PADLOCK TYPE MARKING SEAL AND APPLICATOR FOR APPLYING PADLOCK TYPE MARKING SEALS

Abstract: A padlock type marking seal having a receiving body (2) with internal locking teeth (4) to receive the tip (9) of a loop of the seal that is integral with the body, and there being a marking tab (6) also integral with the body (1). In order to improve seal application, to ensure autopenetration into the material to be marked (e.g. meat), the tip is sharpened and there is a stop (11) on the loop, adjacent to and behind the tip so as to allow an applicator device to force the sharpened point to penetrate the material to be marked. The loop of the seal has a reduced thickness region defining a pivot point (8) with respect to the body, and the part (7) of the loop between the first end and the sharpened tip is substantially in the form of the arc of a circle. A reception cavity (3) in the body of the seal has an axis substantially tangential to the arc when the loop is pivoted about the pivot point, until its tip begins to enter said cavity. The applicator according to the invention is in the form of a pistol and is adapted to receive comb of seals. The applicator is operated pneumatically to: apply seals without the applicator element (39) having to penetrate the material to be marked; feed the next seal to the reception and application station (25); and cut the links (12) with the following seal before its application. The pistol is fired by a trigger and the operating sequence is controlled and effected by a remote control unit (15) comprising electronic control circuits (44) and pneumatic valves (16).

Description: Title: "Padlock type marking seal and applicator for applying padlock type marking seals" Technical field The present invention relates to padlock type mark- ing seals which are used to mark any type of material capable of being pierced by the tip of the seal lock. For example, cloth, live fish, cattle (through the ear), meat and the like may be marked using this type of seal. Background art There are two principal disadvantages encountered when using the seals and applicators of the present state of the art: Firstly, it is difficult to close the seals using mechanical applicators, due to the fact that there is normally only one pivot or fold point of the "loop" of the padlock, and the locking tip of the "loop" must enter the locking capsule in the body of the "padlock" in a substantially linear manner. The shape of the seals known in the state of the art is not very well adapted to operate in this way and there is a tend- ency, upon application of the seal, for it not to close prop¬ erly. In addition to this, the marking operation becomes slow; and Secondly, it is normally a needle portion of an applicator that penetrates the material to be marked, drawing the tip of the "loop" with it. This means that the applicator imposes design requirements which are difficult to comply with when aiming for simplicity of operation. As a result of this, mechanical applicators, as a rule, are not practical. In the majority of cases they can only be used for application of a single seal, not being provided with means for carrying a num¬ ber of seals, so that multiple application of the seals at an accelerated rate can not be carried out. Object of the invention The principal objects of the present invention are to provide a padlock type marking seal which is adapted to be easily applied and also to provide a marking seal applicator that is practical, fast and, in the preferred embodiment, ca¬ pable of carrying "combs" of seals that can be applied in se- guence. Summary of the invention According to a first aspect of the present invention a padlock type marking seal comprising a body defining a cav¬ ity having an internal locking formation, a loop having a first end integral with the body and a second end in the form of a tip formed to cooperate with the internal locking forma¬ tion of the cavity, the loop being flexible so as to permit said tip to enter the cavity and to become locked in said for¬ mation, and a marking tab integral with the body, the seal be- ing characterised in that: the tip of the loop is sharpened so as to be capable of penetrating the material to be marked; there is a stop on the loop, adjacent to and behind the sharpened tip, to allow an applicator device to force the sharpened tip to penetrate the material to be marked; the first end of the loop is connected to the body by a region of reduced thickness to define a pivot point; and the part of the loop between the first end and the sharpened tip is substantially in the form of an arc of a cir- cle, the cavity having an axis substantially tangential to said arc when the loop is pivoted about said pivot point until its tip begins to enter said cavity. Preferably, said arc is substantially semicircular. In the preferred embodiment of the present in- vention, the sharpened tip is in the form of a head connected to the rest of the loop by a neck, there being - in order to reinforce the tip and thereby prevent it from flexing as it penetrates