EP1910037B1 - Pneumatic assembly for a sand removal installation for foundry cores - Google Patents

Pneumatic assembly for a sand removal installation for foundry cores Download PDF

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Publication number
EP1910037B1
EP1910037B1 EP06778805A EP06778805A EP1910037B1 EP 1910037 B1 EP1910037 B1 EP 1910037B1 EP 06778805 A EP06778805 A EP 06778805A EP 06778805 A EP06778805 A EP 06778805A EP 1910037 B1 EP1910037 B1 EP 1910037B1
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EP
European Patent Office
Prior art keywords
air
travel cylinder
pneumatic assembly
bore
barrel
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Active
Application number
EP06778805A
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German (de)
French (fr)
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EP1910037A1 (en
Inventor
Vi Pham Dinh
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Les Outils Pneumatiques Globe
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Les Outils Pneumatiques Globe
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Publication of EP1910037A1 publication Critical patent/EP1910037A1/en
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D29/00—Removing castings from moulds, not restricted to casting processes covered by a single main group; Removing cores; Handling ingots
    • B22D29/001—Removing cores
    • B22D29/005—Removing cores by vibrating or hammering
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D17/00—Details of, or accessories for, portable power-driven percussive tools
    • B25D17/06—Hammer pistons; Anvils ; Guide-sleeves for pistons
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D17/00—Details of, or accessories for, portable power-driven percussive tools
    • B25D17/20—Devices for cleaning or cooling tool or work
    • B25D17/22—Devices for cleaning or cooling tool or work using pressure fluid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D9/00—Portable percussive tools with fluid-pressure drive, i.e. driven directly by fluids, e.g. having several percussive tool bits operated simultaneously
    • B25D9/14—Control devices for the reciprocating piston
    • B25D9/16—Valve arrangements therefor
    • B25D9/20—Valve arrangements therefor involving a tubular-type slide valve
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D2209/00—Details of portable percussive tools with fluid-pressure drive, i.e. driven directly by fluids, e.g. having several percussive tool bits operated simultaneously
    • B25D2209/005—Details of portable percussive tools with fluid-pressure drive, i.e. driven directly by fluids, e.g. having several percussive tool bits operated simultaneously having a tubular-slide valve, which is coaxial with the piston
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D2216/00—Details of portable percussive machines with superimposed rotation, the rotational movement of the output shaft of a motor being modified to generate axial impacts on the tool bit
    • B25D2216/0007—Details of percussion or rotation modes
    • B25D2216/0015—Tools having a percussion-only mode
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D2250/00—General details of portable percussive tools; Components used in portable percussive tools
    • B25D2250/101—Emitting warning signals, e.g. visual or sound
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D2250/00—General details of portable percussive tools; Components used in portable percussive tools
    • B25D2250/221—Sensors

