EP0018232A1 - Vorrichtung zum Wenden einer Sandform - Google Patents

Vorrichtung zum Wenden einer Sandform Download PDF

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Publication number
EP0018232A1
EP0018232A1 EP80301293A EP80301293A EP0018232A1 EP 0018232 A1 EP0018232 A1 EP 0018232A1 EP 80301293 A EP80301293 A EP 80301293A EP 80301293 A EP80301293 A EP 80301293A EP 0018232 A1 EP0018232 A1 EP 0018232A1
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EP
European Patent Office
Prior art keywords
mold
jaws
frame
rollers
jaw
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP80301293A
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English (en)
French (fr)
Inventor
Earl W. Powers
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
DEPENDABLE-FORDATH Inc
Dependable Fordath Inc
Original Assignee
DEPENDABLE-FORDATH Inc
Dependable Fordath Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by DEPENDABLE-FORDATH Inc, Dependable Fordath Inc filed Critical DEPENDABLE-FORDATH Inc
Publication of EP0018232A1 publication Critical patent/EP0018232A1/de
Ceased legal-status Critical Current

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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
    • B22D33/00—Equipment for handling moulds
    • B22D33/02—Turning or transposing moulds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C17/00—Moulding machines characterised by the mechanism for separating the pattern from the mould or for turning over the flask or the pattern plate

Definitions

  • the present invention relates to apparatus for inverting sand molds. More particularly it concerns roll over draw and close apparatuses adapted to be incorporated into a multi-station assembly line apparatus for producing a continuous succession of joined cope and drag sand mold portions for foundry use.
  • Multi-station sand mold making apparatuses have been known heretofore. It is desirable that such apparatuses be capable of simultaneously producing the cope (upper half) and drag (lower half) portions of a composite sand mold, the two portions being complete and assembled upon each other and ready for the molten metal pouring operation at the time they leave the apparatus.
  • a plurality of mold boxes each containing a mold pattern, are circulated around a closed pathway through a succession of stations at which different mold making operations are performed. Each mold box forms either a cope half or a drag half of a completed sand mold.
  • a predetermined amount of sand containing a binder and a catalyst is poured into an open-top mold box containing a pattern.
  • the mold box is simultaneously vibrated to eliminate voids and produce some compaction of the sand.
  • the amount of sand which is poured into the mold box is sufficient to form a mound which extends above the upper edges of the box.
  • the sand is distributed, levelled, and slightly compacted before the binder hardens. This may be done by hand tamping, by using a ramming apparatus, by using revolving rollers, or by some other known technique.
  • a bottom board is either manually placed or automatically fed onto the top of the mold box. Thereafter at the same station or at a succeeding station the mold box and bottom board are clamped together from above and below and inverted. The mold box is then vibrated and the now hardened cope or drag mold portion is stripped or "drawn" from the mold box and then removed from the bottom board.
  • Cope and drag halves produced in this manner may be joined or "closed" manually to form a composite sand mold which is then sent to a molten metal pouring station.
  • mechanical lifting devices often need to be employed.
  • An efficient automated system capable of realizing the potential mold production rates made possible by the no-bake sand/resin binder process requires the ultilization of automatic, relatively rapid draw and close apparatuses. Such apparatuses must operate with precision and must be designed to minimize the scrap rate attributable to mold breakage.
  • apparatus for inverting a sand mold comprising: means for receiving the mold and supporting the same for rotational movement; means for rotating the receiving and supporting means to invert the mold during a predetermined time interval; and means for regulating the rate of the rotation to substantially minimize the forces exerted on the internal structure of the mold and prevent fracturing of the same.
  • the sand mould inverting apparatus for example an in-line roll over draw or close apparatus, receives the mold from and discharges it onto the same conveying line into which the apparatus is installed and the rotating means which control the rotation of the sand mould cause the mold to be smoothly inverted thus minimizing the frequency of breakages.
  • automatic control means enable the rapid production of a continous succession of joined cope and drag sand mold halves ready for a molten metal pouring operation.
  • the inverting apparatus is capable of accommodating a wide range of loads.
  • a mixer apparatus 10 a strike off apparatus 12,- a bottom board feeder apparatus 14, a roll over draw apparatus 16 constructed in accordance with the present invention, and a roll over close apparatus 18 constructed in accordance with the present invention are stationed successively along a pathway or main conveying line 20 of intermittently powered conveying rollers.
  • Each mold box contains a pattern such as indicated at 24.
  • a cope portion of a mold will first be described.
  • a pneumatic cylinder 28 pushes the mold box beneath the discharge end 30 of the mixer 10.
  • a predetermined amount of sand 32 containing a resin binder and a catalyst is automatically poured into the mold box ( Figure 2A, step A).
  • the mold box is simultaneously vibrated to eliminate voids and produce some compaction of the sand.
  • the amount of sand which is poured into the mold box is sufficient to form a mound which extends above the upper edges of the box.
  • One suitable mixer is disclosed in co-pending U.S. Patent Application Serial No. 22,609 filed March 21, 1979.
  • Each mold box may have a metal strip affixed to its underside.
  • the location of the strip serves as an indicator of the volume of the mold box.
  • the location of the strip is sensed by a proximity sensor in order to determine the quantity of sand which is to be poured into the mold box.
  • the mold box 22 containing the mound of sand 32 is conveyed to a corner 34 of the main conveying line 20 where it momentarily stops. After a time delay, the mold box 22 leaves the corner 34 and travels toward the strike off apparatus 12.
  • An infrared proximity sensor 36 mounted on an assembly supporting a pair of rollers 38, is activated. At this point the rollers 38 are at their upper limit of movement and an elevating mechanism lowers the roller assembly, and the sensor 36 until its horizontal scanning beam is intercepted by the mound of sand 32 in the mold box. This is done before the box reaches the rollers.
  • the rollers 38 stop at a height so that they ride over the sand in the mold box as the box passes thereunder ( Figure 2A, step B).
  • the sand is levelled and slightly compacted by the rollers. After the mold box has passed under the rollers they are raised to their original positions and the strike off apparatus awaits the next succeeding box.
  • the details of the strike off apparatus 12 are disclosed in co-pending U.S. Patent Application Serial No. 967,110 filed December 6, 1978.
  • the mold box 22 is conveyed along the pathway 20 to the bottom board feeder apparatus 14 where it momentarily stops in position for receiving a bottom board such as 40.
  • An infrared proximity sensor 42 mounted on the board elevating mechanism of the bottom board feeder apparatus senses the presence of the mold box 22.
  • the bottom board 40 has already been conveyed along a return conveying line 44 of intermittently powered conveying onto the bottom board feeder apparatus 14.
  • the elevating mechanism of the bottom board feeder apparatus raises the bottom board 40 until the horizontal scanning beam of the sensor 42 is above the upper surface of the mold box 22.
  • a shuttle mechanism 46 of the bottom board feeder apparatus feeds the bottom board laterally onto the top of the mold box ( Figure 2A, step C).
  • the details of the bottom board feeder apparatus 14 are disclosed in co-pending U.S. Patent Application Serial No. 966,254 filed December 4, 1978.
  • the mold box 22, now covered with a bottom board 40 is conveyed along the main conveying line 20 to the roll over draw apparatus 16.
  • the mold box 22 and the bottom board 40 are clamped between jaws of rollers 48 and arms 50 grip the bottom flange of the mold box ( Figure 2A, step D).
  • the mold box 22 and the bottom board 40 are inverted, i.e. rolled over 180 degrees ( Figure 2A, step E).
  • the now hardened cope portion 52 of the sand mold is lowered out of the mold box 22 with the aid of vibrating mechanisms by unclamping the jaws of rollers 48 ( Figure 2A, step F).
  • the cope portion 52 and the bottom board 40 upon which it now rests are conveyed out of the roll over draw apparatus 16 and along the main conveying line 20 to the roll over close apparatus 18.
  • the mold box 22 is clamped between the rollers 48 and re-inverted, i.e. rolled over 180 degrees.
  • the mold box 22 is then conveyed out of the roll over draw apparatus 16 to a box return mechanism 54 positioned between the roll over draw apparatus 16 and the roll over close apparatus 18.
