ADJUSTABLE DIE ASSEMBLY

Abstract: This invention relates to an arrangement at lower tools for edging presses and the like where a pair of jaws or pads are displaceable in at least the one direction by means of a system including obliquely arranged surfaces. The novelty lies in that there are arranged at a first sliding face of a sliding plate or the like part connected to a frame, a number of slots or recesses (3) in pairs and positioned in opposing directions on each side of a central plane of the tool and at second inverted sliding faces each connected to a jaw or pad means (12) mirror inverted slots (8) having greater length than the former slots and in that in the shorter slots there are arranged keys having a depth adapted to the slots so that a protruding portion of each key projects into each of the elongated slots.

Description: ADJUSTABLE DIE ASSEMBLY Technical field of the invention This invention relates to lower tools for edging or folding presses and other sheet metal forming machines and more in detail to lower tools having laterally adjustable pads or abutments. Background of the invention WO 91/03332 discloses an arrangement having two pad halves laterally displaceable on a support portion of the lower tool on each sides of the central plane of the tool, wherein the lateral movement in closing direction is achieved by intermediary bodies having obliquely arranged surfaces engaging a straight abutment rod and also engaging complementary obliquely arranged surfaces at the two pad halves in order to make those approach each other. A relative displacement in separating direction is achieved by blade spring means mounted between the pad halves and biassed in such a way that they urge to separate those. The locking in the positions reached is achieved by the engagement between the obliquely arranged surfaces and consequently the pulling device has to be extremely precise in its movements in order to avoid play. Further, there is a demand for the pad halves to be equipped with a foot portion having large width enough in order to maintain the lateral stability required. Purpose of the invention One aspect of the invention is to bring about an arrangement where the pad halves or jaws besides a simple way be precisely displaced relatively to each other also can be rigidly locked in each position reached and are supported in such a way that risk for turning over is eleminated. Summary of the invention This invention is based on the idea that during displacement in the longitudinal direction of the lower tool of the two pad parts or halves cause the obliquely arranged surfaces thereof, by means of an intermediary connecting or guiding body to cooperate with obliquely arranged surfaces at one relatively to the pad parts movable part in order to achieve lateral displacement of the pad parts from and towards each other and that by means of locking means displaceable in the length direction of the lower tool and engaging essentially similarily obliquely and sloping surfaces at the pad parts cause a locking or fixation of those as well mutually as relatively to the stationary part of the lower tool . Furthermore, the driving for the displaceable locking means is arranged in such a way that the necessary displacement of the locking means is at a minimum and consequently quick. Description of the drawings A preferred embodiment of the invention will be described more in detail in the following with references to the attached drawings, on which Figure 1 is a fragmentary total view of a lower tool arranged according to the invention, Figure 2 is a section along the line A-A of Figure 1, Figure 3 is a top view of the essentially stationary base plate of the lower tool, Figure 4 is a section view along the line B-B of Figure 3, Figures 5 and 6 are top views of the two pad parts, Figure 7 is a section along the line C-C of Figure 6, Figure 8 is an end view in enlarged scale of one of the locking means, Figure 9 is a side view of the same locking means, and Figure 10 is a top view of the locking means. Detailed description of preferred embodiment On the drawings only details necessary for the understanding of the invention have been included and other details for the sake of clarity only indicated by dashed lines. On a bottom frame not shown in details there is arranged a base or slide plate 1 and this one which is illustrated in Figures 3 and 4 has a number of stepped undercut through slot like recesses 2 arranged one after the other along the center line and obliquely arranged bottom recesses arranged in pairs on each side of the center line. It is to be noted that on the drawing only two groups of recesses are shown whereas in reality the number is greater. The bottom recesses 3 arranged in pairs have bores 4 for screws with countersunks for the screw heads on the lower side of the plate 1. The slots 3 are adapted to the dimensions of an intended to receive standard keys 5, which completely fill each such recess and are secured therein by means of screws. The depth of the recesses 3 is so related to the thickness of the keys 5 that a portion of each key projects above the surface of the slide plate 1. Two holder rods 7 are arranged to be supported by the slide 1 and the holder rods have on their lower side obliquely arranged elongated slots 8 arranged in pairs with the same pitch as the bottom