the material to be marked - a reinforcement in the form of a connecting rib in the vicinity of the neck. The advantage of the seal of the present invention lies in the fact that, when the sharpened tip of the seal is placed against the material to be marked, pivoting of the loop causes the tip to enter the surface of the material almost rectilinearly, penetrating and then turning inside the mate- rial, in a way similar to a curved suture needle, finally to exit from the same surface that it went into and then directly to enter the cavity of the seal to cooperate with the locking formation. As in known seals, the locking formation is provided advantageously with one or more - normally three - internal teeth in said cavity. In this way, the reinforcement rib on the neck, between the sharpened tip and the remainder of the loop, can enter the space between two of these internal lock¬ ing teeth in the cavity of the seal. Apart from this, the stop behind the sharpened tip of the loop allows an applicator device to be used, the for¬ ward point of which does not need to effect penetration of the material to be marked, simply following the sharpened tip of the seal, which is itself used to effect penetration. According to a second aspect of the present in¬ vention, a marking seal applicator, for applying padlock type marking seals described above, comprises: a seal application and reception station; a feed guide for feeding a series of marking seals towards said reception and application station, a region of the reception and application station being open to the feed guide so as to enable a marking seal to pass from the guide into a reception and application position within said recep¬ tion and application station; a seal applicator device mounted at said reception and application station for rotation about a pivot point and adjusted to adapt itself automatically to the shape of the loop of a seal located in the reception and application sta- tion, with the sharpened tip of the loop of the seal directed away from the applicator device, the applicator device cooper¬ ating with the loop so as to move together with the applicator when it is rotated about the pivot point; a movable stop, displaceable between an open posi- tion, spaced from the reception and application station, and a seal application position in which the movable stop locates in said open region to align and support that portion of the seal defining said locking cavity; a first actuator, associated with the feed guide, for advancing the seals incrementally along the guide towards the reception and application station; a second actuator, associated with said movable stop, for displacing it between said open and seal application positions; and a third actuator, associated with said applicator device, for imparting rotational motion thereto, between an open seal position and a closed seal position, and for return¬ ing said applicator device to said open seal position. Preferably the first, second and third actuators comprise respective first, second and third pnuematic cylin¬ ders with return springs. The applicator may also include a cutting mechanism, adjacent the open region of the reception and application station, for cutting weakened links between adjacent seals in said series, the cutting mechanism being as- sociated with the second actuator so as to effect cutting si¬ multaneously with displacement of said movable stop to the seal application position. In the preferred embodiment, the applicator is in the form of a pistol with a trigger for starting an operating sequence of the actuators. There is also a remote control unit including pneumatic valves for controlling the application of pneumatic pressure to said cylinders and an electronic circuit programmed to open and close the valves according to the actuator operation sequence, the electronic circuit being ac- tivated by the trigger of the pistol. This sequence of oper¬ ations occurs as follows: a) the third actuator rotates the applicator device from its open seal position into the closed seal position and soon after back to the open seal position; b) the second actuator displaces the movable stop to said open position; c) the first actuator acts to impel the seals in the feed guide incrementally towards the reception and application station; and d) the second actuator displaces the movable stop back to its seal application position. The applicator pistol, according to the preferred embodiment of this aspect of the invention, allows rapid ap- plication of marking seals in series by pulling the trigger. Brief description of the drawings The present invention will now be described in greater detail, by way of example, with reference to the ac¬ companying drawings in which: Figure 1 is a plan view of a marking seal according to a first aspect of the present invention; Figure 2 is a lateral view of the seal shown in fig¬ ure 1, looking in the direction of the arrow, S; Figure 3 is a plan view of a comb of marking seals for use in the applicator shown in Figures 4 to 6; Figure 4 