Abstract:
An air cooled internal combustion engine has the usual intake radiator housing in front of its suction fan. A generally frustoconical body is mounted for rotation in front of the radiator. The body is made up of radially extending deflector fins extending outwardly in convergent relationship and spaced uniformly peripherally apart to provide elongate air entrance slits between them. Mechanism drives the body in rotation at a speed to deflect particles seeking to enter the slits without materially decreasing the rate of air flow created by the suction fan.

Description:
This application claims the priority of provisional application Ser. No. 60/158,982 filed Oct. 12, 1999. It relates to air cleaner radiator suction fan assemblies which rotate in advance of the radiator and the suction fan behind it to prevent bark particles, dirt particles, sawdust, needles, and other foreign material, which can become entrained in an air stream, from entering the radiator. The invention is particularly useful in atmospheres wherein the particles or material principally include particles of the type mentioned. 
    
    
     BACKGROUND OF THE INVENTION 
     When engine radiators become clogged with debris, the radiator becomes inoperative or, partly so, to the extent that the engine overheats. In the past, stationary mesh screens have been used in advance of the radiator when an engine is being used to power a machine at a worksite in which “dirty air” might create problems, but these screens have tended to clog and require frequent cleaning, particularly in operations in which entraining matter is created at the worksite. 
     Other attempts to solve the problem have involved the use of spinning perforated or mesh cylinders to admit air to radiators of the type which typically are used on agricultural machinery. These, also, tend to become easily clogged and to require frequent and difficult manual cleaning of the cylinders and radiator. 
     SUMMARY OF THE INVENTION 
     The present invention is concerned with a frustro-conical tubular device having truly radial fins which do not operate as fans to suck air, and accordingly entrained particles, into the device. The air cleaner of the present invention is in the form of a right circular cone frustrum having a slitted surface area. The frustro-conical member may be driven by its own hydraulic, or other suitable, motor at a speed different than the speed of rotation of the suction fan. The frusto-conical member is driven at a speed such as not to materially reduce the volume of air being drawn in through the frustro-conical member by the suction fan. 
     One of the prime objects of the present invention is to provide an air cleaner assembly which can be readily attached to the radiator frame of a radiator having a suction fan disposed behind it which is driven by the diesel or other internal combustion engine which the radiator protects. 
     A further object of the invention is to provide an air cleaner radiator fan assembly wherein the controlled air flow volume into the radiator is not diminished, but foreign matter which might entrain in the air flow is deflected and does not enter the air cleaner. 
     Another object of the invention is to provide a cleaner assembly which avoids clog problems and the frequent radiator dismantlement and cleaning associated therewith. 
     Still, another object of the invention is to provide an air cleaner attachment for engine radiator suction fans which is designed to prevent undue shutdown of the machinery which the engine is operating. 
     A further object of the invention is to provide a relatively economical assembly of the character mentioned which can be relatively economically fabricated, and yet is reliable and durable, and requires virtually no maintenance. 
     Other objects and advantages of the invention will become apparent with reference to the accompanying drawings and the accompanying descriptive matter. 
    
    
     GENERAL DESCRIPTION OF THE DRAWINGS 
     The presently preferred embodiment of the invention is disclosed in the following description and in the accompanying drawings, wherein: 
     FIG. 1 is a schematic side elevational view of the engine, suction fan, engine radiator and air cleaner assembly, with portions of the suction fan and radiator housings broken away to show the fan blades and radiator fins respectively; 
     FIG. 2 is a schematic perspective exploded view showing various elements of the overall assembly; 
     FIG. 3 is a perspective elevational view, more particularly illustrating the conical member which spins on the radiator; 
     FIG. 4 is a top plan view illustrating a punched strip used in the construction of the conical member; 
     FIG. 5 is an enlarged fragmentary view, of a portion thereof; 
     FIG. 6 is an enlarged fragmentary elevational view illustrating particularly the manner in which the fins formed extend marginally along the slots punched in the strip; 
     FIG. 7 is a schematic perspective exploded view showing various elements of another embodiment; and 
     FIG. 8 is an enlarged schematic perspective view of a seal member which is employed. 
    
    
     DETAILED DESCRIPTION 
     Referring now, more particularly, to the accompanying drawings and, in the first instance particularly to FIGS. 1 and 2, an engine, generally shown at E, has a fan drive shaft  10  shown as operating a belt  11  on a suitable sheave which drives a sheave  13  on a fan drive shaft  14 . The suction fan, generally designated  15 , is fixed on the shaft  14 . The suction fan  15 , as usual, has fan blades  16 , secured on a hub  17 , for creating a suction to pull air in through a radiator, generally designated R, having the usual radiator fins  18 . The intake radiator fins  18 , as usual, are fixed within a surrounding housing  19 . 