Definitions

  • Such a pneumatic assembly is known from the document FR-A-2742365 .
  • the drum is attached to a support vis-à-vis a workpiece to be de-sanded, itself attached to the support.
  • the approach cylinder is in the retracted position with the rivet knife away from the workpiece.
  • the supply of compressed air is then fed so that the approach cylinder is advanced from its retracted position to its working position.
  • the stroke of the cylinder is longer or shorter depending on the original distance between the free end of the rivet and the workpiece.
  • the striking means When the free end of the rivet comes into contact with the workpiece, the striking means enter into operation.
  • These striking means consist of a piston performing reciprocating movements in a bore of the approach cylinder, under the effect of the air pressure.
  • this pneumatic assembly has the disadvantage that sand from the parts being sanded tend to be introduced into the apparatus between the guiding and retaining flange and the approach cylinder. This sand disrupts the operation of the tire assembly, and causes premature wear. It also causes an increase in the frequency of maintenance operations.
  • the document DE 8900887 U (Froelich ), which describes a pneumatic assembly for the grit removal of foundry cores.
  • approach and striking are dissociated.
  • the document DE 89 00 887 U teaches a pneumatic assembly comprising a striking device.
  • Said striking device is mounted in a piston sliding in an outer hollow cylinder, the latter constituting a jack, so that the striking device can be brought, together with the piston, in a piston approaching movement from a retracted position to a working position where the rivet is in contact with a work piece.
  • the approach movement is achieved by the arrangement of the striking device together with the piston and its cylinder.
  • This arrangement causes significant bulk and heavy operation since it is the assembly consisting of the striking device and the piston that moves to move from a retracted position to a working position.
  • This heaviness of the device according to the document DE 89 00 887 U leads to favoring a vertical working position to minimize the mechanical forces, which limits its use.
  • the present invention aims to provide a pneumatic assembly for grit removal of foundry cores comprising a mechanism for approaching striking means of a workpiece that can greatly limit the introduction of sand or dust inside the assembly, and thus reduce the maintenance operations of the whole while fighting against premature wear, regardless of the retracted position, working or intermediate approach mechanism and the state of operation or not of the striking means.
  • the barrel is hollow and, at the outlet of the barrel, is fixed the guide and retaining flange to guide the sliding of the approach cylinder, said flange comprising said bore.
  • the blowing air may especially be a non-lubricated air.
  • the compressed air used for the movements of the approach cylinder and the striking is a lubricated air to ensure the lubrication of the moving parts.
  • it can be used for blowing dry air to maintain the cleanliness of the connection zone between the cylinder and the barrel.
  • the supply pressure is not detected and the air intake means are inhibited so that the approach cylinder and the striking means are not actuated.
  • the supply pressure is not detected when the rivet is not mounted on the approach cylinder, in which case the inhibition of the air inlet means occurs in the absence of detection.
  • said drilling in the wall of the approach cylinder is connected to said pipe via a bore formed in the wall of the guide flange and retainer vis-à-vis the drilling in the wall of the approach cylinder when the approach cylinder is in the retracted position.
  • the compressed air whose feed pressure is detected by the pressure switch is from the same source as the blowing air.
  • the non-lubricated air inlets are thus grouped at the level of the guide and retaining flange.
  • the invention also relates to a grit removal system, comprising a pneumatic assembly as described above.
  • the grit hammer shown in the figures comprises firstly a barrel 1 provided with fastening means 2 for mounting the hammer in a grit removal facility.
  • An approach cylinder 3 is slidably mounted in a bore 4 of the barrel 1 from which it protrudes, and supports at its free outer end to the barrel a 5. The end of the barrel opposite the exit of the approach cylinder is closed.
  • front of the hammer will be referred to here as the direction of the free end of the approach cylinder and the rivet 5, and "backward” in the opposite direction, namely that of the closed end of the barrel 1.
  • the approach cylinder 3 slides in the barrel 1 of a retracted position ( figures 6 , 9 and 16 ) at a work position ( figures 10 and 17 ) where the free end of the rivet is in abutment on a piece to be removed. It will be seen below that, if nothing limits the stroke of the approach cylinder, it comes into over-travel position ( figures 7 and 18 ).
  • the outer surface of the approach cylinder 3 bears on the surface of the bore 4 in two sealing and guiding zones.
  • a first zone is formed by a median bead 6 carrying a seal 7 at the front with the bore 4, behind which is formed an annular groove arranged to receive a guide segment 8.
  • a second zone is formed by a hammer head 9 screwed to the rear of the approach cylinder 3, and whose outer surface carries a seal 10 behind a guide segment 11.
  • a guide and retaining flange 12 is mounted on the barrel by means of screws 13.
  • the flange 12 receives in a suitable annular groove a seal 14 with the approach cylinder 3, and maintains against a shoulder of the bore 4 a resilient stop before 15.
  • the stop 15 is provided to come into contact with a shoulder 16 before the bead 6 when the approach cylinder 3 is in over-stroke position ( figure 8 ).
  • the O-rings 7, 10 and 14 delimit two chambers between the outer surface of the approach roll 3 and the the bore 4, respectively a rear chamber 17 between the seals 7 and 10 and a front chamber 18 between the seals 7 and 14.
  • Another chamber 19 is formed at the rear of the approach cylinder 3, between the seal 10 and the bottom of the barrel 1. It will be seen below that when the chambers 17 and 19 communicate, they form a first compression chamber, while the chamber 18 forms a second compression chamber.
  • the barrel 1 is provided at its closed end with a port 20 for the admission of compressed air, capable of connecting the chamber 19 to a source of compressed air via a connector 21.
  • the air source compressed is also capable of being connected to the chamber 18 via a connector 22 mounted on an orifice 23 formed in the wall of the barrel 1 immediately behind the elastic abutment 15.
  • the chamber 17 is capable of be vented through a fitting 24 mounted on an orifice 25 formed in the wall of the barrel 1 immediately behind the bead 6 when the approach cylinder 3 is in its retracted position and forward of the seal 10 when the approach cylinder 3 is in its over-stroke position.
  • the wall of the barrel 1 is pierced by a hole 26 which is behind the seal 7 when the approach cylinder 3 is in over-stroke position abutting the elastic abutment 15.
  • the hole 26 thus opens into the chamber 17 when the approach cylinder 3 is in this position.
  • a connector 27 is mounted on the hole 26 to connect the hole 26 to a pressure switch.
  • the bore 28 of the guide and retaining flange 12 is provided with two annular grooves in front of the mounting groove of the seal 14 ( figure 8 ).
  • the front groove forms an annular chamber 29 connected by a bore 30 in the wall of the flange 12 to a coupling 31 which can be connected to a source of high pressure air.
  • the annular chamber 29 is separated from the front face 32 of the flange 12 by a annular lip 33 forming a clearance with the outer surface of the approach cylinder 3, this clearance determining an annular blow orifice around the cylinder 3.
  • a wiper seal 34 is disposed in the annular chamber 29 ( figure 15 ).
  • the rear groove forms an annular chamber 35 connected by a bore 36 ( figures 6 and 15 ) in the wall of the flange 12 to a connector 37 may be connected to a source of high pressure air.
  • a bore 38 is furthermore formed in the wall of the approach cylinder 3 so as to open on the one hand into the bore 39 of the approach cylinder, and on the other hand into the annular chamber 35 when the cylinder of approach is in its retracted position.
  • the longitudinal location of the bore 39 of the approach cylinder 3 where the piercing 38 opens is normally occupied by the tail 40 of the rivet 5 when the rivet is mounted on the hammer.
  • the tail 40 of the rivet has an annular flange 41.
  • a flange mounting bracket 42 is made in two parts separated by an axial plane and held together by a retaining spring 43 engaged in a groove outer 44 of the flange 42.
  • the flange 42 is held axially on the approach cylinder 3 by means of an insert 45 also in two parts separated by an axial plane.
  • the insert 45 is partially engaged radially in two opposite annular grooves 46 and 47 respectively formed on the outer surface of the approach cylinder and on the inner surface of the flange 12.
  • the annular flange 41 is clamped between the front end face of the approach cylinder 3 and a washer forming a snap damper retained by an annular flange 49 of the flange 12.
  • a piston 50 is also slidably mounted in the bore 39 of the approach cylinder 3.
  • This piston 50 comprises a rear portion 51 of diameter corresponding to that of the bore 4 and a front portion 52 of smaller diameter.
  • the front portion 51 of the piston defines with the bore 39 of the approach cylinder 3 an annular volume 53.
  • valve 54 acting as a distributor moving in a valve box 55, associated with conduits, which will be described below, formed in the walls of the approach cylinder 3 and other organs also described below, makes it possible to make these movements to the piston under the action of the compressed air admitted through the orifice 20 and escaping through the orifice 25.
  • the valve 54 has a generally cylindrical outer casing in which two annular grooves 56 and 57 respectively are formed respectively.
  • the outer casing therefore forms three ranges: a trailing pad 58, a median pad 59 between the two grooves, and a front pad 60.
  • the valve 54 comprises a generally conical axial separation web 61, having at its apex a seat 62 substantially in the rear end plane of the valve, for a calibrated orifice which will be described hereinafter.
  • Valve box 55 is a generally cylindrical annular member whose outer surface 63 is substantially cylindrical.
  • the surface 64 of the bore of the valve box 55 comprises a set of annular milling forming grooves in circular arcs. From the rear towards the front, these milling forms the grooves 65, 66 and 67 cooperating with the grooves 56 and 57 of the valve 54. Another groove 68 cooperates with the groove 56, holes 69 passing through the wall of the box with a valve 55 opening at the bottom of the groove 68. Finally, another groove 70 is formed foremost in the surface of the bore 64.
  • the front face 71 of the valve box 55 has a cavity 72 ( figures 8 and 12 ) communicating with holes 73 which open into the grooves 65 and 66 for the return of the cylinder.
  • valve 54 is retained in the bore 64 of the valve box 55 forwards by the rear face 90 of the approach cylinder 3 and rearwardly by a valve box cover 91.
  • the cover 91 has an axial bore 92 whose front end forms a calibrated orifice 93 which has been discussed above. This orifice 93 is able to bear on the seat 62 by sliding the valve 54 in the bore 64 and thus be closed.
  • a set of peripheral holes 94 also generally pass axially through the cover 91, however, moving away from the rear towards the front.
  • the bores 94 communicate with axial bores formed in the valve box 55, these axial bores opening into the groove 70.
  • the rear part of the hammer head 9 comprises a plastic plug 100 forming a damper. Holes 101 allow the admission of the high pressure into the apparatus.
  • the wall of the hammer head 9 has holes 110 opening into grooves 111 ( figure 8 ) allowing the connection to the exhaust.
  • Bores 120 distributed circumferentially and converging forwardly through the wall of the approach cylinder 3 towards the bore 39, from the rear shoulder 121 of the bead 6 where they thus open into the chamber 17.
  • a radial bore 122 through which the function will be explained below, is also formed in the wall of the approach cylinder 3, opening into the annular space 53 when the approach cylinder 3 is in its retracted position.
  • a ring 123 engaged in a ring groove formed in the bore 39 guides the front portion 52 of the piston 50 while in this position.
  • a blind hole 124 opens into the bore 39 in the extension of the bore 122, which is plugged by a plug 125.
  • the bore 124 communicates with radial bores in the wall of the approach cylinder 3 for feeding and venting.
  • Compressed air is fed through a pipe 201 of a compressor not shown to a filter 202 and then to a pressure regulator 203. From there, a portion of the compressed air is fed through a pipe 204 to a lubricator 205, while the other part is used non-lubricated as will be described below.
  • Lubricated compressed air is fed through line 206 to a two-way electropneumatic distributor 207.
  • One channel 208 is connected to the connector 21 and the other channel 209 is connected to the connector 22 to respectively provide forward and reverse movements of the approach cylinder 3.
  • the non-lubricated compressed air is led on the one hand by a pipe 210 to a blowing valve 211 and thence to the coupling 31. It is, on the other hand, led via a pipe 212 to a valve 213 and from there to the connection 37 via a conduit 214.
  • a pressure switch 215 is connected on the pipe 214 for the presence detection of the rivet 5 on the approach cylinder 3.
  • the connector 27 is connected via a line 216 to a pressure switch 217 for the over-travel detection of the approach cylinder 3.
  • connection 24 is connected by a pipe 218 to a valve 219 and from there to a venting pipe 220.
  • the pneumatic or electropneumatic equipment that has just been described is electrically connected by lines not shown to a programmable controller 225 which controls the equipment so as to ensure the programmed operation of the grit hammer.
  • the sandblasting hammer which has just been described operates in the following manner.
  • An operating cycle starts with the retracted approach cylinder 3, by detecting the presence of the rivet 5 on the approach cylinder 3.
  • the bore 38 is in communication with the valve 213 through the annular chamber 35, the bore 36, the connector 37 and the pipe 214.
  • the valve 213 is then open. If the rivet is absent, the pressure switch 215 detects no pressure.
  • the cycle is interrupted and an alarm is generated.
  • the cycle can also be interrupted if the detected pressure is below a certain threshold, which indicates an abnormal level of leakage.
  • the bore 38 is plugged so that the pressure switch 215 detects a pressure.
  • the valve 213 is then closed and the cycle continues.
  • valve 219 is closed, which has the effect of blocking the escape of the chamber 17. This blocking has the effect of inhibiting the drive of the piston 50 until the valve 219 is subsequently opened .
  • the distributor 207 is then controlled so as to bring the lubricated compressed air to the connection 21 and thence to the chamber 19 and then to the chamber 17.
  • the approach cylinder 3 advances under the effect of the compressed air until it comes into abutment, either against a workpiece via the rivet 5, or by contacting its shoulder 16 with the abutment 15.
  • the next step is to detect if a workpiece is absent, that is to say, if the approach cylinder 3 comes into over travel abutting against the stopper 15. In this case, the seal 7 exceeds the hole 26 which has the effect of putting the pressure switch 217 in communication with the high pressure of the chamber 17 via the connector 27 and the pipe 216. When this high pressure is detected, the cycle is interrupted, the supply of compressed air is cut by the distributor 207 and an alarm is generated.
  • the blast valve 211 is opened to blow an air curtain around the approach cylinder 3, and the vent valve 219 free of the chamber 17 is opened so as to start the striking of the rivet by the piston 50.
  • the typing step is broken down into cycles of three phases illustrated respectively in Figures 22a, 22b and 22c .
  • the piston 50 is in advance phase.
  • the high pressure is exerted on the rear face 230 of the piston via the groove 70.
  • the groove 66 is exhausted through the annular groove 56 and the holes 69.
  • the valve 54 is held in position. rear position by the high pressure in the groove 70, with the calibrated orifice 93 resting on the seat 62.
  • valve 54 was brought into the advanced position by the high pressure.
  • the piston 50 hits the rivet 5 and bounces.
  • Groove 65 is under pressure and valve 54 is pressed forward.
  • the distributor interrupts the compressed air supply of the coupling 21 to supply the connection 22 via the pipe 209.
  • the striking stops and the chamber 18 is fed, which has the effect of pushing the approach cylinder 3 back while the air in the chambers 17 and 19 escapes via the connector 24 and the valve 219.
  • the cycle is complete when the approach roll 3 has returned to its retracted position and the blow valve 211 is closed.

Description

La présente invention concerne un ensemble pneumatique pour installation de dessablage des noyaux de fonderie, et plus particulièrement un tel ensemble comprenant :

  • un fût comportant des moyens d'arrivée d'air comprimé et des moyens d'évacuation d'air ;
  • un cylindre d'approche monté coulissant dans le fût sous l'action de l'air comprimé, entre une position rétractée et une position de travail où une bouterolle montée à l'extrémité libre du cylindre d'approche est en contact avec une pièce de travail ;
  • des moyens de frappe pour imprimer, sous l'action de l'air comprimé, des chocs répétés sur l'extrémité de la bouterolle opposée à son extrémité de contact avec la pièce de travail.
The present invention relates to a pneumatic assembly for grit removal of foundry cores, and more particularly to such an assembly comprising:
  • a drum comprising means for supplying compressed air and means for exhausting air;
  • an approach cylinder slidably mounted in the drum under the action of the compressed air, between a retracted position and a working position where a rivet mounted at the free end of the approach cylinder is in contact with a piece of job ;
  • typing means for printing, under the action of compressed air, repeated shocks on the end of the rivet opposite its end of contact with the workpiece.

