Not Applicable.
Not Applicable
1. Technical Field of the Invention
The present invention relates generally to an abrasive blasting machine, and more particularly to an easily attachable/detachable entrance vestibule for an abrasive blasting machine that allows a long work-piece to extend through the entrance vestibule for abrasive treatment while at the same time mitigating abrasive/particulate escape from the blasting machine.
2. Description of the Related Art
Blast cabinets are well-known in the art and are typically utilized to clean or generally prepare surfaces of a work-piece by directing high pressure fluid containing abrasive blast media or blast particulate toward the work-piece. The abrasive blast particulate is typically a relatively hard material such as sand, sodium bicarbonate (i.e., baking soda), metallic shot or glass beads although many other materials may be selected for use as the blast particulate.
The blast cabinet typically includes a housing supported on legs, wherein the housing typically defines a generally air tight enclosure having a pair of arm holes with gloves hermetically sealed thereto such that an operator may manipulate a blast hose and/or the work-piece for blasting thereof within the enclosure. The blast hose is configured to direct the high pressure fluid such as air carrying the blast particulate at high velocity toward the work-piece surfaces. The blast cabinet typically includes a transparent window to allow the operator to manipulate the work-piece and to visually observe the progress of the blasting operation.
During blasting, the blast particulate bounces off of the work-piece and is generally violently thrown about within the enclosure. Given that the blasting generally is performed in an air-tight enclosure, the particulate remains within the blast cabinet during the blasting operation. A blower may be connected to the blasting machine to create a negative pressure within the enclosure to collect the particulate within a hopper. The collected particulate may be re-circulated through the system and used as an abrasive during subsequent blasting operations.
In most conventional blasting machines, the containment of the particulate is made possible by forming the air-tight enclosure during blasting operations. In this regard, most blasting machines include a door that may be opened to allow for insertion of the work-piece into the machine, wherein the door is configured to form an air-tight seal with the housing when the door is closed.
The above-described configuration may be feasible for smaller work-pieces that can fit within the enclosure defined by the blasting machine. However, larger pieces, particularly longer pieces, may not be able to fit within the blasting machine so that the door can close to define an air-tight enclosure. Furthermore, if the door is left open, an air-tight enclosure will not be formed, which disrupts the flow characteristics and negative pressure within the blasting machine and dangerously allows the particulate to escape from the machine during blasting operations.
Therefore, there is a need in the art for a device that allows larger work-pieces to be inserted within a blasting machine while at the same time preventing particulate from escaping.
The present invention specifically addresses and alleviates the above-identified deficiencies in the art. There is provided an entrance vestibule that is designed to be easily attachable and detachable to a conventional blasting machine for blasting work-pieces that are longer than the inner blasting chamber of the blasting machine. In this regard, the entrance vestibule is uniquely designed to attach to the blasting machine adjacent an existing opening formed on the blasting machine (such as the door opening). The entrance vestibule additionally includes an entrance channel sized to allow the larger work-pieces to easily enter the inner blasting chamber. The entrance channel is additionally configured to allow air to flow therethrough so as to urge particulate from escaping from the blasting machine through the entrance channel.
According to one embodiment, the entrance vestibule includes a base plate having an inner surface, an opposing outer surface and a base plate opening extending from the inner surface to the outer surface. The base plate is configured to be engageable with the housing to substantially cover the housing opening. An extension member is connected to the base plate and includes a first end and a second end to define an extension member length therebetween. The extension member defines an entrance channel extending from the first end to the second end and is aligned with the base plate opening to allow for passage of a work-piece into the inner blasting chamber through the entrance channel and base plate opening. The entrance channel is configured to allow ambient air to enter the inner blasting chamber through the entrance channel. The extension member defines a length sufficient to maintain the negative pressure within the inner chamber to mitigate escape of the particulate through the entrance channel during operation of the abrasive blasting machine.
It is contemplated that one embodiment of the entrance vestibule may include pin hinges to easily connect with a housing having corresponding pin hinges that allow the blast cabinet door to be easily removed therefrom. According to another embodiment, the entrance vestibule is configured to engage with the blast cabinet housing without removal of the blast cabinet door.