  • the mechanism 54 ejects the mold box 22 laterally and the mold box is returned along the main conveying line 20 to its original starting place.
  • Arms 56 of the roll over close apparatus 18 clamp the cope portion 52 and raise it off the bottom board 40 ( Figure 2A, steps G and H).
  • the bottom board 40 is conveyed out of the roll over close apparatus 18 to a position adjacent a pneumatic cylinder 58 which pushes the board laterally to a position adjacent a pneumatic cylinder 60.
  • the cope portion 52 is inverted, i.e. rolled over 180 degrees ( Figure 2A, step I).
  • the cope portion 52 is maintained in an elevated position above the level of the main conveying line 20 awaiting the arrival of a drag portion.
  • the multi-station sand mold making apparatus shown in Figure 1 produces the drag portion 62 of the composite sand mold (Figure 2B, step J), the steps being the same as steps A through F ( Figure 2A).
  • the drag portion 62 and the bottom board 64 upon which it rests are then conveyed into the roll over close apparatus 1.8 directly underneath the waiting cope portion 52 ( Figure 2B, step K).
  • the cope and drag portions 52 and 62 are joined ( Figure 2B, step L) and they are conveyed, resting on top of the bottom board 64, out of the roll over close apparatus 18 to a position adjacent the pneumatic cylinder 58.
  • the pneumatic cylinder 58 pushes the bottom board 64, and the cope and drag portions 52 and 62 carried thereby, laterally to a position adjacent the pneumatic cylinder 60.
  • the bottom board 64 pushes the bottom board 40 onto the return conveying line 44 and the powered conveying rollers thereof convey the bottom board 40 back to the bottom board feeder apparatus 14.
  • An infrared proximity sensor 66 senses the presence of the completed sand mold and actuates the pneumatic cylinder 60 which pushes the joined cope and drag portions 52 and 62 . down a chute 68 which leads to a metal pouring station ( Figure 2B, step M).
  • the next succeeding bottom board that is pushed laterally by the pneumatic cylinder 58 will push the bottom board 64 laterally onto the return conveying line 44 which will return it to the bottom board feeder apparatus 14.
  • the roll over draw apparatus 16 includes a base or stand l02 made of steel box beams which are welded together to form a rigid supporting structure.
  • Upper and lower jaws l04 and 106 each having a plurality of rollers 48 are supported in opposing relationship by a generally rectangular vertical frame 108 rotatably mounted on the stand 102.
  • a hydraulic engine in the form of a rotary actuator 110 rotates the vertical frame 108 and the jaws 104 and 106 about a horizontal axis as indicated by the arrows.
  • the roll over draw apparatus 16 is designed to be inserted into a gap in the main conveying line 20 so that the rollers 48 of either its upper jaw 104 or its lower jaw 106 will form a continuation of the main conveying line.
  • the axis of rotation of the vertical frame 108 and of the upper and lower jaws 104 and 106 extends transverse to the main conveying line 20.
  • transverse refers to the direction perpendicular to the line of travel of the mold boxes down the main conveying line 20.
  • longitudinal refers to the direction of extension of the main conveying line.
  • the forward end of the roll over draw apparatus is that portion viewed along the line 4-4 of Figure 3.
  • the rearward end of the apparatus is that portion which includes the stand 102.
  • a sand mold which is transported toward the roll over draw apparatus 16 by powered conveying rollers of the main conveying line 20 will be received on the rollers 48 of the lower jaw 106 of the apparatus. After being inverted by 180 degree rotation of the vertical frame 108 the mold will be discharged from the rollers 48 of the upper jaw 104 back onto the main conveying line 20.
  • the roll over draw apparatus in thus an "in-line" apparatus in the sense that it receives from and discharges onto the same conveying line into which it is installed. It is thus more compact than other roll over draw apparatuses which rotate in a plane transverse to the main conveying line.
  • the stand 102 has a pair of legs 112 ( Figures 3, 4 and 5) which rest on the floor and extend transversely underneath the main conveying line 20.
  • the legs 112 are connected by a cross beam 114 ( Figure 4).
  • a pair of vertically extending beams 116 ( Figure 3) are welded at their lower ends to the cross beam 114 and are supported from the side by inclined beams 118 ( Figure 4).
  • Front and back steel mounting plates 120 and 122 ( Figure 3) are welded to opposite sides of the upper portions of the vertical beams 116.
  • a pair of rearwardly extending inclined beams 116 are welded to opposite sides of the upper portions of the vertical beams 116.
  • a pair of rearwardly extending inclined beams 124 are welded at their upper ends to the back mounting plate 122 and at their lower ends to a pair of rearwardly extending horizontal legs 126 welded to the cross beam 114 of the stand 102.
  • Triangular braces such as 128 are welded to adjoining beams in various locations to further strengthen the stand 102.
  • the stand 102 By constructing the stand 102 in the above described manner a rigid supporting structure is provided to support the jaws 104 and 106 and the frame 108 for rotational movement.
  • the stand 102 must be capable of supporting loads of several thousand pounds.
  • the legs 112 must be spaced far enough apart to prevent the stand 102 from tipping about the axis of rotation of the jaws when the rotational load is substantially off centre and unbalanced.
  • the legs 112 and 126 must extend a sufficient distance in a transverse direction. Otherwise, the stand 102 may tip forwardly or backwardly when relatively heavy sand molds are conveyed onto the lower jaw 106 and thereafter off of the upper jaw 104.
  • the vertical frame 108 which supports the upper and lower jaws 104 and 106 includes a pair of vertically extending, inwardly facing channel beams 130. These beams are welded at their upper and lower ends to a pair of horizontally extending outwardly facing channel beams 132.
  • a relatively large, vertically extending bearing plate 134 is welded to the rearward flanges 136 of the vertical channel beams 130.
  • a large ring-type bearing 138 is bolted to the bearing plate 134 and to the front mounting plate 120 of the stand 102.
  • the hydraulic rotary actuator 110 is rigidly secured to the back mounting plate 122 of the stand 102.
  • One suitable hydraulic rotary actuator is manufactured by FLO-TORK, INC. Orville, Ohio, 44667 and is sold under the registered trademark FLO-TORK. It is manufactured under U.S. Patent Nos. 2,844,127; 2,844,128; and 3,246,581.
  • This actuator has two pairs of opposing hydraulic cylinders. They move upper and lower rack gears which engage a pinion gear on its output shaft to rotate the same.
  • This actuator is available with a wide range of operating pressures and torques. It is a positive displacement hydraulic engine capable of precise positioning of substantial loads.
  • the cylinder heads serve as positive internal stops and may be provided with cushions to absorb some of the shock at each end of the rotation when the pistons contact the cylinder heads.
  • the output shaft of the rotary actuator 110 extends through a hole in the back mounting plate 122 and is coupled to the rearward end of a drive shaft (not visible in the drawings).
  • the drive shaft extends through a coupling 140 and through the bearing 138. Its forward end is rigidly secured to the bearing plate 134.
  • Not shown in the drawings are the various hydraulic hoses, pneumatic hoses, and electrical cables which supply power to the various actuating components mounted on the jaws. Hydraulic fluid, pressurized air, and electrical current must be supplied to these "on board" actuating components.
  • rotatable connections are made through or near the centre of rotation of the vertical fram 108 via the coupling 140.
  • One suitable coupling includes manifold and slip-ring assemblies.
  • the hydraulic rotary actuator 110 shown in phantom lines rotates the vertical fram 108 180 degrees in a counter-clockwise direction indicated by the arrow to invert a mold contained within a mold box.
  • the lower jaw 106 will be at the top of the apparatus and the upper jaw 104 will be at the bottom thereof.
  • the vertical frame 108 will be re-inverted, i.e. rotated back to its original position in a clockwise direction.
  • the vertical frame 108 and the upper and lower jaws 104 and 106 do not rotate through a complete revolution.
  • the base or lower portion of the stand 102 has a stop assembly 150 welded thereto. It includes a rubber air bag 152 which is filled with air ambient- pressure. When the vertical frame 108 and the jaws are re-inverted a resilient pad 154 overlying the lower portion of one of the vertical channel beams 130 of the frame 108 will strike the air bag 152.
  • the air bag 152 has an orifice through which air is expelled when it is compressed.