Un tel ensemble pneumatique est connu par le document FR-A-2742365 .Such a pneumatic assembly is known from the document FR-A-2742365 .

Dans l'installation décrite dans ce document, le fût est fixé à un support en vis-à-vis d'une pièce de travail à dessabler, elle-même fixée au support. En début de cycle de dessablage, le cylindre d'approche est en position rétractée avec la bouterolle à l'écart de la pièce de travail.In the installation described in this document, the drum is attached to a support vis-à-vis a workpiece to be de-sanded, itself attached to the support. At the start of the grit cycle, the approach cylinder is in the retracted position with the rivet knife away from the workpiece.

L'arrivée d'air comprimé est alors alimentée de sorte que le cylindre d'approche est avancé de sa position rétractée à sa position de travail. La course du cylindre est plus ou moins longue en fonction de la distance d'origine entre l'extrémité libre de la bouterolle et la pièce de travail.The supply of compressed air is then fed so that the approach cylinder is advanced from its retracted position to its working position. The stroke of the cylinder is longer or shorter depending on the original distance between the free end of the rivet and the workpiece.

Lorsque l'extrémité libre de la bouterolle arrive au contact de la pièce de travail, les moyens de frappe entrent en fonctionnement. Ces moyens de frappe consistent en un piston effectuant des déplacements alternatifs dans un alésage du cylindre d'approche, sous l'effet de la pression d'air.When the free end of the rivet comes into contact with the workpiece, the striking means enter into operation. These striking means consist of a piston performing reciprocating movements in a bore of the approach cylinder, under the effect of the air pressure.

Enfin, l'alimentation en air comprimé est coupée de sorte que les frappes sont interrompues. Le cylindre d'approche est ramenée en position rétractée sous l'effet d'un ressort de rappel.Finally, the supply of compressed air is cut off so that the strikes are interrupted. The approach cylinder is returned to the retracted position under the effect of a return spring.

Bien que donnant généralement satisfaction, cet ensemble pneumatique présente l'inconvénient que du sable provenant des pièces en cours de dessablage a tendance à s'introduire dans l'appareil entre la bride de guidage et de retenue et le cylindre d'approche. Ce sable perturbe le fonctionnement de l'ensemble pneumatique, et en provoque une usure prématurée. Il cause par ailleurs une augmentation de la fréquence des opérations de maintenance.Although generally satisfactory, this pneumatic assembly has the disadvantage that sand from the parts being sanded tend to be introduced into the apparatus between the guiding and retaining flange and the approach cylinder. This sand disrupts the operation of the tire assembly, and causes premature wear. It also causes an increase in the frequency of maintenance operations.

On connaît également dans l'art antérieur, le document DE 8900887 U (Froelich ), qui décrit un ensemble pneumatique pour le dessablage des noyaux de fonderie. Dans cet ensemble pneumatique, l'approche et la frappe sont dissociées. En particulier, le document DE 89 00 887 U enseigne un ensemble pneumatique comprenant un dispositif de frappe. Ledit dispositif de frappe est monté dans un piston coulissant dans un cylindre creux extérieur, ce dernier constituant un vérin, de sorte que le dispositif de frappe puisse être amené, conjointement avec le piston, en un mouvement d'approche du piston depuis une position rétractée jusqu'à une position de travail où la bouterolle est en contact avec une pièce de travail. Ainsi, le mouvement d'approche est réalisé par l'agencement du dispositif de frappe conjointement avec le piston et son vérin. Cet agencement provoque un encombrement important et une lourdeur de fonctionnement puisque c'est l'ensemble constitué du dispositif de frappe et du piston qui se déplace pour passer d'une position rétractée à une position de travail. Cette lourdeur du dispositif selon le document DE 89 00 887 U conduit à privilégier une position de travail verticale pour minimiser les efforts mécaniques, ce qui limite son utilisation.Also known in the prior art, the document DE 8900887 U (Froelich ), which describes a pneumatic assembly for the grit removal of foundry cores. In this pneumatic assembly, approach and striking are dissociated. In particular, the document DE 89 00 887 U teaches a pneumatic assembly comprising a striking device. Said striking device is mounted in a piston sliding in an outer hollow cylinder, the latter constituting a jack, so that the striking device can be brought, together with the piston, in a piston approaching movement from a retracted position to a working position where the rivet is in contact with a work piece. Thus, the approach movement is achieved by the arrangement of the striking device together with the piston and its cylinder. This arrangement causes significant bulk and heavy operation since it is the assembly consisting of the striking device and the piston that moves to move from a retracted position to a working position. This heaviness of the device according to the document DE 89 00 887 U leads to favoring a vertical working position to minimize the mechanical forces, which limits its use.

La présente invention vise à proposer un ensemble pneumatique pour installation de dessablage des noyaux de fonderie comportant un mécanisme d'approche de moyens de frappe d'une pièce de travail qui permette de limiter fortement l'introduction de sable ou de poussière à l'intérieur de l'ensemble, et ainsi réduire les opérations de maintenance de l'ensemble tout en luttant contre son usure prématurée, quelque soit la position rétractée, de travail ou intermédiaire du mécanisme d'approche et l'état de mise en fonctionnement ou non des moyens de frappe.The present invention aims to provide a pneumatic assembly for grit removal of foundry cores comprising a mechanism for approaching striking means of a workpiece that can greatly limit the introduction of sand or dust inside the assembly, and thus reduce the maintenance operations of the whole while fighting against premature wear, regardless of the retracted position, working or intermediate approach mechanism and the state of operation or not of the striking means.

A cet effet, l'invention a pour objet un ensemble pneumatique pour installation de dessablage des noyaux de fonderie selon la revendication indépendante 1, comprenant :

  • un fût comportant des moyens d'arrivée d'air comprimé et des moyens d'évacuation d'air pulsé ;
  • un cylindre d'approche monté coulissant dans le fût sous l'action de l'air comprimé, entre une position rétractée et une position de travail où une bouterolle montée à l'extrémité libre du cylindre d'approche est en contact avec une pièce de travail ;
  • des moyens de frappe pour imprimer, sous l'action de l'air comprimé, des chocs répétés sur l'extrémité de la bouterolle opposée à son extrémité de contact avec la pièce de travail ; et
cet ensemble comprenant en outre une chambre annulaire formée dans une bride de guidage et de retenue montée à l'avant du fût et reliée par un perçage à un raccord susceptible d'être connecté à une source d'air à haute pression pour créer, au niveau de l'emplacement où le cylindre d'approche pénètre dans le fût, un rideau d'air autour du cylindre d'approche.For this purpose, the subject of the invention is a pneumatic assembly for a grinding installation of foundry cores according to independent claim 1, comprising:
  • a drum comprising means for supplying compressed air and means for discharging pulsed air;
  • an approach cylinder slidably mounted in the drum under the action of the compressed air, between a retracted position and a working position where a rivet mounted at the free end of the approach cylinder is in contact with a piece of job ;
  • typing means for printing, under the action of compressed air, repeated shocks on the end of the rivet opposite its end of contact with the workpiece; and
this assembly further comprising an annular chamber formed in a guide and retainer flange mounted at the front of the barrel and connected by a bore to a connector capable of being connected to a source of high pressure air to create, at the level of the location where the approach cylinder enters the barrel, a curtain of air around the approach cylinder.

Ainsi, l'air comprimé qui fuit entre le bord de la bride de guidage et de retenueet le cylindre d'approche provoque un soufflage autour du cylindre, ce soufflage repoussant le sable à l'extérieur de l'appareil.Thus, the compressed air leaking between the edge of the guide and retaining flange and the approach cylinder causes a blow around the cylinder, this blowing pushing the sand outside the device.

Dans un mode de réalisation particulier :

  • le cylindre d'approche pénètre dans le fût à travers un alésage ;
  • la chambre annulaire est formée dans la surface de l'alésage, séparée de l'extrémité libre de l'alésage par une lèvre annulaire agencée pour permettre une fuite d'air entre le bord de la lèvre et le cylindre d'approche, et comprennent en outre des moyens pour amener de l'air comprimé dans ladite chambre.
In a particular embodiment:
  • the approach cylinder enters the barrel through a bore;
  • the annular chamber is formed in the surface of the bore, separated from the free end of the bore by an annular lip arranged to allow air leakage between the edge of the lip and the approach cylinder, and comprise further means for supplying compressed air to said chamber.

Plus particulièrement, le fût est creux et, à la sortie du fût, est fixée la bride de guidage et de retenue pour guider le coulissement du cylindre d'approche, ladite bride comportant ledit alésage.More particularly, the barrel is hollow and, at the outlet of the barrel, is fixed the guide and retaining flange to guide the sliding of the approach cylinder, said flange comprising said bore.

L'air de soufflage peut notamment être un air non lubrifié.The blowing air may especially be a non-lubricated air.

