FR2650780A1 - Machine for silk screen printing - Google Patents

Abstract

This is a printing machine of the sort including, carried by bars 11 articulated by connecting rods 13 onto a bed 10, a screen support 15 and a squeegee support 16. According to the invention, and in combination, on the one hand, connecting rods 22 are provided which are articulated to the bars 11, being formed, for at least one of them, by the extension of a connecting rod 23, and to which there may be attached, in an articulated fashion, a first set of plates (flanges) 24 capable of receiving a squeegee support 16 when the squeegee does not have autonomous control and, on the other hand, the bars 11 themselves carry directly, with an articulation, a second set of plates (flanges) 24' capable of receiving another squeegee support when the squeegee has such a control. Application to silk screen printing machines.

Description

"Silk screen printing machine"
The present invention relates generally to silk screen printing machines, and it relates more particularly to those of these printing machines which comprise a frame, two parallel bars, which, connected to one the other, in rotation, by transverse uprights, are each respectively articulated, in deformable parallelogram, to connecting rods pivotally mounted on the frame, a screen support carried by said bars, and, also carried by said bars being disposed to the right of said screen support, a squeegee support.

 As we know, after each printing, that the screen is fixed relative to the object to be printed if the surface of the latter to be printed is a flat surface, or that it is movable relative to this object if the printing surface thereof is a cylindrical surface, it is necessary that this screen is the object of a vertical movement of clearance relative to the printed object.

 It is the role of the connecting rods supporting the bars carrying the screen support to ensure this vertical release movement.

 As is known, also, it is necessary, jointly, that the squeegee has a vertical release movement relative to the screen.

 On some machines, it is associated, to do this, with the squeegee, an autonomous control, and, for example, a pneumatic control.

 On other machines, the scraper release movement is ensured mechanically, these machines comprising rods, which are articulated to the bars, being formed, for at least one of them, by the extension of a connecting rod, and on which can be attached to articulation a set of flanges adapted to receive the support of the squeegee.

 Because one of these links is formed by the extension of a link, and that, consequently, it benefits from an upper lever arm, the flanges in question, and therefore the squeegee, are, as research, the object of a differential displacement compared to the screen.

 The object of the present invention is generally to allow one or the other of these two arrangements to be implemented, very simply, on request, and also leading to other advantages.

 More specifically, it relates to a silk screen printing machine of the kind comprising a frame, two parallel bars, which, connected to each other, in rotation, by transverse uprights, are each respectively articulated, in deformable parallelogram, to connecting rods pivotally mounted on the frame, a screen support carried by said bars, and, also carried by said bars being disposed in line with said screen support, a squeegee support, this printing machine being generally characterized in that, in combination, on the one hand, it comprises connecting rods which are articulated to the bars, being formed, for at least one of them, by the extension of a connecting rod, and on which a first set of flanges adapted to receive a squeegee support can be attached to the hinge when it is a squeegee without independent control, and, on the other hand, said bars p Orent themselves, directly, hinged, a second set of flanges adapted to receive a squeegee support when it is a squeegee with which there is associated such an autonomous control.

 Depending on the type of squeegee to be used, it suffices to attach the corresponding support to one and the other of the two sets of flanges thus provided according to the invention.

 The disassembly and corresponding assemblies are therefore particularly simple and easy to perform.

 If desired, the first set of flanges can also be permanently attached to the rods, which further reduces the disassembly operations to be performed.

 Preferably, and according to a development of the invention, the flanges of each of the two sets of flanges thus used comprise, staggered along their height, and in correspondence with one another, a plurality of holes suitable for allow to bring a squeegee support.

 By the simple choice of the holes to be used, it is thus advantageously possible to adapt the squeegee in height relative to the printing plane, that is, from one object to another, this printing plane is not the same, either that it is necessary to adjust the pressure of the squeegee on the screen as best as possible.

 These same holes also facilitate the substitution of one squeegee for another, especially when it is desirable to use a particular squeegee, and, for example, a tilting squeegee.

