, on the one hand, and the rear face of the stopper 30, on the other hand. The reciprocating stroke of the second piston is triggered by a trigger 38 controlling a distributor 39 which is fixed under the cylinder 3, as shown in FIG. 2. The distributor 39 is connected on the one hand to the compressed air inlet sheath 72 through the butt 101, on the other hand to intake 341 and exhaust 342 conduits located at the stopper 36 , at the back of the shirt 34 and therefore behind the rod head 31. A chamber 343 completely hermetic delimited mainly by the jacket 34 between the buffers 30 and 36 and in front of the head 31 in the rest position is filled with a gas, such as air, and communicates with an annex chamber 344 between the body of the cylinder 3 and the front of the shirt 34 by small radial front vents 345 formed in the shirt. As will be seen below, during the thrust of the head 31 exerted by the pressurized air arriving through the sheath 72 and the intake pipe 341 following the pressing of the trigger 38, the air from the chamber 343 is compressed in chamber 344, then when the trigger 38 is released, the expansion of the air coming from chamber 344 towards chamber 343 causes the piston head 31 to recede, and the exhaust of the air behind the head 31 through the exhaust pipe 342 and outwards.

According to another variant, the elastic expansion of the air in the chambers 343 and 344 is replaced by a compression or tension spring for example.

At rest, as shown in Figs. 2 and 3B, the piston head 31 is applied against the rear stopper 36, and the front end 33 of the piston rod 31 penetrates a few millimeters into the hole 64 of the push rod 6 which is applied against the front face of the stopper 30 by the spring 62. The distance D1 between the bottom 65 at the front of the hole 64 of the push rod 6 at rest and the front end 33 of the piston rod 31 at rest is substantially less than the stroke maximum of the second piston in the cylinder 3, but is large enough so that the second piston can reach a high acceleration before the rod end 33 reaches the bottom of the hole 65 and consequently can communicate by percussion a sufficient high power to the push rod 6 to forcefully insert an insert into the part hole T. It should be noted that the long hole 64 makes it possible to reduce the length of the device 10, and incidentally to guide the piston rod 32.

According to the embodiment shown in Figs. 2 to 6, the front end of the push rod 6 comprises means for gripping a perforated insert, such as that 1 shown in FIG. 1, through the hole 17 at least in the upper portion 11 of the insert 1. The means for gripping are here in the form of a substantially spherical stud 66 which is provided with an axial slot 67 in order to form an expandable clamp, and which projects at the front end 68 of the push rod 6. In the idle state of the inserting device, practically alone the stud 66 protrudes at the front end of the device, when the head 61 of the push rod is applied against the stopper 30 by the spring 62 and the rear face of the charger 5 abuts against the shoulder 22 of the cylinder 2 by return of the spring 25. The diameter of the bore 17 of the insert 1 is substantially equal to the diameter of the clamp 66, and preferably is substantially less than the diameter of the clamp 66 at rest, when the slot 67 has a width uniform, and is substantially greater than the diameter of the clamp 66 when the latter is tightened and the slot 67 is therefore closed at the front.

According to another variant, the clamp 66 can be replaced by a grooved stud supporting a flat loop spring, as described in French patent application No. 88-11750 filed on September 8, 1988 in the name of the applicant.

The fitting of an insert 1 by means of the device 10 for fitting inserts illustrated in FIGS. 2, 3A and 3B are carried out in two distinct stages. A first step consists in loading an insert at the visible front end 66 of the push rod 6 through the charger 5. A second step consists in introducing the loaded insert into the hole T of the part P by percussion of the second piston rod 32 against the push rod 6. During these two stages, the device body 10 can remain immobile, if it is installed in a fixed position.

The loading step consists essentially of the successive forward and backward strokes of the first piston 23-26 and of the loader 5 and therefore of the sliding of these integral elements in the cylinder 2 of the device body 10, as illustrated in FIGS. . 4, 5 and 6, from the rest phase shown in FIG. 2. These two strokes are controlled by depressing and then releasing the button 71 while keeping the gun with its front end free, and therefore spaced from the part P, so that the magazine 5 can freely slide in the bore 20 and the groove 27. During the entire loading step, the second piston 31-32 is not not stressed and the push rod 6 is immobilized by return of the spring 62 against the stopper 30.