L'air comprimé utilisé pour les déplacements du cylindre d'approche et la frappe est un air lubrifié pour assurer la lubrification des pièces en mouvement. Toutefois, on pourra utiliser pour le soufflage un air sec afin de maintenir la propreté de la zone de liaison entre le cylindre et le fût.The compressed air used for the movements of the approach cylinder and the striking is a lubricated air to ensure the lubrication of the moving parts. However, it can be used for blowing dry air to maintain the cleanliness of the connection zone between the cylinder and the barrel.

Egalement dans un mode de réalisation particulier, l'ensemble pneumatique selon l'invention comprend :

  • une chambre annulaire formée dans la bride et reliée par un perçage à un raccord susceptible d'être connecté à la source d'air à haute pression et à un pressostat, et
  • un perçage pratiqué dans la paroi du cylindre d'approche de manière à déboucher d'une part dans un alésage du cylindre d'approche, d'autre part dans la chambre annulaire lorsque le cylindre d'approche est dans sa position rétractée,
la bouterolle comprenant une queue qui, lorsque la bouterolle est montée à l'extrémité libre du cylindre d'approche, occupe l'emplacement longitudinal de l'alésage du cylindre d'approche dans lequel débouche le perçage de sorte que la queue de la bouterolle bouche le perçage,
pour que, par le pressostat, soit détectée la présence, respectivement l'absence, d'une pression d'alimentation en air comprimé supérieure à un seuil prédéterminé, et donc la présence, respectivement l'absence de la bouterolle lorsque le cylindre d'approche est dans sa position rétractée et qu'une bouterolle est montée sur le cylindre d'approche ; et
  • des moyens d'inhibition pour inhiber lesdits moyens d'arrivée d'air, lorsque la présence de la bouterolle n'est pas détectée.
Also in a particular embodiment, the pneumatic assembly according to the invention comprises:
  • an annular chamber formed in the flange and connected by a bore to a connector capable of being connected to the source of high pressure air and to a pressure switch, and
  • a hole made in the wall of the approach cylinder so as to open on the one hand into a bore of the approach cylinder and on the other hand into the annular chamber when the approach cylinder is in its retracted position,
the rivet comprising a tail which, when the rivet is mounted at the free end of the approach cylinder, occupies the longitudinal location of the bore of the approach cylinder in which the piercing opens out so that the tail of the rivet mouth piercing,
so that, by the pressure switch, the presence or absence of a compressed air supply pressure higher than a predetermined threshold is detected, and thus the presence or absence of the snap ring when the cylinder of approach is in its retracted position and a rivet is mounted on the approach cylinder; and
  • inhibition means for inhibiting said air intake means, when the presence of the rivet is not detected.

Les dispositifs de l'art antérieur présentaient l'inconvénient que qu'ils pouvaient être mis en fonctionnement même le cas où, par inadvertance, aucune bouterolle n'avait été montée sur le cylindre d'approche. Un tel fonctionnement est évidemment anormal et peut même s'avérer dangereux en cas d'éjection des moyens de frappe.The devices of the prior art had the disadvantage that they could be put into operation even if, inadvertently, no rivet had been mounted on the approach cylinder. Such operation is obviously abnormal and can even be dangerous in case of ejection of the striking means.

Il est par ailleurs souhaitable de pouvoir contrôler le degré d'usure et l'étanchéité des moyens de frappe, ce dont l'ensemble pneumatique connu n'est pas capable.It is also desirable to be able to control the degree of wear and tightness of the striking means, which the known tire assembly is not capable of.

Grâce à cette dernière disposition, dans un mode de réalisation, dans le cas où la bouterolle n'est pas montée sur le cylindre d'approche, la pression d'alimentation n'est pas détectée et les moyens d'arrivée d'air sont inhibés de sorte que le cylindre d'approche et les moyens de frappe ne sont pas mis en action. En variante, la pression d'alimentation n'est pas détectée lorsque la bouterolle n'est pas montée sur le cylindre d'approche, auquel cas l'inhibition des moyens d'arrivée d'air intervient en l'absence de détection.With this last arrangement, in one embodiment, in the case where the rivet is not mounted on the approach cylinder, the supply pressure is not detected and the air intake means are inhibited so that the approach cylinder and the striking means are not actuated. Alternatively, the supply pressure is not detected when the rivet is not mounted on the approach cylinder, in which case the inhibition of the air inlet means occurs in the absence of detection.

En détectant un seuil prédéterminé pour la pression d'alimentation, on peut contrôler une fuite caractéristique d'un défaut d'étanchéité résultant d'une usure des moyens de frappe.By detecting a predetermined threshold for the supply pressure, it is possible to control a characteristic leak of a leakage resulting from wear of the striking means.

Cette disposition peut d'ailleurs trouver application indépendamment des autres caractéristiques mentionnées ci-dessus.This provision can also find application independently of the other characteristics mentioned above.

Egalement dans un mode de réalisation particulier

  • la queue de montage de la bouterolle est sensiblement cylindrique
  • l'ensemble pneumatique comprend en outre une canalisation pour alimenter ledit perçage en air comprimé et le pressostat raccordé à ladite canalisation.
Also in a particular embodiment
  • the mounting tail of the rivet is substantially cylindrical
  • the tire assembly further comprises a pipe for supplying said piercing with compressed air and the pressure switch connected to said pipe.

Egalement dans un mode de réalisation particulier, ledit perçage dans la paroi du cylindre d'approche est relié à ladite canalisation par l'intermédiaire d'un perçage réalisé dans la paroi de la bride de guidage et de retenue en vis-à-vis du perçage dans la paroi du cylindre d'approche lorsque le cylindre d'approche est en position rétractée.Also in a particular embodiment, said drilling in the wall of the approach cylinder is connected to said pipe via a bore formed in the wall of the guide flange and retainer vis-à-vis the drilling in the wall of the approach cylinder when the approach cylinder is in the retracted position.

Egalement dans un mode de réalisation particulier, l'air comprimé dont la pression d'alimentation est détectée par le pressostat, est issu de la même source que l'air de soufflage.Also in a particular embodiment, the compressed air whose feed pressure is detected by the pressure switch, is from the same source as the blowing air.

On groupe ainsi au niveau de la bride de guidage et de retenue les arrivées d'air non lubrifié.The non-lubricated air inlets are thus grouped at the level of the guide and retaining flange.

L'invention a également pour objet une installation de dessablage, comprenant un ensemble pneumatique tel que décrit ci-dessus.The invention also relates to a grit removal system, comprising a pneumatic assembly as described above.

On décrira maintenant, à titre d'exemple non limitatif, un mode de réalisation particulier de l'invention, en référence aux dessins schématiques annexés dans lesquels :

  • la figure 1 est une vue extérieure en perspective d'un marteau de dessablage selon l'invention ;
  • la figure 2 est une vue en élévation selon la flèche II de la figure 1 ;
  • la figure 3 est une vue en perspective éclatée du marteau de dessablage de la figure 1 ;
  • la figure 4 est une vue à plus grande échelle du détail IV de la figure 3 ;
  • la figure 5 est une vue à plus grande échelle du détail V de la figure 3 ;
  • la figure 6 est une vue en coupe axiale simplifiée, notamment en ce qui concerne les plans de coupe, du marteau de dessablage de la figure 1 avec le cylindre d'approche en position rétractée ;
  • la figure 7 est une vue partielle similaire à la figure 6 avec le cylindre d'approche en position de travail ;
  • la figure 8 est une vue à plus grande échelle du détail VIII de la figure 7 ;
  • la figure 9 est une vue en coupe selon la ligne IX-IX de la figure 2 ;
  • la figure 10 est une vue en coupe selon la ligne X-X de la figure 2 ;
  • la figure 11 est une vue à plus grande échelle du détail XI de la figure 10 ;
  • la figure 12 est une vue à plus grande échelle du détail XII de la figure 9 ;
  • la figure 13 est une vue à plus grande échelle du détail XIII de la figure 9 ;
  • la figure 14 est une vue à plus grande échelle du détail XIV de la figure 10 ;
  • la figure 15 est une vue à plus grande échelle du détail XV de la figure 9 ;
  • la figure 16 est une vue en coupe selon la ligne XVI-XVI de la figure 2, avec le cylindre d'approche en position rétractée ;
  • la figure 17 est une vue similaire à la figure 16, avec le cylindre d'approche en position de travail ;
  • la figure 18 est une vue similaire à la figure 16, avec le cylindre d'approche en position de sur-course ;
  • la figure 19 est une vue à plus grande échelle du détail XIX de la figure 17 ;
  • la figure 20 est une vue à plus grande échelle du détail XX de la figure 16 ;
  • la figure 21 est un schéma pneumatique du marteau de dessablage de la figure 1 ; et
  • les figures 22a, 22b et 22c sont des schémas illustrant le fonctionnement du marteau de dessablage des figures précédentes.
A particular embodiment of the invention will now be described, by way of nonlimiting example, with reference to the appended diagrammatic drawings in which:
  • the figure 1 is an external perspective view of a sandblasting hammer according to the invention;
  • the figure 2 is an elevation view along arrow II of the figure 1 ;
  • the figure 3 is an exploded perspective view of the sandblasting hammer of the figure 1 ;
  • the figure 4 is a larger-scale view of detail IV of the figure 3 ;
  • the figure 5 is a larger-scale view of detail V of the figure 3 ;
  • the figure 6 is a simplified axial sectional view, in particular with regard to the section planes, of the grit removal hammer of the figure 1 with the approach cylinder in the retracted position;
  • the figure 7 is a partial view similar to the figure 6 with the approach cylinder in working position;
  • the figure 8 is a larger-scale view of detail VIII of the figure 7 ;
  • the figure 9 is a sectional view along the line IX-IX of the figure 2 ;
  • the figure 10 is a sectional view along line XX of the figure 2 ;
  • the figure 11 is a larger-scale view of detail XI of the figure 10 ;
  • the figure 12 is a larger-scale view of detail XII of the figure 9 ;
  • the figure 13 is a larger-scale view of detail XIII of the figure 9 ;
  • the figure 14 is a larger-scale view of detail XIV of the figure 10 ;
  • the figure 15 is a larger-scale view of detail XV of the figure 9 ;
  • the figure 16 is a sectional view along line XVI-XVI of the figure 2 , with the approach cylinder in the retracted position;
  • the figure 17 is a view similar to the figure 16 , with the approach cylinder in working position;
  • the figure 18 is a view similar to the figure 16 with the approach cylinder in over-stroke position;
  • the figure 19 is a larger-scale view of detail XIX of the figure 17 ;
  • the figure 20 is a larger-scale view of detail XX of the figure 16 ;
  • the figure 21 is a pneumatic diagram of the grit hammer of the figure 1 ; and
  • the Figures 22a, 22b and 22c are diagrams illustrating the operation of the grit hammer of the preceding figures.

