1、英文原文英语原文Sand mixerAbstract:A foundry sand mixer for mixing and dispensing silica or green sand and their additives through the enclosed longitudinal belt conveyor mechanism having a plurality of openings in the top communicating with a first feeder disposed above the enclosed longitudinal belt conve
2、yor mechanism and including a pair of openings in the bottom. The first feeder includes an auger-type conveyor and a sand weir communicating with the most upstream opening in the first feeder. A first hopper for containing silica sand and a second hopper for containing green sand are disposed over t
3、he first feeder. A selective valve is disposed at the bottom of each of the first and second hoppers permitting the flow of sand through only one of the hoppers at any time or preventing the flow of any sand from the hoppers. The mixer may include additional feeders, some of which are disposed above
4、 and downstream from the first feeder, and others including pumps are connected to a plurality of fluids that are fed through a constant speed mixer where the materials are mixed and the mixed materials delivered at a discharge opening. Inventors:Frankie, Donald M. (1599 Gull La., Mound, MN, 55364)C
5、laims: 1. In a foundry sand mixer for mixing and dispensing silica or green sand and their additives, the combination comprising: (a) a support frame pivotal about a vertical axis and having a platform extending radially therefrom; (b) an enclosure including an enclosed longitudinal belt conveyor me
6、chanism extending above said platform and having a plurality of openings in the top of the enclosure communicating with said belt conveyor mechanism; (c) first feeder means disposed above and at the most upstream location of said enclosed longitudinal belt conveyor mechanism, said first feeder means
7、 having a bottom and converging sloping sides communicating near the bottom with an auger-type conveyor, and having a pair of openings longitudinally separated in the bottom thereof feeding said belt conveyor;(d) a sand weir communicating with the most upstream opening of said pair of openings in sa
8、id first feeder means, said sand weir disposed above said longitudinal belt conveyor mechanism for dispersing sand on said belt conveyor mechanism; (e) a first hopper for containing silica sand disposed over the upstream portion of said first feeder means;(f) a second hopper for containing green san
9、d disposed downstream from said first hopper and over said first feeder means; (g) selective valve means disposed at the bottom of each of said first and second hoppers permitting the flow of sand through only one of said hoppers at any time or preventing the flow of any sand from said hoppers; (h)
10、and control means operably connected to said selective valve means for selecting one of said two sands or neither to be dispensed onto said belt conveyor.2. The structure set forth in claim 1 including: (i) a plurality of second feeder means disposed above said belt conveyor mechanism and at a downs
11、tream location from said first feeder means, each of said plurality of second feeder means having a bottom and converging sloping sides communicating near the bottom with an auger-type conveyor and having an opening in the bottom thereof feeding said belt conveyor; (j) a constant speed mixer dispose
12、d on said platform and arranged to receive granular and liquid materials, mix the materials and deliver the mixed materials at a discharge opening, said belt conveyor communicating with said mixer; (k) and a plurality of pump means connected to a plurality of fluids and communicating with said mixer
13、Description: This invention relates to the field of mixers and more particularly to the field of foundry sand mixers for mixing silica or green sand and their additives. BACKGROUND OF THE INVENTION While the art of mixing foundry sand per se through a mechanical process is generally known, there ar
14、e attendant problems in attempting to use the same equipment for mixing green sand and its additives as generally might be used in a mixer using silica sand and its additives. Because of the inherent differences in the materials to be mixed and passed through the machine, the practice has generally
15、been to use separate machines for each of the different foundry sand materials and processes. SUMMARY OF THE INVENTION The embodiments of this improvement invention makes it possible to combine the necessary equipment into a single machine to mix either green sand or silica sand and their additives.