     Provided to mount on the front face of radiator housing  19  is an air cleaner assembly, generally designated  20 , which includes a stationary mount plate  21  and a protective, stationary guard housing  23  for a spinning member  22 . The system&#39;s mount plate  21  includes a circular opening  21   a  (FIG. 2) surrounded by an outwardly extending circular flange  24 . Spanning the opening  21   a  are spaced apart bars  25  for mounting a motor housing or cage, generally designated  26 , which incorporates a front plate  27  with an opening  28  for admitting a drive shaft  29 . The motor  30 , which may be a small hydraulic or other type of motor, has a drive shaft  31 , which is provided with a splined connection to a coupling sleeve  32  provided on the rear end of shaft  29 . Motor  30  may be serviced by a suitable pump and hydraulic system of conventional and well-known character. 
     Within the frustro-conical member  22 , which mounts within flange  24  and will now be more particularly described, is a shaft mount system, generally designated  33  (FIG.  3 ), comprising spokes  33 a secured to a hub member  34 . The hub  34  mounts a shaft drive bushing  35  (FIG. 2) and the end of the conical member  22  is provided with a front plate  36  with a hub ring  37  which receives shaft bushing  38 . The conical member drive shaft  29  extends through the bushings  35  and  38  through a bearing  39  received in an opening  40  provided in the front wall of protective guard housing  23 . Guard housing  23 , which can be mounted to plate  21 , may be, as shown, simply provided with top, bottom, and side mesh walls  41  and it will be seen that the front wall also includes a mesh portion  42 . 
     Turning now more particularly and once again to FIG. 3, it will be seen that the conical member or body  22  includes an enlarged open rim rear or inner end band  43  and a reduced diameter open rim outer front end band  44 . Received within the rim  44  is the front plate  36 , which has a rigid peripheral flange fitting within the member  44 . Also, intermediately provided on member  22 , is a rigid rim band  45  to provide support for outwardly converging peripherally spaced, relatively thin elongate rigid fins  46  (between rigid bands  43  and  45 ) and  47  (between rigid bands  44  and  45 ). Typically, fins  46  and  47  will be 0.0598 thousandths of an inch in peripheral width and be uniformly circumferentially spaced apart a distance of three-eighths of an inch (0.375). The typical overall radial extent of inwardly divergent-in-depth fins  46  and  47  will typically be three-eighths of an inch to a quarter of an inch and the fins  46  and  47  will project radially outwardly and inwardly beyond bands  43  and  45 , and bands  44  and  45 , slightly less than half that much. 
     It is believed important that the surface area of the conical periphery  22  be related to the surface area of the radiator fin area  18 , and it has been found that the cleaner operates efficiently when the peripheral surface area of the cone is generally twice the surface area of the radiator face  18 , and the speed of revolution of the member  22  is controlled with respect to the surface area of the cone. Speeds of rotation in the range 700-1,100 r.p.m. are believed most efficient. When the mean perimetral speed of the member  44  at intermediate band  45  in terms of feet per minute is approximately the same as the speed of the air stream entering the radiator R, very good results are obtained. The air speed through the radiator as measured by an anometer will not be materially reduced by the presence of the device disclosed. 
     THE OPERATION 
     In operation, with the device assembled as shown in FIG. 1, air with entrained particulate material enters the guard housing  20  through the mesh walls  41  or  42  which do not significantly prevent the entry of foreign material. When this air stream with entrained dust and particles reaches the member  22 , the truly radial fin blades  46  and  47 , which have portions projecting radially inwardly and outwardly, as shown in FIG. 6, to define radially elongate, air entrance slits S between the fin blades  46  and  47 , prevent the unwanted particles from entering the virtually open, tubular interior of conical member  22  by deflecting the particles from the air flow. The cleaned air entering the member  22  proceeds through to the radiator in the usual fashion and is sucked through the radiator by the suction fan blades. It is important that the turbulence at members  44 ,  45  and  43  be minimal and this is achieved by the conical shape of member  22  with its larger inner end journaled adjacent to the radiator. The suction created by the suction fan blades is greatest at the large diameter rim  43  where the surface speed of revolution is greater and has dissipated somewhat at the lesser diameter rim  44  where the surface speed of revolution is reduced. A balance is achieved with a frusto-conical angle of inclination between 15 and 45 degrees when air flow volume into the member  22  through uniform width slits S is substantially the same as air flow volume through a radiator with no unit  22  attached. The air flow through the radiator with the unit in place and without it, is checked in this regard. 