  • the air bag 152 serves as an auxiliary cushion to prevent rotation of the vertical frame 108 past its " upright starting position.
  • the roll over draw apparatus 16 includes hydraulic circuit elements which cause the vertical frame 108 and the upper and lower jaws 104 and 106 to start and stop their rotation smoothly.
  • the gradual starting and stopping of rotational movement prevents fracturing of the mold.
  • the hardened sand molds have considerable compressive strength, their flexure strength is relatively small. These sand molds will crack or fracture as a result of their own inertia if they are accelerated or stopped too quickly. A sand mold which has been fractured or cracked is unsuitable for the molten metal pouring operation since it will produce unacceptable castings.
  • the lower jaw 106 is rigidly secured to the vertical frame 108.
  • the upper jaw 104 is supported on the frame 108 for vertical movement toward and away from the lower jaw 106.
  • the upper jaw will automatically be lowered so that the mold is clamped between the rollers 48 of the upper and lower jaws.
  • a lowered position of the upper jaw 104 is shown in phantom lines in Figure 4.
  • each jaw includes a generally square horizontal frame made of a pair of longitudinally extending beams 156 which are welded to the opposite ends of a pair of transversely extending cross pieces 158.
  • Triangular braces 159 are welded at the junctions between the beams 156 and the cross pieces 158 to further strengthen the square frames.
  • the cross pieces 158 and the rearward beam 156 of the lower jaw 106 are rigidly welded to the lower portions of the vertical channel beams 130 of the vertical frame 108 (See Figures 4 and 5).
  • the upper jaw 104 is mounted to a carriage generally designated 160 ( Figure 4) which is adapted to travel upwardly and downwardly between the vertical channel beams 130 of the vertical frame 108 for raising and lowering the upper jaw.
  • the carriage 160 includes a vertical panel 162.
  • the side edges of the panel 162 are welded to transversely extending brackets 163.
  • the forward edges of the brackets 163 are welded to the cross pieces 158 of the upper jaw 104.
  • the brackets 163 have an assembly of wheels and rollers which are adapted to travel in the channels of the channel beams 130.
  • each of the vertical channel beams 130 is provided with an inwardly projecting rail 164 which extends intermediate the channel along the entire length thereof. Secured to the inner bottom surface of the channel beam 130 on opposite sides of the rail 164 are a pair of wear strips 166.
  • each bracket 163 on either side of the carriage 160 mounted to each bracket 163 on either side of the carriage 160 are a plurality of pairs of wheels 168 and a plurality of pairs of rollers 170.
  • the axis of rotation of the wheels 168 is perpendicular to that of the rollers 170.
  • each of the brackets 163 of the carriage 160 has three vertically spaced pairs of wheels 168 and four vertically spaced pairs of rollers 170.
  • the wheels 168 engage and roll along the wear strips 166 mounted in the channel beams 130.
  • the rollers 170 engage and roll along opposite sides of the rail 164 secured to the channel beams 130.
  • the wheels 168 are rotatably supported by U-shaped housings 172 secured to the brackets 163.
  • the rollers 170 are each rotatably journalled on pins (not visible in the drawings) eccentrically positioned on the heads of bolts 174 secured through corresponding holes in the brackets 163.
  • the upper jaw 104 is movably supported on the vertical frame 108 and may be acted upon by relatively great forces without inhibiting the ability of the upper jaw to travel upwardly and downwardly along the vertical frame.
  • the rail 164 and the wear strips 166 are made of case hardened steel and are secured at their ends to the channel beams 130 by bolt assemblies so that they can be readily replaced when worn.
  • the wheels 168 and the rollers 170 are also made of case hardened steel so that they can resist wear. The wheels and rollers are mounted so that they can be readily replaced when worn. By rotating the eccentric pin/bolts 174 the clearance between the rollers 170 and the rail 164 can be adjusted.
  • the lower periphery of the panel 162 of the carriage 160 has a V-shaped cut out portion 176.
  • the piston rod 178 of a vertically extending hydraulic cylinder 180 (see Figures 4 and 5) is connected to the lower periphery of the panel 162 intermediate its width.
  • the base of the hydraulic cylinder 180 is secured to the lower channel beam 132 of the vertical frame 108.
  • the hydraulic cylinder 180 can be actuated to raise and lower the upper jaw 104 as illustrated in phantom lines in Figures 4 and 5.
  • the upper and lower jaws 104 and 106 support a plurality of transversely extending powered rollers 48. As shown in Figure 3, the forward ends of the rollers 48 are rotatably journalled in longitudinally extending angle beams 182 secured to the inwardly facing surfaces of the beams 156 of the square frames of the upper and lower jaws.
  • the rearward ends of the rollers 48 are rotatably journalled inside rectangular housings 184 secured to the inwardly facing surfaces of the rearward beams 156 of the r upper and lower jaws. See also Figure 5.
  • the rollers 48 of the upper and lower jaws are simultaneously rotated in the same direction by a drive mechanism not fully illustrated in the drawings.
  • the rearward ends of the rollers 48 are each provided with a pair of sprockets and a series of endless chains are trained around adjacent sprockets so that the rollers 48 can be simultaneously driven by rotating one of the intermediate rollers.
  • hydraulic motors 186 and 188 shown in phantom lines are mounted to the upper and lower jaws, respectively, and are each drivingly coupled with an intermediate rollers 48.
  • Suitable driven roller assemblies are manufactured by American Manufacturing Company, Inc., 2119 Pacific Avenue, P 0 Box 1237, Tacoma, Washington, 98401. They have variable speed hydraulically driven rollers which are designed to provide maximum torque throughout their speed range.
  • the lower jaw 106 is provided with means for gripping the bottom flange of a mold box. This permits a mold box to be held rigidly in position on the lower jaw 106 so that the same can be inverted and re-inverted through rotation of the vertical frame 108.
  • a mold box consists of four side walls and a bottom wall which extends beyond each of the side edges to provide a flange which can be readily gripped by a mechanical arm.
  • the lower jaw 106 has forward and rearward spaced apart pairs of vertical arms 190 and 192 which are adapted to grip the flange of a mold box.
  • the vertical arms 190 and 192 extend between adjacent rollers 48 of the lower jaw 106 and they are spaced relatively closely to the midpoint of the jaw.
  • each vertical arm 190, 192 extends slightly above the upper peripheries of the rollers 48 and has a detent 194 for receiving the flange of the mold box.
  • the lower ends of the rearward vertical arms 192 are welded to a longitundi- nally extending support member 196 whose opposite ends are welded to the cross pieces 158.
  • the forward vertical arms 190 are mounted for reciprocal movement toward and away from the rearward vertical arms 192 so that mold boxes of different sizes can be accommodated.
  • the lower ends of the forward vertical arms 190 are welded to the top of a dolly 198.
  • the dolly has side wheels 200 which travel along the lower flanges of a pair of transversely extending, inwardly facing channel beams 202. These beams are welded to the inner surfaces of the cross pieces 158 of the lower jaw 106.
  • the dolly 198 carrying the vertical arms 190 is moved toward and away from the rearward vertical arms 192 by the piston rod 204 ( Figure 5) of a horizontally extending pneumatic cylinder 206.
  • the base of the cylinder 206 is secured to a support member 208 welded at its opposite ends to the cross pieces 158 of the lower jaw.
  • the vertical arms 190 can be rapidly moved into gripping relationship with the flange of a mold box resting on the lower jaw 106 by actuation of the pneumatic cylinder 206. Thereafter, the mold box containing the sand mold is inverted.
  • the upper jaw 104 now underneath the mold box
  • the mold box will remain suspended from the lower jaw 106 as a result of the gripping action of the vertical arms 190 and 192.
  • the sand mold, resting on the bottom board, is conveyed off the rollers of the lower jaw 104 onto the main conveying line 20 toward the roll over close apparatus 18.
  • the vertical frame 108 and the jaws 104 and 106 are re-inverted.
  • the pneumatic cylinder 206 is then actuated to cause the piston rod 204 thereof to extend so that the flange of the mold box will no longer be held in gripping relationship between the forward and rearward vertical arms 190 and 192.
  • the rollers 48 of the lower jaw 106 are thereafter rotated the mold box will be conveyed back onto the main conveying line 20.
