FR2659037A1 - DEBURRING MACHINE FOR MOLDED METAL PARTS. - Google Patents

Abstract

The deburring machine, usable for die-cast metal parts, comprises a press having blank receiving means (10) and a tool (38), movable vertically towards said means, for separating the casting blank. in waste and useful part (12). These means comprise a counter tool (26) having, from a breaking edge of the as-cast part, a steep downward slope. These means are connected to a fixed frame by support means (24, 22) having surfaces inclined downwards and defining wide openings allowing debris to fall through these openings.

Description

i

  DEBURRING MACHINE FOR MOLDED METAL PARTS

  The present invention relates to a machine

  deburring of metal parts obtained by molding.

  It finds a particularly important application in the workshops for manufacturing metal parts cast under pressure and in particular in light alloy. Mention may be made, by way of examples, of parts cast in aluminum or in a foundry alloy such as "zamac" which, after machining. , constitute the body of an internal combustion engine supply device, in particular the tank of a carburetor or the throttle body of an injection system. The blank that comes out of a pressure molding press consists of the useful part and metal blocks solidified during casting in the mold and connected to the useful part by thin parts When the useful part is of complex shape , the correct filling of the mold can only be obtained at the cost of producing a raw part comprising waste whose weight may exceed 60% of that of the raw product, divided into fragments of very variable mass (casting jet, heavy weight; flyweight; washing heel;

burr; etc).

  Part deburring machines are already known, used in automated workshops, of the type comprising a press having means for receiving the raw part and

  a tool, movable vertically towards the receiving means

  tion, intended to separate the waste from the useful part.

  On this press, the raw part is placed on a horizontal plate. Its weight keeps it in place during deburring, which avoids the use of clamping means of the part in position But, the evacuation of waste casting on these machines poses a problem which is only very imperfectly solved In general, the casting jet, which is the most bulky waste, is seized and transferred to a waste bin by the robot which is used to bring the raw part Small waste, such as weights, is evacuated by gravity in gutters in principle, but experience shows that many engorgements occur. Light debris falls on the press bed or on the ground Their dispersion

  interferes with manufacturing and causes incidents.

  It has also been proposed to use a deburring press with a vertical plate for receiving the blank and a tool with horizontal displacement.

  fall under the press and can be collected direct-

  ment in a container This solution complicates installation It notably prohibits automatic centering by gravity on guide cones and therefore requires maintaining

the part during deburring.

  The present invention aims in particular to provide a deburring machine of the type defined above which better meets those previously known than the requirements of practice, in particular in that it facilitates the collection and

waste recovery.

  For this purpose, the invention proposes a machine character-

  characterized in that said receiving means comprise a counter-tool having, from a breaking edge of the blank between the useful part and the waste, a significant downward slope and in that the counter-tool is connected to a fixed frame by means also having surfaces inclined downward and delimiting large openings allowing debris to fall into a container. The absence of a horizontal or gently sloping surface

  avoids the retention of waste around the counter-tool The rup-

  ture between useful part and waste is advantageously pro-

  embossed by driving in the useful part by a tool movable vertically by a hydraulic cylinder and intended to bear on the edges of the useful part and to push the useful part by pushing back a support plate for useful part; this plate can be supported by a fluid pressure counter-cylinder, making it possible to exert a lifting force of the plate lower than the force of the

first cylinder.

  The invention will be better understood on reading the

  description which follows of a particular embodiment

  of the invention, given by way of nonlimiting example La

  description refers to the accompanying drawings, in

which:

  Figure 1 is a schematic view of a machine

  ne, in elevation and in partial section along a vertical plane

  tical passing through the axis of the tool, Figure 2 is a schematic top view of Figure 1, Figures 3 A and 3 B show representative sections of shapes that can take the arms supporting the tool, in section along line III-III of Figure 2, Figure 4 is an elevational view in partial section on a large scale, showing a possible form of tool and counter-tool, Figure 5 is a top view showing the counter-tool of FIG. 4 and a rough part to be trimmed, FIGS. 6 and 7, similar to FIGS. 1 and 2, show a possible construction of machines also comprising horizontal jacks,

  FIG. 8 is a view on the left of FIG. 6.

