FR2802463A1 - Press to manufacture friction lining for gearbox or braking system comprises superior plate being fixed, inferior plate moved by piston and the intermediate plates linked by three with maximum relative distance between them - Google Patents

Abstract

Press (20) comprises multiple plates sliding along columns (26), the superior plate being fixed (PSF) and the inferior (PIM) moved by a piston (28,30). Each plate (PRi) is associated to the higher (PHi) and lower plates (PBi) by a number of command bars (42) attached to a command block (44) so that the distance between each plate of the group is limited.

Description

The present invention relates to a multi-plate press. The invention relates more particularly to a multi-plate press used in the field of manufacturing friction or friction linings used in transmissions or in braking devices of motor vehicles.

Many methods of manufacturing these friction linings call for one or more molding and / or baking stages during which the linings are received between lower and upper molds to be pressed and heated. In order to carry out the stages of die-casting in large series and at a reduced cost, use is made of a multi-plate press comprising a stack of plates among which a fixed upper reaction plate and a movable lower plate for clamping under the action of one or more cylinders for pressurizing the stacking trays, and comprising a series of intermediate trays which are mounted to slide freely along vertical guide supports. As will be explained hereinafter with reference to the detailed description of a press according to the teachings of the invention, it comprises numerous pieces of equipment making it possible in particular, during the molding and baking process, to determine the relative vertical position of the plates when the press is in the open position (called full opening), to determine the relative vertical position of the plates when the press is in the degassing position (called intermediate or partial opening) of the molds, to compensate for the weight of the plates so as to guarantee a tightening force of uniform value for all stacked molds, and cause forced opening of the tools by simple means. The invention aims in particular to propose means making it possible to reduce the size of the plates in the horizontal plane and to simplify the design of the press by reducing the cost, the overall dimensions and by facilitating the assembly and disassembly of the plates.

To this end, the invention provides a press with multiple plates of the type mentioned above, characterized in that it comprises at least one pair of intermediate plates among which a reference lower plate is provided with a device which associates the two plates with it. high and low which are adjacent to it, which is linked in vertical translation to this reference plate and which determines the maximum position upwards, respectively downwards, of the associated high plate, respectively low, relative to the reference plate, and in that the high plate associated with the reference plate of the higher pair of intermediate plates is immobilized in vertical translation downwards when the press is opened.

According to other characteristics of the invention - said high plate associated with the reference plate the highest pair of intermediate plates is immediately adjacent to the fixed upper reaction plate; - press comprises at least two successive pairs of intermediate plates, and in that the low plate adjacent to the reference plate of the upper pair is the high plate adjacent to the reference plate of the lower pair; - mobile clamping plate is the plate associated with the reference plate of the lowest pair of intermediate plates; - association device is a C-shaped element whose vertical branch is fixed along a lateral edge of the reference plate and whose upper horizontal branch, respectively lower, extends opposite a portion of the upper face associated upper tray, respectively of the lower face of the associated tray; - Associating device is a vertical rod whose central section fixed to the reference plate and whose high end section, respectively bottom, is received by sliding through a hole formed in the top plate, respectively bottom, associated provided with its free end of a radial flange which extends opposite a portion of the upper face of the associated upper plate, respectively of the lower face of the associated lower plate; - Each tray is a rectangular tray, that each two parallel and opposite lateral edges of the reference tray is provided with two association devices spaced transversely; each intermediate plate carries a half-mold on each of its opposite faces; each tray is provided, along one of its edges, with a horizontal bar which is guided in vertical sliding by means of pads carried by vertical structural elements in the form of columns; each tray carries a vertical control bar which extends downward and which comprises a radial degassing flange on which acts a degassing plate actuated by degassing cylinders.

Other characteristics and advantages of the invention will appear on reading the detailed description which follows, for the understanding of which reference will be made to the appended drawings in which FIG. 1 is a side view in elevation. multiple plates in accordance with the teachings of the invention and comprising three pairs of stacked intermediate plates PRi, PHi; Figure 2 is a sectional view through an intermediate horizontal plane passing through line 2-2 of Figure 1; Figure 3 is a schematic perspective view on a larger scale illustrating a first embodiment of the association means between plates in the form of C-stud; Figure 4 is a simplified schematic view illustrating the stacking of the plates of the press of Figure 1 are illustrated in the closed position of the press; Figure 5 is a view similar to that of Figure 4 in which the plates are illustrated in the open position of the press; Figures 6, 7 and 8 are views similar to those of Figures 3 to 5 which show a second embodiment of the association means between plates in the form of shouldered rods; - Figure 9 is a top view of an intermediate plate intended to be associated with its adjacent plates by the shouldered rods illustrated in Figures 6 to 8; - Figure 10 is a large-scale diagram showing the means the press shown in Figure 1 for the compensation of the weight of the plates and the degassing of the molds, on which these means are shown during a step of mounting compensation rods weight ; and - Figure 11 is a view similar to that of Figure 10 on which is shown the degassing step of the molds.

