Turn-over device for slab materials
This application is a continuation-in-part of application Ser. No. 755,209, filed Dec. 29, 1976, now abandoned. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to turn-over devices and, in particular, to a turn-over device for use in the steel industry for heavy slab materials, as well as for other purposes requiring turn-over operations. 
     BACKGROUND OF THE INVENTION 
     Turn-over devices for use in the steel industry are known and usually comprise a four wheel carriage running on two rails arranges transverse to the path of the conveyor. On the carriage, two tongues are mounted, each of them actuated by a hydraulic cylinder and an integral part of a two pinion shaft which gears in two racks, these also actuated by two other hydraulic cylinders. The carriage is advanced on the tracks by another hydraulic cylinder, independent of the first four. 
     The slab material to be turned over is engaged by the two tongues driven by the first two cylinders, turned over through 180° with the help of the other two cylinders which drive racks and pinions, and the fifth cylinder moves the carriage to the desired position where the slab is to be let down. 
     The drawbacks of these devices lie in the complexity and excessive sophistication of the structure; three distinct drives with five hydraulic cylinders requiring their own hydraulic station and the highly skilled personnel required to operate the device. Also, the device is not integrated physically into the conveyor line in which it serves and therefore occupies a large space on either side of the conveyor since it must move transversely thereto. 
     OBJECTS OF THE INVENTION 
     It is therefore an object of the invention to provide an improved turn-over device for the purposes described with simplicity of structure. 
     It is another object of the invention to provide a turn-over device having a single drive element. 
     It is still another object of the invention to provide a turn-over device, especially for a steelmill, which will turn the slab material within the boundaries of the conveyor path, i.e. in place. 
     It is yet another object of the invention to provide a turn-over device which does not require extensive space on either side of the conveyor line. 
     And another object of the invention is to provide a turn-over device which is easily integrated into the conveyor line, not requiring extensive hydraulic installations. 
     SUMMARY OF THE INVENTION 
     The above and other objects of the invention are realized in a system which comprises a first pair of movable arms lying in parallel but spaced-apart relationship just beneath the path of a roller or other type of conveyor used for advancing slab materials. The first pair of arms are flanked on their outer sides by a second pair of arms which are swingable in a coordinated relationship with the first pair of arms. 
     The first pair of arms are each provided with a wheel at one end of each arm which engages a track provided between each set of flanking first and second arms. Each track is provided with an upper and lower run which acts as a guide for the first pair of arms, which when advanced forward are guided upwardly while maintaining a horizontal orientation and into engagement with the slab to be turned over. Both pairs of arms are driven by a series of connecting rods and levers, articulated to a pair of rotating cranks which impart a reciprocal motion to the levers which in turn impart a repeating cyclical movement to the arms. 
     After engagement with the slab, the first pair of arms are swung into a vertical position by one of the connecting rods articulated to the front end thereof, while the rear end carrying the wheels is advanced forward along the upper run of the tracks by another connecting rod articulated to the rear end. In coordination with this movement of the first arms, the second pair of arms swings upwardly in a sense opposite to that of the first pair to receive the slab as the first pair of arms passes beyond the vertical position, and lowers the slab onto the conveyor in a turned over position. As the first pair of arms rides back along the track on its wheels, its wheels are switched to the lower run so that when the front end of the arms are lowered, the entire arm will lie below the path of the conveyer and in position to repeat the cycle. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The specific details of the invention and the mode of functioning will be described in connection with the accompanying drawing wherein: 
     FIG. 1 is a top view of the device in position along a conveyer path; 
     FIG. 2 is a sectional view taken along line II--II of FIG. 1; 
     FIGS. 3-5 are views similar to that of FIG. 2 showing the device in different positions during its cycle; and 
     FIG. 6 is a view similar to that of FIG. 2 showing a different drive element. 
    
    
     SPECIFIC DESCRIPTION 
     Referring first to FIG. 2, it can be seen that a pair of cranks 3 and 4 are driven in the direction of arrow A by a motor 1 connected through a flexivle coupling 5 to a transmission 1&#39; having a pair of output shafts 2 connected through additional flexible couplings 5 to the cranks 3 and 4, this drive arrangement being best seen in FIG. 1 and in FIG. 5 where it is shown in phantom lines. 