Le marteau de dessablage représenté aux figures comprend en premier lieu un fût 1 muni de moyens de fixation 2 permettant de monter le marteau dans une installation de dessablage. Un cylindre d'approche 3 est monté coulissant dans un alésage 4 du fût 1 dont il dépasse, et supporte à son extrémité libre extérieure au fût une bouterolle 5. L'extrémité du fût opposée à la sortie du cylindre d'approche est fermée.The grit hammer shown in the figures comprises firstly a barrel 1 provided with fastening means 2 for mounting the hammer in a grit removal facility. An approach cylinder 3 is slidably mounted in a bore 4 of the barrel 1 from which it protrudes, and supports at its free outer end to the barrel a 5. The end of the barrel opposite the exit of the approach cylinder is closed.

On désignera ci-après par "avant" du marteau la direction de l'extrémité libre du cylindre d'approche et de la bouterolle 5, et par "arrière" la direction opposée, à savoir cette de l'extrémité fermée du fût 1.The term "front" of the hammer will be referred to here as the direction of the free end of the approach cylinder and the rivet 5, and "backward" in the opposite direction, namely that of the closed end of the barrel 1.

Le cylindre d'approche 3 coulisse dans le fût 1 d'une position rétractée (figures 6, 9 et 16) à une position de travail (figures 10 et 17) où l'extrémité libre de la bouterolle est en butée sur une pièce à dessabler. On verra ci-après que, si rien ne limite la course du cylindre d'approche, celui-ci vient en position de sur-course (figures 7 et 18).The approach cylinder 3 slides in the barrel 1 of a retracted position ( figures 6 , 9 and 16 ) at a work position ( figures 10 and 17 ) where the free end of the rivet is in abutment on a piece to be removed. It will be seen below that, if nothing limits the stroke of the approach cylinder, it comes into over-travel position ( figures 7 and 18 ).

La surface extérieure du cylindre d'approche 3 porte sur la surface de l'alésage 4 en deux zones d'étanchéité et de guidage. Une première zone est formée par un bourrelet médian 6 portant à l'avant un joint d'étanchéité 7 avec l'alésage 4, en arrière duquel est formée une rainure annulaire agencée pour recevoir un segment de guidage 8. Une deuxième zone est formée par une tête de marteau 9 vissée à l'arrière du cylindre d'approche 3, et dont la surface extérieure porte un joint d'étanchéité 10 en arrière d'un segment de guidage 11.The outer surface of the approach cylinder 3 bears on the surface of the bore 4 in two sealing and guiding zones. A first zone is formed by a median bead 6 carrying a seal 7 at the front with the bore 4, behind which is formed an annular groove arranged to receive a guide segment 8. A second zone is formed by a hammer head 9 screwed to the rear of the approach cylinder 3, and whose outer surface carries a seal 10 behind a guide segment 11.

A l'avant du fût 1, une bride de guidage et de retenue 12 est montée sur le fût à l'aide de vis 13. La bride 12 reçoit dans une rainure annulaire appropriée un joint d'étanchéité 14 avec le cylindre d'approche 3, et maintient contre un épaulement de l'alésage 4 une butée élastique avant 15. La butée 15 est prévue pour venir en contact avec un épaulement avant 16 du bourrelet 6 lorsque le cylindre d'approche 3 est en position de sur-course précitée (figure 8).At the front of the barrel 1, a guide and retaining flange 12 is mounted on the barrel by means of screws 13. The flange 12 receives in a suitable annular groove a seal 14 with the approach cylinder 3, and maintains against a shoulder of the bore 4 a resilient stop before 15. The stop 15 is provided to come into contact with a shoulder 16 before the bead 6 when the approach cylinder 3 is in over-stroke position ( figure 8 ).

Ainsi, les joints toriques 7, 10 et 14 délimitent deux chambres entre la surface extérieure du cylindre d'approche 3 et la surface de l'alésage 4, respectivement une chambre arrière 17 entre les joints 7 et 10 et une chambre avant 18 entre les joints 7 et 14. Une autre chambre 19 est formée à l'arrière du cylindre d'approche 3, entre le joint 10 et le fond du fût 1. On verra ci-après que, lorsque les chambres 17 et 19 communiquent, elles forment une première chambre de compression, tandis que la chambre 18 forme une deuxième chambre de compression.Thus, the O-rings 7, 10 and 14 delimit two chambers between the outer surface of the approach roll 3 and the the bore 4, respectively a rear chamber 17 between the seals 7 and 10 and a front chamber 18 between the seals 7 and 14. Another chamber 19 is formed at the rear of the approach cylinder 3, between the seal 10 and the bottom of the barrel 1. It will be seen below that when the chambers 17 and 19 communicate, they form a first compression chamber, while the chamber 18 forms a second compression chamber.

Le fût 1 est muni à son extrémité fermée d'un orifice 20 d'admission d'air comprimé, susceptible de connecter la chambre 19 à une source d'air comprimé par l'intermédiaire d'un raccord 21. La source d'air comprimé est également susceptible d'être connectée à la chambre 18 par l'intermédiaire d'un raccord 22 monté sur un orifice 23 formé dans la paroi du fût 1 immédiatement en arrière de la butée élastique 15. Enfin, la chambre 17 est susceptible d'être mise à l'air libre par l'intermédiaire d'un raccord 24 monté sur un orifice 25 formé dans la paroi du fût 1 immédiatement en arrière du bourrelet 6 lorsque le cylindre d'approche 3 est dans sa position rétractée et en avant du joint d'étanchéité 10 lorsque le cylindre d'approche 3 est dans sa position de sur-course.The barrel 1 is provided at its closed end with a port 20 for the admission of compressed air, capable of connecting the chamber 19 to a source of compressed air via a connector 21. The air source compressed is also capable of being connected to the chamber 18 via a connector 22 mounted on an orifice 23 formed in the wall of the barrel 1 immediately behind the elastic abutment 15. Finally, the chamber 17 is capable of be vented through a fitting 24 mounted on an orifice 25 formed in the wall of the barrel 1 immediately behind the bead 6 when the approach cylinder 3 is in its retracted position and forward of the seal 10 when the approach cylinder 3 is in its over-stroke position.

La paroi du fût 1 est percée d'un trou 26 qui se trouve en arrière du joint 7 lorsque le cylindre d'approche 3 est en position de sur-course en butée sur la butée élastique 15. Le trou 26 débouche donc dans la chambre 17 lorsque le cylindre d'approche 3 est dans cette position. Un raccord 27 est monté sur le trou 26 pour connecter le trou 26 à un pressostat.The wall of the barrel 1 is pierced by a hole 26 which is behind the seal 7 when the approach cylinder 3 is in over-stroke position abutting the elastic abutment 15. The hole 26 thus opens into the chamber 17 when the approach cylinder 3 is in this position. A connector 27 is mounted on the hole 26 to connect the hole 26 to a pressure switch.

L'alésage 28 de la bride de guidage et de retenue 12 est muni de deux rainures annulaires en avant de la rainure de montage du joint d'étanchéité 14 (figure 8).The bore 28 of the guide and retaining flange 12 is provided with two annular grooves in front of the mounting groove of the seal 14 ( figure 8 ).

La rainure avant forme une chambre annulaire 29 reliée par un perçage 30 dans la paroi de la bride 12 à un raccord 31 susceptible d'être connecté à une source d'air à haute pression. La chambre annulaire 29 est séparée de la face avant 32 de la bride 12 par une lèvre annulaire 33 formant un jeu avec la surface extérieure du cylindre d'approche 3, ce jeu déterminant un orifice annulaire de soufflage autour du cylindre 3. Un joint racleur 34 est disposé dans la chambre annulaire 29 (figure 15).The front groove forms an annular chamber 29 connected by a bore 30 in the wall of the flange 12 to a coupling 31 which can be connected to a source of high pressure air. The annular chamber 29 is separated from the front face 32 of the flange 12 by a annular lip 33 forming a clearance with the outer surface of the approach cylinder 3, this clearance determining an annular blow orifice around the cylinder 3. A wiper seal 34 is disposed in the annular chamber 29 ( figure 15 ).