recesses 3 of the slide plate 1. The depth of the slots 8 is essentially equal with the depth of the recesses 3. It is essential that the depth of the slots 8 is that large that there is a play between the upper face of a key 5 projecting into the holder rod slot 8 from below and secured inside the bottom recess 3 of the slide plate and the inner or upper bottom surface of the holder rod slot 8. By this arrangement it is prevented that the holder rod will be supported by the key instead of as intended the upwardly facing surface of the slide plate. The length of the bottom slots 8 of the holder rods 7 is much greater than the length of the recesses 3 of the slide plate. The bottom slots 8 arranged at the lower side of each holder rod are like the bottom recesses 3 of the slide plate mutually in parallel and are localized in the same angle relatively to the longitudinal axis X. The angle has the same value on both sides of its axis but opposite to each other. The considerably greater length of the slots 8 arranged at the holder rods 7 and that of the recesses 3 of the slide plate 2 implies that the holder rods 7 may be displaced relatively to the slide plate 1 and on such displacement the holder rods 7 not only move in the longitudinal direction of the slide plate 1 but also laterally. The holder rods 7 are connected to a common ram device 9 mounted on a bracket 10 by means of screws 11 secured to the end of the slide plate 1 and by means of this ram device the holder rods 7 may be displaced in the one or the other longitudinal direction whereby they also will move towards and from each other depending on in which direction their longitudinal displacement takes place. The holder rods 7 are the whole time guided by force by means of the engagement of the keys in the slots 8. The guiding takes place in an exact and uniform way along the whole length of the tool. At each holder rod 7 there is a pad part or so called jaw 12 secured by means of screws 13 and it is laterally positioned by means of flat keys 14. Each of the holder rods 7 and one jaw 12 thus forms a unit . In order to bring about a stable and non yielding locking and anchoring of the holder rods 7 with the jaws 12 in reached positions of displacement, there is a system of locking bosses 15. Each locking boss 15 includes, as can be seen from Figures 8-10, a shaft portion 16 at its lower end equipped with a cross piece 17 and at its upper end with frusto conical head 19 having a radial bore 18 and being axially cut so that two parallel end faces 20 appear. As also appears from Figures 1 and 2 there are a number of locking bosses 15 threaded on to a threaded rod 22 and by means of nuts 21 stably anchored thereto. At one end of the rod there is a piston and cylinder arrangement or the like power driven handling means 23. The handling means 23 is by means of an intermediary piece 24 secured to the slide plate 1 by means of bolts 25, which means that the position relatively thereto is constant . The edges of the holder rods 7 facing each other have partly curved obliquely arranged abutment surfaces 26, which are inclined in an angle to the plane of the slide plate corresponding to the tapering of the heads 19 of the locking bosses 15 and besides that inclined relatively to the longitudinal axis X in angle values corresponding to the angles in which the recesses 3 and slots 8 are oriented. The abutment surfaces 26 are in pairs arranged opposite to the positions for the inclined long slots 8 and the through recesses 2 and run along the distances along which the keys 5 partly countersunk in the slide plate may be displaced along the long slots 8 of the holder rods . The movement of the locking bosses in the length direction is limited by means of the cross piece at the lower part thereof projecting down through the longitudinal through recesses 2 where the cross piece 17 runs in the widened lower portion and blocks the movement of the locking bosses upwardly. On the changing of the set position for the jaws 12, to start with, a driving means 23 for the rod 22 carrying the locking bosses is biassed so that each locking boss is displaced to the area between the engagement surfaces where the distance between those is the biggest. The locking bosses in that way form no obstacle on the continued setting operation. The jaws 12 are positioned as mentioned before by activating the driving means 9 which pulls or pushes the slide plate in one or the other direction which as said before results in an approaching or a separation of the jaws. On reaching intended position of the jaws the driving means for the rod carrying locking bosses is activated and displaces the locking bosses towards the narrower end of the areas laterally defined by the inclined surfaces of engagement. On the locking bosses with their inwardly inclined curved portions engages inclined surfaces of engagement of the holder rods 7 those will be stably locked in intended positions and then the holder rods carrying the jaws will not be movable by longitudinal displacement of the slide plate 1. The locking bosses with their downwardly inclined curved side portions cooperating with the inclined surfaces of engagement of the holder rods and the keys preventing mutual displacement between the holder rods and the slide plate form a very secure locking against outwardly overturning of the jaws 12.