     In a prototype unit, when the overall surface area of the conical member  22 , including both the width of the fins  46  and  47  and the gaps or slits S between the fins  46  and  47  was a thousand inches squared and the radiator surface area, including fins  18  and gaps, was 506 inches squared, the speed of air flow through the radiator R, both with the unit attached and without the unit, was 2,200 feet per minute, and with the unit  22  being driven at 700 rpm&#39;s, excellent cleaning results were achieved. In this example, the rim speed at member  44  was 2,200 feet per minute and the rim speed at member  43  was 4,600 feet per minute. The frusto-conical angle was 22° and the large diameter and reduced end diameters were 25 and 12 inches, respectively. When the unit was driven at 800 rpm&#39;s, the rim speed at member  44  was 1,885 feet per minute and the rim speed at the band  43  was 3,942 feet per minute. The cleaning result when the unit was driven at 600 rpm&#39;s was not as good, but at 800-1,100 rpm&#39;s was very good in the sense that little difference from 700 rpm&#39;s, in terms of cleaning the airstream, was noted. 
     The goal of providing the attachment unit in the combination of elements was accomplished by deflecting particulate matter from entering the radiator without reducing the air flow to and through the radiator. For example, with sawdust, close to 100 percent has been eliminated from the air stream. 
     METHOD OF CONSTRUCTION 
     In FIG. 4, a relatively thin strip of flat sheet metal  48  is shown as in its configuration prior to being bent to frusto-conical shape and welded or otherwise fixed at its ends to form member  22 . As shown in FIG. 4, a series of I-shaped uniform width openings  49  and  49   a  are punched in the flat sheet  48  between portions  44   a ,  45   a , and  43   a , which will form the peripheral bands  44 ,  45  and  43 . 
     FIG. 6 shows the fins  46  and  47  formed when the reduced width somewhat ductile end portions  46   a  and  47   a  of the material remaining between openings  49  and  49   a  are twisted ninety degrees to form the radially projecting, inwardly diverging-in-depth, fins  46  and  47 . Thereafter, of course, the strip  48  is bent to tubular shape and the ends fixed (i.e., welded) together to form the outer periphery of the member  22 , and the plate  36  is assembled in place and fixed. The bushings  35  and  36  are provided for the shaft  29  and the shaft  29  is connected to motor  30  and extended to bearing  40  in the guard housing  23 , after which the entire unit, utilizing mount plate  21  can be mounted to the radiator frame  19 . 
     In FIGS. 7 and 8, we have shown a modified form of the invention in which the same numerals and letters have been used to describe the various common parts of the mechanism for the sake of convenience. 
     One of the differences is that the hydraulic motor  30  is mounted on the front or outer end of the device, on the stationery guard housing  23 . Accordingly, the former cage  26 , which mounted to the plate  21  on bars  25 , is eliminated, and a bearing plate  50  removably fixes to the plate  51  carried by the plate  21  to carry the inner end of shaft  29 . 
     The shaft mount system  33 , which similarly has spokes  33   a  carrying hub member  34 , is provided on the body member  22  and receives the drive bushing  35 . The frusto-conical member  22  is provided with a front plate  36  which receives shaft bushing  38  in hub ring  37  and the end  29   a  of shaft  29  passes through a bearing plate  52  and couples to the motor shaft  30   a . With the motor  30  supported on the back wall  23   a  of the housing  23 , the task of connecting hoses for carrying hydraulic fluid to and from the motor  30  is simplified. 
     Whereas previously the band  44  of spinning member  22  rotated directly on the flange  24  of plate  21 , in the new version a commercially available cup seal (FIG.  8 ), generally designated CS, is fixed within inner band  43 . The seal CS includes a ring  53  which is received on the flange  24  and has a thick metal brush  54 , comprising fine flexible metal fibers, engaging the plate  21 . It has been found that the efficiency of the unit is increased with the seal CS in place to prevent air, which has entered the spinning member  22  and is flowing to the radiator fins  18 , from escaping at the periphery of the unit  22  past rim  43 . 
     The prototype unit constructed according to FIGS. 7 and 8 was larger in diameter and operated successfully. The new member  22  had a diameter of  43  ½ inches at band  43 , a diameter of 25 inches at band  44 , and a diameter of 34 inches at band  45 . The spacing between fins was maintained at ⅜ of an inch and the unit was run at a speed of 1,100 rpm. 
     It is to be understood that the disclosed embodiment is representative of a presently preferred form of the invention and that others that accomplish the same function are incorporated herein within the scope of the patent claims.