In the description which follows, identical, similar or analogous components will be designated by the same numbers and reference letters.

has shown in Figures 1 and 2 a multiple plate press having a lower frame 22 and an upper frame 24 which are connected together by vertical structural elements in general column form.

In addition to their structural functions, the columns 26 are shaped to guide the sliding of the press plates 20. press 20 comprises a lower main tightening cylinder 28 whose body 30 rests on the lower frame 22 and whose piston 32, sliding vertically, bears on its upper face a movable lower plate PIM which moves vertically in two directions with piston 32 to tighten vertically, or release the clamping force, by reaction against the upper frame 24 under the lower face of which fixed a fixed upper plate PSF, cylinder 28 a thus the function of allowing vertical axial clamping set of plates comprising the movable lower plate and the fixed upper plate PSF, as well as a set of intermediate plates.

In the application illustrated in the figures, the press 20 has the function of allowing the molding and the cooking under pressure of friction linings (not shown) which are received in two-part molds each comprising an upper mold MS and a lower mold MID. Thus, the movable lower plate PIM carries on its upper face a lower mold MI and the fixed upper plate PSF carries on its lower face an upper mold MS.

The other plates of the press, within the meaning of the invention, are in even number and are constituted by pairs of intermediate plates in each of which there is a reference plate PRi and an upper plate PHi, where high plate, which is immediately adjacent.

In the example illustrated in the figures, the press 20 comprises six intermediate plates in the form of three pairs of plates - PH1, PR2-PH2, -PH3 (see FIGS. 3 et seq.) Which are arranged between the movable lower plate PIM and the PSF fixed upper plate.

Each intermediate plate is provided on its upper and lower opposite faces with a lower mold MI and an upper mold MS respectively, the assembly of the plates of the press 20 thus making it possible to produce seven superimposed molds.

The movable lower plate PIM is provided with a lower mold on its upper face and the fixed upper plate PSF is provided with upper mold on its lower face.

When press 20 is used for a pressure cooking step, some of the plates can of course be heated. All trays are of generally rectangular shape, each of them is delimited by two parallel lateral edges 34 by two parallel transverse edges 36 (see FIG. 2).

As can be seen in Figure 2, each intermediate plate is provided, along its two transverse edges 36 with a horizontal bar 38 each of which extends laterally beyond a lateral edge and a column 26 of so that its free end 40 carries a vertical control bar 42 which extends downwards in the direction of the control block 44 shown in FIG. 1.

As can be seen in FIG. 1, the different bars 42 are offset laterally and are aligned in groups of six in the same vertical plane. They connect the horizontal bars 38 to the control block 44. As can be seen in FIG. 2, the horizontal bars 38 are also guided in vertical sliding along the columns 26 by means of guide pads 41 fixed on the columns 26.

This guide arrangement is particularly advantageous compared to the prior art because it makes it possible to reduce the longitudinal space requirement of the trays and the cost of the trays by reducing the corresponding machining operations.

According to the first embodiment illustrated in FIGS. 1 to 5, the various intermediate plates are associated by crampon-shaped devices Ci carried by the intermediate reference plates More precisely, each reference plate PRi carries along each of its two lateral edges 34 two pairs of crampons Ci offset transversely and arranged in the vicinity of the corresponding angles of the intermediate reference plate PRi.

Each crampon Ci has the general shape of C and, as can be seen in particular in detail in FIG. 3, it comprises a vertical central branch 48 and two upper and lower horizontal branches in the form of horizontal plates.

For the attachment of each crampon Ci on a lateral edge of a reference plate PRi, and in order to link it in vertical translation thereto, vertical branch 48 has a notch 54 in which is received lateral edge 24 of the corresponding reference plate , the clamp being fixed on this edge by a screw (not shown).

As can be seen in particular in FIGS. 4 and the dimensions of each crampon Ci are such that the plate PBi immediately adjacent to the reference plate PRi received vertically with clearance between the lower horizontal branch of the crampon Ci and the reference plate PRi and are such that PHi high plate immediately adjacent to the reference plate received vertically with clearance between the upper horizontal branch of the crampon and the PRi reference plate.