The characteristics and advantages of the invention will become apparent from the description which follows, by way of example, with reference to the appended schematic drawings in which
Figure 1 is, for a first type of squeegee, a perspective view of a printing machine according to the invention, from which were removed the screen and the squeegee
Figure 2 shows, on a larger scale, the detail of Figure 1 identified by an insert II in this figure 1
Figure 3 is, on a different scale, a partial view in longitudinal section of the printing machine according to the invention, along line III-III of Figure 2
Figure 4 is, on a smaller scale, a partial perspective view similar to that of Figure 2, for a second type of squeegee
Figure 5 is a partial perspective view similar to that of Figure 4, for an alternative embodiment of the invention.

 In Figure 1, we recognize a silk screen printing machine.

 This silk screen printing machine being well known in itself, and not belonging to the invention, it will not be described in all its details here.

 Only the elements necessary for understanding the invention will be described therein.

 It will therefore suffice to indicate that it comprises a frame 10, two parallel bars 11, which, connected to each other, in rotation, by transverse uprights 12, are, each respectively, articulated, in deformable parallelogram, at each due their ends, to connecting rods 13 pivotally mounted on the frame 10 around shafts 14 parallel to the bars 11, a screen support 15 carried by the bars 11, and, also carried by these bars 11, being disposed in line with the screen support 15, a squeegee support 16 or 16 '.

 A mechanical control 18, controlled by a motor 19, makes it possible to control back and forth, on the lower shaft 14, a drive unit 20.

 If the surface to be printed is flat, the screen support 15 is fixed, and the squeegee support 16, or 16 ′, is secured to the drive unit 20.

 If, on the contrary, the surface to be printed is cylindrical, the squeegee support 16, or 16 ′, is fixed, and the screen support 15 is wedged on the drive block 20.

 In synchronism with the movement of this drive unit 20, the mechanical control 18 also makes it possible to impart to the connecting rods 13 a pivoting movement around the shafts 14, which results, for the bars 11, and therefore, at least, for the screen support 15, the necessary release movement.

 In the embodiment shown, the screen support 15 is directly carried by the transverval uprights 12, which are in practice vertical.

 According to the invention, and in combination, on the one hand, there are provided rods 22, which are articulated to the bars 11, being formed, for at least one of them, in this case the rod 22 upper, by the extension of a connecting rod 23, and on which can be attached, articulated, a first set of two flanges 24, adapted to receive a squeegee support 16 when, as shown in Figures 1, 2, the corresponding squeegee does not have an independent control, and, on the other hand, the bars 11 themselves carry, directly, at articulation, a second set of flanges 24 'suitable for receiving a squeegee support 1,6' when, as shown in FIGS. 4 and 5, it is associated, with the corresponding squeegee, with an independent control 26.

 In practice, two flanges 24 are provided, and they frame the connecting rods 22, being connected to each other by axes 27 traversing these connecting rods 22 in rotation.

 In the embodiment shown, these flanges 24 have rounded ends.

 Anyway, they have, staggered along their height, on their front edge, and in correspondence with each other, a plurality of holes 28 adapted to allow to bring the squeegee support 16 corresponding.

 In the embodiment shown; and in a manner known per se, this squeegee support 16 comprises, in the form of a bracket, a block 29, by which it can be attached to the flanges 24, using screws 30, and a bar 31, which s extends transversely, horizontally, and on which is mounted, adjustable in position and / or in height, a stirrup 32 suitable for carrying the squeegee concerned.

 The flanges 24 ', which are also two in number, also frame the rods 22, but at a distance from the previous flanges 24.

 In the embodiment shown, their ends are straight.

 Whatever the case, they are brought together at mid-height by a spacer 33.

 In the embodiment shown, the latter is formed by a screw-nut assembly 34, with, disposed around the barrel of the screw, between the flanges 24 ', to abut the latter, a socket 35.