La rainure arrière forme une chambre annulaire 35 reliée par un perçage 36 (figures 6 et 15) dans la paroi de la bride 12 à un raccord 37 susceptible d'être connecté à une source d'air à haute pression. Un perçage 38 est par ailleurs formé dans la paroi du cylindre d'approche 3 de manière à déboucher d'une part dans l'alésage 39 du cylindre d'approche, et d'autre part dans la chambre annulaire 35 lorsque le cylindre d'approche est dans sa position rétractée. L'emplacement longitudinal de l'alésage 39 du cylindre d'approche 3 où débouche le perçage 38 est normalement occupé par la queue 40 de la bouterolle 5 lorsque cette bouterolle est montée sur le marteau.The rear groove forms an annular chamber 35 connected by a bore 36 ( figures 6 and 15 ) in the wall of the flange 12 to a connector 37 may be connected to a source of high pressure air. A bore 38 is furthermore formed in the wall of the approach cylinder 3 so as to open on the one hand into the bore 39 of the approach cylinder, and on the other hand into the annular chamber 35 when the cylinder of approach is in its retracted position. The longitudinal location of the bore 39 of the approach cylinder 3 where the piercing 38 opens is normally occupied by the tail 40 of the rivet 5 when the rivet is mounted on the hammer.

Pour le montage de la bouterolle 5, la queue 40 de la bouterolle comporte un flasque annulaire 41. Une bride 42 de montage de bouterolle est réalisée en deux parties séparées par un plan axial et maintenues ensemble par un ressort de retenue 43 engagé dans une rainure extérieure 44 de la bride 42.For the mounting of the rivet 5, the tail 40 of the rivet has an annular flange 41. A flange mounting bracket 42 is made in two parts separated by an axial plane and held together by a retaining spring 43 engaged in a groove outer 44 of the flange 42.

La bride 42 est maintenue axialement sur le cylindre d'approche 3 à l'aide d'un insert 45 également en deux parties séparées par un plan axial. L'insert 45 est partiellement engagé radialement dans deux rainures annulaires en vis-à-vis 46 et 47 formées respectivement à la surface extérieure du cylindre d'approche et à la surface intérieure de la bride 12. Le flasque annulaire 41 est bridé entre la face d'extrémité avant du cylindre d'approche 3 et une rondelle 48 formant amortisseur de bouterolle retenue par un rebord annulaire 49 de la bride 12.The flange 42 is held axially on the approach cylinder 3 by means of an insert 45 also in two parts separated by an axial plane. The insert 45 is partially engaged radially in two opposite annular grooves 46 and 47 respectively formed on the outer surface of the approach cylinder and on the inner surface of the flange 12. The annular flange 41 is clamped between the front end face of the approach cylinder 3 and a washer forming a snap damper retained by an annular flange 49 of the flange 12.

Un piston 50 est par ailleurs monté coulissant dans l'alésage 39 du cylindre d'approche 3. Ce piston 50 comprend une partie arrière 51 de diamètre correspondant à celui de l'alésage 4 et une partie avant 52 de diamètre inférieur. Ainsi, la partie avant 51 du piston délimite avec l'alésage 39 du cylindre d'approche 3 un volume annulaire 53.A piston 50 is also slidably mounted in the bore 39 of the approach cylinder 3. This piston 50 comprises a rear portion 51 of diameter corresponding to that of the bore 4 and a front portion 52 of smaller diameter. Thus, the front portion 51 of the piston defines with the bore 39 of the approach cylinder 3 an annular volume 53.

Lorsque le marteau de dessablage est en action avec la bouterolle en contact avec une pièce à dessabler, le piston effectue des mouvements de va-et-vient entre une position arrière qui sera exposée ci-après et une position avant au contact de la queue 40 de la bouterolle 5. Une valve 54 faisant office de distributeur en se déplaçant dans une boîte à valve 55, associée à des conduits, qui vont être décrits ci-après, ménagés dans les parois du cylindre d'approche 3 et d'autres organes également décrits ci-après, permet de faire effectuer ces mouvements au piston sous l'action de l'air comprimé admis par l'orifice 20 et s'échappant par l'orifice 25.When the grit hammer is in action with the rivet in contact with a workpiece, the piston moves back and forth between a rear position to be exposed hereinafter and a forward position in contact with the tail 40 5. A valve 54 acting as a distributor moving in a valve box 55, associated with conduits, which will be described below, formed in the walls of the approach cylinder 3 and other organs also described below, makes it possible to make these movements to the piston under the action of the compressed air admitted through the orifice 20 and escaping through the orifice 25.

La valve 54 présente une enveloppe extérieure généralement cylindrique dans laquelle sont formées deux gorges annulaires respectivement arrière 56 et avant 57. L'enveloppe extérieure forme donc trois plages : une plage arrière 58, une plage médiane 59 entre les deux gorges, et une plage avant 60. Intérieurement, la valve 54 comporte un voile 61 de séparation axiale généralement conique, présentant à son sommet un siège 62 sensiblement dans le plan d'extrémité arrière de la valve, pour un orifice calibré qui sera décrit ci-après.The valve 54 has a generally cylindrical outer casing in which two annular grooves 56 and 57 respectively are formed respectively. The outer casing therefore forms three ranges: a trailing pad 58, a median pad 59 between the two grooves, and a front pad 60. Inwardly, the valve 54 comprises a generally conical axial separation web 61, having at its apex a seat 62 substantially in the rear end plane of the valve, for a calibrated orifice which will be described hereinafter.

La boîte à valve 55 est un organe généralement cylindrique annulaire dont la surface extérieure 63 est sensiblement cylindrique.Valve box 55 is a generally cylindrical annular member whose outer surface 63 is substantially cylindrical.

La surface 64 de l'alésage de la boîte à valve 55 comporte un ensemble de fraisures annulaires formant des rainures en arcs de cercle. De l'arrière vers l'avant, ces fraisures forment les rainures 65, 66 et 67 coopérant avec les gorges 56 et 57 de la valve 54. Une autre rainure 68 coopère avec la gorge 56, des perçages 69 traversant la paroi de la boîte à valve 55 débouchant au fond de la rainure 68. Enfin, une autre rainure 70 est formée le plus en avant dans la surface de l'alésage 64.The surface 64 of the bore of the valve box 55 comprises a set of annular milling forming grooves in circular arcs. From the rear towards the front, these milling forms the grooves 65, 66 and 67 cooperating with the grooves 56 and 57 of the valve 54. Another groove 68 cooperates with the groove 56, holes 69 passing through the wall of the box with a valve 55 opening at the bottom of the groove 68. Finally, another groove 70 is formed foremost in the surface of the bore 64.

La face avant 71 de la boîte à valve 55 comporte une cavité 72 (figures 8 et 12) communiquant avec des perçages 73 qui débouchent dans les rainures 65 et 66 pour le retour du cylindre.The front face 71 of the valve box 55 has a cavity 72 ( figures 8 and 12 ) communicating with holes 73 which open into the grooves 65 and 66 for the return of the cylinder.

La valve 54 est retenue dans l'alésage 64 de la boîte à valve 55 vers l'avant par la face arrière 90 du cylindre d'approche 3 et vers l'arrière par un couvercle 91 de boîte à valve.The valve 54 is retained in the bore 64 of the valve box 55 forwards by the rear face 90 of the approach cylinder 3 and rearwardly by a valve box cover 91.

Le couvercle 91 comporte un perçage axial 92 dont le fond avant forme un orifice calibré 93 dont il a été question ci-dessus. Cet orifice 93 est susceptible de venir en appui sur le siège 62 par coulissement de la valve 54 dans l'alésage 64 et ainsi d'être obturé. Un ensemble de perçages périphériques 94 traversent par ailleurs généralement axialement le couvercle 91, en s'écartant toutefois de l'arrière vers l'avant. Les perçages 94 communiquent avec des perçages axiaux ménagés dans la boîte à valve 55, ces perçages axiaux débouchant dans la rainure 70.The cover 91 has an axial bore 92 whose front end forms a calibrated orifice 93 which has been discussed above. This orifice 93 is able to bear on the seat 62 by sliding the valve 54 in the bore 64 and thus be closed. A set of peripheral holes 94 also generally pass axially through the cover 91, however, moving away from the rear towards the front. The bores 94 communicate with axial bores formed in the valve box 55, these axial bores opening into the groove 70.

La partie arrière de la tête de marteau 9 comprend un bouchon en matière plastique 100 formant amortisseur. Des orifices 101 permettent l'admission de la haute pression dans l'appareil.The rear part of the hammer head 9 comprises a plastic plug 100 forming a damper. Holes 101 allow the admission of the high pressure into the apparatus.

Dans sa partie médiane, la paroi de la tête de marteau 9 comporte des perçages 110 débouchant dans des rainures 111 (figure 8) permettant la liaison à l'échappement.In its median part, the wall of the hammer head 9 has holes 110 opening into grooves 111 ( figure 8 ) allowing the connection to the exhaust.

