GB2098896A - Apparatus for alternately moulding cope and drag moulds - Google Patents

Abstract

Two flanged conveyors (6, 18) pass one over the other on each side of and at a moulding station (2), the upper conveyor (6) carrying a pair of (cope and drag) mould boxes (8) and the lower (18) carrying a pair of patterns (22, 24), which are horizontally moved, alternately into and then out of the moulding station (2) from one side to the other. One specific improvement is the provision of separate sections (10, 20) of the respective conveyors (6, 18) at the mould station (2) which are substantially rigidly connected and lowerable as a unit to sequentially position a said mould pattern (23) over a platen (26) in the mould station (2), and a mould box (8) on the pattern (22) prior to the moulding cycle commencing. Another improvement is the provision of a coupling (30) linking patterns (22, 24) on the lower conveyor (18) which permits relative vertical movement as the pattern (22) and box (8) are located on the platen (26). A third is the provision of at least one locating mechanism (42) for positioning the respective patterns (22, 24) prior to and during the moulding cycle. A fourth, is a roller conveyor (56) on each side of the station (2), for changing a pattern, upon lowering the conveyor (18) by means of a cylinder (58) until the pattern (18) is on the rollers (56). <IMAGE>

Description

SPECIFICATION Foundry moulding machines This invention relates to apparatus for producing moulds, particularly moulds for use in foundry moulding machines. The apparatus enables the production of cope and drag moulds alternately.

Some foundry machines are adapted to receive cope and drag moulds alternately from which to form a series of completed moulds.

Generally, moulds have heretofore been produced on two separate apparatus and require arrangement before use in the machine. While attempts have been made to provide apparatus which enables cope and drag moulds to be produced alternately in a continuous process the requisite mechanism has been cumbersome and the apparatus has required more space than is readily available.

It has been proposed to support cope and drag patterns on linked carriages movable alternately into the mould-forming station synchronously with the delivery of mould boxes thereto as described in published British Patent Application Serial No: 2,021,018A and, while the machine described therein is quite satisfactory, certain problems do arise in the synchronizing of the box and pattern movements, and the location of the pattern in the mould-forming station.

The present invention seeks to mitigate the above problems and provide apparatus similar to that described in Serial No: 2,021,018A, but of simpler construction and having improved performance in various respects.

The apparatus described in Serial No: 2,021,018A defines two conveyor paths which both pass through a mould-forming station. The first passes over the second and carries mould boxes to and from the station.

The second supports two linked carriages which each support a mould pattern. At the forming station each conveyor path is defined by a section separate from the remainder of the respective path enabling the section of the second path to be lowered, whereby a mould pattern supported thereon is lodged on a platen, and the section of the first also to be lowered, enabling a box to be deposited on the pattern. When both are supported on the platen, the box is filled with sand and compacted around the pattern to form the mould.

The procedure is then reversed, both conveyor sections returning to their respective conveyor paths and the formed mould being removed along the first path. The next mould box arrives at the forming station as the patterns are switched on the second conveyor path, and the moulding cycle is repeated.

The present invention is directed at three specific improvements of the above apparatus.

In the first, the two conveyor sections are rigidly connected to one another such that their synchronous movement can be assured.

Thus, both sections are lowered together, the platen being located such that the pattern is lowered onto the platen before the empty box is deposited on the pattern. A single mechanism is thus all that is required to effect the initial step in the mould-forming operation. In the second, the carriages are linked by a coupling which permits relative vertical motion between the carriages substantially to the exclusion of relative horizontal motion. The coupling takes the form of bead and slot connection oriented vertically which enables a pattern to be lowered onto the platen without the interference of horizontal forces. In the third, a locating mechanism is provided for precisely positioning a pattern on or over the platen for careful alignment with the box to be lowered thereonto.For stability, a similar mechanism may be included for location of the pattern not in use to further stabilize the apparatus as a mould is formed. The present invention also does without separate carriages and bolsters for the mould patterns; the patterns themselves being borne on the second conveyor path.

Each improvement described above may be adopted to advantage independently or in combination. Apparatus embodying all three will now be described by way of example and with reference to the accompanying drawings wherein: Figure 1 is an elevation, partly in section, of the mould-forming station and one side section of the conveyor paths in apparatus according to the invention; Figure 2 is a section taken on line ll-ll of Fig. 1; Figure 3 is a sectional plan view taken on line Ill-Ill of Fig. 1; and Figure 4 is a perspective view of the apparatus shown in the previous Figures with the mould box and pattern excluded.

The apparatus shown in the drawings comprises a mould-forming station 2 which is flanked on either side by a framework 4. Only one framework 4 is shown to the right of the station 2; a similar framework will be provided to the left. In the framework 4 an upper delivery flanged conveyor 6 is fixed, along which empty mould boxes (8) are delivered to the station 2. To receive an empty box 8, a draw conveyor section 10 is provided at the station 2 mounted on stanchions 1 2 of a draw 1 4. The draw is supported on four hydraulic piston/cylinder mechanisms 1 6 which are operable to raise or lower the draw 14, and thereby the section 10 to or from the level of the delivery conveyor 6.