The loading step is initialized by depressing the button 71 which simultaneously controls the supply of compressed air to one part of the pipe 70 to cause the first piston 23-26 to move forward under the pressure of air in the counterbore 210, on the other hand of the pipe 75 to cause the opening of the selector drawer associated with the vibrating bowl of reserve of inserts and the blowing of an insert 1 in the sheath 580.

During the routing of the insert injected 1 into the sheath 580, the loader 5 secured to the rod 26 of the first piston slides forward, according to the arrow CA in FIG. 4, by axial guidance in the front bore 20 and the longitudinal groove 27 of the first cylinder 2 and around the front portion of the push rod 6. At the start of the feeder advance 5, the retaining pins 54 cross the clamped front end 66 of the stationary push rod 6 and are returned radially over approximately 1 mm towards the central axis YY ′ and in abutment against the internal shoulders of the radial holes 55 by the annular spring 56 so that the ends hemispherical lugs protrude into the bore 52 of the magazine. The end of stroke C5 of the first piston 23-36 and of the magazine 5, indicated in Figs. 3 and 4, is defined by the stop of the piston head 23 against the rear base of the ring 24 in which the spring 25 is compressed.

At the end of the feeder advance travel, as shown in Fig. 4, the first branch with threaded bore 51 is positioned on the front end of the push rod 6 and surrounds the clamp 66 which is behind the insert passage orifice 57. The orifice 57 is thus completely free from the front end of the push rod 6 so that the insert 1 injected into the sheath 580 arrives, after the end of advance travel of the loader 5, in the third loader branch 53, passes through the orifice 57 and either stopped by the hemispherical ends of the three lugs 54, following the path of the arrow IN in FIG. 4. At this stage, the front base 16 of the insert 1 is in contact with the lugs 54, and the insert 1 is arranged coaxially in the bore 52 in front of the clamp 66 set back in the first branch 51.

The release of the button 71 opens an air exhaust orifice in the distributor 76 and causes a vacuum in particular in the cylinder chamber 21 at the rear of the piston head 23. The head 23 is then returned towards the rear by the spring 25 until the first branch 51 of the charger 5 abuts against the internal shoulder 22 at the end of the recoil stroke.

During this reversing stroke following the arrow CR, as shown in FIG. 5, the insert 1 is transported by the charger 5 in the direction of the stationary push rod 6. Noticeably at half of the feeder's recoil stroke, the axial hole 17 of the insert 1 slides frictionally around the clamp 66, by narrowing the slot 67 thereof, under the rear thrust exerted by the pins 54 , until the rear face of part 11 of the insert abuts against the front end 68 of the push rod 6 and the insert completely contains the clamp 66.

During the end of the magazine 5's recoil stroke, the lugs 54 are retracted radially towards the outside of the magazine and slide, under the action of the annular spring 56, against the periphery of the insert 1 gripped by the tight clamp 6, then against the cylindrical front end of the push rod 6. At the end of the magazine recoil stroke, as shown in FIG. 6, when the first branch 51 of the loader abuts against the shoulder 22, the insert 1 is abutted at the front end of the push rod 6, held by the elastic spacing of the clamp 66 in the bore insert 17, and completely protruding from the second lug leg of the magazine 5, the push rod 6 completely passing through the axial bore 52 of the magazine and closing the insert passage orifice 57, as shown in FIGS. 3 and 6.

Then the centering pin 16 of the gripped insert 1 completely visible at the end of the device 10 is pressed axially on the mouth of the hole T of the part P. The hole T can open upwards, as shown in FIG. . 1, or lead down, or can be tilted.