Des perçages 120 répartis circonférentiellement et convergents vers l'avant traversent la paroi du cylindre d'approche 3 vers l'alésage 39, à partir de l'épaulement arrière 121 du bourrelet 6 où ils débouchent donc dans la chambre 17. Un perçage radial 122 traversant dont la fonction sera expliquée ci-après, est également formé dans la paroi du cylindre d'approche 3, débouchant dans l'espace annulaire 53 lorsque le cylindre d'approche 3 est dans sa position rétractée. Un jonc 123 engagé dans une gorge annulaire formée dans l'alésage 39 guide la partie avant 52 du piston 50 alors qu'il est dans cette position.Bores 120 distributed circumferentially and converging forwardly through the wall of the approach cylinder 3 towards the bore 39, from the rear shoulder 121 of the bead 6 where they thus open into the chamber 17. A radial bore 122 through which the function will be explained below, is also formed in the wall of the approach cylinder 3, opening into the annular space 53 when the approach cylinder 3 is in its retracted position. A ring 123 engaged in a ring groove formed in the bore 39 guides the front portion 52 of the piston 50 while in this position.

Enfin, un perçage borgne 124 débouche dans l'alésage 39 dans le prolongement du perçage 122, lequel est bouché par un bouchon 125. Le perçage 124 communique avec des perçages radiaux ménagés dans la paroi du cylindre d'approche 3 pour l'alimentation et la mise à l'air libre.Finally, a blind hole 124 opens into the bore 39 in the extension of the bore 122, which is plugged by a plug 125. The bore 124 communicates with radial bores in the wall of the approach cylinder 3 for feeding and venting.

Si l'on se réfère maintenant à la figure 21, on voit le marteau de dessablage muni de ses raccords 21, 22, 24, 27, 31 et 37 décrits ci-dessus. Des conduites sont connectées sur ces raccords et sortent d'une cabine de dessablage 200 dans laquelle est monté le marteau, pour le relier à des équipements pneumatiques ou électropneumatiques qui seront décrits ci-après, mais qui sont tous situés à l'extérieur de la cabine 200. Ces équipements ne sont donc pas soumis aux conditions agressives régnant dans la cabine. Il est en outre facile d'assurer leur maintenance.If we now refer to the figure 21 the grit hammer is shown with its connections 21, 22, 24, 27, 31 and 37 described above. Pipes are connected to these connections and out of a grit chamber 200 in which is mounted the hammer, to connect it to pneumatic or electropneumatic equipment which will be described below, but which are all located outside the cabin 200. This equipment is therefore not subject to aggressive conditions in the cabin. It is also easy to maintain them.

De l'air comprimé est amené par une conduite 201 d'un compresseur non représenté à un filtre 202 puis à un régulateur de pression 203. De là, une partie de l'air comprimé est amenée par une conduite 204 à un lubrificateur 205, tandis que l'autre partie est utilisée non lubrifiée comme cela sera décrit ci-après.Compressed air is fed through a pipe 201 of a compressor not shown to a filter 202 and then to a pressure regulator 203. From there, a portion of the compressed air is fed through a pipe 204 to a lubricator 205, while the other part is used non-lubricated as will be described below.

L'air comprimé lubrifié est amené par une conduite 206 à un distributeur électropneumatique 207 à deux voies. Une voie 208 est connectée au raccord 21 et l'autre voie 209 est connectée au raccord 22 pour assurer respectivement les mouvements d'avance et de recul du cylindre d'approche 3.Lubricated compressed air is fed through line 206 to a two-way electropneumatic distributor 207. One channel 208 is connected to the connector 21 and the other channel 209 is connected to the connector 22 to respectively provide forward and reverse movements of the approach cylinder 3.

L'air comprimé non lubrifié est amené d'une part par une conduite 210 à une vanne de soufflage 211 et de là au raccord 31. Il est d'autre part amené par une conduite 212 à une vanne 213 et de là au raccord 37 par l'intermédiaire d'une conduite 214. Un pressostat 215 est connecté sur la conduite 214 pour la détection de présence de la bouterolle 5 sur le cylindre d'approche 3.The non-lubricated compressed air is led on the one hand by a pipe 210 to a blowing valve 211 and thence to the coupling 31. It is, on the other hand, led via a pipe 212 to a valve 213 and from there to the connection 37 via a conduit 214. A pressure switch 215 is connected on the pipe 214 for the presence detection of the rivet 5 on the approach cylinder 3.

Le raccord 27 est relié par une conduite 216 à un pressostat 217 pour la détection de sur-course du cylindre d'approche 3.The connector 27 is connected via a line 216 to a pressure switch 217 for the over-travel detection of the approach cylinder 3.

Enfin, le raccord 24 est relié par une conduite 218 à une vanne 219 et de là à une conduite de mise à l'air libre 220.Finally, the connection 24 is connected by a pipe 218 to a valve 219 and from there to a venting pipe 220.

Les équipements pneumatiques ou électropneumatiques qui viennent d'être décrits sont reliés électriquement par des lignes non représentées à un automate programmable 225 qui commande ces équipements de manière à assurer le fonctionnement programmé du marteau de dessablage.The pneumatic or electropneumatic equipment that has just been described is electrically connected by lines not shown to a programmable controller 225 which controls the equipment so as to ensure the programmed operation of the grit hammer.

Le marteau de dessablage qui vient d'être décrit fonctionne de la manière suivante.The sandblasting hammer which has just been described operates in the following manner.

Un cycle de fonctionnement débute avec le cylindre d'approche 3 rétracté, par la détection de présence de la bouterolle 5 sur le cylindre d'approche 3. Dans cette position du cylindre d'approche 3, le perçage 38 est en communication avec la vanne 213 par l'intermédiaire de la chambre annulaire 35, du perçage 36, du raccord 37 et de la conduite 214. La vanne 213 est alors ouverte. Si la bouterolle est absente, le pressostat 215 ne détecte aucune pression. Le cycle est interrompu et une alarme est générée. On peut également interrompre le cycle si la pression détectée est inférieure à un certain seuil, ce qui traduit un niveau de fuite anormal.An operating cycle starts with the retracted approach cylinder 3, by detecting the presence of the rivet 5 on the approach cylinder 3. In this position of the approach cylinder 3, the bore 38 is in communication with the valve 213 through the annular chamber 35, the bore 36, the connector 37 and the pipe 214. The valve 213 is then open. If the rivet is absent, the pressure switch 215 detects no pressure. The cycle is interrupted and an alarm is generated. The cycle can also be interrupted if the detected pressure is below a certain threshold, which indicates an abnormal level of leakage.

Si la bouterolle est présente, le perçage 38 est bouché de sorte que le pressostat 215 détecte une pression. La vanne 213 est alors fermée et le cycle continue.If the rivet is present, the bore 38 is plugged so that the pressure switch 215 detects a pressure. The valve 213 is then closed and the cycle continues.

En premier lieu, la vanne 219 est fermée, ce qui a pour effet de bloquer l'échappement de la chambre 17. Ce blocage a pour effet d'inhiber l'entraînement du piston 50 jusqu'à ce que la vanne 219 soit ultérieurement ouverte. Le distributeur 207 est alors commandé de manière à amener l'air comprimé lubrifié au raccord 21 et de là, à la chambre 19 puis à la chambre 17. Le cylindre d'approche 3 avance sous l'effet de l'air comprimé jusqu'à ce qu'il vienne en butée, soit contre une pièce de travail par l'intermédiaire de la bouterolle 5, soit par contact de son épaulement 16 avec la butée 15.Firstly, the valve 219 is closed, which has the effect of blocking the escape of the chamber 17. This blocking has the effect of inhibiting the drive of the piston 50 until the valve 219 is subsequently opened . The distributor 207 is then controlled so as to bring the lubricated compressed air to the connection 21 and thence to the chamber 19 and then to the chamber 17. The approach cylinder 3 advances under the effect of the compressed air until it comes into abutment, either against a workpiece via the rivet 5, or by contacting its shoulder 16 with the abutment 15.

L'étape suivante consiste à détecter si une pièce de travail est absente, c'est-à-dire si le cylindre d'approche 3 vient en sur-course en butée sur la butée 15. Dans ce cas, le joint d'étanchéité 7 dépasse le trou 26 ce qui a pour effet de mettre le pressostat 217 en communication avec la haute pression de la chambre 17 par l'intermédiaire du raccord 27 et de la conduite 216. Lorsque cette haute pression est détectée, le cycle est interrompu, l'alimentation en air comprimé est coupée par le distributeur 207 et une alarme est générée.The next step is to detect if a workpiece is absent, that is to say, if the approach cylinder 3 comes into over travel abutting against the stopper 15. In this case, the seal 7 exceeds the hole 26 which has the effect of putting the pressure switch 217 in communication with the high pressure of the chamber 17 via the connector 27 and the pipe 216. When this high pressure is detected, the cycle is interrupted, the supply of compressed air is cut by the distributor 207 and an alarm is generated.

Si la haute pression n'est pas détectée par le pressostat 217 après une durée prédéterminée, la vanne de soufflage 211 est ouverte pour souffler un rideau d'air autour du cylindre d'approche 3, et la vanne 219 de mise à l'air libre de la chambre 17 est ouverte de manière à entamer les frappes de la bouterolle par le piston 50.If the high pressure is not detected by the pressure switch 217 after a predetermined time, the blast valve 211 is opened to blow an air curtain around the approach cylinder 3, and the vent valve 219 free of the chamber 17 is opened so as to start the striking of the rivet by the piston 50.

L'étape de frappe se décompose en cycles de trois phases illustrées respectivement aux figures 22a, 22b et 22c.The typing step is broken down into cycles of three phases illustrated respectively in Figures 22a, 22b and 22c .