As can be seen in Figures 4 and 5, due to the stacking of the nested mounting plates of the pairs of intermediate plates of the studs, the bottom plate of a pair of intermediate plates constitutes the top plate of the pair of intermediate plates located immediately below.

Thus, for example, the high plateau PH1 associated with crampons to the lowest reference plateau PR1 constitutes the plateau associated by crampons C2 with the reference plateau PR2 following above.

note that the low plate PB1 associated by crampons C1 with the reference plate PR1 of the pair of intermediate lower plates consists of the movable lower plate PIM.

In the example illustrated in the figures, the most upper intermediate plate PH3 is the plate immediately adjacent to the fixed upper plate PSF and the press has a fixed stop B extends between intermediate plates PR3 and PH3, below the lower face of the high plate PH3 with which it is capable of cooperating to determine the low vertical position of maximum opening of the high intermediate plate PH3 when the press is opened In the position shown in FIG. 4, that is to say when the press is closed and the molds are under pressure, we see the relative vertical position of the different plates, and in particular intermediate plates, is independent of the crampons Ci and 'it does not depend on the thicknesses of the molds clamped in two parts MS. When the press 20 is opened, that is to say when the piston 32 of the jack descends by releasing the pressure force applied to the stacking of the plates and by vertically moving the movable lower plate PIM, the intermediate plates are free to descend vertically by gravity under the effect of their own weight.

During this overall downward movement, the plate PH3 comes, by lower face 60, to bear against the fixed stop B.

The maximum opening position of the most upper mold constituted by the two parts of molds carried respectively by the fixed upper plate PSF and by the plate PH3 is thus determined precisely.

The maximum opening position of the other molds, that is to say the relative vertical position of the other intermediate plates and of the movable lower plate PIM, is determined indirectly by the successive intervention of the crampons Ci.

Indeed, and as can be seen in FIG. 5, the upper branches of the spikes C3 come into vertical abutment against the upper face of the plate PH3 thereby determining the precise position of the reference plate PR3 and its associated bottom plate PB3 which is also the high plate PH2 associated with the reference plate PR2 thereby determining, by means of the studs C2, the precise vertical position of the intermediate reference plate PR2 and its associated plate PB2, etc.

All maximum mold opening positions are precisely and unequivocally determined.

made preliminary operations of molding and cooking under a significant tightening force, it could occur phenomena of sticking molds and the crampons Ci then intervene to force the opening of the molds, the crampons C1 associated with the mobile lower plate PIM then intervening first to request plate PH1 which is also low plate PB2 which requests crampons and so on. When closing movement again press, the dimensions crampons Ci allow tightening the stacking of the plates without 'they do not interfere.

According to the second embodiment of the means of association of the intermediate plates shown in FIGS. 6 to 9, crampons Ci are replaced by rods Ti.

Each association rod Ti is a shouldered rod comprising, in the middle of the central vertical section, two external radial flanges delimiting between them the notch 54 and comprising at its upper and lower free ends two upper 50 and lower 52 flanges equivalent to the horizontal branches 50 and 52 of the crampons Ci.

Each intermediate plate has holes 62 arranged by two series of four holes, each of which is traversed by a part of the body of a rod Ti. The mode of association of the intermediate plates and of the fixed upper PSF and mobile lower PIM plates is identical to that described previously with reference to the crampons Ci.

There is shown schematically, but in more detail, in Figures 10 and 11 the hydraulic control unit 44 which acts on the vertical control rods 42. The block 44 comprises a hydraulic housing 66 outside of which protrude six rods jacks 68, each of which extends opposite the lower free end facing 70 of a vertical control rod 42. The rods 68 can be controlled simultaneously towards their extended position illustrated in FIG. 10, or to a retracted position illustrated in Figure 1.

Two auxiliary cylinders 72, supplied independently with respect to the housing 66, act simultaneously, by their rods 74, on a horizontal degassing plate to move it vertically in both directions between a low position illustrated in FIG. 10 and a high degassing position illustrated in Figures 11.

Each vertical rod 42 for controlling and compensating for the weight of the intermediate plate with which it is associated comprises a radial flange 78 for degassing.

As can be seen in Figures 10 and 11, the flanges 78 are vertically offset from each other as a function of the vertical offset of the plates with which they are associated.

In FIG. 10, the control box 44 hydraulically balances the entire stacking of the plates by the cooperation of the rods 68 with lower ends 70 of the vertical bars 42, the lower ends 70 all being at the same altitude .