  • the lower jaw 106 further includes means for ⁇ imparting vibratory movement to the mold box to facilitate the drawing of the sand mold therefrom.
  • a pair of vertical, inverted U-shaped vibrating frames 210 extend vertically between pairs of the rollers 48.
  • the vibrating frame 210 are welded at their lower ends to a horizontal plate 211 which is in turn supported at its four corners by four rubber air bags 212.
  • the air bags are mounted on a pair of spaced apart longitudinally extending channel beams 214 which are welded at their opposite ends to the cross pieces 158 of the lower jaw 106.
  • Bolted to the underside of the plate 211 is a hammer-style, linear air driven vibrator 216 ( Figure 5).
  • the air bags 212 are in their deflated condition.
  • the upper surfaces of the vibrating frames 210 are below the upper peripheries of the rollers 48 and the vibrating frames 210 are not in contact with the bottom wall of the mold box. T he vibrator 216 is not in operation at this time.
  • the air bags 212 are inflated to move the frames 210 into engagement with the bottom wall of the mold box.
  • the vibrator 216 is actuated so that rapid vibratory movement is imparted to the mold box.
  • the jaw 104 is lowered the vibratory motion facilitates the drawing of the sand mold out of the mold box. It eliminates any adhesion between the hardened sand mold and the walls of the mold box. It also reduces the friction of the sliding engagement between the sand mold and the walls of the mold box.
  • the vibrator 216 is de-energized, and the air bags 212 are deflated.
  • the vibrating frames 210 will no longer be in engagement with the bottom wall of the mold box so that the same can be freely ejected from the lower jaw 106.
  • pressurized air is supplied through the rotary coupling 140 to a manifold 218 mounted on the lower jaw 106.
  • the pneumatic cylinder 206, the air bags 212, and the vibrator 216 are each operatively coupled through hoses and through solenoid actuated valves to the manifold 118 for receiving pressurized air from the same upon demand.
  • the pneumatic cylinder 206 is connected to the manifold 218 through a spring biased, solenoid actuated flow reversing valve 220.
  • a spring biased, solenoid actuated flow reversing valve 220 When the valve 220 is in the position shown, pressurized air will flow into the pneumatic cylinder 206 to cause its piston rod 204 to extend. This maintains the forward vertical flange gripping arms 190 in their forwardmost positions shown in sold lines in Figure 5.
  • the piston rod 204 of the pneumatic cylinder 206 will retract. This will cause the vertical flange gripping arms 190 to move in the direction indicated by the arrow in Figure 5.
  • the air bags 212 are operatively connected through hoses and through a solenoid actuated on-off valve 222 to the manifold 218.
  • the valve 222 When the valve 222 is de-energized, pressurized air will not flow into the air bags 212 and the vibrating frames 210 will remain in their lowered positions.
  • the valve 222 When the valve 222 is energized, it will shift to its on position causing pressurized air to be delivered to the air bags 212. This will inflate the air bags and move the vibrating frames 210 so that they will engage the bottom wall of the mold box.
  • the vibrator 216 is operatively connected to the manifold 218 through a solenoid actuated on-off valve 224.
  • the valve 224 is shown in its de-energized off position in which pressurized air is not delivered to the vibrator 216. When the valve 224 is energized, it will shift to its on position and pressurized air will be delivered to the vibrator 216 causing the same to impart vibratory motion to the mold box gripped between the vertical arms 190 and 192.
  • the roll over draw apparatus 16 of the present invention includes means for controlling the rate of rotation of the upper and lower jaws and the vertical frame which supports the same. Mold boxes of various sizes are conveyed onto the lower jaw 106. For example, one mold box may measure forty inches by fifty inches by seventeen inches, while the mold box following the same may measure ten inches by ten inches by twelve inches. The combined weight of a mold box and the hardened sand mold contained therein may range from less than one hundred pounds to several thousand pounds. Referring to Figure 4, it can be seen that the centre of mass of a mold box and sand mold clamped between the upper and lower jaws will in most cases be offset from the axis X of rotation of the vertical frame 108 and the upper and lower jaws 104 and 106.
  • the air bag 152 only operates when the vertical frame 108 is re-inverted, and even then it is only an auxiliary cushion which does not perform a significant amount of deceleration. It should also be noted at this point that the outer corners of the vertical frame 108 are angled or bevelled so that they will clear the air bag 152 on the stop 150 during the upswing or inversion of the frame 108. Likewise, the outer corners of the upper and lower jaws 104 and 106 are bevelled or angled so that they will clear the adjacent portions of the main conveying line 20.
  • the mold box After the sand mold has been drawn from the mold box and ejected from the roll over draw apparatus 16, the mold box must be re-inverted. Without the rotation controlling means of the present invention as soon as the vertical frame began to swing clockwise the off centre weight of the mold box would combine with the forces imparted by the rotary actuator. This would cause the vertical frame and jaws to rotate faster and faster as they approached their initial starting positions. Therefore, some means must be * incorporated into the apparatus to prevent the re-inversion or swinging down from taking place too rapidly. Without some adequate mechanism for gradually bringing the vertical frame and the jaws to rest again in their initial positions, the mold box may be jarred loose or damaged. In any case, damage to the machine itself may occur if the roll up or roll down rotational movement does not start and stop smoothly.
  • inverting heavy sand molds may also be viewed as a problem involving inertia. If the rotating jaws come to a stop too quickly, then the inertia of the relatively heavy sand mold supported therebetween will exert forces on the internal structure of the mold which can result in fracturing of the same. In theory at least, the jaws could be rotated very slowly and the likelihood of fracturing of the sand mold or of any damage occurring to the machine itself, or of the jaws rotating past their desired stop points, would be virtually eliminated. However, as a practical matter, in order for the roll over machines to function in a multi-station assembly line apparatus the inversion and re-inversion must be performed within a relatively short time interval, e.g. ten seconds.
  • the objective is to control the rate of rotation so as to substantially minimize the forces exerted on the internal structure of a mold for a given time interval in which the inversion must take place.
  • the optimum way in which to achieve this would be to rotate the jaws so that they accelerate at a constant positive rate through their first ninety degrees of revolution and thereafter decelerate through the remaining ninety degrees at a constant rate which is the negative of the initial acceleration.
  • the centre of mass of the sand mold will be below the axis X of rotation of the vertical frame and the upper and lower jaws. Therefore, the sand mold will travel through an arcuate path. It would be difficult to maintain an exact constant acceleration for the first ninety degrees of travel and an exact constant deceleration for the last ninety degrees of travel.
  • the present invention includes rotating means and means for controlling the rotating means which will cause the mold to move along an arcuate path so that its velocity increases at a substantially uniform rate along a first portion of the path and decreases at a substantially uniform rate along the remainder of the path. For a given time interval in which the inversion is to take place the forces that are exerted on the internal structure of the sand mold are substantially minimized.
  • Both the roll over draw and close apparatuses of the present invention utilize the hydraulic circuit shown in Figure 8.
  • a hydraulic pump 230 driven by an electric motor 232 pumps hydraulic fluid from a source or reservoir 234. The fluid is pumped through an infeed line 235 and through valves 236 and 238 to the hydraulic rotary actuator 110.
  • Hydraulic fluid can be supplied through a solenoid actuated on-off valve 240 to the hydraulic motor 188 which rotates the rollers 48 of the lower jaw 106.
  • hydraulic fluid can be supplied through a solenoid actuated on-off valve 242 to the hydraulic motor 186 which drives the rollers 48 of the upper jaw 104. Hydraulic fluid can be supplied through solenoid actuated valves 244 and 246 for actuating the hydraulic cylinder 180 to raise or lower the upper jaw 104.
  • the hydraulic pump 230 is a positive displacement, variable flow-type pump.
  • a compensator 248 is associated with the pump 230. It varies the flow or rate of displacement of the pump so that its output pressure is more or less constant.
  • a hydraulic pump suitable for this purpose is known as a variable displacement axial piston pump. It may be readily utilized with a pressure compensating control.
  • One suitable axial piston pump having a pressure compensating control is manufactured by Cessna Corp., Fluid. Plower Division, Hutchinson, Kansas.