Dans la figure 22a, le piston 50 est en phase d'avance. La haute pression s'exerce sur la face arrière 230 du piston par l'intermédiaire de la rainure 70. La rainure 66 est à l'échappement par l'intermédiaire de la gorge annulaire 56 et des perçages 69. La valve 54 est maintenue en position arrière par la haute pression dans la rainure 70, avec l'orifice calibré 93 en appui sur le siège 62.In the figure 22a the piston 50 is in advance phase. The high pressure is exerted on the rear face 230 of the piston via the groove 70. The groove 66 is exhausted through the annular groove 56 and the holes 69. The valve 54 is held in position. rear position by the high pressure in the groove 70, with the calibrated orifice 93 resting on the seat 62.

Lorsque la face avant 231 du piston 50 dépasse les perçages 120 de l'échappement (via la chambre 17), l'air à l'avant du piston est chassé par la rainure 66, la gorge 56 et les perçages 69. Lorsque la face arrière 230 du piston dépasse les perçages 120, il se produit une dépression au niveau de ces perçages. La valve 54 qui subit la haute pression par l'orifice 93 a tendance à se déplacer vers le bas.When the front face 231 of the piston 50 exceeds the bores 120 of the exhaust (via the chamber 17), the air at the front of the piston is driven by the groove 66, the groove 56 and the holes 69. rear 230 of the piston exceeds the holes 120, there is a depression at these holes. Valve 54 which experiences high pressure through port 93 tends to move downward.

Dans la figure 22b, la valve 54 a été amenée en position avancée par la haute pression. Le piston 50 frappe la bouterolle 5 et rebondit. La rainure 65 est sous pression et la valve 54 est appuyée vers l'avant.In the figure 22b , the valve 54 was brought into the advanced position by the high pressure. The piston 50 hits the rivet 5 and bounces. Groove 65 is under pressure and valve 54 is pressed forward.

Lorsque la face arrière 230 du piston dépasse les perçages 120, il y a compression sur la valve 54 pour son retour en position arrière. La rainure 67 crée une fuite entre les rainures 70 et 65 de manière à amortir la course du piston entre les perçages 120 et la boîte à valve 55. Lorsque la face avant 231 du piston dépasse les perçages 120, il y a dépression sur cette face avant et la valve 54 revient en position arrière.When the rear face 230 of the piston exceeds the bores 120, there is compression on the valve 54 for its return to the rear position. The groove 67 creates a leak between the grooves 70 and 65 so as to damp the stroke of the piston between the bores 120 and the valve box 55. When the front face 231 of the piston exceeds the bores 120, there is depression on this face before and the valve 54 returns to the rear position.

Dans la figure 22c, lorsque la face avant 231 du piston dépasse les perçages 120, il y a dépression sur cette face. La valve 54 se déplace vers l'arrière et ferme l'admission dans la rainure 67. La rainure 66 se trouve à l'échappement. Lorsque la valve arrive en position arrière, on se retrouve au début de la première phase.In the figure 22c when the front face 231 of the piston exceeds the bores 120, there is depression on this face. The valve 54 moves backwards and closes the intake in the groove 67. The groove 66 is at the exhaust. When the valve arrives in the rear position, we end up at the beginning of the first phase.

A l'issue d'une temporisation correspondant à la durée de frappe souhaitée, le distributeur coupe l'alimentation en air comprimé du raccord 21 pour alimenter le raccord 22 par l'intermédiaire de la conduite 209. La frappe cesse et la chambre 18 est alimentée, ce qui a pour effet de repousser le cylindre d'approche 3 vers l'arrière tandis que l'air contenu dans les chambres 17 et 19 s'échappe via le raccord 24 et la vanne 219.At the end of a delay corresponding to the desired striking time, the distributor interrupts the compressed air supply of the coupling 21 to supply the connection 22 via the pipe 209. The striking stops and the chamber 18 is fed, which has the effect of pushing the approach cylinder 3 back while the air in the chambers 17 and 19 escapes via the connector 24 and the valve 219.

Le cycle est terminé lorsque le cylindre d'approche 3 est revenu à sa position rétractée et la vanne de soufflage 211 est fermée.The cycle is complete when the approach roll 3 has returned to its retracted position and the blow valve 211 is closed.

On observera que tous les capteurs nécessaires au fonctionnement du dispositif sont électropneumatiques, ce qui permet d'éviter l'utilisation de composants optiques fragiles tels que des fibres, des cellules, des lasers...It will be observed that all the sensors necessary for the operation of the device are electropneumatic, which makes it possible to avoid the use of fragile optical components such as fibers, cells, lasers, etc.

Claims (10)

  1. Pneumatic assembly for a sand removal installation for foundry cores, comprising:
    - a barrel (1) that includes means (20) for supplying compressed air and means (25) for evacuation of pulsed air;
    - a forward-travel cylinder (3) mounted so as to be able to slide in the barrel through the action of the compressed air between a withdrawn position and a working position in which a punch (5) mounted at the free end of the forward-travel cylinder is in contact with a workpiece;
    - striking means (50) for imparting, through the action of the compressed air, repeated impacts to the end of the punch opposite the end thereof in contact with the workpiece;
    characterized in that it comprises:
    - an annular chamber (29) formed in a guide and retention collar (12) mounted at the front of the barrel and connected by a perforation (30) to a connector (31) capable of being connected to a source of high-pressure air in order to create, at the location where the forward-travel cylinder penetrates the barrel, an air curtain around the forward-travel cylinder.
  2. Pneumatic assembly according to Claim 1, in which:
    - the forward-travel cylinder penetrates the barrel through a bore (28);
    - the annular chamber (29) is formed in the surface of the bore (28), separated from the free end of the bore by an annular lip (33) arranged in order to allow an escape of air between the edge of the lip and the forward-travel cylinder, and further comprise means for entraining compressed air into said chamber.
  3. Pneumatic assembly according to Claim 2, in which the barrel is hollow and, at the exit from the barrel, is affixed the guide and retention collar (12) for guiding sliding of the forward-travel cylinder, said collar including said bore.
  4. Pneumatic assembly according to any one of Claims 1 to 3, in which the blowing air is a non-lubricated air.
  5. Pneumatic assembly according to any one of Claims 1 to 4, comprising:
    - an annular chamber (35) formed in the collar (12) and connected by a perforation (36) to a connector (37) capable of being connected to the high-pressure air source and to a pressure-sensitive device; and
    - a perforation (38) formed in the wall of the forward-travel cylinder in such a manner as to open out, on the one hand, in a bore (39) of the forward-travel cylinder and, on the other, in the annular chamber (35), when the forward-travel cylinder is in its withdrawn position;
    and in that the punch (5) comprises a tail (40) that, when the punch (5) is mounted at the free end of the forward-travel cylinder (3), occupies the longitudinal location of the bore (39) of the forward-travel cylinder in which the perforation (38) opens, in such a manner that the tail of the punch blocks the perforation (38),
    in order that, by means of the pressure-sensitive device, the presence or absence, respectively, of a compressed-air supply pressure above a predetermined threshold, and thus the presence or absence, respectively, of the punch is detected when the forward-travel cylinder is within its withdrawn position and a punch is mounted on the forward-travel cylinder; and
    inhibition means (225) for inhibiting said air-supply means when the presence of the punch is not detected.
  6. Pneumatic assembly according to Claim 5, in which:
    - the mounting tail (40) is substantially cylindrical;
    - the pneumatic assembly further comprises a channel (214) for supplying said perforation with compressed air and the pressure-sensitive device (215) connected to said channel.
  7. Pneumatic assembly according to Claim 6, in which said perforation (38) in the wall of the forward-travel cylinder is connected to said channel (214) by means of a perforation (36) made in the wall of the guide and retention collar opposite the perforation in the wall of the forward-travel cylinder when the forward-travel cylinder is in the withdrawn position.
  8. Pneumatic assembly according to Claims 1 and 5 in their entirety, in which the compressed air for which the supply pressure is detected by the pressure-sensitive device (215) originates from the same source as the blowing air.
  9. Pneumatic assembly according to one of the preceding claims, in which said air curtain is a curtain of said compressed air.
  10. Sand removal installation, characterized in that it comprises a pneumatic assembly according to any one of Claims 1 to 9.
EP06778805A 2005-07-08 2006-07-06 Pneumatic assembly for a sand removal installation for foundry cores Active EP1910037B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR0507330A FR2888137B1 (en) 2005-07-08 2005-07-08 PNEUMATIC ASSEMBLY FOR DESSAVING FOUNDRY CORES
PCT/FR2006/001629 WO2007006935A1 (en) 2005-07-08 2006-07-06 Pneumatic assembly for an installation that is used for the blast cleaning of foundry cores

Publications (2)

Publication Number Publication Date
EP1910037A1 EP1910037A1 (en) 2008-04-16
EP1910037B1 true EP1910037B1 (en) 2012-11-14

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Application Number Title Priority Date Filing Date
EP06778805A Active EP1910037B1 (en) 2005-07-08 2006-07-06 Pneumatic assembly for a sand removal installation for foundry cores

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EP (1) EP1910037B1 (en)
FR (1) FR2888137B1 (en)
WO (1) WO2007006935A1 (en)

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Also Published As

Publication number Publication date
FR2888137A1 (en) 2007-01-12
WO2007006935A1 (en) 2007-01-18
FR2888137B1 (en) 2009-01-23
EP1910037A1 (en) 2008-04-16

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