is a plan view of a marking seal applicator according to the preferred embodiment of a second aspect of the invention, one half of the seal applicator having been re¬ moved to allow the interior of the applicator to be seen and showing a comb of seals similar to that illustrated in Figure 3 with a first seal in position ready for application; Figure 5 is a longitudinal central cross sectional view of a pneumatic cylinder used to advance the seals in the applicator of Figure 4, as well as of a pneumatic cylinder which actuates cutting pins and advances a movable stop to support the seals at the time of application; Figure 6 is a longitudinal central cross sectional view of a seal actuator element, including a pneumatic cylin¬ der for operating the actuator element; and Figure 7 is a graph showing the sequence of oper¬ ations of the actuators and respective pneumatic cylinders of the applicator shown in Figures 4 and 6. Detailed description of the invention With reference to figures 1 and 2 of the drawings, a padlock type marking seal 1 comprises a body 2 defining a cav¬ ity 3 containing a locking formation in the form of three internal teeth 4. A connection 5 joins a rectangular marking tab 6 to the body. A loop 7 of seal 1, of transverse circular cross- section, is joined to the body at a first end by a region of smaller thickness that defines a folding or pivoting area 8 and comprises a substantially semicircular portion followed by a sharpened tip in the form of a head 9 having a neck which is joined to the rest of loop 7. With the object of ensuring that sharpened tip 9 does not flex, i.e. deflect, on penetrating the material to be marked, there is a rib 10 in the neck re- gion. When the seal is closed, sharpened tip or head 9 en¬ ters cavity 3, the head catching behind locking teeth 4 and becoming locked, thereby defining a closed configuration of the seal. It should be observed that in this closed position rib 10 fits between two of the three locking teeth 4. Slightly behind sharpened tip 9, at the end of the semicircular portion, there is a stop 11 in the shape of a barb to allow an applicator device to force sharpened tip 9 through the material to be marked, without an element of the device itself having to be sharpened in order to carry out the penetrating operation. Figure 3 shows a "comb" of seals 1, identical to the seal shown in figures 1 and 2 with the exception that respec¬ tive marking tabs 6 are joined to each other by two weakened points 12. A comb of seals such as that illustrated in figure 3 can be used with the applicator illustrated in figures 4 to 6. Referring now to figures 4 to 6, an applicator ac¬ cording to a preferred embodiment of the second aspect of the present invention comprises a pistol 13 having a trigger 14 and a programmed control unit 15 having pneumatic valves 16a, 16b and 16c. Pistol 13 comprises a pistol mechanism housed in a chassis having two halves 17 and 17' joined together by screws. The pistol mechanism comprises a seal feed guide 18, a feed actuator 19, a movable stop 20, cutting pins 21 (figure 5) to sever weakened points 12 between adjacent seals (see figure 3), an actuator 22 for movable stop 20 and cutting pins 21, a seal applicator device 23 and an actuator 24 thereof. Seal feed guide 18 receives the comb of seals 1 (figure 3), as illustrated, so that the seals can be fed to- wards a reception and application station 25. Feeding is car¬ ried out in incremental steps by means of feed actuator 19 which comprises a first pneumatic cylinder 26 including a pis¬ ton 27 having a feed arm 28 that enters between marking tabs 6 of the upper two seals on the comb, a yieldable ratchet 28a that enters between the second and third seals on the comb to prevent the seals from dropping back after feeding, and a re¬ turn spring 29 for piston 27. Pneumatic cylinder 26 is con¬ nected by a tube 30 to remote control unit 15 and more specifically to pneumatic valve 16a. Movable stop 20 is integral with a plate 31, fixed to the end of the rod of a piston 32 of a second pneumatic cylinder 33 which forms actuator 22. Cutting pins 21 also project from plate 31. Springs 34 positioned between plate 31 and cylinder 33 laterally separate movable stop 20 from recep- tion and application station 25 and cutting pins 21 from their cutting position. Cylinder 33 is connected by a tube 35 to pneumatic valve 16b in remote control unit 15 and, as will be described later, is normally subject to pneumatic pressure in order to keep movable stop 20 in the position illustrated. In such a position movable stop 20 obstructs the base of recep¬ tion and application station 25 with the body 2 of the first seal 1 supported therein and ready for application. Movable stop 20 also restricts reception and application station 25 both laterally and in its forward region so as to ensure that the seal will not move either laterally or forwards during ap¬ plication. Seal applicator device 23 (figure 6) comprises a pair of parallel bars 23* pivotally linked at first ends to a piston rod 36 of a third