The second step is triggered by the actuation of the trigger 38 of the gun which, through the distributor 39, causes the advance stroke towards the front, then the recoil stroke towards the rear of the second piston 31-32 which slides in cylinder 3 of device body 10. During this second step, the first piston 23-26 and the charger 5 are immobilized in abutment against the shoulder 22 of the cylinder 2 under the action of the return spring 25. Referring again in Figs. 3A and 3B, during most of the advance stroke D1 of the second piston 31-32, the second piston is pushed forward in the jacket 34 of the rear cylinder 3, and the rod 32 penetrates without friction or at very slight friction in the hole 64 of the push rod 6 which remains stationary, so that the second piston acquires a very high speed, of the order of several tens of m / s under the effect of the very high pressure of the compressed air arriving in the cylinder 3 via the flexible pipe 72 of small diameter. The air in the sealed chambers 343 and 344 is compressed in front of the piston head 31. When the front end 33 of the piston rod 32 strikes the bottom 65 of the hole 64 of the push rod 6, the force communicated by the second piston at rod 6 is several thousand Newtons. This force is all the greater when the stroke D1 is long and the mass of the second piston is low. By way of example, for a diameter of the head 31 and a mass of piston 31-32 of the order of 40 mm and 60 g, the communicated force is approximately 6450 N corresponding to a stroke D2 of 73 mm.

At the end of the stroke D1, the very high kinetic energy of the second piston 31-32 is almost completely communicated to the push rod 6, during the elastic shock of the end 33 of the piston rod 32 against the bottom 65 of the hole 64. The piston head 31 stops against the stopper 30 and returns relatively slowly back to the rest position against the stopper 36 under the effect of the elastic expansion of the air which has been compressed in the chamber before 344 and which again gradually fills the chamber 343 through the vents 345.

Following percussion by the piston rod 32, the push rod 6 is propelled very quickly forward over a distance D2 until its head 61 strikes the elastic washer 63 in the adapter support 4 intermediate between cylinders 2 and 3. During this forward propulsion, the insert 1 is pushed by the front end 68 of the push rod sliding in the bores 262 and 52 of the first piston rod and of the magazine and forced into hole T of part P to a depth equal to D2. The depth D2 is generally at least greater than the height of the insert 1 when the latter has no shoulder between upper 11 and lower portions 12, or is equal to the height of the lower portion 12 when the insert comprises a head 11 in the form of a base. In the case where the insert 1 is split, as shown in FIG. 1, the lower parts of the insert 1 shared by the slot 18 are substantially brought together by narrowing of the slot 18 and sensitive folding at the level of the groove 13; the subsequent introduction of a screw or other connecting element into the bore 17 of the insert 1 will widen the slot 18. In all cases, the grooves 14 and sharp teeth 15 penetrate into the material of the part P and thus block the insert in the hole T both in translation and in rotation.

This firm implantation of the insert 1 in the hole T allows the relatively low friction sliding of the clamp 66 in the axial hole 17 of the insert when the push rod 6 returns to its rest position under the restoring force exerted. backwards by the spring 62 against the rod head 61. The stress of the spring 62 is chosen so that it is sufficient to quickly disengage the clamp 66 from the implanted insert while not being too high so as to to prevent the bottom 65 of the hole 64 from hitting the end 33 of the piston rod 32 when the second piston recedes and thus the push rod 6 "bounces" so as to be propelled again towards the front of the device.

It should be noted that the washer 63 limiting the advance and propulsion stroke D2 of the push rod 6 is made of elastomer so as to absorb a large part of the kinetic energy of the push rod. The washer 63 is advantageously interchangeable so that the thickness of the washer 63 is chosen as a function of the penetration depth of the insert 1 in the hole T. In addition, as a function of the density of the material of the part P, the penetration force of the insert 1 into the hole T can be adjusted either by modifying the length of the stopper 30, or by modifying the length of the rod 32 of the second piston, or the depth of the hole 64 of the push rod 6 by means of suitable removable circular shells.

Furthermore, the magazine 5 and the clamp push rod 6 are interchangeable in order to adapt the diameter of the clamp 66 to the diameter of the bore 17 of the insert, and the diameter of the front end of the rod. pusher and bores 52 and 53 of the magazine 5 with the external diameter of the insert 1.

Other embodiments within the scope of the object of the invention can be envisaged.

The front end of the device can comprise at the front other means for retaining and grasping an insert injected into the conduit 53 than the lugs 54 and the clamp 66.

According to the embodiment shown in Figs. 7 to 9, the front end of the second branch of the loader 5a which has the bore 52a, and the front end 68a of the push rod 6a are modified relative to FIG. 3A.