The framework 4 also supports a lower flanged pattern conveyor 1 8 which is aligned with a flanged shuttle conveyor 20 in the mould-forming station. Two mould patterns 22,24 (Fig. 2) are supported respectively on the pattern conveyor 1 8 and the shuttle con veyor 20. Beneath the draw conveyor 10 and the shuttle conveyor 20 is a stationary platen 26. The shuttle conveyor 20 is also mounted on the stanchions 1 2 of the draw 1 4 such that when the draw 14 is lowered on the mechanisms 16, the pattern 22 is lowered onto the platen 26 and as the draw 1 4 continues to lower, the box 8 is deposited over and around the pattern 22 on the platen 26.The mould-forming cycle is then carried out; the box being filled with sand and a binder and the compacting plate 28 lowered onto the sand to compact it around the pattern 22 in known manner. Throughout the mouldforming cycle, the pattern 22 and box 8 are supported only on the platen 26, the flanged conveyors 10 and 20 being located respectively below the box 8 and pattern 22, as shown in Fig. 1. When the mould-forming cycle is complete, the draw 14 is raised on the mechanisms 16, returning the draw conveyor 10 to the level of the delivery conveyor 6, and the shuttle conveyor 20 to the level of the pattern conveyor 1 8. The box 8 with mould is carried away to the left on a framework not shown in the drawing, and a fresh, unfilled mould delivered to the station 2 along delivery conveyor 6.The mould-forming cycle can then be repeated to produce a subsequent mould from the same pattern 22, but in order to produce alternate cope and drag moulds, the pattern 22 (cope) is switched with pattern 24 (drag) by the mechanism described below.

With the shuttle conveyor 20 aligned with the pattern conveyor 18 in the framework 4, and with a similar conveyor in the framework (not shown) to the left of the station 2, a continuous conveyor path is defined which extends through the station 2. The patterns 22, 24 are connected by a coupling 30 and are shifted in tandem by means of an hydraulic piston/cylinder mechanism 32 to move the pattern 22 to the left as shown and locate the pattern 24 over the platen 26. This shifting can be accomplished simultaneously with the delivery of an empty box 8 to the draw conveyor 10 such that there is no necessity for delay before the next mould-forming cycle can commence. With the completion of this cycle, the mechanism 32 is again operated and the patterns 22,24 returned to their positions shown in Fig. 2.

The coupling 30 comprises a convex forked cross-section vertical groove 34 formed in a member 36 mounted on pattern 22, and a bead 38 formed on a member 40 mounted on pattern 24. The groove 34 and bead 38 have sufficient vertical length to permit one pattern (22) to lower relative to the other (24), during a mould-forming cycle, onto the platen 26 without the patterns becoming wholly disconnected. In order to ensure that a) the pattern 22 or 24 is properly located over the platen 26, and b) that the coupling 30 will not interfere with its lowering thereonto, locating means 42 are provided. These means comprise a groove 44 formed in the side of the patterns 22,24 into which an arm 46 of a bell crank 48 engages. The sides of the groove 44 are bevelled such that engagement by the arm 46 can finally adjust the position of the pattern 22 before it is lowered onto the platen 26.The area 46 may remain engaged throughout the moulding cycle, but is normally withdrawn before the draw 14 is lowered. As shown, the crank 48 is operated by means of an hydraulic piston cylinder mechanism 50 fixed in the station 2. Two or more locating mechanism may be used on either side of the pattern (22) in the station 2, and similar means may be employed for the pattern (24) on the pattern conveyor 1 8 as indicated to further stabilize the assembly during the mould-forming cycle.

As noted above, each of the conveyors 10,20 is a flanged conveyor comprising a plurality of rollers 52 on frame members on either side of the respective paths. This enables the lateral dimension of each conveyor to be adjusted without difficulty to suit mould boxes 8 and patterns 22,24 of different sizes, and the boxes 8 and patterns 22,24 to be supported directly on the conveyors without the need for separate carriages, although these may of course still be used. It also enables the draw to lower around the platen 26 to drop the pattern 22 and then the box 8 thereonto. The lateral spacing of the rollers 52 on the lower conveyors 1 8 and 20 is normally less than that of the upper conveyors 6 and 10, to minimize the risk of the draw conveyor section 10 interfering with a pattern 22 on the platen 26 when the draw is in motion.

The construction of the moulding station can thus be relatively simple and involve only a minimal number of moving parts.

According to the invention, provision is also made for facilitating a change of pattern. In the framework 4, the pattern conveyor 18 (also flanged) is itself supported on a lowerable frame 54. Into the framework 4 extends a roller conveyor 56 beneath the pattern conveyor 1 8. To change the pattern 24, the conveyor 1 8 is lowered on an hydraulic piston/cylinder mechanism 58 to drop the pattern 24 onto the roller conveyor 56. With the coupling 30 disconnected, the pattern 24 can be withdrawn on the roller conveyor 56 and replaced. The other pattern 22 can be replaced using a similar mechanism in the framework to the left of the forming station 2, or sequentially along the conveyor 56 in the framework 4.