pneumatic cylinder 37 which forms actuator 24. Second ends of bars 23' are pivotally linked at two points 38 (laterally separated from each other) to a metal applicator element or cradle 39 in the form of an arc, the free end of which is pivoted about points 40, fixed with re- spect to chassis 17, 17" of the pistol. Cradle 39, having an internal surface that is semicircular in cross-section, re¬ ceives loop 7 of seal 1 and the upper or forward point of the cradle abuts the rear surface of barb shaped stop 11 on the seal. The distance between fixed points 40 and the axis of cavity 3 of seal 1 in the reception and application station is substantially the same as the diameter of the semicircle de¬ scribed by loop 7 of the seal. Thus, with a seal fed into reception and application station 25 as illustrated in figure 1, applying a pulse of compressed air to cylinder 37, supplied by pneumatic valve 16c and a tube 41, advances piston 36 against a return spring 42 causing bars 23' to move forward and rotate cradle 39 about a pivot axis corresponding to the line between fixed points 40. Such movement forces loop 7 of the seal in the reception and application station to pivot about its fold region 8, until tip 9 of the seal enters and becomes locked in cavity 3. It should be noted that cradle 39 ensures the alignment of loop 7 with cavity 3 of the seal during the closing operation, the position of body 2 of the seal being determined by movable stop 20. Operation of the marking seal applicator pistol is started by trigger 14 which is connected by an electrical con¬ nection 43 to an electronic circuit board 44 in programmed re¬ mote control unit 15. On pulling the trigger, circuit board 44 activates pneumatic valves 16a, 16b and 16c (these being con¬ nected to a supply of compressed air, not shown), according to the sequence of operations shown in figure 7, which are as follows: a) providing a pulse of compressed air from pneu- matic valve 16c to third pneumatic cylinder 37 - as described above - causing application (closing) of seal 1, imeadiately after which valve 16c is closed and spring 42 returns applicator device 23 to its original, open seal, position; b) closing second pneumatic valve 16b, to cut off the supply of pressure to second cylinder 33 of actuator 22 and thus allow springs 34 to move movable stop 20 and cutting pins 21 away from reception and application station 25, thereby leaving the lower part of station 25 free and open; c) applying a pulse of compressed air, from first pneumatic valve 16a, to first feed cylinder 26 which, by means of piston 27 and arm 28, advances the next seal 1 in feed guide 18 into position within reception and application sta¬ tion 25. After this, return spring 29 returns both piston 27 and arm 28 to their initial positions ready for the next cycle to commence whilst ratchet 28a ensures that the seals do not move back down feed guide 18; and d) once again opening second pneumatic valve 16b thereby pressurizing second cylinder 33 and thus returning movable stop 20 back to its initial position. At the same time, cutting pins 21 return to their cutting positions thereby cutting weakened points 12 between the seal in recep¬ tion and application station 25 and the adjacent seal which is still in feed guide 18. During use, immeadiately after applying the seal and termination of step b) above, the pistol is moved away manu¬ ally from the material being marked (a natural movement at this stage of the operation) and the seal, together with its marking tab 6, automatically leave the pistol permitting the sequence to be continued with steps c) and d) . It should be noted that the free spaces between parallel bars 23' of applicator device 23 and between fixed rotation points 40 al¬ low the unobstructed removal of the seal. On termination of the sequence a) to d) the pistol is already newly "armed" with the next seal in position for application. It will be obvious that the marking seal applicator pistol described above, with reference to the attached drawings, permits the rapid application in series of as many seals as there are in the comb of seals carried in the pistol. The operation is extremely easy, without requiring physical force, and the application is clean and reliable, thanks to the fact that applicator device 23 is not forced manually to penetrate the material to be marked (remaining be- hind sharpened tip 9 of the seal) and that tip 9 of the seal enters substantially rectilinearly into cavity 3. This is of utmost importance when marking comestible products, partic¬ ularly meat. Note that, for this reason, the front end or tip of cradle 39, of applicator device 23, is champhered so as not to not create any influence on the material to be marked as it follows sharpened tip 9 of the seal. The present invention is not limited to the pre¬ ferred embodiments illustrated in the drawings. Many vari¬ ations will be evident to those skilled in the art and the scope of the invention should therefore be limited only by the terms and interpretation of the following claims.