The front end of the loader 5a also has three pins 54a embedded in three radial holes 55a of the loader and distributed axially. However, the lugs 54a never protrude inside the bore 52 and therefore do not hinder the passage of an injected insert. The lugs 54a serve to make a ring 541a integral with the front end of the charger. Thus, the pins pass through radial holes 542a of the ring 541a respectively aligned radially with the holes 55a. Shouldered and split heads of the lugs 54a are applied radially against the external periphery of the ring 541a by an external annular spring 56a. The spring is partially housed in the slots of the lug heads and surrounds the front end of the charger 50 in front of the cylinder 2a.

The internal bore of the ring 541a has three rectangular longitudinal grooves 543a equally distributed radially between them and also with the holes 541a, as shown in FIG. 8. The grooves 543a respectively receive flat longitudinal portions 673a of elastic metal strips 67a, one of which is shown in detail in FIG. 9. A strip 67a comes from a rectangular plate and successively comprises a short upper end 671a perpendicular to the axis Y′Y and having a length substantially equal to the thickness of the ring 541a, a right angle bend 672a, a long portion 673a parallel to the axis Y′Y and substantially equal to the height of the ring 541a and along the outer front end of the second branch of the loader, an elbow 674a applied at rest against a front chamfer of the loader body, and an inclined portion 675a projecting in front of the mouth of the bore 52a and preferably terminated by a hooked curvature 676a.

At rest as shown in Figs. 7 and 8, the curved ends 676a of the strips 67a are brought closer to the axis Y′Y of the bore 52a by a radial distance less than the external radius of an insert, so that the strips 67a stop an insert, like the lugs 54 shown in FIG. 4. When the loader 5a moves back, and particularly as soon as the inserted insert abuts against the end 68 of the push rod 6, or the end 68a of the push rod 6a, the ends 676a of the strips 67a slide against the periphery of the insert to substantially the upper portion 11 or the head 14 thereof. By virtue of the inherent bending at the lower ends 675a of the strips, these grip the insert and present it completely projecting and visible at the front of the magazine and of the push rod, in a manner analogous to FIG. 6.

It appears that according to the embodiment shown in Figs. 7 to 9, the elastic strips 67a both stop an insert injected into the loader when the latter has advanced relative to the body of the setting device and therefore has moved away from the front end of the push rod , and then grasp and hold the insert stopped at the front of the charger, when the charger has moved back to its rest position in the device body, and therefore has approached the front end of the charger.

For this embodiment, the push rod can be simply terminated by a smooth guide stud 66a having a diameter substantially less than the bore 17 of the insert, or it may not include a stud 66a (Fig. 7) or pliers 66 (Fig. 3A) when the insert does not have a central hole at least in the upper part 11. During the implantation of the insert, the ends hooks 676a of the strips 67a forming pads slide on the body of the push rod 6a.

According to other variants, the means for stopping an injected insert and the means for grasping a stopped insert according to FIG. 3A can be combined with those of FIG. 7. In other words, the lugs 54a can have retractable ends by the push rod 6a, and the stud 66a can be replaced by the stud 66.

At the rear cylinder of the inserting device, the cooperation between push rod and second piston head can be carried out according to FIG. 10.

Compared to Fig. 3B, the embodiment according to FIG. 10 is mainly characterized by a head 31a which is mounted to slide freely longitudinally along a cylindrical axis 32a. The stationary axis 32a replaces the movable rod of the second piston 32. A rear end 321a of the axis 32a is fixed to the center of the stopper 36a of the flanged cap 37a.

The axis 32a crosses the chamber 343a of the cylinder liner 34a and therefore substantially the front stopper 30a, like the rod 32 when it is at rest. However, the front end of the axis 32a has a relatively long stud 322a which slides into a complementary blind hole 64a made in an axial protuberance 641a behind the head 61a of the corresponding push rod 6a. The head 61a forms a collar between the solid body of the rod 6a which slides in the bore 262 of the first piston rod 26, and the protuberance 641a. This protuberance has a diameter equal to that of the axis 32a and is perfectly abutted thereon when the push rod 6a is at rest, abutting against the front face of the stopper 30a, under the action of the spring 62a, as shown in Fig. 10.

