The present disclosure is directed to mobile radiation systems and methods of curing radiation curable coating compositions to form a cured coating layer, particularly in the field of collision and cosmetic repair of body parts of vehicles such as cars and trucks.
Various curing devices and use of radiation curable coatings and devices or systems for use in collision and cosmetic repair of body parts of vehicles such as cars and trucks are known. Conventional devices and uses typically require a combination of radiation curable coatings, such as primers, a radiation source or radiator, and a power supply. For example, systems currently available from Cure-Tek® in 400 W and 1200 W systems are large, clumsy and difficult to maneuver in a congested repair shop. Typically the curing area is small in relation to these systems, and the irradiation output is typically about 100 milli-watts at a distance of about 10 inches. In this system the lamp is stationary while curing, and must be moved from place to place in order to cure relatively large surfaces such as vehicle body panels. Also, due to the round, or circular configuration of the reflector, insufficient irradiation intensity and non-uniform curing, a “light ring” defect results in some applications.
Also, while typically, an ultraviolet (UV) source such as a UV lamp can be used for curing a UV curable coating composition, such as a paint primer, applied over a substrate to form a cured coating layer; such UV radiation from the UV lamp can be harmful for operators during the use. This problem is in addition the aforementioned deficiencies of conventional irradiators, and their poor quality, inefficient and slow irradiation times that have plagued the collision and cosmetic repair of vehicles industry.
Typically, modern primers are polymeric in nature and are dried, or cured through use of a photo-initiator. UV radiation in the range of about 200-400 nm is typically used as a photo-initiator in this industry. Conventional irradiators used in this industry are not mobile, have irradiation sources that provide point or narrow radius concentration of curing irradiation, typically UVA, are clumsy to handle, and lack control and indication information that would be useful to an operator.
In the automotive repair industry, repair of cars and trucks often require painting or repainting of various surfaces, ranging from repainting of entire panels of body parts for the vehicle to repainting relatively small areas that have suffered dents, scratched, and the like. Typically, repair of vehicles includes preparing the surface to be painted or repainted, which typically includes coating the surface with a primer in the painting booth of a body shop in order to comply with OSHA and other governmental regulations. In these uses the slow and uneven curing provided by conventional irradiators are sources of problems. Specifically, because typical, slow conventional curing times, typically about 30 minutes results from use of conventional curing irradiators. These slow cure times create bottlenecks in high volume applications because the painting booth is then tied up while the primer cures and is not available to the operators for other tasks such as sanding the cured surface in preparation for actual painting.
With the novel UV mobile curing devices described herein, improved methods of curing irradiation curable coatings are made possible, particularly in the vehicle repair industry where car and truck panel surfaces and areas that have suffered nicks, scratches or other relatively small area damage require re-painting. The basics of UV curing technology are known, as shown for example on the Internet at http://www.cureuv.com/uv-lamp-curing-technology-101.html. For the purpose of the presently described devices and methods the terms WPI, intensity, dosage, wavelength, reflector, and cooling and photo initiator are intended to have the same meaning as defined in this Internet reference. With respect to the UV curing methods described herein, UV lamps used in these methods generally produce a spectrum of radiation as is known. As is also well known, industrial curing, the intended use of the described mobile irradiator and methods herein, is conducted primarily in the range of UV-C, UV-B and near UV-A, that is, from slightly below about 200 nm to slightly above about 400 nm. The peak intensity occurs at about 365 nm, with other smaller peaks at other wavelengths. The far ultraviolet lies between 200 nm and 300 nm, and is referred to as Germicidal or UV-C. The middle ultraviolet lies between 280 nm and 320 nm and is referred to as Erythmea (suntan) or UV-B. The near ultraviolet lies between 320 and 400 nm, and is commonly called Black Light (long ultraviolet) or UV-A. Therefore, needs exist for improved irradiation system for use in collision and cosmetic repair of vehicles that successfully address these known, long-felt needs.
To address the aforementioned problems and needs, described herein are embodiments of hand-held irradiators that are mobile, that deliver known, constant UV radiation and at predetermined distances from the surface to be cured to maximize the curing rate of the curable coating on a substrate, and that provide operator controls and system operating information. The present systems also provide shielding for operators to minimized exposure to UV and IR radiation while the irradiator is in on “ON”, but stand-by condition.