16、 Various means have been attempted to mix green sand which requires the addition of such other granular and dry ingredients as fire clay, bentonite, sea coal, pitch, wood flour and the like, along with an appropriate mixture of water. On the other hand, silica sand, which may also be known as a no-b
17、ake sand, is generally mixed with dry granular materials such as chromite and ferric oxide and several liquid ingredients which may include certain chemicals. Because certain green sand molds may be broken down after use and reused, green sand, when mixed with such components, provides a different f
18、low pattern than that of silica sand. Silica sand flows through hoppers and equipment much like the flow of water whereas green sand has additional additives and mixtures that generally make it lumpy with attendant flow problems. Various means have been devised in the past to make a slurry of the ad
19、ditives and add them to the green sand but the mechanism does not prove to be useful in working with both types of molding sand. One such mechanism is that disclosed in U.S. Pat. No. 3,070,858 issued to J. S. Beacon. It is also known that certain silica sand or no-bake sand mixers have been availabl
20、e but are not operable to run green sand through them and mix the green sand in the manner generally attributable to silica sand. One such disclosure of a mechanism of this type is found in U.S. Pat. No. 3,682,448 isued to Kedzior et al. The present invention is an improvement upon the mechanism dis
21、closed in my earlier U.S. Pat. No. 4,140,246 entitled PROPORTIONAL CONTROL SYSTEM FOR FOUNDRY SAND MIXING DEVICE. It is therefore a general object of the present invention to provide an improvement in foundry sand mixing equipment. It is a more specific object of this invention to provide a foundry
22、sand mixer that will mix either silica sand or foundry green sand and their additives. It is yet another object of this invention to provide a foundry sand mixer in which either silica sand or foundry green sand is controlled by a valve mechanism selectively depositing one or the other on a belt con
23、veyor for proper mixing. These and other objects and advantages of the invention will more fully appear from the following description, made in connection with the accompanying drawings, wherein like reference characters refer to the same or similar parts throughout the several views, and in which:
24、FIG. 1 is a perspective view of the invention; FIG. 2 is a schematic diagram of the mixer control circuit; FIGS. 3A and 3B are schematic diagrams of the drive circuits for all of the variable speed motors driving feeders and pumps in the invention; FIG. 4 is a diagram of the control panel on the end
25、 of the mixer; and FIG. 5 is a schematic diagram of the selective sand valve. PREFERRED EMBODIMENT Reference is now made to FIG. 1 wherein the foundry sand mixer 10 is disclosed. The mixer is secured to a base 11 that has a vertical axis about which a housing 12 pivots, housing 12 having a cantileve
26、r beam 13 extending radially therefrom. At the upstream end of the mechanism, a bracket 14 supports one end of an enclosed conveyor mechanism 15 and the other end of conveyor mechanism 15 is supported by a chute 16 that acts as a support bracket that is indirectly secured to beam 13. A belt conveyor
27、 17 is disposed within the housing 15 and is supported for movement by a plurality of horizontal transversely oriented rollers 20. A direct current drive motor 21 is connected to the downstream end roller to drive the belt conveyor mechanism 17. Disposed above the enclosed conveyor 15 is a first fee
28、der 22 which is elevated slightly above the conveyor enclosure 15. Feeder 22 is in the nature of a container having sloping sides converging at the bottom with an auger-type conveyor 23 driven by a variable speed motor 24. Feeder 22 has its sides extending upwardly at an angle of approximately 30 de
29、grees with a vertical and it has been found that if the sides extend outwardly so that the angle with the vertical is approximately 45 degrees, flow of the green sand will be encumbered. Feeder 22 has two openings in the bottom thereof, the first terminating in a sand weir 25 which is at the upstrea
30、m location with respect to the longitudinal dimension of the feeder and is directly beneath a silica sand hopper 26. Disposed downstream from said weir 25 is a tubular member 27 that communicates between an opening 30 in the bottom of first feeder 22 and the top of the enclosed conveyor mechanism 15
31、 Disposed across the opening 30 is a scarifier 31 in the nature of two right angle diametrically oriented rods that are used to break up any lumps that may still exist upon being conveyed to that opening by auger conveyor 23. Silica sand hopper 26 is disclosed as being generally rectangular in shap
32、e having a common side 32 which acts as a separator with another hopper 33 that is used to contain green sand. The sides of the hoppers slope downwardly in a converging manner and are terminated in a pair of chutes 34 and 35. A selective valve 36 is disposed across the openings of chutes 34 and 35 s