As also shown in FIG. 10, the bore 301a of the stopper 30a has a much larger diameter than that of the stopper 30, and is somewhat smaller than that of the push rod head 61a. This bore allows the passage of the cylindrical front portion 311a of the head 31a so that it reaches the rear face 65a of the head 61a.

By analogy with the piston head 31, the head 31a similar to a slide on the axis 32a is stationary during the first operating step relating to the loading of an insert, and performs a forward stroke then a reverse stroke with intermediate percussion of the rod 6a during the second operating step relating to the introduction of the loaded insert into the hole T of the part P. The percussion takes place between diametrical surfaces, such as the rear face 65a of the push rod head 61a and the front face 313a of the cylindrical portion 311a of the head 31a, which are much larger than those of the bottom 65 of the hole 64 in the push rod 6 and the front end 33 of the rod piston 32. The impact on the rod 6a is therefore better distributed, and greater forces can be communicated to the rod 6a. At the end of the front stroke of the head 31a, the rear base 312a of the head 31a slidably mounted in the cylinder liner 34a abuts against the rear face of the stopper 30a. Then the slide head 31a returns back to the rest position against the stopper 36a thanks to the expansion of the compressed air from chamber 344a to chamber 343a.

So that the long axis 32a is always in alignment with the rear protrusion 641a of the push rod 6a, the length of the stud 322a and the hole 64a is at least greater than the propulsion stroke D2 of the push rod 6a .

Claims (19)