Also described herein are embodiments that are adapted for high volume curing of relatively large coated surfaces, such as vehicle body panels; mobile embodiments that are adapted for curing relatively small areas of a coated surface, such as found at scratches and dents on a vehicle body; and, portable, mobile embodiments that are adapted to be transported and quickly set up for use in curing a surface have an curable surface coating.
The presently described mobile systems are also adapted and configured to provide a relatively narrow band of irradiation that extends along the length of its hand-held irradiator, with the irradiator's reflector configured to provide maximum intensity of irradiation along this narrow band. With these features incorporated into embodiments of the presently described systems a coated surface of relatively large surface, such as a vehicle body part, can be cured at about the same rate of speed of spraying primer or other coating on the surface, and with the hand-held irradiator held at about the same distance away from the surface as is the sprayer for applying the primer or other coating.
With respect to other lower power, “touch-up” embodiments, provided with a lower power ballast and lamp, and with a smaller hand-held irradiator, increased flexibility in use applications and environments is made possible.
Thus, with the presently described systems, greatly improved, faster, more reliable and efficient methods of UVA curing of curable surfaces are provided.
More specifically, one embodiment of the present invention is directed to a mobile radiation system comprising:
Also, an alternate embodiment of the present invention further directed to a mobile kit for a mobile radiation system, the kit comprising:
The features and advantages of the present system and methods will be more readily understood by those of ordinary skill in the art from reading the following detailed description. It is to be appreciated that certain features of the system and methods are, for clarity, described in the context of separate embodiments, and that features of the various embodiments may be provided in various combinations in a single embodiment or in different embodiments. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in sub-combination(s). In addition, references in the singular may also include the plural (for example, “a” and “an” may refer to one, or one or more) unless the context specifically states otherwise.
The use of numerical values in the various ranges specified in this application, unless expressly indicated otherwise, are stated as approximations as though the minimum and maximum values within the stated ranges were both proceeded by the word “about.” In this manner, slight variations above and below the stated ranges can be used to achieve substantially the same results as values within the ranges. Also, the disclosure of these ranges is intended as a continuous range including every value between the minimum and maximum values.
This disclosure is directed to a mobile radiation system 10 and to methods of curing radiation curable compositions, such as paint, paint primers and the like. A preferred embodiment of the mobile radiation device comprises:
(a1) a mobile radiation device radiator (1) coupled to a control unit (2) via one or more coupling devices (3) and a power supply;
(a2) a radiator next including a radiation blocker (4) having an adaptor opening (5) for receiving said mobile radiation device (1) when said mobile radiation device is in a seated position on said radiator (4);
(a3) a mobile carrier comprising a first compartment (11) for housing said radiator and said radiation blocker, a second compartment (12) for housing said control unit, and one or more carrier motion devices or wheels (13);
wherein said adaptor opening dimensionally fits said mobile radiation device radiator to block radiation from said mobile radiation device when said mobile radiation device is in said seated position in said nest.
Referring to
Referring to
Individual controls on the control unit 2 preferably are adapted to adjust or control the UV irradiation power, duration of radiation, or a combination thereof. The irradiation power delivered to the coating to be cured is adjusted by adjusting power to the mobile radiation device, also known as the radiator, adjusting the distance between the radiator and the coating to be irradiated, the configuration of the UV reflection assembly, or a combination thereof. The control unit 2 preferably includes one or more display devices, 2a, 2b, and one or more adjustment devices such as dials 2d, 2e and 2f, as shown in
A preferred mobile radiation system is adapted to produce UV radiation having peak radiation wavelength in a range of from 250 nm to 450 nm and peak irradiation power in a range of from 0.5 W/cm2 to 10 W/cm2. Different UV sources can be used produce UV irradiations at same or different wavelengths. In one example, an arc UV source can have a peak wavelength at about 315 nm or 365 nm. In another example, an LED UV source can have a peak wavelength at about 365 nm.
The radiation blocker can comprise one or more UV blocking elements 6 that permit visible radiations 21 to exit the radiation blocker while blocking UV radiations 22 from exiting said radiation blocker, when said mobile radiation device is in the seated position, as shown in
One advantage of the system disclosed herein is that the UV blocking elements 6 can permit visible radiations 21 to exit the radiation blocker so an operator can visually confirm that the UV source is actually powered when the mobile radiation device is seated on the radiation blocker nest without being exposed to the UV irradiation.