  • the valve 238 controls the delivery of hydraulic fluid to and from the hydraulic rotary actuator 110. It is a commercially available block-type valve known in the hydraulic field as a counterbalance valve. Incorporated in this block-type valve are check valves 250 and 252 and graduated flow, pressure controlled sub-valves 254 and 256. These components are interconnected by conduits as indicated.
  • Hydraulic fluid can only flow downwardly through the sub-valves 254 and 256 in the direction indicated by the arrows.
  • the amount of hydraulic fluid which can flow downwardly through these sub-valves is varied according to the hydraulic fluid pressure in the criss-cross diagonal conduits 260 and 262.
  • the compensator 248 will sense the higher of the pressures in the conduits 272 and 258 through check valves 274 and 276. Thus, during the first ninety degrees of counter-clockwise rotation on the upswing, the gradual increase in pressure at the junction 265 and in the conduit 258 will be sensed.
  • the compensator 248 senses the difference between the hydraulic fluid pressure in the infeed line 235 and in the conduit 258 to vary the rate of displacement of the pump 230. Since the hydraulic rotary actuator 110 is a positive displacement device the rate of rotational movement imparted thereby is directly related to the rate at which hydraulic fluid flows into and out of the same.
  • the amount of work required of the actuator 110 will begin to decrease and accordingly the pressure on the pistons within the actuator will begin to decrease. This results in a gradual pressure drop at the junction 265 and in the conduit 258, resulting in a gradual closing of the sub-valve 254.
  • the pump 230 will deliver a gradually decreasing quantity of hydraulic fluid and the vertical frame will gradually and smoothly come to a stop at the 180 degree inverted position. The last fifteen degrees of rotation of the vertical frame is accomplished very slowly.
  • the hydraulic circuit is load sensitive. The greater the load or the work that must be done by the actuator 110, the faster the vertical frame 108 and the jaws mounted thereon will be rotated.
  • the sub-valve 256 will restrict the amount of hydraulic fluid which can flow into the return line 273 from the cylinders 264 and 266 of the actuator 110.
  • the hydraulic valve 236 is shifted to its direct flow position in which hydraulic fluid from the main infeed line 235 flows through the valve, through the conduit 272 and into the left side ⁇ the counter-balance valve 238.
  • a junction 278 adjacent the sub-valve 254 some of the hydraulicftuid will flow into the cylinders 268 and 270 of the actuator 110 and some of the hydraulic fluid will flow through the diagonal conduit 262 to slightly open the sub-valve 256.
  • the time interval during which the roll over operation is performed may be controlled by adjusting a flow control valve 280.
  • the speed of rotation of the rollers 48 of the upper and lower jaws may be independently controlled by adjusting flow control valves 282 and 284 respectively.
  • the speed at which the upper jaw 104 is moved toward and away from the lower jaw 106 may be controlled by adjusting a flow control valve 286.
  • a bleed line 287 with a flow control valve may be utilized to bleed off some of the pressure in the line which extends to the compensator 248.
  • the hydraulic rotary actuator 110, the hydraulic motor 186, the hydraulic motor 188, and the hydraulic cylinder 180 are each energized independently. That is to say, when one of them is receiving hydraulic fluid under pressure none of the others is.
  • the compensator 248 senses the pressure of hydraulic fluid which is delivered to the motor 188, the motor 186, and the cylinder 180 through check valves 288, 290 and 292, respectively. Hydraulic fluid drawn from the reservoir 234 by the pump 230 passes through a filter 294. Hydraulic fluid returned to the reservoir 234 through the return line 273 passes through a filter 296.
  • a circuit breaker switch 300 is manually thrown to connect the circuit to a 230/460 Volt, three phase, sixty Hertz electrical power source.
  • the electric motor 232 which drives the hydraulic fluid pump 230 ( Figure 8) is connected through relay contacts 302 and a fuse 304 to the terminals of the breaker switch 300.
  • the primary winding of a step down transformer 306 is connected to the electric power source through a fuse 308.
  • One lead of the second winding of the transformer 306 is connected through a fuse 310 to a hot line 312.
  • Another lead of the secondary winding of the transformer 306 is grounded and is connected to a line 314.
  • the remaining components of the electrical circuit are connected between the lines 312 and 314.
  • the roll over draw apparatus 14 is started by depressing a momentary switch 316 which causes a master control relay winding 318 to be energized. This in turn, causes relay contacts 320 and 322 associated with the master control relay winding 318 to close.
  • an indicator lamp 324 lights up to indicate that the roll : over draw apparatus is in its "power on” mode. If the lamp 324 does not light up when the momentary switch 316 is depressed, a tester switch 326 can be manually thrown. If the lamp 324 then lights up, the relay winding 318 and tlv relay contacts 322 should be checked for defects.
  • a momentary switch 328 is manually depressed to energize a relay winding 330. This closes relay contacts 332 and 302 associated with the relay winding.
  • the electric motor 232 is energized and begins to drive the hydraulic pump 230.
  • an indicator lamp 334 lights up to indicate that the hydraulic pump unit is on. If the lamp 334 does not light then a manual tester switch 336 can be thrown to determine if the relay 330 or the relay contacts 332 are defective.
  • the power to the circuit may be shut off by depressing a momentary switch 338 when it is desired to turn off the roll over draw apparatus.
  • a momentary switch 340 can be depressed to shut down the apparatus.
  • the hydraulic pump motor can be de-energized by depressing a momentary switch 342.
  • a limit switch 344 is mounted between an adjacent pair of the rollers 48 of the lower jaw 106 adjacent the discharge end thereof.
  • the limit switch 344 has a pivoting spring biased actuating arm 346 which normally extends above the upper peripheries of the rollers 48.
  • the limit switch 344 includes two ganged switches 344a and 344b ( Figure 9). The switch 344a is normally closed and the switch 344b is normally open. When a mold box is conveyed onto the lower jaw 106 the bottom wall thereof will depress the actuating arm 346 of the switch 344, opening switch 344a and closing switch 344 b .
  • the limit switch 344 is positioned so that the rollers 48 will stop rotating when the mold box is roughly centred on the lower jaw 106.
  • the switch 344b is closed. This energizes a solenoid 358 protected by a fuse 360, and a relay winding 362. The energization of the relay winding 362 closes relay contacts 364 which energizes a solenoid 366 protected by a fuse 368. The energization of the solenoids 358 and 366 shifts the hydraulic valves 246 and 244, respectively, so that hydraulic fluid flows into the hydraulic cylinder 180 and causes the upper jaw 104 to be lowered.
  • a limit switch 370 is mounted between a pair of adjacent rollers 48 of the upper jaw 104.
  • the limit switch 370 has a pivoting actuating arm 372 which is depressed by the bottom board resting on top of the mold box.
  • the switch 370 is positioned so that its actuating arm 372 will be depressed when the upper jaw 104 has descended far enough so that the mold box and bottom board are firmly clamped between the upper and lower jaws.
  • the limit switch 370 includes a pair of ganged switches 370a and 370b which are normally closed and open, respectively.
  • the switch 370a When the actuating arm 372 is depressed (after the mold box and bottom board have been clamped between the upper and lower jaws) the switch 370a will open and switch 370b will close. The opening of the switch 370a de-energizes the solenoids 358 and 366 and causes the upper jaw 104 to stop descending.
  • the closing of the switch 370b will energize a solenoid 374 protected by a fuse 376.
  • the energization of the solenoid 374 shifts the hydraulic valve 236 ( Figure 8) so that hydraulic fluid flows in to the hydraulic rotary actuator 110 and inverts the vertical frame 108 and the mold box and sand mold, i.e. rotates the upper and lower jaws counter-clockwise 180 degrees. As previously described in detail, this rotational movement starts and stops very smoothly and, thus, reducing the likelihood of fracturing of the sand mold.
  • the switch 380 is mounted to the inclined beam 118 on the other side of the stand 102.
  • the limit switch 380 includes a pair of ganged switches 380a and 380b ( Figure 9) which are normally closed and open, respectively.
  • switch 380 When the switch 380 is tripped by the lever 378 the switch 380a opens and the switch 380b closes.
  • the opening of switch 380a de-energizes the solenoid 374 and the spring biased hydraulic valve 236 ( Figure 8) shifts back to its neutral (no-flow) position terminating the flow of hydraulic fluid to the rotary actuator 110 and stopping the vertical frame 108 in the inverted position.
