Patent Publication Number: US-2021162426-A1

Title: Ice Blasting Machine with Dual-Mode Operation for Water Ice and Dry Ice

Description:
TECHNICAL FIELD 
     The present invention relates to ice blasting machines. 
     BACKGROUND 
     Ice blasting machines that use either dry ice (i.e. solid carbon dioxide) or water ice as a blasting medium are known in the art. In some instances, depending on the surface to be cleaned and the substance to be removed, dry ice blasting may be more effective while in other instances water ice blasting may be more effective. In many cases, the ice blasting machine must be brought to the job site, which may mean that two different ice blasting machines may need to be carried to the job site to deal with different surfaces. 
     An improved ice blasting machine that would address this issue would be highly desirable. 
     SUMMARY 
     The following presents a simplified summary of some aspects or embodiments of the invention in order to provide a basic understanding of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key or critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some embodiments of the invention in a simplified form as a prelude to the more detailed description that is presented later. 
     Accordingly, one inventive aspect of the present disclosure is ice blasting machine comprising a crusher for crushing water ice and a crusher-activation mechanism to activate or deactivate the crusher, wherein the crusher is activated to operate in water ice mode and wherein the crusher is deactivated to operate in dry ice mode. 
     Another inventive aspect of the present disclosure is an ice-blasting method comprising activating a crusher to crush water ice when operating in water ice mode and deactivating the crusher when operating in dry ice mode. 
     Other aspects of the invention may become apparent from the description and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features and advantages of the present invention will become apparent from the following detailed description, taken in combination with the appended drawings in which: 
         FIG. 1  is a front view of a dual-mode ice blasting machine in accordance with an embodiment of the present invention. 
         FIG. 2  is a cross-sectional front view of the dual-mode ice blasting machine of  FIG. 1 . 
         FIG. 3  is a side view of a crusher with its teeth engaged for crushing water ice when operating in water ice mode. 
         FIG. 4  is a top view of the crusher of  FIG. 3 . 
         FIG. 5  is a cross-sectional view taken through section A-A in  FIG. 4 . 
         FIG. 6  is a side view of the crusher with its teeth disengaged when operating in dry ice mode. 
         FIG. 7  is a top view of the crusher of  FIG. 6 . 
         FIG. 8  is a cross-sectional view taken through section B-B in  FIG. 7 . 
         FIG. 9  depicts a worm gear style crusher retraction system in its retracted position. 
         FIG. 10  depicts the worm gear style crusher retraction system in its engaged position. 
         FIG. 11  shows the location of the worm gear style retraction system on the machine. 
         FIG. 12  depicts a lead screw style crusher retraction system in its retracted position. 
         FIG. 13  depicts the lead screw style crusher retraction system in its engaged position. 
         FIG. 14  shows the location of the lead screw crusher retraction system on the machine. 
         FIG. 15  depicts the toothed clutch engagement mechanism. 
         FIG. 16  depicts the toothed clutch disengagement mechanism. 
         FIG. 17  is an isometric view of the crusher incorporating the clutch engagement and disengagement mechanisms of  FIG. 15  and  FIG. 16 . 
         FIG. 18  depicts a reversing cam clutch disengagement mechanism. 
         FIG. 19  is an isometric view of the crusher incorporating the disengagement mechanism of  FIG. 18 . 
     
    
    
