US2730251A - Hoist or off-bearer for use in concrete block molding machines - Google Patents

Description

Jan. 10, 1956 W. G. SCH UTT HOIST 0R OFF-BEARER FOR USE IN CONCRETE BLOCK MOLDING MACHINES Original Filed April 3, 1948 3 Sheets-Sheet l {I J I 7 J I 0 ki i Q N INVENTOR. a Wo/zer G. Schuii ATTORNEYS.

TT 2,730,251 FOR USE IN CONCRETE BLOCK MOLDING MACHINES Original Filed April 3, 1948 Jan. 10, 1956 w. G. SCHU HOIST OR OFF-BEARER 5 Sheets-Sheet 2 PRESS URE INVENTOR Schu ff 2,730,251 Patented Jan. 10, 1956 fee HOIST OR OFF-BEARER FOR USE IN CONCRETE BLOCK MOLDING MACHINES Walter G. Schutt, Adrian, Micl1., assignor to Stearns Manufacturing Company, Adrian, Mich, a corporation of Michigan Original application April 3, 1948, Serial No. 18,798. Divided and this application April 2, 1951, Serial No. 218,719

2 Claims. (Cl. 214-452) This invention is a division of application Serial No. 18,798, filed April 3, 1948, and now Patent No. 2,640,- 579, and relates to a hoist or off-bearer for use in concrete block molding machines. In the aforementioned application there is described a conveyor system for taking pallets from a position in front of the concrete block molding machine and conveying them across the side of the machine to a somewhat elevated position where they are dropped into a magazine to form a stack. Then the pallets are taken one by one off the bottom of the stack and fed into the concrete block machine where the mold box comes down on top of the pallet, the concrete aggregate material is fed by a feed or strike-off drawer from a magazine and dropped into the cavities of the mold box. Thence the mold box is vibrated. The molded blocks are completed. The mold box is stripped off the molded blocks and the pallet with the concrete blocks is pushed out of the machine and at the same time another pallet is pushed into the machine.

It is the object of the present invention to provide an off-bearer or hoist which can handle one or more pallets loaded with the concrete blocks and also lift the empty pallets and drop them on the conveyor.

Referring to the drawings:

Fig. 1 is a perspective showing the concrete block molding machine and the conveyor.

Fig. 2 is a perspective of the off-bearer or hoist.

Fig. 3 is a cross sectional detail of the valve that controls the pneumatic or hydraulic hoist.

Fig. 4 is a fragmentary front elevation of the projecting pallet bearing arms, the conveyor showing in dotted lines how the pallets are lifted out of the machine and in full lines how the empty pallet is held above the conveyor for dropping.

Fig. 5 is a view partly in section showing the side or upgoing portion of the conveyor.

Fig. 6 shows the rear section of the conveyor and shows in section the pallet magazine.

Fig. 7 is an elevational view of the hoist and the supporting beam.

1 designates the frame of the concrete block machine. This machine is capable of performing the operations specified above in the preamble. These need not be shown or described. for molding these concrete blocks with continuously cycling operations is shown in my prior application, Serial No. 2,233, filed January 14, 1948. The conveyor is described and claimed in the parent application, Serial No. 18,798.

The pallets P shown in Fig. 4 are lifted by the arms 4 of the hoist H which can go in between the arms 2 that project out of the concrete block molding machine at the front and serve as seats for the two pallets P. Each pallet carries three molded blocks B. The hoist H contains a piston and is supplied with fluid through a tube iii leading to the valve 7 shown in Fig. 3. The trigger bar 9 may be pulled or pushed to operate the crank 50, which is connected by the shaft 51 with valve 7 so that the passageway 52 can be caused to connect with the tube 40 and the tube 41, thereby putting the fluid pressure in the cylinder at the top and causing the cylinder H together with the arms 4 to rise and thereby, when the hoist arms are under the pallets as shown in Fig. 4, lifting the pallets and the blocks B ofi the rolls on the arms 2 projecting from the machine. The piston 10 is carried on a piston rod 11 which is supported by a carriage 12 (see Fig. 7) which rides on the tracks 14 on the long beam 15 which is hinged at 16 on the bracket 17. Inasmuch as the beam 15 may be swung through a large arc and inasmuch as the carriage 12 can travel on the tracks 14 on the beam, the hoist has quite a large operating area.

The loaded pallets are taken by the hoist and the pallets are put on the angle iron ledges 26 of the curing rack R. A rack, with empty pallets, is shown at the left in One of these racks is loaded with pallets bearing blocks and will then be moved to a place where the pallets will be allowed to cure and dry. After the loaded pallets are put in the curing rack, the off-bearer then is taken to a rack which has empty pallets and the forks or arms are pushed into the rack and dropped down on two pallets as shown in Fig. 1. The operator then pushes switch button 27 and this turns on the current which, through the wiring 18 on the arms 4 electromagnetizes the arms. The arms can now lift the pallets from the racks and convey them to the position shown in the full lines of Fig. 4 where they are dropped on the rollers 19. Then they are picked up by the chain conveyors 2i and the chains 21. The hoist is guided and caused to operate by the operator using the handles 53 and 54. The two chains 34 and drops onto the rear conveyor chains 35. Thence the pallets are forced under the roller 37 and into an opening in the magazine 36. There they build up the stack 33 and the lowermost pallets are shoved into the machine by a pusher which is shown in application Serial No. 2,233, but which need not be here described. The machine can go through a complete cycle in approximately ten seconds and produce a pallet with three blocks. When two pallets are pushed out on the arms 2 as shown in Fig. 1, they may be picked up by the off-bearer and conveyed to a curing rack. There they are deposited on the ledges and the hoist goes over to another curing rack filled with empty pallets and the pallets are picked up by electromagnetizing the arms and then dropping them on the conveyor as shown in Fig. 4. They then pass up the conveyor shown in Fig. 5 and thence into the magazine as shown in Fig. 6.

Inasmuch as this ofi-bearer handles two pallets at a time, the operator has twenty seconds to take the pallets pallets while the machine is going cycles.

What I claim is: 1. The method of handling pallets in a concrete or of an empty pallet in a rack and conveying the pallet back to the machine while magnetically gripping the top of the palleeand then releasing the pallet at the machine by, derenergizingnthe.electromagnetic tool...

2. The method of handling pallets in a concrete or cement block forming machine which comprises the use of an .eleetromagnetic.tool to. liftrtwo loaded pallets out-oi themachineaby putting. the tool under the-pallets-and physically lifting the loadedpallets, conveying them and 5 putting. them into a .rackand then magnetically attaching thettool .to the top of an empty pallet in a rack and conveyingv thepallet back to the. machine while magnetically gripping the .top of the. pallet and then releasing the pallet at themachineby de-energizing the electromagnetic 4 References Cited in the file of this patent UNITED STATES PATENTS 1,563,949 Baker Dec. 1, 1925 1,836,690 Talbot Dec. 15, 1931 2,553,378 Miller May 15, 1951 2,574,131 Steinbrecher Nov. 6, 1951

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