Abstract:
A UV module of this invention has connection block (optional), connection end cap, shutter, and exhaust end cap assemblies. The connection block has doweled or tapered bayonets for facilitated installation and removal of the UV module. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 C.F.R. §1.72(b).

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of, and hereby incorporates by reference, U.S. patent application Ser. No. 12/001,080, filed Dec. 7, 2001, which, in turn, claims priority under 35 U.S.C. §119(e) to, and hereby incorporates by reference, U.S. Provisional Application No. 60/874,212, filed Dec. 11, 2006. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    This invention relates to the printing industry and, in particular, this invention relates to devices for curing ultraviolet sensitive inks printed on substrate. 
         [0004]    2. Background 
         [0005]    Ultraviolet-sensitive ink is used widely in the printing industry. One reason for its use is that ultraviolet-sensitive ink can be quickly cured by being irradiated with ultraviolet light. Such irradiation is accomplished by directing a light beam, containing high proportions of ultraviolet light, at the printed substrate. 
         [0006]    Lamps used to generate light for this purpose also generate considerable amounts of other energy in the form of heat. This heat is usually of little consequence when a printing press is operating, because the light and heat are directed toward the substrate which is in motion during the printing process. However, if the heat and light generated by the lamp is directed at a nonmoving substrate for a sufficient amount of time, the substrate is damaged, often to the point of the ignition. Additionally, other nonmoving components of the printing press may be damaged by the high amount of heat generated from the lamps. When the printing press operation must be halted, for example to Clear obstructions or replenish ink supplies, the light generated by the lamp must be prevented from impinging the substrate. One way to prevent irradiating nonmoving substrate is to power down the lamp. However, considerable time is necessary for the lamp to generate sufficient irradiation to cure the ultraviolet-sensitive ink when power is restored. Consequently, preventing irradiation from impinging nonmoving substrate when a printing press is halted has been accomplished by housing the lamp in a structure having shutters, which can be opened to allow irradiation or closed to prevent irradiation from leaving the structure. 
         [0007]    As stated above, intense heat is generated by the UV lamp during operation. These high-energy lamps require high-voltage and fairly high current, some requiring 3000 volts and 17 amps and may generate temperatures of 1000 degrees Fahrenheit during operation. Consequently, the structures housing these high-energy lamps are subjected to periods of the extremely high temperatures. These high temperatures inescapably cause the metal components of these structures to expand and warp. One consequence of this expansion and warpage is failure of these structures to properly operate. 
         [0008]    There is then a need for an ultraviolet module, which can dependably operate when subjected to the intense heat generated by high-energy ultraviolet lamps. 
       SUMMARY OF THE INVENTION 
       [0009]    This invention substantially meets the aforementioned needs of the industry by providing an ultraviolet module capable of functioning when components of the module are expanded and warped by heat generated during operation and which can be readily adjusted without extensive or undue effort or time expenditure. 
         [0010]    A cassette style shutter drive assembly has been developed, which operates efficiently when subjected to extremely high heat generated by high-energy ultraviolet lamps. One embodiment has two shutter drive assemblies, each incorporating a clutch, drive train, and other associated components to eliminate problems associated with shutter warpage, drive train component misalignment, as well as other tolerance issues. 
         [0011]    Each of a plurality of, e.g., two, shutter drive assemblies incorporates a clutch as well as a set of features designed to eliminate problems associated with shutter warpage, drive train component misalignment, and other malfunctions due to incorrect tolerances. The shutter drive train operates both shutter drive assemblies simultaneously. 
         [0012]    A shutter shaft sleeve bearing used as a component of one embodiment of this invention includes integral internal dynamic seal glands and integral external static seal glands. The two external seals are arranged with a coolant drainway therebetween, working in conjunction with a drain port integral to the connection end cap to provide a visual leak path and indicator. 
         [0013]    A ball-drive pin engages a slot in the shutter end cap to drive the shutter. Several degrees of freedom are provided by this pin and the shutter end cap slot arrangement, thereby allowing the shutter to warp and change length without inducing undesirable forces on the drive train components. The shutter arm assembly contributes thusly to reliable shutter functionality. 
         [0014]    A pair of “indexing” clutches (e.g., one clutch per shutter) has been designed to prevent drive train binding and subsequent drive motor overload. Each clutch is bi-directional, having an adjustable break-point torque to enable automatic re-engagement. The instant clutch also allows for shutter retiming (synchronization). Each worm gear may be positively secured to a shutter shaft using a special two-piece clamp collar and a drive pin, which engages the worm gear. An angled shoulder on the collar abuttingly mates to an angled rib on the shutter shaft. These two features cooperate to function as a circumferential wedge. When the clamp fasteners are tightened, the worm gear is firmly secured in place. Loosening the fasteners on both shutter drive assemblies accordingly allows the gears to be oriented as required to time or synchronize the shutters to work together properly. 