33、o that upon movement to the right (as seen in FIG. 1) sand will flow from hopper 26 through chute 34 into first feeder 22 but block flow of sand through chute 35 and upon movement to the left, valve means will permit flow of green sand from hopper 33 through chute 35 but block the movement of silica
34、 sand. In other words, either silica sand or green sand is admitted during the two extreme movements and while the valve is in its center position, sand is restricted from movement into either chute 34 or 35. Selective valve 36 is controlled by an air cylinder 37 that has a piston rod 38 connected t
35、o valve 36 through a linkage 40. A solenoid actuated valve 41 is connected to a source of pressurized air 42 through a pneumatic line 43. The source of air under pressure is generally 100 psi for good operating conditions. A pair of pneumatic lines 44 and 45 connect solenoid valve 41 with air cylind
36、er 37 and the solenoid coils are controlled through an electrical circuit connected to the solenoid valve 41. A 110 volt source is connected through a common lead 46 to solenoid valve 41 and one coil has its return current path through a conductor 47 and one terminal of a single pole double throw sw
37、itch 50. The switch blade is connected to the other terminal of the 110 volt source through a conductor 51. Another coil in the solenoid valve 41 is connected through the electrical circuit by a conductor 52 connected to another terminal of switch 50. As disclosed in FIG. 5, when the switch blade is
38、 connected with conductor 47, the silica sand or no-bake sand is permitted to pass through valve mechanism 36 and when the other portion of the solenoid valve is actuated through conductor 52, the green sand is permitted to pass through valve 36. A second feeder 53 is disposed above the conveyor enc
39、losure 15 downstream from first feeder 22. Second feeder 53 has the same general shape and configuration as that of first feeder 22 and includes a conveyor auger 54 driven by a variable speed motor 55 through a pair of sprockets 56 and 57 and a chain 58. Second feeder 53 has an opening in its bottom
40、 near the downstream end of auger conveyor 54 which is coupled to the housing 15 through a tubular member 60. Disposed above the auger conveyor 54 is a stirrer 61 that is in the form of shaft extending parallel to the shaft of the auger conveyor 54 and having a plurality of branches or arms extendin
41、g therefrom, which when the assembly is turned tends to break up any bridges or lumping of materials such as bentonite or sea coal. A pair of sprockets and a chain drive stirrer 61 form the shaft of auger conveyor 54. A third feeder 62 is disposed downstream from second feeder 53 and is generally id
42、entical for the most part to that of second feeder 53. Feeder 62 also contains an augur-type conveyor 63 driven by variable speed motor 64 with a tubular section 65 connecting the opening in the bottom of the feeder through an opening in the top of conveyor housing 15. Disposed at the bottom of the
43、housing or compartment 12 is a pair of liquid containers 70 and 71 which may contain chemicals or may contain water, depending upon the type of additive to be made to the particular sand which is being mixed. Container 70 is connected to a pump 72 through a pipe 73 communicating with container 70 an
44、d an outlet line 74 is connected to pump 72. In a similar manner, a pump 75 is connected to fluid in container 71 through a pipe 76 and the outlet of pump 75 is dispensed through a pipe or line 77. A pair of variable speed motors 80 and 81 is respectively connected to pumps 72 and 75 to dispense the
45、 liquids contained in containers 70 and 71. The variable speed motors described are conventional variable speed direct current motors and are generally 3/4 H.P. in size. Air cylinder 37 is approximately one and one-half inches in diameter and has a six inch stroke and is manufactured by Lynair under
46、 Model No. AB102-6 whereas the solenoid valve 14 is of the type manufactured by Novi, Model 25C4E. A cylindrical mixer 90 is secured to beam 13 by suitable means and has a plurality of paddles 91 carried by a shaft 92 that does the actual mixing. Shaft 92 is connected to a constant speed motor 93 by
47、 suitable means such as a coupling or clutch. Chute 16 receives materials from conveyor 17 through an opening formed in the downstream end beyond the end of conveyor 17. The lower end of chute 16 opens into a segment of mixer 90 at the upstream side thereof. Fluid-carrying pipes 74 and 77 are also c
48、onnected to mixer 90 near the downstream side of the mixer. In FIG. 2, the mixer motor drive circuit is disclosed in which a three phase 220 volt power line applies power through lines L1, L2 and L3 to mixer motor 93 through three relay contacts, all designated mixer starter contacts M1. The 220 vol
49、t line is connected to a transformer TR1 where a voltage reduction takes place in the secondary and 110 volt single phase alternating current is obtained and is applied to one line as a common or neutral line 100. A mixer motor relay M1 has its coil connected between line 100 and another line 101 connected to the secondary of transformer TR1 through a normally closed Mixer Stop pushbutton switch 102 and a normally open Mixer Start switch 103. In parallel with switch 103 is another pa
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