  The machine shown diagrammatically in FIGS. 1 and 2 is intended for deburring raw foundry parts 10 comprising a useful part 12 to which waste remains attached, such as for example a casting jet 14,

  weights 16 and burrs (not shown) We assume

  will be in what follows that the useful part to be detached is

  limited by a circular line, but any other shape would be acceptable, especially since the line is

in one plane.

  The machine comprises a fixed and robust frame, having a frame 18 carried by feet 20 and connected by radial arms 22 to a central crown table 24 for receiving a counter-tool 26 The counter-tool has an edge directed towards the top and whose line reproduces that of the breaking line of the part 10 This line is flat but

  could have offsets On an internal cy-

  lindrique of the counter-tool slides with soft friction a stripper plate 28 for reception whose shape in plan

  is that of the useful part 12 The external face of the counter

  tool has a high downward slope, advantageously higher than

  greater than 450, so that loose debris will slide

  along the counter-tool 26 and pass through the wide openings

  res delimited by the crown 24 and the arms 22, which constitute

  form a counter-tool support means 26 The outer face of the crown 24 also has a high downward slope and is connected to that of the counter-tool

  26 The arms consist of solid bars or tu-

  binoculars which either have a straight section with a steep slope, with no significant horizontal upper part (case of Figure 3 A), or else are covered with a deflector

  on a roof 30 with a steep slope (Figure 3B).

  In the embodiment shown in Figures 1 and 2, the plate 28, provided with means 32 for centering the useful part 12, is carried by the piston of a counter-cylinder 34 whose

  the cylinder is connected, by webs 36, to the crown 24.

  The diameter of the cylinder of the counter-cylinder 34 is much smaller than that of the crown 24, so as to avoid the catching of debris on the cylinder.

  the top of the plate 28 can be limited by the support of the pis-

  tone of the counter-cylinder 34 against the cylinder or by external means In its highest position, the plate maintains the part 10 above the edge of the counter-tool 26. The rupture of the raw part 10 is caused by the descent of a tool 38 which can be secured to the piston of a jack 40 The fixed cylinder of the jack 40 can in particular be carried by a bracket 42 secured to the frame 18 The tool 38 has a bearing surface on the blank, the external contour of which corresponds to that of the edge of the counter-tool 26 The jack 40 is designed to exert sufficient force to overcome the opposing force exerted by the jack 34 and the shear resistance of the part

gross 10.

  A container 44 can be brought between the feet 20 of the machine, in order to collect all the waste

detached, and removed.

  Figures 4 and 5 (o the elements already shown in Figures 1 and 2 have the same reference number)

  show an example of tool 38 and counter-tool 26, used

  readable for deburring a useful part 12 constituted by a throttle body for an internal combustion engine injection device In FIGS. 4 and 5, the waste to be

  separate are shown in dashed lines The body

  ant the useful part is in the form of a disc deli-

  mitered by a circular ridge, having a central injector holder connected by two wings to lateral bosses projecting upwards and downwards, all these elements being

  drilled with fuel and air passage holes.

  The counter-tool 26 is in the form of an annular block with a prismatic outer face, with two slopes and a cylindrical internal bore, limited upwards by the breaking edge. In the bore slides the plate 28,

  removably attached to the piston 46 of the lower cylinder.

  The tool 38 has a coping intended to be applied against the disk of the useful part 12 and a recess of sufficient size to accommodate the injector holder and the bosses. This tool is removably attached to the piston 48

of the upper cylinder 40.

  The plate 28 has recesses making it possible to accommodate the bosses The lifting of the plate 28 under the action of the counter-cylinder is limited by abutment of a plate, integral with the plate 28, against the crown which carries

  the counter-tool This coming into abutment occurs at a level

  calf such that the blank is immediately above the edge of the counter tool 26. When the blank foundry to be trimmed has holes, the latter often remain closed by thin scales from molten metal which has slid between the drawers intended to reserve the openings and the holes These holes often open transversely to the plane of separation of the waste, defined by the breaking edge. To perform, in a single operation, the deburring of the part by rupture along the connection line of large waste and the clearance of the holes, one can use a machine of the kind shown in Figures 6 to 8 (where the organs corresponding to those of FIGS. 1 to 5

  still have the same reference number).