  • the closing of the switch 380b energizes time delay relays 382 and 384.
  • the energization of the time delay relay 382 closes relay contacts 385 which contacts 385 which causes solenoids 386 and 388 protected by fuses 390 and 392, respectively, to be energized.
  • the energization of the solenoid 386 shifts the pneumatic valve 222 to inflate the air bags 212. This moves the vibrating frames 210 ( Figure 5) into contact with the bottom wall of the mold box.
  • the energization of the solenoid 388 shifts the pneumatic valve 224 ( Figure 7) so that the vibrator 216 begins to impart vibratory movement to the mold box through the frames 210.
  • the energization of the time delay relay 384 closes relay contacts 394 causing a solenoid 396 protected by a fuse 398 to be energized.
  • the solenoid 396 shifts the hydraulic valve 246 ( Figure 8) to its flow reversing position.
  • the energization of the time delay relay 384 also energizes a relay winding 400 which in turn closes relay contacts 402.
  • the closing of the relay contacts 402 energizes the solenoid 366 and moves the hydraulic valve 244 ( Figure 8) to its on position. Hydraulic fluid begins to flow into the cylinder 180 to cause its piston rod 178 to extend.
  • the jaw 104 begins to descend (note the jaw 104 is now underneath the mold box).
  • the sand mold starts to be drawn from the mold box, the vibratory movements imparted to such box by the vibrator 216 facilitating the stripping of the mold from the box.
  • the time delay relay 384 opens a switch 406. This de-energizes the solenoids 396 and 366 and causes the jaw 104 to stop descending momentarily.
  • a proximity sensing device e.g. an infrared sensor
  • the jaw 104 can be mounted on the jaw 104 so that its scanning beam extends horizontally across the jaw an inch or so above the upper peripheries of the rollers 48 thereof, If, after the jaw 104 has descended several inches, the sand mold is stuck within the mold box and is not being stripped there from there will be a gap of several inches between the mold box and the bottom board supported on the rollers 48 of the jaw 104.
  • the proximity sensing device can be operatively connected to the circuitry to terminate the automatic operation of the roll over draw apparatus 16 and cause the illumination of a warning light under these circumstances. An operator can then override the apparatus manually and remove the mold box containing the sand mold which cannot be drawn from the mold box by the apparatus.
  • the circuitry for accomplishing the above is not shown in Figure 9.
  • the time delay relay 382 closes a switch 408 which again energizes the solenoids 396 and 366.
  • the jaw 104 starts to descend again and keeps descending until the sand mold, resting on top of the bottom board, has been completely drawn or stripped from the mold box.
  • the lower jaw 104 nears the end of the vertical frame 108 it trips a limit switch 410.
  • the limit switch 410 includes a pair of ganged switches 410a and 410b which are normally closed and open, respectively.
  • the switch 4l0a is opened and the switch 410b is closed.
  • the opening of the switch 410a de-energizes the solenoids 396 and 366 which causes the jaw 104 to stop descending.
  • the closing of the switch 410b energizes a solenoid 412 protected by a fuse 414.
  • the solenoid 412 shifts the hydraulic valve 242 ( Figure 8) causing the rollers 48 of the jaw 104 to rotate.
  • the bottom board and the sand mold supported thereon are discharged from the jaw 104 onto the main conveying line 20.
  • the bottom board which has been discharged from the jaw 104 closes a limit switch 416 ( Figure 9) mounted in the main conveying line 20 adjacent the box return mechanism 54 ( Figure 1, switch not indicated in the drawing). This energizes a relay winding 418 which closes relay contacts 420.
  • a solenoid 422 protected by a fuse 424 is energized. The solenoid 422 shifts the hydraulic valve 236 ( Figure 8) so that hydraulic fluid flows into the rotary actuator 110 and causes the same to re-invert the frame 108 and the jaws 104 and 106 in smooth, gradual fashion.
  • the frame 108 swings clockwise ( Figure 4) until the lever 378 ( Figure 3) secured to the side thereof trips a limit switch 424.
  • This switch is mounted on the inclined beam 118 on the other side of the stand 102 from the limit switch 380 ( Figure 5).
  • the limit switch 424 includes ganged switches 424a and 424b ( Figure 9) which are normally closed and open, respectively.
  • the tripping of the limit switch 424 by the lever 378 opens the switch 424a and closes the switch 424b.
  • the opening of the switch 424a de-energizes the relay winding 418 which inturn opens the contacts 420 and de-energizes the solenoid 422.
  • the de-energization of the solenoid 422 results in the hydraulic valve 236 ( Figure 8) shifting back to its middle or neutral position. This terminates the delivery of hydraulic fluid to and from the actuator 110 and the frame 108 stops rotating.
  • the closing of the switch 424b energizes a time delay relay 426. This closes relay contacts 428 and energizes another time delay relay 430. The energization of the time delay relay 430 closes relay contacts 432. After a short interval of time the switch 432 controlled by the time delay relay 426 opens.
  • a switch 434 controlled by the time delay relay 430 closes. This energizes the solenoid 350 which shifts the pneumatic valve 220 ( Figure 7). Pressurized air is delivered to the pneumatic cylinder 206 to cause the vertical flange gripping arms 190 ( Figure 5) to move forwardly. The mold box is thus no longer held between the vertical arms 190 and 192.
  • the switch 434 is closed by the time delay relay 430, the same relay also opens relay contacts 436 and 438.
  • the closing of the switch 434 also energizes the solenoid 348.
  • the energization of the solenoid 348 shifts the hydraulic valve 240 ( Figure 8) so that hydraulic fluid flows into the hydraulic motor 188.
  • the rollers 48 of the lower jaw 106 begin to rotate.
  • the mold box is discharged off of the lower jaw back onto the main conveying line 20.
  • the roll over close apparatus 18 of the present invention receives a cope portion 52 ( Figure 2A) of a sand mold conveyed thereto on a bottom board 40 by the main conveying line 20. Arms 56 of the roll over close apparatus clamp the cope portion 52 and raise it off of the bottom board 40 ( Figure 2A, steps G and H). The bottom board 40 is discharged out of the roll over close apparatus 18. Thereafter, the cope portion 52 is inverted, i.e. rolled over 180 degrees ( Figure 2A, step I). The cope portion 52 is maintained in an elevated position above the level of the main conveying line 20 awaiting the arrival of a drag portion 62 ( Figure 2B).
  • the drag portion 62 and the bottom board 64, upon which it rests, are conveyed into the roll over close apparatus 18 directly underneath the awaiting cope portion 52 ( Figure 2B, step K).
  • the cope and drag portions 52 and 62 are joined ( Figure 2B, step L) and they are conveyed, resting on top of the bottom board 64, out of the roll over close apparatus 18 back onto the main conveying line 20.
  • the mechanical structure of the roll over close apparatus 18 is similar in all respects to that of the roll over draw apparatus 16 except for certain structural details of its upper and lower jaws which are hereafter described.
  • the roll over close apparatus must also have a means for controlling the rotational movement so that it starts up and slows down smoothly. After the joined cope and drag mold portion are ejected from the roll over close apparatus, the empty jaws are re-inverted and in order to avoid damage to the machine, it is also desirable during the roll down that the rotation start and stop smoothly.
  • the roll over close apparatus utilizes the same means for rotating the jaws and the sand mold supported therebetween smoothly and gradually as previously described in conjunction with the roll over draw apparatus. It is even more critical that the vertical frame and jaws of the roll over close apparatus start and stop their rotational movement gradually. This is because the sand mold which is inverted by the roll over close apparatus is not contained and supported by a surrounding mold box. Therefore, the sand mold is even more susceptible to fracturing during the inversion. Preferably the rotational velocity increases and thereafter decreases at a substantially uniform rate.
  • the roll over close apparatus incorporates the same hydraulic circuit ( Figure 8) as the roll over draw apparatus.
  • the roll over close apparatus incorporates a pneumatic circuit ( Figure 12).
  • the roll over close apparatus includes an electrical control circuit ( Figure 13) which enables it to automatically perform the sequence of operations described above.
  • Figures 10 and 11 show structural details of the lower jaw 106' of one embodiment of the roll over close apparatus 18 of the present invention.