     The crank 3 is articulated to one end of a connecting rod 6 which has its other end articulated to a lever 7 fixedly mounted on a shaft 8 journaled for rotation in a pair of supports 9, by the lever 7. 
     A lever 10 is fixedly mounted on the shaft 8 and driven thereby to rotate another lever 12 articulated to the lever 10 by a connecting rod 11. The lever 12 in fixedly mounted on another shaft 13, journaled for rotation in supports 14. Another lever 15 is fixedly mounted on the shaft 13 for rotation thereby, imparting a linear movement to an arm 17 which is articulated to the lever 15 by a connecting rod 16, at the rear end of arm 17. 
     Another lever 21 is fixedly mounted on shaft 8 for rotation thereby, imparting a swinging movement to the arm 17 about its rear end, the arm 17 being articulated at its front end to the lever 21 by a connecting rod 22. 
     The crank 4 is articulated to a lever 25 by a connecting rod 24, the lever 25 being fixedly mounted on a shaft 26 journaled for rotation in supports 27, by the lever 25. An arm 28 is fixedly mounted on the shaft 26 for rotation thereby. 
     The arm 17 is provided at its rear end with a wheel 20 which is guided along a track T having an upper run 18 and a lower run 33. The arms 17 and 28 as well as the track T lie just beneath the path of a roller-type conveyor C used for advancing slabs S, as shown in phantom lines. As the arm 17 is advanced forward by the lever 15,it is guided onto the upper run 18 of track T by the wheel 20. At the same time, the front end of arm 17 is lifted by the connecting rod 22, so that the arm 17 remains horizontal as in moves into the path of the conveyor C and engages the slab S with a row of rollers 17&#39; provided on the arm 17, as shown in FIG. 3. 
     As the cranks 3 and 4 continue to turn, the arm 17 advances further along the upper run 18 on the wheel 20 while the fromt end of the arm is swung upwardly by connecting rod 22, causing the slab S to roll backward against an abutment 23 formed on arm 17 for supporting the slab as the arm approches the vertical position, as shown in FIG. 4. As the arm 17 approaches the vertical position, the wheel 20 passes over and closes a switch 32, formed in the upper run 18, and normally held open by a spring (not shown). 
     As the arm 17 swings upwardly in a clockwise sense, driven by the lever 25, in a coordinated movement with arm 17, so that both arm reach the vertical position at the same time, the arm 28 making contact with the slab S with rollers 28&#39; provided thereon. Another arm 30 pivoted at 31 is formed with a pin 29 which is entrained in a slot a formed in the arm 28, so that as the arm 28 swings into a vertical position, the arm 30 follows, forming an abutment with a pair of rollers 30&#39; provided thereon, at the same level as the abutment 23, for holding the slab S after it is received by arm 28 from arm 17 when that arm passes beyond the vertical position, as shown in FIG. 5. 
     As the cranks 3 and 4 pass through 180°, the various levers begin to swing back through the second half of the cycle, the wheel 20 of arm 17 being directed to the lower run 33 of track T by the open switch 32, while at the same time, the arm 28 carrying the slab S, swings downwardly to return the slab to conveyer in a turned-over position. As arm 17 returns to its starting point, the wheel 20 passes through a switch 19, as shown in phantom lines in FIG. 5, which is normally held closed by gravity and serves to direct the wheel 20 to the upper run 18 at the start of the cycle. 
     As can be seen in FIG. 1, the arms and tracks are in pairs which are parallel but spaced apart, each set of arms 17, 28 and 30 and tracks T forming an interleaved group spaced apart from an identical interleaved group, each group having its attendent levers and connecting rods driven by common shafts 8, 26 and 13 which in turn are driven by single levers 7 and 25 and connecting rods 6 and 24 respectively. 
     FIG. 6 shows an alternate drive group comprising a pair of hydraulic cylinders 3&#39; and 4&#39; having respective piston rods 6&#39; and 24&#39; articulated respectively to levers 7 and 25, the rest of the mechanism being identical to the already described. The cylinders 3&#39; and 4&#39; are swingably mounted in trunnions to compensate for the angular differences encountered during the cycle.