Claims (14)

1. Apparatus for producing moulds comprising a mould forming station with a platen; a first conveyor for carrying mould boxes to and from the station; a second conveyor passing below the first conveyor, but over the platen, at the station for supporting two linked patterns; and means for horizontally reciprocating such linked patterns on the second conveyor to alternately position such patterns at the mould station, wherein sections of the conveyors at the station are formed separately from the remainder of the respective conveyors and are vertically movable relative thereto, the sections being rigidly connected to one another whereby they are lowerable simulta neously to sequentially position a said mould pattern over the platen, and a said mould box on said pattern, means being provided for effecting reciprocal vertical motion of the conveyor sections.

2. Apparatus according to Claim 1 wherein said sections are mounted on com mon stanchions to form a substantially rigid frame, the apparatus including hydraulic means for raising and lowering the frame.

3. Apparatus according to Claim 1 or Claim 2 wherein the respective conveyor sections comprise flanged conveyors with rollers on either side thereof, the lateral spacing of the sides of each section being adjustable.

4. Apparatus for producing moulds comprising a mould forming station with a platen; a first conveyor for carrying mould boxes to and from the station; a second conveyor passing below the first conveyor, but over the platen, at the station for supporting two linked patterns; and means for horizontally reciprocating such linked patterns on the second conveyor to alternately position such patterns at the mould station, wherein sections of the conveyors at the station are formed separately from the remainder of the respective conveyors and are vertically movable relative thereto, means being provided for effecting reciprocal vertical movement of the conveyor sections whereby the sections are lowerable to sequentially position a said mould pattern over the platen, and a said mould box on said pattern, means being provided for linking two said patterns on the second conveyor by means of a coupling which permits relative vertical movement therebetween substantially to the exclusion of relative horizontal motion.

5. Apparatus according to Claim 4 wherein the coupling comprises a convex forked cross-section vertical groove on one part thereof, and a bead on the other, the vertical extent of the coupling being sufficient to accommodate the lowering of a said pattern onto the platen without the linkage being lost.

6. Apparatus according to Claim 4 or Claim 5 including means for linking one of said patterns to the reciprocating means by a coupling which permits relative vertical movement therebetween substantially to the exclusion of relative horizontal motion.

7. Apparatus for producing moulds comprising a mould forming station with a platen; a first conveyor for carrying mould boxes to and from the station; a second conveyor passing below the first conveyor, but over the platen, at the station for supporting two linked patterns; and means for horizontally reciprocating such linked patterns on the second conveyor to alternately position such patterns at the mould station, wherein sections of the conveyors at the station are formed separately from the remainder of the respective conveyors and are vertically movable relative thereto, means being provided for effecting reciprocal vertical movement of the conveyor sections whereby the sections are lowerable to sequentially position a said mould pattern over the platen, and a said mould box on said pattern, the apparatus including at least one locating mechanism for accurately positioning a said pattern horizontally in the mould forming station with respect to the platen.

8. Apparatus according to Claim 7 including an additional locating mechanism for horizontally positioning the other of said linked patterns.

9. Apparatus according to Claim 7 or Claim 8 in which the or each locating mechanism does not substantially inhibit vertical movement.

1 0. Apparatus according to any of Claims 7 to 9 wherein the or each mechanism comprises a bell crank of which one arm is coupled to a drive device and the other is adapted to engage a groove defined with respect to a said pattern.

11. Apparatus according to Claim 10 wherein the sides of the groove are bevelled.

1 2. Apparatus according to any preceding Claim including two carriages supported on the second conveyor, each carriage being adapted to support a said pattern, to rest on the platen and support a platen thereover when the conveyor sections are lowered as aforesaid.

1 3. Apparatus according to Claim 4 and Claim 1 2 wherein the coupling is between the carriages.

14. Apparatus according to Claim 7 and Claim 1 2 wherein the or each locating mechanism acts on a carriage.

1 5. Apparatus for producing moulds comprising a mould forming station with a platen; a first conveyor for carrying mould boxes to and from the station; a second conveyor passing below the first conveyor, but over the platen, at the station for supporting two linked patterns; and means for horizontally reciprocating such linked patterns on the second conveyor to alternately position such patterns at the mould station, wherein sections of the conveyors at the station are formed separately from the remainder of the respective conveyors and are vertically movable relative thereto, means being provided for effecting reciprocal vertical movement of the conveyor sections whereby the sections are lowerable to sequentially position a said mould pattern over the platen, and a said mould box on said pattern, including a pattern change conveyor extending below the second conveyor outside the mould forming station, a further section of the second conveyor being selectively lowerable to permit transfer of mould patterns to and from the second conveyor.

1 6. Apparatus for producing moulds substantially as described herein with reference to the accompanying drawings.