Abstract: A protection system for a conveyor for items, such as food items, is provided to keep the conveyor free from bacteria and other contaminants which may accumulate and build-up on the conveyor track and track traversing components. The protection system includes a shroud surrounding the conveyor to which pressurized, bacteria-free air is fed. A preferred bacteria removal unit is a filtration unit to filter bacteria from the ambient air. Herein, a combination filter and blower unit is disclosed which finely filters ambient air, preferably down to 3 microns, and pressurizes the air and blows it into an air manifold connected to the shroud by a series of air ducts. The shroud walls cooperate to form a slot through which the meat hangers can extend and for allowing the clean air in the shroud to be continually flowed therethrough and circulated around the conveyor components.

Abstract: A method of electrostatically painting and an apparatus for producing an electric field within a booth includes a paint spray gun charged to a first potential and a target to be painted to a second potential with one of the panels in the booth charged to a third potential intermediate the first potential and the second potential to repel paint particles away from the panel. The paint particles and the panels are charged to the same polarity and the target is of the opposite polarity. The panel is usually a wall, a ceiling and/or a conveyor protection housing within the paint spray booth. The preferred panel comprises an outer insulating layer of plastic, glass or porcelain that is easily wiped of paint and an interior, electrically-conducting layer such as a thin sheet of aluminum. Variations of the panel include a version which is completely enclosed in plastic and a version which is bonded to plastic.

Abstract: A spray booth is provided with inexpensive, disposable pre-baffles which collect overspray thereon prior to the overspray reaching the filtering stages. The preferred disposable pre-baffles are made of paperboard and after being coated with overspray for a short period, e.g., one week, are easily detached and replaced. The paint on the disposable pre-baffles can be baked to convert the paint and the baffle from a hazardous to a non-hazardous waste. The pre-baffles may collect as much as 80% of the overspray, some of which may be collected and re-used, and reduces the amount of sludge, filter cleaning, chemicals used in the reservoir water, and the emissions. Thus, the overall savings easily overcome the expense of replacing the disposable pre-baffles.

Abstract: An air curtain conveyor protection system that prevents airborne particles from entering a slot through which the product support members extend from the conveyor mechanism housing into the product treatment booth. A continuous stream or curtain of high velocity air flows across the slot in the conveyor housing, exiting from an outlet or supply nozzle formed by a plenum on one side of the slot and entering into a suction nozzle formed on the opposite side of the slot by a second plenum. A fan or blower is associated with each plenum to force ambient air through the supply nozzle and to draw air through the suction nozzle. Ambient air flowing between the nozzles forms an air curtain across the slot to prevent ingress of the deleterious atmosphere in the product treatment booth into the conveyor housing.

Abstract: A spray booth includes an air cleaning apparatus providing an air intake beneath its floor, and provides air curtains along the interior surfaces of its side walls. The preferred air cleaning apparatus provides a first slot and water curtain through which air flows with the air velocity increased in the slot and then slowed down in a larger volume separation chamber. The direction of air and water flow are reversed several additional times with the air flowing through several additional water curtains. The water and air are discharged into a large precipitation chamber in which the water is collected and the air velocity is reduced very substantially before discharge through an air exhaust duct.

Abstract: A spray booth that provides an improved, more uniform circulation of air past the operator and workpiece and a more effective cleaning of the air of oversprayed particulates. A plurality of water washes are utilized in the air cleaning section of the spray booth. The spraying section includes an open-faced front user portal with a grated flooring. The cleaning section includes three water washes. The first water wash underlies the grated flooring and has a spillway that slopes downward from the front of the portal towards the rear. The second water wash is disposed at the rear of the spraying section and includes a plurality of baffle surfaces that extend across the width of the spraying section from the ceiling toward the spillway, with the bottoms of the baffle surfaces and the surface of the spillway defining a space therebetween.