  • a cope portion 52 of a sand mold resting on a bottom board 40 is shown supported on the rollers 48 of the lower jaw 106'.
  • a pair of vertical arms 56a are rigidly welded in position at their lower ends.
  • the arms 56a extend vertically between the rollers 48 of the lower jaw.
  • a second pair of vertical arms 56b are welded at their lower ends to the forward part of a carriage 500.
  • the arms 56b also extend upwardly between the rollers 48.
  • the carriage 500 has wheels 501 which travel along transversely extending tracks 501a.
  • transversely extending gripping members 502. Pivotably secured to the upper ends of the respective pairs of arms 56a and 56b are transversely extending gripping members 502. These members have teeth on their inner surfaces 504 for firmly holding the sand mold 52.
  • a pneumatic cylinder 506 can be actuated to move the carriage 500 inwardly. When this occurs, the sand mold 52 will be firmly held between the gripping members 502.
  • the tracks 501a are held in position by four upper air bags 508 and four lower air bags 510.
  • the upper air bags 508 When the upper air bags 508 are not inflated the lower air bags 510 can be inflated to move the carriage 500 and the elements supported thereby upwardly ( Figure 11).
  • the air bags 510 When the air bags 510 are not inflated, the air bags 508 can be inflated to move the carriage 500 and the el p ments supported thereby downwardly.
  • a cope portion of a sand mold, resting on top of a bottom board is conveyed into the roll over close apparatus 18.
  • the cope portion of the sand mold comes to a stop intermediate the length of the lower jaw 106'.
  • the sand mold is clamped between the gripping members 502.
  • the lower air bags 510 are inflated to raise the sand mold 52 off of the bottom board 40.
  • the rollers 48 are momentarily rotated to discharge the bottom board off of the lower jaw 106' onto the main conveying line 20.
  • the vertical frame 108 and the upper and lower jaws of the roll over close apparatus 18 are rotated (counter-clockwise in Figure 4) 180 degrees to invert the cope portion 52.
  • the cope portion is maintained in an elevated position above the level of the main conveying line 20 awaiting the arrival of a drag portion 62 ( Figure 2B) on a bottom board 64.
  • the jaw 104 has guides (not shown) mounted above the rollers 48. The guides align the drag portion transversely with the cope portion suspended above the same as the drag is conveyed onto the jaw 104.
  • the jaw 104 is raised until the drag portion and the cope portion are joined.
  • the pneumatic cylinder 506 is actuated to release the cope portion from between the gripping members 502.
  • the jaw 104 and the joined cope and drag mold portions are lowered to the level of the main conveying line 20.
  • the rollers 48 of the jaw 104 are rotated to power the joined cope and drag portions off of the jaw 104 onto the main conveying line 20.
  • the vertical frame 108 and the jaws 104 and 106' are re-inverted back to their original position.
  • pressurized air is supplied through the rotary coupling 140 to a manifold 550 mounted on the lower jaw 106 t .
  • the pneumatic cylinder 506, which moves the vertical mold gripping arms 56b, is coupled to the manifold 550 through a flow reversing valve 552.
  • the air bags 508 and 510 are connected to the manifold 550 through a two position valve 554.
  • the valves 552 and 554 are solenoid actuated spring biased valves. When the valve 554 is in the position shown, the upper air bags 508 ( Figure 11) are inflated and the lower air bags 510 are deflated. When the solenoid of the valve 554 is energized it shifts the valve so that the upper air bags 508 are deflated and the lower air bags 510 are inflated.
  • the roll over close apparatus is placed in a power on mode by throwing a manual circuit breaker switch 600 and by pulling on a ganged start switch. 602a and 602b.
  • the closing of the switches 602a and 602b energizes a relay winding 604.
  • the energization of the relay winding 604 closes relay contacts 606 which causes the electric motor 232 ( Figure 8) to be energized.
  • the motor 232 drives the hydraulic pump 230.
  • the energization of the relay winding 604 also closes relay contacts 608 and 610 ( Figure 13).
  • a limit switch 612 is mounted between the rollers 48 of the lower jaw 106' in the same fashion as the limit switch 344 of the roll over draw apparatus ( Figure 4).
  • the limit switch 612 is normally open and is closed when its actuating arm is depressed by a cope portion conveyed onto the lower jaw 106' .
  • a solenoid 348 is in its energized state.
  • the solenoid 348 hold the on-off hydraulic valve 240 ( Figure 8) in its on position so that the rollers 48 of the lower jaw 106' are rotated.
  • the cope portion reaches the lower jaw 106' it will be conveyed longitudinally thereon until it is positioned intermediate the longitudinal length of the jaw.
  • the cope portion reaches this position on the lower jaw 106' it closes the limit switch 612 ( Figure 13).
  • This energizes a relay winding 614 which closes contacts 616 and 618.
  • the closing of the relay contacts 616 energizes a time delay relay 620.
  • the relay 620 closes contacts 622 to hold the relay energized.
  • the relay 620 opens relay contacts 624, de-energizing the solenoid 348 and stopping the rotation of the rollers 48 of the lower jaw 106'.
  • the relay winding 620 further opens contacts 626 which de-energizes a solenoid 628 causing the pneumatic valve 552 ( Figure 12) to shift to its flow reversing position. Pressurized air flows into the pneumatic cylinder 506 causing the arms 56b ( Figure 10) to move inwardly. The cope portion 52 is firmly held between the gripping members 502.
  • the energization of the time delay relay 620 also opens relay contacts 630 which has no effect at this time. Finally, the energization of the relay winding 620 closes a switch 632. This energizes a solenoid 634 which shifts the pneumatic valve 554 ( Figure 12) causing the lower four air bags 510 ( Figure 11) to be inflated &nd the upper four air bags 508 to be deflated. This'raises the cope portion off of the rollers 48 of the lower jaw 106'.
  • the closing of the switch 632 also energizes a time delay relay 636 which closes a switch 638 so that the solenoid 348 is energized.
  • the lower rollers 48 rotates long enough to eject the bottom board while the cope portion is elevated thereabove.
  • time delay relay 636 also closes a switch 640 which energizes another time delay relay 642. Finally, the energization of tle relay winding 636 closes contacts 644 which has no effect at this time since a limit switch 646, which senses the presence of a drag portion, is open at this time.
  • the time delay relay 642 opens a switch 648 which de-energizes the solenoid 348 and terminates the rotation of the rollers 48 of the lower jaw 106'.
  • the time delay relay 642 also closes a switch 650 which energizes the solenoid 374.
  • the energization of the solenoid 374 shifts the hydraulic valve 236 ( Figure 8) so that the vertical frame 108 of the roll over close apparatus rotates counter clockwise 180 degrees to invert the cope portion.
  • the lever 378 on the side of the vertical frame 108 (see Figure 3) trips the limit switch 380 ( Figure 5) mounted to the stand 102 of the apparatus.
  • the switch 380 includes a pair of ganged switches 380a and 380b ( Figure 13) which are normally closed and open respectively. The tripping of the limit switch 380 opens the limit switch 380a and closes the limit switch 380b.
  • the opening of the switch 380a de-energizes the solenoid 374 which in turn causes the hydraulic valve 236 ( Figure 8) to shift back to its neutral (no flow) position. This terminates the rotation of the vertical frame 108 of the roll over close apparatus.
  • the closing of the limit switch 380b ( Figure 13) energizes the solenoid 412.
  • the energization of the solenoid 412 shifts the hydraulic valve 242 ( Figure 8) to its on position causing the rollers 48 of the upper jaw 104 to rotate.
  • a drag portion 62 ( Figure 2B) is conveyed on the main conveying line 20 onto the rollers 48 of the jaw 104 now positioned at the level of the main conveying line 20.
  • the drag portion closes the limit switch 646. This switch is mounted between the rollers 48 of the jaw 104.
  • the closing of the limit switch 646 energizes a relay winding 652.
  • the energization of the relay winding 652 opens relay contacts 654, de-energizing the solenoid 412 and terminating the rotation of the rollers 48 of the jaw 104.
  • the energization of the relay winding 652 also closes relay contacts 656 which has no effect at this time.
  • the energization of the relay winding 652 also closes relay contacts 658.