Claims: C L A I S 1. Lower tool for edging or folding presses and other sheet metal forming machines especially lower tools having laterally adjustable pads or jaws arranged in pairs, wherein displacement in at least the one direction is achieved by means of inclined surfaces engaging each other at mutually displaceable parts, c h a r a c t e r i z e d in that there is, at a preferably downwardly facing sliding surface connected to respective pad or jaw (12) , a number of elongated recesses (8) inclined relatively to the longitudinal direction of the jaws, and also the tool, wherein the recesses of the one jaw is opposite to that of the other, that there are in an opposite preferably upwardly facing sliding surface (1) connected to the machine frame in essentially corresponding longitudinal positions mirror inverted inclined slot like seats (3) , wherein the elongated recesses are essentially longer than the slot shaped seats (3) and in that in each of the seats (3) there is essentially non-displaceably anchored a guiding body (5) having a length and a width adapted to the said seat and a height that much exceeding the depth of the seat that part of the guiding body projects out of the seat and is receivable in the mirror inverted obliquely arranged longer recess in the opposite sliding surface in order to, on displacement in the longitudinal direction of the jaws arranged in pairs relatively to the opposite sliding surface (1) , the cooperation of the guiding bodies (5) and the elongated recesses (8) brings about also a mutual lateral displacement of the jaws. 2. Tool according to claim 1, c h a r a c t e r i z e d in that the sliding surface (1) against which the sliding faces of the jaws or pads (12) slide is the upper surface of a slide plate (1) displaceably arranged relatively to the frame of the edging press, the obliquely arranged slot like seats (3) being arranged in said surface, that the sliding face of each of the jaw means is one side of a holder rod (7) secured at each jaw or pad means (12) in which a surface serving as a sliding surface the long recesses (8) arranged and in that the guiding bodies (15) which have a length and a width adapted to the short seats (3) are constituted by elements shaped as keys (5) . 3. Tool according to claim 2, c h a r a c t e r i z e d in that in the slide plate (1) are arranged a number of through elongated longitudinal recesses (2) , that the holder rods (7) displaceable along the slide plate (1) at their edges facing towards each other have obliquely cut surfaces (26) essentially in parallel with the elongated recesses (8) arranged at each holder rod (7) , locking bosses (15) being received within the recesses and limitedly displaceable therein, said locking bosses having lateral surface portions arranged obliquely corresponding to the obliquely cut surfaces (26) of the holder rods, that the locking bosses (15) together are displaceable each one in its recess (2) by means of a rigid driving means connecting the locking bosses and movable in the longitudinal direction of the tool in order to, on reaching engagement with the obliquely cut surfaces (26) of the holder rods in cooperation with the guiding bodies (5) non displaceably arranged in the slot like seats (3) in the sliding surface (1) of the machine frame and the elongated slot like recesses (8) at the sliding surfaces of the pads or the jaws for bringing about a rigid positioning of the holder rods (7) .

Inventors: ROENNMARK ULF, ROENNMARK, ULF
Applicants: NYA URSVIKENS MEKANISKA VERKST, ROENNMARK ULF, NYA URSVIKENS MEKANISKA VERKSTADS AB, ROENNMARK, ULF
Application year: 1993
Main classification: B21D5
IPC codes: B21D5