 Preferably, and as shown, when, as in this case, at least one bearing 36 is interposed between each link 22 and the corresponding bar 11, the flanges 24 'are each engaged, by a bore 37, on the outer cage of such a bearing 36, duly extended for this purpose, Figure 3.

 In practice, there are provided, at the ends of such a bearing 36, split elastic washers 39 suitable for its axial retention with respect to the corresponding rod 22, and, preferably, it is made so that the flanges 24 ', which are arranged in the immediate vicinity of these split elastic washers 39, are not pressed against them by the spacer 33.

 Thus, it is avoided that the flanges 24 ', which are preferably made of metal or light alloy, are damaged by the split elastic washers 39, which themselves are made of steel.

 Of course, instead of a single bearing 36, two bearings 36 can be provided between each link 22 and the corresponding bar 11, these bearings 36 being each respectively arranged at the ends of the corresponding bore of this link 22.

 Anyway, the flanges 24 'each have, staggered along their height, on their front edge, and in correspondence with one another, a plurality of holes 28', suitable for allowing 'add a squeegee support 16'.

 In the embodiment shown, this squeegee support 16 'comprises, in the form of a bracket, a block 29' ', by which it is adapted to be attached to the flanges 24', using screws 30, and a bar 31 ', which extends transversely to the horizontal, and on which is mounted, adjustable in position, the autonomous control 26. associated with the squeegee relates.

 For example, this autonomous control 26 is constituted by a pneumatic cylinder.

 The corresponding provisions not pertaining to the present invention, they will not be described here.

 If the squeegee to be used has no autonomous control, its squeegee support 16 is attached to the flanges 24, as shown in FIG. 2.

 Of course, the holes 28 of these flanges 24 then used are chosen according to the height to be given to the squeegee relative to the corresponding screen.

 If an independent control 26 is associated with the squeegee, the corresponding squeegee support 16 ′ is attached to the flanges 24 ′, FIGS. 4 and 5.

 .If desired, the flanges 24 are eliminated, FIG. 4.

 As a variant, they are permanently attached to the rods 22, FIG. 5.

 In this case, the block 29 ′ is shaped so as to be able to span the connecting rods 22.

 Of course, the present invention is not limited to the embodiments described and shown, but encompasses any variant.

Claims (5)

 1. A silk screen printing machine of the kind comprising, a frame (10), two parallel bars (11), which, connected to one another, in rotation by transverse uprights (12), are each respectively articulated, in deformable parallelogram, to connecting rods (13) pivotally mounted on the frame (10), a screen support (15) carried by said bars (11), and, also carried by said bars (11) , being arranged in line with said screen support (15), a squeegee support (16, 16 '), characterized in that, in combination, on the one hand, it comprises rods (22) which are articulated to the bars (11), being formed, for at least one of them, by the extension of a connecting rod (23), and on which a first set of flanges (24) suitable for receiving can be attached to articulation a squeegee support (16) in the case of a squeegee without independent control, and, on the other hand, said bars (11) carry themselves, directly, at articulation, a second set of flanges (24 ') suitable for receiving a squeegee support (16') when it is a squeegee with which there is associated such an autonomous control (26).  2. Printing machine according to claim 1, characterized in that the flanges (24, 24 ') of each of the sets of flanges have, staggered along their height, and in correspondence with one another, a a plurality of holes (28, 28 ') adapted to allow the attachment of a squeegee support (16, 16').  3. Printing machine according to any one of claims 1, 2, characterized in that the flanges (24 ') of the second set surround the rods (22) and are joined to each other by a spacer ( 33).  4. Printing machine according to claim 3, characterized in that, a bearing (36), at least, being interposed between each link (22) and the bar (11) corresponding, the flanges (24 ') of the second set are each engaged, by a bore (37), on the outer cage of such a bearing (36), duly extended for this purpose.  5. Printing machine according to any one of claims 1 to 4, characterized in that the first set of flanges (24) is permanently attached to the rods (22).