The entrance vestibule may also be configured for use with a support track which is connected to the entrance vestibule and extends into the blast cabinet to support the workpiece during blasting operations.
The entrance vestibule may also include a baffle to control the size of the entrance channel opening to manage the airflow therethrough. The entrance vestibule may also be configured for use with a block-off plate to control the amount of air that enters the blast cabinet through the air inlet built-in the blast cabinet.
The present invention is best understood by reference to the following detailed description when read in conjunction with the accompanying drawings.
These as well as other features of the present invention will become more apparent upon reference to the drawings wherein:
Common reference numerals are used throughout the drawings and detailed description to indicate like elements.
The detailed description set forth below is intended as a description of the presently preferred embodiment of the invention, and is not intended to represent the only form in which the present invention may be constructed or utilized. The description sets forth the functions and sequences of steps for constructing and operating the invention. It is to be understood, however, that the same or equivalent functions and sequences may be accomplished by different embodiments and that they are also intended to be encompassed within the scope of the invention.
Referring now to the drawings, wherein the showings are for purposes of illustrating a preferred embodiment of the present invention only, and not for purposes of limiting the same, various aspects of the present invention are directed toward an entrance vestibule 10 configured to be easily attached to an abrasive blasting cabinet/machine 12 adjacent an existing opening formed on the blasting machine 12 (such as the door opening) to perform abrasive blasting on panels that are larger/longer than the inside width of the blasting machine 12. The entrance vestibule 10 is additionally configured to be easily removed from the blasting machine 12 at the conclusion of the blasting operations. The entrance vestibule 10 includes an extension member 14 defining an entrance channel 16 through which the panels 18 may be inserted into the blasting machine 12. The entrance vestibule 10 is additionally configured to keep abrasive or particulate within the machine 12, i.e., to prevent particle escape, during operation. Along these lines, the entrance vestibule 10 is configured to work in connection with the blasting machine 12 to create the air velocity necessary to maintain the abrasive particulate within the blasting machine 12.
Referring now specifically to
The blasting machine 12 is configured to recycle the abrasive particulate after it is emitted by the blasting stylus 34. In this regard, the blasting machine 12 creates an air flow which directs the abrasive particulate toward a collection hopper which then feeds the particulate back to the blasting stylus 34. The air flow necessary to create the abrasive recycling system may employ a suction device and an air inlet to maintain a desired negative pressure within the inner blasting chamber 22 during the blasting operation. Thus, in order to maintain the requisite negative pressure, the door 38 connected to the housing 24 typically forms a fluid tight seal therebetween.
Various aspects of the present invention are directed toward adapting the entrance vestibule 10 for use with existing blasting machines 12. In this regard, the entrance vestibule 10 is configured to easily connect to the housing 24 in the same manner as the door 38. It is understood that there are various types of blasting machines, including blasting machines with easily removable doors (i.e., doors on a pin hinge) and blasting machines with generally non-removable doors. Accordingly, as will be explained in more detail below, there are various embodiments of the entrance vestibule which are configured for use with different types of blasting machines, i.e., blasting machines having easily removable doors and generally non-removable doors.
The entrance vestibule 10 also includes a base plate 46 that is similar in size and shape to the door 38. In addition, due to the pivotal hinge connection with the housing 24, the base plate 46 may pivot between an open configuration wherein the door opening 36 is uncovered (see
The base plate 46 includes an inner surface 48 and an opposing out surface 50. When the base plate 46 is in the closed position, the inner surface 48 faces toward the inner blasting chamber 22 and the outer surface 50 faces away from the housing 24. The base plate 46 additionally includes a base plate opening extending from the inner surface 48 to the outer surface 50 to allow a work-piece 18 to be advanced through the base plate 46. An extension member 14 connected to the base plate 46 adjacent the base plate opening and defines the entrance channel 16, which also extends through the base plate opening. The extension member 14 includes a first end 52 and an opposing second end 54 to define an extension member length therebetween. It is contemplated that various entrance vestibules 10 may define different lengths of the extension member 14 depending on the size of the work-piece 18, and the size needed to keep particulate from escaping through the entrance channel 16. For instance, the extension member 14 may define lengths of 6 inches, 12 inches, 18 inches. In general, the extension member 14 must have a physical length long enough to create the entrance air velocity inside the entrance channel 16 capable of preventing abrasive particulate escape during operation of the blasting machine 12. Thus, the length of the extension member 14 is used to turn the abrasive particulate around and keep the particulate from leaving the inner blasting chamber 22. In this regard, the entrance channel 16 not only serves as a pathway through which a work-piece 18 may be inserted into the inner blasting chamber 22, it also serves as an air inlet used to operate and run the machines particulate collection system by maintaining negative pressure within the inner blasting chamber 22.