The mobile carrier can further comprise a coupler supporting device 14 for storing and supporting said one or more coupling devices or power and/or control signal cords 3 that couple the mobile radiation device and the control unit, as shown in
The mobile carrier can further comprise at least a cooling device 16 for cooling said mobile radiation device in said seated position. The cooling device can comprise a carrier cooling fan 16, as shown in
The cooling device can comprise a cooling sensing device 17 to power on the cooling device when said mobile radiation device is in the seated position. When the mobile radiation device is moved from the seated position, the cooling sensing device 17 can automatically turn off the cooling device to conserve power.
The mobile carrier can further comprise an activity sensing device 18, as shown in
The mobile radiation device can comprise at least one cooling vent 40 on the radiation device, as shown in
The mobile radiation device can further comprise a radiation reflector 44, as shown in
The one or more carrier motion devices 13 can be selected from wheels, powered wheels, rolling wheels, tracks, rails, or a combination thereof.
The mobile radiation system can further comprise a battery power source 32 for supplying power to the mobile radiation device 1, the control unit 2, or a combination thereof.
The mobile carrier can further comprise one or more radiation supporting devices 19, as shown in
The aforementioned target can comprise a target coating layer 34, such as a wet coating layer over a coated area of a substrate 31, as shown in
Chemical curing can include the reactions between crosslinkable and crosslinking functional groups. Typical crosslinkable and crosslinking functional groups can include hydroxyl, thiol, isocyanate, thioisocyanate, acid or polyacid, acetoacetoxy, carboxyl, primary amine, secondary amine, epoxy, anhydride, ketimine, aldimine, or a workable combination thereof. Some other functional groups such as orthoester, orthocarbonate, or cyclic amide that can generate hydroxyl or amine groups once the ring structure is opened can also be suitable as crosslinkable functional groups.
It would be clear to one of ordinary skill in the art that certain crosslinking functional groups crosslink with certain crosslinkable functional groups. Examples of paired combinations of crosslinkable and crosslinking functional groups can include: (1) ketimine functional groups crosslinking with acetoacetoxy, epoxy, or anhydride functional groups; (2) isocyanate, thioisocyanate and melamine functional groups each crosslinking with hydroxyl, thiol, primary and secondary amine, ketimine, or aldimine functional groups; (3) epoxy functional groups crosslinking with carboxyl, primary and secondary amine, ketimine, or anhydride functional groups; (4) amine functional groups crosslinking with acetoacetoxy functional groups; (5) polyacid functional groups crosslinking with epoxy or isocyanate functional groups; and (6) anhydride functional groups generally crosslinking with epoxy and ketimine functional groups.
The irradiation curable functional groups can include ethylenically unsaturated double bonds, such as acrylic or methacrylic double bonds. Sources of UV irradiation for curing can include natural sunlight or artificial UV radiation sources. Examples of UV irradiation for curing can include, but not limited to, UV-A radiation, which falls within the wavelength range of from 320 nanometers (nm) to 400 nm; UV-B radiation, which is radiation having a wavelength falling in the range of from 280 nm to 320 nm; UV-C radiation, which is radiation having a wavelength falling in the range of from 100 nm to 280 nm; and UV-V radiation, which is radiation having a wavelength falling in the range of from 400 nm to 800 nm.
A coating composition having crosslinkable and crosslinking functional groups and the irradiation curable functional groups can be cured by a combination of the chemical curing and the irradiation curing. Such coating compositions can be referred to as a dual cure coating composition.
The substrate can be a vehicle or vehicle part.
This disclosure is further directed to a kit for a mobile radiation system. The kit can comprise:
(b1) a mobile radiation device;
(b2) a control unit;
(b3) one or more coupling devices;
(b4) a radiation blocker having an adaptor opening for receiving the mobile radiation device (1) in a seated position on the radiation blocker;
(b5) a mobile carrier comprising a first compartment for housing the radiation blocker, a second compartment for housing the control unit, and one or more carrier motion devices;
wherein the mobile radiation device is connectable to the control unit via the one or more coupling devices;
the adaptor opening dimensionally fits the mobile radiation device to block radiations from the mobile radiation device when the mobile radiation device is received in the seated position on the radiation blocker.
The mobile radiation device of the kit can be configured to produce radiations having peak radiation wavelength in a range of from 250 nm to 450 nm and has a peak irradiation power in a range of from 1 W to 10 W.