         [0015]    The worm gear is secured to the shutter shaft in a positive manner by using a two-piece clamp collar and a drive pin. The two-piece collar clamps securely to the shutter shaft. The drive pin protrudes from the collar to engage a slot in the worm gear. The collar also features an angled shoulder which mates to an angled rib integral to the shutter shaft. These two features serve as a circumferential wedge. As the fasteners securing the two-piece collar to the shutter shaft are tightened, the worm gear is wedged toward a bearing-retaining nut. The gear is then tightly clamped between the clamp collar and the nut. The combination of the two-piece clamp collar, drive pin, and wedge-induced clamping action serves to firmly secure the worm gear in place and correctly positions the worm gear relative to the worm. This arrangement allows all worm gear teeth remain fully intact and functional so that the worm gear may rotate fully in accordance to the requirements for proper clutch operation. 
         [0016]    The shutter shafts and the exhaust shutter pivot shafts function as bearing surfaces for the shutter end cap bearings as well as for O-rings and sealing surfaces for the shutter end cap bearing seals. 
         [0017]    An integral stop is built into the center of the lower end cap to prevent either of the shutters from over-traveling or contacting the UV lamp. The stop works equally well for all contemplated manual and automatic operations. 
         [0018]    A pair of sensors monitors the “open” and “closed” positions of each shutter. These sensors are activated by a magnet embedded in the shutter shaft arm and are mounted so as to minimize contact with hot module components. The sensor/magnet arrangement provides for a range of sensor sensitivity. Once the sensitivity of the sensor/magnet arrangement is adjusted as desired, sensitivity is unaffected by changes in shutter length, shutter axial position, shutter radial position, or shutter warpage. 
         [0019]    A drain hole in the connection end cap assembly may be ported outside the instant module, thereby visually indicating the existence of an internal leak. The drain hole may also direct leaking coolant away from electrical components to reduce the likelihood of detrimental high-energy short circuits. 
         [0020]    The water poppet valve may have a double-seal arrangement. Accordingly, the instant water poppet valve may be essentially drip-free during module installation, removal, and post-removal. This high-flow valve fits into a restricted amount of space and functions in conjunction with a rotating shutter shaft and its integral coolant passageway. 
         [0021]    Shutter end cap material is matched to the shutter extrusion material to minimize galvanic and corrosive effects. The shutter end cap includes a special coolant passageway, which doubles as a reservoir and cooperates with other features to cool the stem of the UV lamp, as well as other components. 
         [0022]    The bearing/seal arrangement in the shutter end caps allows for nominal flexing, thermal expansion/contraction, warpage, and dimensional variations of the shutter assembly without sacrificing fluid-tight integrity or inducing adverse forces on seals and shutter drive train components. The instant bearing features a narrow, centrally located load-bearing surface that is sealed on either side by a pair of integral seal glands fitted with O-rings. The O-rings help to distribute the bearing loads and the outer seal also serves as a wiper. The bearing arrangement also provides for important freedom of motion for the shutter assembly relative to these shutter shafts. The bearing further acts as a heat sink and a heat transfer element further cooling the stem of the UV lamp and other components. 
         [0023]    In one embodiment, the lamp connector of this invention is a two-piece assembly, thereby allowing easier and more reliable assembly of the high-voltage socket and lead wire. Additional insulation may be present around the high-voltage wire entryway and around the socket opening. The increased insulation results in a longer and a less direct electrical leak path to thereby reduce the chance of a high-energy short circuit. 
         [0024]    Both lamp connector assemblies may be spring-loaded against the lamp. This spring-loading encourages higher and more consistent electrical conductivity, maintains full pin-socket engagement during aggressive module installations, allows for more relaxed dimensional tolerances for manufacturing the UV bulb, and minimizes high-energy short circuits. 
         [0025]    Special non-conductive, screw-ferrules may be used as a mechanical backup to thereby secure the high voltage pin and socket connectors into the electrical connection block. The ferrules also allow for easier pin and socket servicing. 
         [0026]    Coolant plugs with integral sacrificial zinc anodes may be installed directly in the coolant flow path inside the module to prevent corrosion in the coolant passage ways. The anodes may be shaped to reduce flow restrictions. 
         [0027]    The shutter end caps may have a relieved reflector mounting surface. This feature provides better UV protection for the ring located in the shutter body/shutter end cap interface and eliminates the need for custom-fit reflector strips. 
         [0028]    The reflectors may be removed and installed without removing the shutter end caps and without breaking the fluid-tight integrity of the shutter assembly. Only the retaining strip needs to be removed to exchange a reflector. 