Claims: CLAIMS 1. Padlock type marking seal comprising a body de¬ fining a cavity having an internal locking formation, a loop having a first end integral with the body and a second end in the form of a tip formed to cooperate with the internal lock¬ ing formation of the cavity, the loop being flexible so as to permit said tip to enter the cavity and to become locked in said formation, and a marking tab integral with the body, characterised in that: the tip of the loop is sharpened so as to be capable of penetrating the material to be marked; there is a stop on the loop, adjacent to and behind the sharpened tip, to allow an applicator device to force the sharpened tip to penetrate the material to be marked; the first end of the loop is connected to the body by a region of reduced thickness to define a pivot point; and the part of the loop between the first end and the sharpened tip is substantially in the form of an arc of a cir¬ cle, the cavity having an axis substantially tangential to said arc when the loop is pivoted about said pivot point until its tip begins to enter said cavity. 2. Marking seal according to claim 1, characterised in that said arc is substantially semicircular. 3. Marking seal according to claim 1 or 2, characterised in that said stop is in the form of a barb. 4. Marking seal according to claim 1, 2 or 3, characterised in that the sharpened tip is in the form of a head connected to the rest of the loop by a neck, there being a reinforcement in the form of a connecting rib in the vicin- ity of the neck. 5. Marking seal applicator for applying padlock type marking seals in which the tip of the loop of the seal is sharpened so as to penetrate the material to be marked and, upon exiting the other side of the material, to enter into a locking cavity of the seal, characterised by comprising: a seal application and reception station; a feed guide for feeding a series of marking seals towards said reception and application station, a region of the reception and application station being open to the feed guide so as to enable a marking seal to pass from the guide into a reception and application position within said recep¬ tion and application station; a seal applicator device mounted at said reception and application station for rotation about a pivot point and adjusted to adapt itself automatically to the shape of the loop of a seal located in the reception and application sta¬ tion, with the sharpened tip of the loop of the seal directed away from the applicator device, the applicator device cooper¬ ating with the loop so as to move together with the applicator when it is rotated about the pivot point; a movable stop, displaceable between an open posi¬ tion, spaced from the reception and application station, and a seal application position in which the movable stop locates in said open region to align and support that portion of the seal defining said locking cavity; a first actuator, associated with the feed guide, for advancing the seals incrementally along the guide towards the reception and application station; a second actuator, associated with said movable stop, for displacing it between said open and seal application positions; and a third actuator, associated with said applicator device, for imparting rotational motion thereto, between an open seal position and a closed seal position, and for return¬ ing said applicator device to said open seal position. 6. Marking seal applicator according to claim 5, characterised in that said first, second and third actuators comprise respective first, second and third pnuematic cylin¬ ders with return springs. 7. Marking seal applicator device according to claim 5 or 6, characterised by further comprising a cutting mech¬ anism, adjacent said open region of the reception and applica¬ tion station, for cutting weakened links between adjacent seals in said series, the cutting mechanism being associated with the second actuator so as to effect cutting simultane- ously with displacement of said movable stop to the seal ap¬ plication position. 8. Marking seal applicator according to claim 6 or 7, characterised by being in the form of a pistol with a trig- ger for starting an operating sequence of said actuators. 9. Marking seal applicator according to claim 8, characterised by further comprising a remote control unit in¬ cluding pneumatic valves for controlling the application of pneumatic pressure to said cylinders and an electronic circuit programmed to open and close said valves according to said actuator operation sequence, the electronic circuit being ac¬ tivated by the trigger of the pistol. 10. Marking seal applicator according to claim 9, characterised in that upon pulling said trigger said operating sequence occurs as follows: a) the third actuator rotates the applicator device from its open seal position into the closed seal position and soon after back to the open seal position; b) the second actuator displaces the movable stop to said open position; c) the first actuator acts to impel the seals in the feed guide incrementally towards the reception and application station; and d) the second actuator displaces the movable stop back to its seal application position.

Inventors: DE LIMA CASTRO NETTO EDUARDO, DE LIMA CASTRO NETTO, EDUARDO
Applicants: ELC PROD SEGURANCA IND, LIMA CASTRO NETTO E DE, DE LIMA CASTRO NETTO, EDUARDO, ELC PRODUTOS DE SEGURANCA INDUSTRIA E COMERCIO LTD
Application year: 1996
Main classification: G09F3
IPC codes: A01K11, B65C7, G09F3