According to one implementation, the velocity inside the entrance channel 16 must be approximately 2,000 ft. per minute or greater to effectively maintain abrasive particulate within the inner blasting chamber 22 during operation of the machine 12. This air velocity is created by the machine dust collector blower, i.e., the suction device described above. The length of the extension member 14 is used to create the necessary air direction length to reverse abrasive particles and keep the abrasive particles inside the machine 12 during operation. The air velocity is calculated using the extension member 14 transverse cross sectional area, measured in percentage of one square foot, which is divided into the suction volume generated by the dust collector blower, which may be measured in cubic feet per minute. As the extension member length is reduced, i.e., from 12 inches to 6 inches, the air velocity inside the entrance channel 16 must increase.
Given that the entrance channel 16 allows outside air to enter the inner blasting chamber 22, the fluid dynamics inside the inner blasting chamber 22 may be disturbed. In particular, during standard operating conditions, i.e., during operation of the blasting machine 12 with the original door which seals the inner blasting chamber 22, the blasting machine 12 creates a negative pressure to urge the abrasive toward the collection hopper. In this regard, blasting machine 12 may include a built-in fluid inlet which delivers air into the inner blasting chamber 22, and a built-in fluid outlet which draws air from the inner blasting chamber 22 to urge the abrasive and particulate thereto. When the standard door is replaced with the entrance vestibule 10, the entrance channel 16 serves as an additional air inlet which changes the flow characteristics and negative pressure within the inner blasting chamber 22. Thus, one aspect of the present invention is directed toward controlling the airflow and pressure within the inner blasting chamber 22 to keep the abrasive/particulate from escaping through the entrance channel 16.
According to one embodiment, the entrance vestibule 10 includes a baffle 56 (see
The baffle 56 may be moved between an open position and a closed position relative to the extension member 14. When the baffle 56 is in the open position more air can flow through the entrance channel 16 than when the baffle 56 is in the closed position. In this regard, the baffle 56 blocks at least a portion of the entrance channel opening when the baffle 56 is in the closed position, while in the open position, the baffle 56 preferably does not block the entrance channel opening. Thus, the user may selectively move the baffle 56 between the closed and open positions to control the velocity of air flowing through the vestibule 10 to prevent abrasive escape.
According to another implementation of the present invention, the airflow may also be controlled by the use of a block-off plate 58 (see
The block of plate 58 may define various shapes and sizes and may be formed of a metallic material or other materials known by those skilled in the art. The block off plate 58 may be configured to pivot, slide, translate, rotate, etc. relative to the built-in air inlet to control the air flow through the air inlet. The block off plate 58 may be connected to a control handle on the outside of the machine 12 to allow the user to move the block off plate 58 during operation of the machine.
Referring now specifically to
The support track body 62 is connected to an adjustable leg 70 which props up the support track 60. The adjustable leg 70 includes a threaded post 72, a foot member 74, and a connection bracket 76. The connection bracket 76 is connected to the support track body 62 via mechanical fasteners, such as a nut and bold, rivet, or the like. The connection bracket 76 may be threadably engaged with the threaded post 72 to allow for height adjustment of the support track body 62. In this regard, the threaded post 72 may be rotated to achieve such height adjustment, i.e., rotation in a first direction to increase the height, and rotation in an opposing second direction to decrease the height. The foot member 74 is connected to the threaded post 72 and is configured to rest on a base surface, such as the grate shown in
The support track 60 may also be configured to hold or maintain the work-piece 18 in an upright configuration during blasting operations. Thus, the user may not have to hold the work-piece 18 with one hand and perform the blasting operations with the other hand. Rather, given that the work-piece 18 is maintained in a work-ready position independent of user assistance, the user may use both hands for the blasting operation. The support track 60 may support the work-piece 18 in the upright configuration by the insertion of the work-piece 18 within the support track channel. In this regard, the support track channel may define a depth which holds the work-piece in the upright configuration.