When it is desired to degas the molds, the degassing plate 76 is mounted, by means of the auxiliary jacks 72, then the action of the main jack 28 and of the weight compensating jacks 68 are released.

The degassing plate 76, cooperating with the degassing flanges 78, then retains the vertical bars 72 in the desired degassing position corresponding to a partial opening of each mold.

intermediate opening position for degassing, the hydraulic compensation of the weight of the plates and the complete opening and closing of the press are, thanks to the teachings of the invention, obtained without using additional racks which increase the size of all of the press which create phenomena of mechanical interference like that known in the state of the art.

the number of parts of reduced complex design and the main mechanical components which perform the functions mentioned above are arranged outside the polygon formed by the columns and the plates. The columns can thus be brought as close as possible to the plates, which makes it possible to reduce the footprint on the floor of the press, to reduce the dimension of the box springs 22 and 24 for equivalent rigidity, to facilitate access to the various moving parts and to facilitate replacement of wearing parts to maintain the press.

As a variant not shown, the upper upper plate of the stack can be replaced by the fixed upper plate PSF, and is no longer necessary to provide a stop B.

Claims (10)

<U> CLAIMS </U> 1. Press (20), in particular for molding and / or pressure cooking of friction linings, comprising a stack of plates among which the fixed upper plate (PSF) for reaction and mobile lower plate (PIM) for clamping under the action a jack (28, 30) for pressurizing the stacking of the plates, and comprising a series of intermediate plates mounted to slide freely along vertical guide supports (26), characterized in that it comprises at at least one pair of intermediate plates (PRi, PHi) among which a lower reference plate (PRi) is provided with a device (Ci, Ti) which associates the two upper plates (PHi) and bottom (PBi) which are adjacent, which is linked in vertical translation to this reference plate (PRi) and which determines the maximum position up, respectively down, of the high plate (PHi), respectively bottom (PBi), associated with respect to the plate of reference (PRi), and in that the high plate (PH3) associated with the reference plate (PR3) of the highest pair (PR3, PH3) of intermediate plates is immobilized in vertical translation downwards when the press (20) is opened. 2. Press according to the preceding claim, characterized in that said high plate (PH3) associated with the reference plate (PR3) of the highest pair (PR3, PH3) of intermediate plates is immediately adjacent fixed upper reaction plate (PSF ). 3. Press according to one of claims 1 or 2, characterized in that it comprises at least two successive pairs (PR1, PHI, PR2, PH2) of intermediate plates, and in that the low plate (PB2) adjacent to the reference plateau (PR2) of the upper pair (PR2, PH2) is the high plateau (PHI) adjacent to the reference plateau (PR1) of the lower pair (PHI PHI). 4. Press according to any one of the preceding claims, characterized in that the movable clamping plate (PIM) is the bottom plate (PBI) associated with the reference plate (PR1) of the lowest pair (PR1, PHI) of intermediate plates. 5. Press according to any one of the preceding claims, characterized in that the association device (Ci) is a C-shaped element whose vertical branch (48) is fixed along a lateral edge of the plate reference (PRi) and whose upper horizontal branch (50), respectively lower (52), extends opposite a portion of the upper face of the associated upper plate (PHi), respectively of the lower face of the associated lower plate (PBi). 6. Press according to any one of the preceding claims, characterized in that the association device (Ti) is a vertical rod whose central section is fixed to the reference plate (PRi) and whose high end section, respectively bottom, is received by sliding through a hole (62) formed in the top plate (PHi), respectively bottom (PBi), associated and is provided at its free end with a radial flange (50, 52) which extends in view of a portion of the upper face of the associated upper plate (PHi), respectively of the lower face of the associated lower plate (PBi). 7. Press according to any one of the preceding claims, characterized in that each plate is a rectangular plate, and in that each of the two parallel and opposite lateral edges (34) of a reference plate (PRi) provided with two devices of association (Ci, Ti) spaced transversely. 8. Press according to any one of the preceding claims, characterized in that each intermediate plate carries a half-mold (Mli, MSi) on each of its opposite faces. 9. Press according to any one of the preceding claims, characterized in that each plate provided, along one of its edges (36), with a horizontal bar (38) which is guided in vertical sliding by means of pads (41) carried vertical structural elements (26) in the form of columns. 10. Press according to any one of the preceding claims, characterized in that each plate carries a vertical control bar (42) which extends downwards and comprises a radial flange (78) for degassing on which a plate acts. degassing (76) actuated by degassing jacks (72).