     It will be noted that throughout the appended drawings, like features are identified by like reference numerals. 
     DETAILED DESCRIPTION 
       FIGS. 1 and 2  depict a portable dual-mode ice blasting machine denoted by reference numeral  10  in accordance with an embodiment of the present invention. The dual-mode ice blasting machine  10  in the illustrated embodiment comprises a frame  12  and wheels  14  so that ice blasting machine is portable. In the illustrated embodiment, the ice blasting machine does not have an internal ice maker. Rather, ice is loaded via a hatch  16  on the top surface of the ice blasting machine. The ice blasting machine includes an internal crusher  18  that is configured to receive large blocks or chunks of ice and is able to crush the ice down to a useful size, i.e. a size that enables entrainment into a high-speed stream of pressurized air. The ice blasting machine is considered to be “dual-mode” because it is able to independently blast a surface with dry ice and water ice through either a common outlet hose or a pair of outlet hoses, i.e. a first hose dedicated for outputting an airstream carrying dry ice and a second hose dedicated for outputting an airstream carrying water ice. The airstream velocity may be manually or automatically adjustable by regulating the air source, e.g. by controlling an air pump or regulating a valve from a compressed air tank. The mass flow rate of ice may also be adjustable. 
       FIG. 2  shows the location of the crusher  18 . The crusher in the illustrated embodiment is a V-shaped crusher that is composed of a pair of jaws open and close to crush chunks of ice into smaller pieces of ice. The hopper rests on an agitator  20  or agitation system. The V-shaped crusher is also disclosed in Canadian Patent No. 2,964,016, which is hereby incorporated by reference. 
     In at least some embodiments, the crusher is activated when operating in water ice mode to enable the ice blasting machine to crush large chunks of ice into smaller bits of ice whereas the crusher is deactivated when operating in dry ice mode. 
     For the purposes of this specification, the expression “water ice mode” means that the machine is blasting only water ice particles. 
     For the purposes of this specification, the expression “dry ice mode” means that the machine is blasting only dry ice particles. 
     It will be appreciated that the ice blasting machine may have a switch, controller, programmable logic controller or processor to switch, either manually or automatically, between water ice and dry ice modes. The switch may be disposed on the handheld nozzle or alternatively on the frame. 
       FIGS. 3-5  depict the crusher with its teeth engaged when operating in water ice mode. The mechanism includes a hopper agitation cam which alternately lifts and drops the hopper to keep the media (ice) moving in the hopper. In water ice mode the crusher teeth are engaged with the drive motor and move cyclically to crush the ice into sufficiently small pieces to prevent clogging in the discharge hose. 
       FIGS. 6-8  depict the crusher with its teeth retracted or disengaged when operating in dry ice mode. In dry ice mode, the crusher teeth are disengaged from the motor and so do not move, i.e. are immobile. In at least this embodiment, this disengagement is necessary as the dry ice will fill the space between the crusher and will prevent any motion, thereby leading to eventual motor burnout or chain skipping. One side of the crusher teeth is retracted in order to provide an unrestricted path from the hopper to the feeder. The agitation cam system is keyed to the motor driveshaft and thus continues to operate in dry ice mode. 
     To activate and deactivate the crusher, the ice blasting machine includes a crusher-activation mechanism. Different embodiments of the crusher-activation mechanism are disclosed below. 
       FIGS. 9-11  depict a worm gear style crusher teeth retraction mechanism with an integral servomotor. This is one example of a crusher-activation mechanism for retracting the crusher teeth. The servomotor  30  turns a worm gear  32  which in turn acts upon a fan plate  34  which has mating gear teeth machined into the outer radius. This moves the slider backwards and forwards. 
       FIGS. 12-14  depict a lead screw style crusher tooth retraction mechanism having a lead screw  42  and an integral servomotor  30 . The crusher teeth slider guide  44  can change its angle by turning the lead screw. This moves the slider plate forwards or backwards. Using this mechanism the crusher teeth can be completely pulled out of the way, or partially retracted to allow larger ice particles to fall through in water ice mode. 
       FIG. 15  depicts details of a toothed clutch sprocket engagement mechanism on the crank lobe. The sprocket  50  at the far left rides on a first clutch jaw  52  which can freewheel on the crank shaft  54 . The second clutch jaw  56  is keyed to the crank shaft and can slide axially to engage the first jaw using the attached shifter levers. 
       FIGS. 16-17  depict a crusher disengagement system belt arrangement for toothed clutch disengagement system. The crusher has two crusher sprockets  70 . The drive motor is directly chained to the feeder sprocket and to a freewheeling clutch on one crusher crank lobe. There is a sliding clutch engagement system on this crank lobe that can be in two positions. The first position locks the freewheeling sprocket to the crank lobe and allows the drive motor to turn the crusher. The second position disengages the freewheeling sprocket which allows the drive motor to turn without engaging the crusher teeth. There is a second chain connecting the two crusher teeth shafts which allows there to be only one clutch system on one of the crusher shafts to engage both crusher teeth simultaneously. 
       FIGS. 18-19  depict a crusher disengagement system belt arrangement for reversing cam clutch disengagement system. The twin crusher sprockets  70  ride on cam clutch bearings and so will only engage with the crank lobes when turning in one direction. There is a second timing chain to maintain the relative phase angle between the respective crusher sides. In this arrangement the crusher will move when the motor is turning forwardly in water ice mode. The crusher sprockets will freewheel when the motor is running in reverse and the crusher teeth will not move, which is necessary in dry ice mode. 
     The various embodiments of the dual-mode ice-blasting machine disclosed in this specification enable a user to perform a novel ice-blasting method. The method entails activating a crusher to crush water ice when operating in water ice mode and deactivating the crusher when operating in dry ice mode. 
     It is to be understood that the singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a device” includes reference to one or more of such devices, i.e. that there is at least one device. The terms “comprising”, “having”, “including”, “entailing” and “containing”, or verb tense variants thereof, are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of examples or exemplary language (e.g. “such as”) is intended merely to better illustrate or describe embodiments of the invention and is not intended to limit the scope of the invention unless otherwise claimed. 
     While several embodiments have been provided in the present disclosure, it should be understood that the disclosed devices and systems might be embodied in other specific forms without departing from the scope of the present disclosure. The present examples are to be considered as illustrative and not restrictive, and the intention is not to be limited to the details given herein. For example, the various devices and systems may be combined or integrated in another system or certain features may be omitted or not implemented. 
     In addition, techniques, systems, subsystems, and methods described and illustrated in the various embodiments as discrete or separate may be combined or integrated with other systems, modules, techniques, or methods without departing from the scope of the present disclosure. Other items shown or discussed as coupled or directly coupled or communicating with each other may be indirectly coupled or communicating through some interface, device, or intermediate component whether electrically, mechanically, or otherwise. Other examples of changes, substitutions, and alterations are ascertainable by one skilled in the art and could be made without departing from the inventive concept(s) disclosed herein. 
     This invention has been described in terms of specific embodiments, implementations and configurations which are intended to be exemplary only. Persons of ordinary skill in the art will appreciate, having read this disclosure, that many obvious variations, modifications and refinements may be made without departing from the inventive concept(s) presented herein. The scope of the exclusive right sought by the Applicant(s) is therefore intended to be limited solely by the appended claims.