  The machine of FIGS. 6 to 8 comprises a transverse jack 52, the piston of which can receive a tool 54 for unblocking the holes oriented parallel to a first direction x and which can also be used to hold the blank foundry piece pressed against an anvil 56 during the unblocking of the holes oriented in an orthogonal direction y, using a second tool controlled by a jack 58 It is possible to provide a

  additional cylinder 60 for clamping and / or unclogging.

  In the case considered above of deburring of foundry parts intended to constitute throttle bodies, the jack 40 can have a stroke of several tens of millimeters, to free the space necessary for the establishment and removal of the parts, and exerting a force of approximately 10 tonnes. The counter-cylinder 34 can have a very short stroke, of a few centimeters, and

  can yield under a force of the order of a tonne

  rins 52 and 58 can be provided with a stroke of tens of centimeters and to exert a force of the same

  order of magnitude as the counter-cylinder 34.

  The weight of the waste such as scales and burrs may be insufficient to slide it along the

walls to container 44.

  To remove these burrs and barbs, the counter tool can be fitted with compressed air passages connecting nozzles

  blowing to nozzles 62 fitted to the crown table.

  The nozzles are then connected to a central supply

  tion in air, comprising a valve which opens during a

  duration determined each time the actuator 40 is moved

when lifting the tool 38.

  The machine operation follows directly

  from the above description A robot brings each piece

  gross in turn and placing it on the plate 28, provided with centering and possibly orientation means, then

that the tool 38 is lifted.

  The jack 40 is then pressurized to provo-

  quer the lowering of the tool This tool 38 comes to rest on the disc of the foundry part 10, pushes the part

  useful 12 by fracturing the junction zones with the

  chets and pushes back the piston of the counter-cylinder 34

  the transverse clamping cylinder, as well as the cylinders

  transverse unblocking sets are set in motion after

  center of the piston of the jack 40 and cutting of the blank.

  The waste falls into container 44.

  The double-acting cylinder 40 is then actuated in the direction of ascent and raises the tool 38 Under the action of the pressure prevailing in the counter-cylinder 34 (which can

  be simple effect) the useful part returns to its posi-

  original tion At the same time, the direct air nozzles

  gent on the tray and the room of the air jets which drive out

  the beards possibly deposited.

  Finally, when the tool has returned to the high position, the useful part can be removed with the same robot which is then used to bring in a new raw part. The same press can be provided to receive various types of tool, counter-tool and plate, chosen according to the shape of the parts useful to produce. The press can be controlled automatically as well as manually.

Claims (4)

  1 machine for deburring molded metal parts, comprising a press having means for receiving the raw part (10) and a tool (38), movable vertically towards the said means, for separating the raw part from the foundry into waste and useful part (12), characterized in that said means comprise a counter-tool (26) having, from a breaking edge of the blank foundry, a high downward slope and in that said means are connected to a fixed frame by support means (24,22) having surfaces inclined downward and delimiting large openings allowing debris to fall through these openings. 2 Machine according to claim 1, characterized in that said tool (38) is designed to rest on the   useful part and sink into the counter tool (26).   3 Machine according to claim 2, characterized in that the workpiece receiving means also comprise a plate (28), sliding vertically in the counter-tool (26), carried by a fluid pressure cylinder (34).   4 Machine according to claim 3, characterized in that the plate (28) is provided with means for centering the useful part and means limiting its vertical upward movement to a position for which the line of separation between useful part and waste East   immediately above the edge of the tool holder. Machine according to any one of   previous claims, characterized in that said   support means comprise a crown (24) for receiving the counter-tool (26) and link arms (22)   with a frame (18) of the frame, with faces inclined downwards.   6 Machine according to claim 5, characterized in that the arms consist of solid or tubular bars elongated in the vertical direction or by bars covered with a deflector (30) whose faces   have a high downward slope.