The radiation blocker of the kit can comprise one or more UV blocking elements 6 that are capable of permitting visible radiations 21 to exit the radiation blocker while blocking UV radiations 22 from exiting the radiation blocker, the one or more UV blocking elements are transparent, translucent, fluorescent, or a combination thereof.
The mobile carrier of the kit can further comprise at least a cooling device 16 connectable to the mobile radiation device and the control unit for cooling the mobile radiation device, and the cooling device comprises a cooling sensing device 17 connectable to the cooling device to power on the cooling device when the mobile radiation device is received in the seated position.
The mobile carrier can further comprise an activity sensing device 18 connectable to the mobile radiation device and the control unit to power off the mobile radiation device when assembled and powered, if the mobile radiation device is powered and remains in the seated position for a predetermined period of time.
With reference to
A preferred cart 52 is a Luxor brand, AVJ42C, A/V cart with locking cabinet that is commercially available.
As shown in
The housing 52 preferably contains the power supply for the device, partially shown in
Referring to
The irradiator 56 also includes a top handle 98 for use in holding the irradiator during normal operation. Handle 98 is preferably positioned on the top side of the irradiator, lengthwise and at a height sufficient for the user to hold the irradiator and for enough space or height between the top of the filters 94 and the user's gloved hand to permit free flow of air out of the irradiator and through the cooling fans or vents 94. The irradiator also includes inner lamp cartridge 100, shown in
As shown in
Referring to
To operate the system, disengage lamp stop buttons 230 and 232 are disengaged. One of the stop buttons, or emergency stop switches, is preferably located on the irradiator 230 and the other is on the operator station 232 as shown in
During the warm-up phase all capacitors are energized by high power contacts 272 as controlled by the high power relay coil 218. The high power relay coil 218 is controlled by the warm-up timer contacts 214. These contacts are controlled by the lamp ready timer 252 which is preferably set to 2 minutes and automatically switches the lamp down to stand-by mode once this time is achieved by removing the signal power for the high power relay coil 218. Also during warm-up the tri-color lamp status indicator will be amber, with both the red LED 226 and green LED 250 energized. When the lamp ready timer 252 achieves its set point, then power will be removed from the red LED 226 and the lamp status indicator will show green.
Once the lamp status indicator shows green the system is ready to use. The operator can then remove the lamp irradiator from the nest on the top of the cart. When the irradiator is removed from the nest, the nest switch 212 will energize the nest switch relay 210 which will cause the nest switch relay contact 216 to close, and which will then allow the lamp to be switched to high power. The lamp irradiator can then be used to cure the curable surface, such as a coat of automotive paint primer, by passing the irradiator in front the surface to be cured at a distance from its surface of about 6 inches using a steady and overlapping motion, preferably at about the same rate of speed and at about the same distance from the surface as would take place when spraying the primer onto the surface. Once the curing operation is complete the operator puts the lamp irradiator back in to the nest. The nest switch 212 then allows the lamp to go back to stand-by power.
To turn OFF the UV lamp 280, either one of the lamp buttons 230 or 232 is depressed. In order to re-ignite the UV lamp 280 a sufficient amount of cooling time is required to allow the mercury inside the UV Lamp 220 to re-condense.
The system preferably includes an automatic shut-off timer that functions to turn the system OFF after a predetermined time of no use and lamp hour indication. After the “lamp ready” condition is achieved and the lamp irradiator is not removed from the nest after a pre-set period, as controlled by idle shutdown timer 222, the lamp will be turned off by the idle shutdown timer contact 236. The lamp hour timer 252 indicates the remaining time, in hours, of the ideal lifespan of the UV Lamp 280, typically 500 hours. The lamp hour timer 252 counts time as long as the UV lamp start relay contact 254 is closed. Once the timer reaches zero the lamp hour timer contact is opened 242 and the lamp is turned off and cannot be reignited until the lamp hour timer 252 is reset. After the operator installs a new UV lamp 280, the lamp hour reset switch 256 is activated using a key, which will reset the lamp hour timer 252 to 500 hours, at which time the lamp can be reignited.
With reference to
The system 300 includes a case 302 having a middle cavity 304 adapted to hold a predetermined length of electrical cord, a first or front side panel 306 and a second side panel 308. Hand held irradiator 310 is shown resting in nest 312. The irradiator 310 includes a top handle 314, filter 316 and 318, which overlie fans 320 and 322, not shown, but which are preferably the same filters and fans, respectively, as described above. The hand-held irradiator also includes an emergency stop switch 324 and power cord connector 326.