For heavier work-pieces, the support track 60 may include an auxiliary support bracket 78 connected to the support track body 62 and configured to support the work-piece 18 in the upright configuration. According to one embodiment, the auxiliary support bracket 78 includes a pair of mounting posts 80 and a moveable roller assembly 82 connected thereto. The roller assembly 82 includes an assembly bracket 84 and a pair of rollers 86 connected to the assembly bracket 84. The assembly bracket 84 includes a pair of sleeves 88 sized to receive a respective one of the mounting posts 80 to allow the assembly bracket 82 to be slidable along the length of the mounting posts 80. A screw or other mechanical fastener may be used to selectively secure the assembly bracket 82 in position along the mounting posts 80.
The auxiliary support bracket 84 is positioned such that the pair of rollers 86 are position in a tangentially aligned configuration relative to the work-piece 18 when the work-piece 18 is disposed within the support channel. In other words, the rollers 86 are positions such that the rollers 86 engage with the work-piece 18 in a common plane.
As previously mentioned, it is important to regulate airflow into the inner blasting chamber 22 to keep abrasive particles from exiting machine 10. In some blasting machines 12, particularly those which output less than 16 cubic feet/minute from the nozzle/stylus 34, open operator access ports may be used. When the entrance vestibule 10 is connected to the machine 12, it may be necessary to attach gloves 90 to the operator access ports 30, 32 to restrict air flow into the inner blasting chamber 22 through the operator access ports 30, 32. The gloves 90 may substantially restrict airflow through the operator access ports 30, 32 and may be configured to create a fluid-tight seal with the body of the blasting machine 12 to prevent air from entering the inner blasting chamber 22 and to prevent abrasive from exiting the inner blasting chamber 22.
The entrance vestibule 10 described above is configured for use with a blasting machine 12 having an easily removable door 38. However, it is understood that other blasting machines may include a door that is not easily removable, particularly older blasting machines. Therefore, another embodiment of the present invention relates to an easily attachable/detachable entrance vestibule configured for use with a blasting machine, wherein the blasting machine door remains connected to the blasting machine during usage of the entrance vestibule.
Referring now specifically to
The entrance vestibule 100 includes a base plate 106 having an inner surface 108 and an opposing outer surface 110, with an opening 112 formed within the base plate 106 and extending from the inner surface 108 to the outer surface 110. The entrance vestibule 100 further includes an extension member 114 connected to the base plate 106 and defining an entrance channel 116 that passes through the opening 112. In this regard, when the entrance vestibule 100 is connected to the blasting machine 102, the entrance vestibule 100 operates in a similar fashion to the entrance vestibule 10 discussed above.
The primary distinction between the entrance vestibule 100 and the entrance vestibule 10 is the mechanism by which the entrance vestibule 100 connects to the blasting machine 102. In particular, the entrance vestibule 100 is configured to engage with the blasting machine 102 to create a substantially fluid tight seal therebetween without removing the door 104. In this regard, the base plate 106 is configured to fit over the opening 115 (see
Along these lines, the entrance vestibule 100 connects to the blasting machine by a lower lip member 116 and an upper locking mechanism 118 each being connected to the base plate 106. The lower lip member 116 extends from the base plate 106 to define a channel 120 therebetween. The lower lip member 116 is configured to fit into the opening 115 and extend over a portion of the blasting machine wall 122 (see
Although not shown, it is contemplated that the support track 60 described above may be used with the entrance vestibule 100, as well as with the entrance vestibule 10. Furthermore, the baffle 56 and block-off plate 58 described above for achieving certain fluid characteristics while using the entrance vestibule 10 may also be used with the entrance vestibule 100.
Referring now specifically to
Additional modifications and improvements of the present invention may also be apparent to those of ordinary skill in the art. Thus, the particular combination of components and steps described and illustrated herein is intended to represent only certain embodiments of the present invention, and is not intended to serve as limitations of alternative devices and methods within the spirit and scope of the invention.