  • the closing of the drag present limit switch 646 also I energizes the solenoid 358, the contacts 644 having previously been closed by the time delay relay 636.
  • the closing of the relay contacts 658 by the relay winding 652 energizes the solenoid 366.
  • the energization of the solenoids 358 and 366 causes hydraulic fluid to flow into ; the cylinder 180 ( Figure 8) which raises the jaw 104 toward the jaw 106' thereabove.
  • the drag portion is mated with the cope portion.
  • the cope portion is still held between the gripping members 502 of the arms 56a and 56b ( Figure 10) at this time.
  • the air bags 510 ( Figure 11) are still inflated ao that the cope portion 52, resting on top of the drag portion, is held spaced from the rollers 48 of the jaw 106'. Therefore, at this time the limit switch 612 ( Figure 13) mounted between the rollers 48 of the jaw 106' is open. The rising jaw 104 lifts the cope portion into engagement with the switch 612 closing the same.
  • the closing of the limit switch 612 re-energizes the relay winding 614.
  • the energization of the relay winding 614 closes relay contacts 616 and 618.
  • the closing of the relay contacts 618 causes a time delay relay 660 to be energized, the relay contacts 656 having previously been closed by the energization of the relay 652.
  • the energization of the time delay relay 660 opens contacts 662 and de-energizes the time delay relay 620.
  • the de-energization of the relay winding 620 also opens the switch 632, de-energizing the solenoid 634 and the time delay relay 636.
  • the de-energization of the solenoid 634 inflates the air bags 508 and deflates the air bags 510 lifting the sub-frame 500 ( Figure 11) and the arms 56a and 56b carried thereby.
  • the de-energization of the time delay relay 636 opens relay contacts 644 and 638. Opening of the contacts 644 de-energizes solenoid 358 and the jaw 104 stops rising. It also opens switch 640, de-energizing the time delay relay 642.
  • the energization of the time delay relay 660 also opens relay contacts 664 which has no effect at this point.
  • the energization of the time delay relay 660 further closes relay contacts 666 and closes relay contacts 668
  • the de-energization of the time delay relay 620 opens the relay contacts 622 which has no effect at this time. It further closes the relay contacts 624 which also has no effect at this time. Finally, the de-energization of the time delay relay 620 closes the relay contacts 626, energizing the solenoid 628. The energization of the solenoid 628 shifts the pneumatic valve 552 ( Figure 12) so that the cope portion is released by the gripping arms 56a and 56b ( Figure 10). The de-energization of the time delay relay 620 further closes the relay contacts 630.
  • the solenoid 396 is energized and since the solenoid 366 has been previously energized hydraulic fluid flows into the cylinder 180 cuasing the jaw 104 and the joined cope and drag portions supported thereon to descend.
  • the jaw 104 carrying the joined cope and drag portions continues to descend until the limit switch 410 (see Figure 5) is actuated.
  • the limit switch 410 includes ganged switches 410a and 410b which are normally closed and open, respectively. When the limit switch 410 is engaged by the jaw 104 the switch 410a is opened and the switch 410b is closed. The opening of the switch 410a de-energizes the solenoid 396 and the jaw 104 stops descending. The closing of the switch 410b energizes a time delay relay 672.
  • the energization of the time delay relay 672 closes contacts 674, energizing the solenoid 412 and causing the rollers of the jaw 104 to rotate.
  • the joined cope and drag portions 52 and 62, resting on top of the bottom board 64, are discharged out of the roll over close apparatus 18 onto the main conveying line 20.
  • the time delay relay 672 opens a switch 676, de-energizing the solenoid 412 and terminating the rotation of the rollers 48 of the jaw 104.
  • the time delay relay 672 closes a switch 678, energizing the solenoid 422.
  • the energization of the solenoid 422 shifts the hydraulic valve 236 ( Figure 8) cuasing the vertical frame 108 of the roll over close apparatus to swing counter-clockwise 180 degrees.
  • the lever 378 Figure 3
  • the limit switch 424 opening the same and de-energizing the solenoid 422 ( Figure 13).
  • the de-energization of the solenoid 422 allows the hydraulic valve 236 ( Figure 8) to shift back to its middle position, thus terminating the rotation of the vertical frame 108. This completes the cycle of operation.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Casting Devices For Molds (AREA)
EP80301293A 1979-04-23 1980-04-22 Vorrichtung zum Wenden einer Sandform Ceased EP0018232A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US3217979A 1979-04-23 1979-04-23
US32179 1979-04-23

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EP80301293A Ceased EP0018232A1 (de) 1979-04-23 1980-04-22 Vorrichtung zum Wenden einer Sandform

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EP (1) EP0018232A1 (de)
JP (1) JPS55144361A (de)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0945070A1 (de) * 1998-03-26 1999-09-29 Soremartec S.A. Umkehrvorrichtung für Formen
CN108687334A (zh) * 2018-08-20 2018-10-23 共享智能铸造产业创新中心有限公司 一种砂型翻转装置
CN114474348A (zh) * 2022-02-09 2022-05-13 曹树梁 陶瓷太阳板注浆成型基体素坯出模装置与出模方法
CN114918384A (zh) * 2022-05-30 2022-08-19 重庆林洲机械制造有限公司 一种起模系统及控制方法
CN115770858A (zh) * 2022-11-22 2023-03-10 无锡中叶合金制品有限公司 Ct皮带轮铸造型砂填充装置
CN117733080A (zh) * 2024-02-21 2024-03-22 江苏松林汽车零部件有限公司 减速机箱体覆砂输送线

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR965845A (de) * 1950-09-22
FR1052872A (fr) * 1951-05-08 1954-01-28 Ferro Eng Co Procédé et appareil perfectionnés pour la remise en état des têtes calorifuges de lingotières
CH350432A (de) * 1956-05-26 1960-11-30 Badische Maschinenfabrik Ag Se Vorrichtung zum Wenden der Unterformkasten zwecks Einlegens der Kerne, bei automatisch arbeitenden Anlagen zum Herstellen von giessfertigen Formen
CH356569A (de) * 1957-01-15 1961-08-31 Badische Maschinenfabrik Ag Vorrichtung zum Wenden der Unterformkasten bei automatisch arbeitender Anlage zur Herstellung giessfertiger Formen

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR965845A (de) * 1950-09-22
FR1052872A (fr) * 1951-05-08 1954-01-28 Ferro Eng Co Procédé et appareil perfectionnés pour la remise en état des têtes calorifuges de lingotières
CH350432A (de) * 1956-05-26 1960-11-30 Badische Maschinenfabrik Ag Se Vorrichtung zum Wenden der Unterformkasten zwecks Einlegens der Kerne, bei automatisch arbeitenden Anlagen zum Herstellen von giessfertigen Formen
CH356569A (de) * 1957-01-15 1961-08-31 Badische Maschinenfabrik Ag Vorrichtung zum Wenden der Unterformkasten bei automatisch arbeitender Anlage zur Herstellung giessfertiger Formen

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0945070A1 (de) * 1998-03-26 1999-09-29 Soremartec S.A. Umkehrvorrichtung für Formen
CN108687334A (zh) * 2018-08-20 2018-10-23 共享智能铸造产业创新中心有限公司 一种砂型翻转装置
CN108687334B (zh) * 2018-08-20 2023-10-31 共享智能铸造产业创新中心有限公司 一种砂型翻转装置
CN114474348A (zh) * 2022-02-09 2022-05-13 曹树梁 陶瓷太阳板注浆成型基体素坯出模装置与出模方法
CN114918384A (zh) * 2022-05-30 2022-08-19 重庆林洲机械制造有限公司 一种起模系统及控制方法
CN115770858A (zh) * 2022-11-22 2023-03-10 无锡中叶合金制品有限公司 Ct皮带轮铸造型砂填充装置
CN115770858B (zh) * 2022-11-22 2023-11-03 无锡中叶合金制品有限公司 Ct皮带轮铸造型砂填充装置
CN117733080A (zh) * 2024-02-21 2024-03-22 江苏松林汽车零部件有限公司 减速机箱体覆砂输送线
CN117733080B (zh) * 2024-02-21 2024-05-14 江苏松林汽车零部件有限公司 减速机箱体覆砂输送线

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