1 - Automatic apparatus for fitting inserts (1) comprising an apparatus body (10, 2, 3, 4), an insert magazine (5) located at a front end (2) of the apparatus body and including a longitudinal duct (52) and a lateral insert injection duct (53) opening into the longitudinal duct through an orifice (57), retractable means (54; 67a) mounted at the front of the magazine (5) for stop an insert injected (1) in the longitudinal duct, and a push rod (6) slidable in the body of the device and in the longitudinal duct of the magazine, characterized in that the magazine (5) is mounted with longitudinal sliding in the front end (2) of the device body (10, 2, 3, 4), and in that the device comprises means (66; 67a) fixed to one of the front ends of the charger (5a) and push rod (6) for gripping a stopped insert (1) and means for moving the magazine (23-26, 25) to first move the magazine (5) away from an extremit é front (68) of the push rod (6) so that said orifice (57) is open in front of the front end of the push rod (6) for the passage of an injected insert (1) towards the longitudinal duct (52) and so that the injected insert is stopped by the means for stopping (54; 67a), and then to bring the charger (5) closer to the front end (68) of the push rod (6) so that said orifice (57) is closed by the front end of the push rod (6) , that the stopped insert is gripped by the means for gripping (66; 67a), and that the gripped insert (1) is completely outside the device in front of the front end (68) of the rod- pusher (6) and charger (5), the push rod (6) being stationary in the device body (10, 2, 3, 4) during the movements of the charger (5). 2 - Apparatus according to claim 1, characterized in that the means for stopping comprise several lugs (54) located in the same transverse plane at the front of the loader (5) and pushed radially into abutment in the longitudinal duct (52) of the charger under the action of an annular spring (56). 3 - Apparatus according to claim 1 or 2, characterized in that the means for stopping an injected insert and the means for gripping a stopped insert comprise several strips hoses (67a) fixed to the front of the loader (5a) and having portions (675a) projecting in front of the loader and converging towards the axis (Y′Y) of the longitudinal duct (52a). 4 - Apparatus according to claim 3, characterized in that the means for stopping and for grasping comprise a ring (541a) around the front end of the loader (5a), internal grooves (543a) for accommodating longitudinal portions therein (673a) lamellae, studs (54a) passing radially through the ring and the front end of the magazine, and an annular spring (56a) pushing said studs radially against the ring. 5 - Apparatus according to any one of claims 1 to 4 for which an insert (1) has a central hole (17), characterized in that the means for gripping comprise a stud (66) with a longitudinal slot (67) fixed at the front end (68) of the push rod (6), the stud having a diameter substantially equal to the diameter of the central hole (17) of the insert (1). 6 - Apparatus according to any one of claims 1 to 5 for which an insert (1) has a central hole (17), characterized in that the front end (67a) of the push rod (6a) offers a guide pin (66a) having a diameter less than the diameter of the central hole (17) of the insert (1). 7 - Apparatus according to any one of claims 1 to 6, characterized in that the means for moving the loader comprise a first piston (23-26) fixed to a rear end (51) of the loader (5) and slidable around the push rod (6), first single-acting pushing means (70, 21) for advancing the first piston so that the loader moves away from the front end of the push rod (6), and the first elastic means (25) for moving the first piston back so that the magazine approaches the front end of the push rod. 8 - Apparatus according to any one of claims 1 to 7, characterized in that the means for moving the charger comprise, at the front of the body of the apparatus, a rear chamber (21), a first piston (23 -26) having a rear head (23) slidable around the push rod (6) and fixed to the rear of the magazine (5), a longitudinal guide groove (20, 27) formed in the body of the device and in which the magazine (5), a spring (25) housed in the chamber (21) to move the first piston head (23) back, and a transverse partition (22, 24) which is located between the chamber (21) and the guide groove (20) and which is crossed by the push rod (6) and the first piston rod (26), said partition (22, 24) forming a rear stop for the magazine recoil stroke and a front stop of the advance stroke of the head of the first piston (23). 9 - Apparatus according to any one of claims 1 to 5, characterized in that in addition, it comprises, at the rear, means (31, 32; 31a) for striking and advancing the push rod (6 ) in order to implant the gripped insert (1) in a hole (T) of a part (P) having a diameter substantially less than the external diameter of the insert, and second elastic means (62) for drawing back the rod -pusher. 10 - Apparatus according to claim 9, characterized in that the means for striking and advancing comprise a second piston (31-32; 31a) which is driven by a forward and backward stroke in a second single-acting cylinder (3; 3a) and of which a portion (32; 311a) strikes the stationary push rod (6; 6a) substantially at the end of the advance stroke of the second piston, and of the third elastic means (343, 344) for move the second piston back (31-32; 31a) after it has struck the push rod (6; 6a). 11 - Apparatus according to claim 10, characterized in that in the push rod (6) and behind it is formed a longitudinal blind hole (64) having a length (D1) substantially less than the stroke in advance of the second piston (31, 32) and a bottom (65) to be struck by the front end (33) of the rod (32) of the second piston. 12 - Apparatus according to claim 10, characterized in that the second piston (31a) is mounted to slide freely along a stationary longitudinal axis (32a) in the second cylinder (3a) and has a front face (313a) to strike a rear face (65a) of the push rod (6a). 13 - Apparatus according to claim 12, characterized in that the rear face (65a) of the push rod (6a) has a protuberance (641a) cooperating slidingly with a front end (322a) of the axis (32a). 14 - Apparatus according to any one of claims 9 to 13, characterized in that the push rod (6) has a rear head (61) which is immobilized against a rear stop (30) by said second elastic means (62 ) during the movements of the loader (5), and which is pushed against a front stop (63) against said second elastic means (62) in response to percussion by the means for striking (31, 32; 31a). 15 - Apparatus according to claim 14, characterized in that said front stop (63) is interchangeable in order to select its thickness as a function of the implantation depth of the insert (1) in the part hole (T) and is preferably an elastomer washer surrounding a thin internal reinforcement ring (631). 16 - Apparatus according to claim 14 or 15, characterized in that said rear stop (30) is interchangeable and further limits the end of the advance of the means for striking (31, 32; 31a). 17 - Apparatus according to any one of claims 10 to 16, characterized in that the third elastic means consist of air which is compressed in a sealed chamber (343, 344) during the advance of the second piston (31-32; 31a) and the expansion of which in said chamber causes said second piston to recede. 18 - Apparatus according to any one of claims 1 to 17, characterized in that it comprises first means (7, 71, 76), preferably pneumatic, for simultaneously activating the means of displacement of the loader (23, 26 ) and means for injecting an insert into the lateral duct (53) of the charger (5). 19 - Apparatus according to claims 9 and 18, characterized in that it comprises second means (38, 39), preferably pneumatic, independent of the first means for activating (7, 71, 76) for activating the means for striking and advance the push rod (31, 32; 31a).

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