Abstract: A wet pump-less spray painting booth is provided that more efficiently removes overspray paint particles from the air and uses substantially less make-up water than prior designs of wet pump-less booths. In a rear air cleaning section of the booth, blower-generated air flow sucks water from a lower reservoir up through ducts into an upper plenum where the air and water impact against a splash plate, creating a turbulent mix of air and water. Water from the upper plenum drains through tubes to an upper reservoir and overflows the upper reservoir along a sheet, the bottom edge of which is spaced a substantial distance from the lower reservoir, creating a water curtain.

Abstract: Spray particles are removed in at least a 180.degree. surround of an article traversing an arcuate path in the interior of a spray booth. The booth includes a water wash extending vertically for a height greater than the work area and a spray area and preferably extends upwardly to the area of an overhead conveyor. Air flow is maintained at a substantially constant velocity to carry overspray particles into the water wash and away from the article and a water particle eliminator eliminates water particles from the cleaned air being discharged. The preferred booth comprises a plurality of adjacent units set at angles to each other to define a polygon of at least 180.degree. with a planar water wash means being provided in each unit. A conveyor protection device may be used which discharges positively pressure air from a housing about the conveyor with the air flow in the booth pulling this blown air away from the spray areas and booth portal and into and through the water wash.

Abstract: A spray booth is provided with an air cleaning system to remove airborne particles for use in heavy production applications where large amounts of paint are sprayed and in which large quantities of airborne particles are collected without a substantial reduction in air flow through the booth as would fall below desired minimum standard of air flow through the booth. Air flows through an open front face of the spray booth and across the piece being sprayed to a first water cascade means which has vertical water covered surfaces offset in the fore and aft direction to trap paint particles and which define vertical extending slots through which the air may pass. The air is deflected downwardly from the first water means across the top surface of a water reservoir at the bottom of a spray booth at which surface further paint particles are trapped. The air then directed upwardly through a downwardly directed water spray wash which traps more airborne paint particles.

Abstract: A paint spray booth including water wash means for removing airborne paint particles from air flowing through the booth. A holding tank at the bottom of the booth collects the water from the water wash means and a pump recirculates the water from the holding tank to the water wash means near the top of the booth. A filtering tank is connected to the holding tank and is located outside the booth. A pair of filters are disposed in series in the filtering tank and filter the water as it passes from the holding tank to the pump. The filters are individually removable from the filter tank for cleaning and/or replacement so that when one filter becomes clogged, it can be removed and cleaned while the other filter continues the filtering process so that there is no interruption in use of the spray booth.

Abstract: This invention teaches an improved exhaust system to be used with a paint spray booth and having a continuously operating power exhaust fan. The exhaust system has a damper that is opened when spraying actively is taking place in the spray booth and that is closed when there is no spraying actively taking place in the spray booth. A control switch is mounted in any of several locations to determine when the spray gun is in use or is not in use. Thus, the control switch is actuated when the spray gun is hung up . . . indicating a nonuse condition of the spray system; whereupon use of the spray gun lifts the gun from the hook to indicate spraying activity. A motor drives the damper to the opened position; and a spring biases the damper to the closed position. A timer is also used to delay the closing of the damper until between twenty and possibly two hundred seconds have lapsed after spraying activity has terminated.

Abstract: A protected conveyor for a spray chamber or spray booth is provided with a pressurized housing and an air curtain means which substantially isolates the conveyor from the deleterious fluids within the spray booth and substantially isolates the articles from droppings from the conveyor. More specifically, a blower supplies air under pressure to a plenum connected to a nozzle means which discharges a thin curtain of air transversely across a slot in the housing wall and transversely across depending conveyor hangers extending downwardly through the slot. The blower also supplies air under pressure to the housing to provide air discharge out of the housing slot. The transverse air discharge combines with and redirects the air discharge through the slot as common continued air movement transversely away from the conveyed articles and toward an external air exhaust from the booth. The housing, conveyor and air curtain means are formed in an inexpensive manner.