The electrical control and system operating indicators are positioned on a top surface of its power supply, for advantageous use by the operator. Preferably, the power supply and these controls and indicators include irradiator cable connection 328, inlet power cable connection 330, circuit breaker 332, DC power on indicator light 334, lamp status indicator 336, lamp stop switch 338, lamp start button 340, lamp hour life indicator 342 and keyed lamp hour timer reset switch 344. These components are similar to those as described above, except that they are configured for an 1100 watt system and to fit within a hand-held carrying case.
The above-described systems are used cure irradiation curable surfaces, most preferably for curing as primers used for collision and cosmetic repair of vehicles. Use of these systems now enables a typical 30-minute cure time to be reduced to less than 1 minute and with improved quality of result, more uniform curing and increased safety to the system operator. A preferred method of irradiation curing includes the following steps. First, damage repair steps should be taken, which includes:
Preparing the surface by sanding down the scratched, dinged or other area for refinishing with 220 grit sand paper abrasive, in the same way as for most any other body repair.
Uniformly abrading the area of damage and masking it for overspray.
Providing a generous extended area for feather coat.
Wiping down the surface with high flash solvent (high flash insures no residue while removing any form of residue, dust or contamination).
Shaking the aerosol containing the UV curable coating can for 2 minutes after hearing that the mixing marble inside the aerosol can is free. (With larger repairs an option to use a HVLP spray gun version of UV curable materials is typically available).
Spray testing the aerosol insuring it is spraying correctly.
Using a uniform spray pattern apply 2 to 3 even coats of UV primer or finish, not exceeding 5 mil in thickness with most materials.
Providing about a 1-minute flash time between coats, for Cromax brand A3130S and LE3130S UVA Primer Surfacer. Follow manufacturer instructions for other coatings.
On average allow the surface to flash about 2 minutes before moving to the UV curing step for Hybrid UV Products (not needed for 100% active UV products).
Wear all proper personal protective equipment during use, including a full face shield or welder's helmet rated against UV lights, protective clothing including gloves and a long-sleeved shirt to reduce the exposure to the skin of hands, forearms and body.
Turn ON the UV light and when the UV light has been turned ON and is up to full power, begin drying most any UV curable primer, base coat or topcoat.
Begin the curing by working or moving the UV device from one end of the surface to be coated to the other end, covering the entire area that has been sprayed with the coating.
Hold the hand-held irradiator approximately 2-4 inches from the UV curable surface as the irradiator is moved from one end to the other, and at about the same rate of travel as used during the spraying of newly primed or finished areas, (if the irradiator is held at a greater distance than 4-inches, then a slower travel speed is used in order to fully cure the surface in the same number of passes as when held at 2-4 inches). Uniform left to right motion is preferably used to pass the hand-held irradiator over the surface while maintaining speed and distance consistency, that is, about 2-4 inches from surface at about 10 feet per minute (FPM) travel speed is preferred).
Preferably pass the light over the surface of the repair using the same pattern and speed used when applying the primer.
Preferably make each advancing pass at about 50% of the cure width over the area just previously passed. For example, using a 6-inch UVA lamp and a 6-inch initial pass, the second pass would overlap the first pass by about 3-inches, and so on for each subsequent pass.
Once the primer is cured, permit the surface to cool down and cure for several seconds.
Once the surface is cooled, the primer coating on the surface is cured and the area can be sanded in preparation for sealing or top coating.
Apply a base coat of paint.
Allow the base coat to dry.
Apply a clear coat.
The above specification and figures referred to are, accordingly, to be regarded in an illustrative rather than a restrictive sense. It will, however, be evident that additions, subtractions, deletions, and other modifications and changes may be made thereunto without departing from the broader spirit and scope of the inventions as set forth in the claims.
The present application is a continuation-in-part of and claims the benefit of priority of U.S. utility application Ser. No. 13/973,841, filed Aug. 22, 2013, and claims the benefit of priority of U.S. provisional patent application 61/771,168, filed Mar. 1, 2013.
Number | Date | Country | |
---|---|---|---|
61771168 | Mar 2013 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 13973841 | Aug 2013 | US |
Child | 14152891 | US |