         [0029]    The design of the instant module produces a full length, uninterrupted, properly shaped reflector supporting surface. This design further provides for quicker reflector replacement and allows the use of convenient pre-cut reflectors. 
         [0030]    In one embodiment, the original female V-shaped reflector retainer profile has been modified to include a shallow U-shaped channel. This helps to prevent shutter-to-shutter binding when the shutters are closed. The U-shaped channel does not reduce the effectiveness of how well the closed shutters block light. 
         [0031]    The coolant cross over feature may be incorporated into the upper module of this invention to facilitate easier and less expensive manufacturing and assembly. The cross over cavity doubles as a substantial reservoir to provide better component cooling. 
         [0032]    A slide-out mount for the electrical connection assembly is located in the connection block and may be easily removed to provide better and quicker service. Special three-dimensional locating features provide the precise alignment required for optimum module performance. 
         [0033]    The dove-tailed edge design of the shutter drive train access doors allows the doors to be easily removed with a minimum of module disassembly. 
         [0034]    The stub bayonet shafts act as precision two-dimensional locating dowel to provide optimum functionality to the poppet valves and electrical connections. 
         [0035]    The latch rod has locating features at the latch-end and provides accurate axial positioning of the poppet valve components and the electrical connections. 
         [0036]    The spring-loaded latch provides precise axial alignment of the instant module to the connection block of this invention. When combined with the stub bayonets and the latch rod left, a precise three-dimensional module-to-module connection block docking is easily achieved to provide for optimum module performance. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0037]      FIG. 1  is a top isometric view of one embodiment of the UV module of this invention. 
           [0038]      FIG. 2  is a bottom view of the UV module of  FIG. 1 . 
           [0039]      FIG. 3  is a top, isometric view of the connection block of this invention. 
           [0040]      FIG. 4  is a perspective view of the module of  FIG. 1  docked to the connection block of  FIG. 3 . 
           [0041]      FIG. 5  is a sectional view depicting portions of the instant shutter shaft seal arrangement and bearing arrangement. 
           [0042]      FIG. 6  is an oblique sectional view of the UV module of  FIG. 1  with the shutters in an open position. 
           [0043]      FIG. 7  is an oblique sectional view of the UV module of  FIG. 1  with the shutters in a closed position. 
           [0044]      FIG. 8  is a perspective view of one embodiment of the instant shutter shaft assembly. 
           [0045]      FIG. 9  is a perspective view of the shutter shaft assembly of  FIG. 8  and a shutter end cap of this invention, shown disengaged. 
           [0046]      FIG. 10  is a perspective view of one embodiment of the shutter drive train of this invention. 
           [0047]      FIG. 11  is a partial sectional view of the shutter drive pin/slot, depicting freedoms of motion thereof. 
           [0048]      FIG. 12  is a perspective view of one embodiment of the instant clutch, having the shutter arm thereof in phantom view. 
           [0049]      FIG. 13  is an oblique sectional view showing the instant shutters “out of time” (unsynchronized). 
           [0050]      FIG. 14  is a perspective view of the lower end cap showing an integral stop of one embodiment of the module of this invention. 
           [0051]      FIG. 15  is a perspective view depicting shutter position sensors of this invention as mounted in the instant connection end cap assembly. 
           [0052]      FIG. 16  is a sectional view of one embodiment of the poppet valve of this invention, prior to docking. 
           [0053]      FIG. 17  is a sectional view of the poppet valve of  FIG. 16  during mid-docking. 
           [0054]      FIG. 18  is a sectional view of a poppet valve of  FIG. 16  fully docked. 
           [0055]      FIG. 19  is a sectional view of the connection end of the shutter end cap bearing/seal arrangement of this invention. 
           [0056]      FIG. 20  is a sectional view of the exhaust end of one embodiment of the shutter end cap bearing/seal arrangement of this invention. 
           [0057]      FIG. 21  is an isometric view of one embodiment of the lamp connector assembly of this invention. 
           [0058]      FIG. 22  is a sectional view of the lamp connector assembly of  FIG. 21 . 
           [0059]      FIG. 23  is an isometric view of one embodiment of the ferrules and high-voltage pin connector of this connection. 
           [0060]      FIG. 24  is a sectional view of the ferrules and high-voltage pin assembly of  FIG. 23 . 
           [0061]      FIG. 25  is a perspective view of one embodiment of the coolant plugs with integral sacrificial anodes of this invention. 
           [0062]      FIG. 26  is a sectional view of the coolant plugs with integral sacrificial anodes of  FIG. 25 . 
           [0063]      FIG. 27  is a perspective view of one embodiment of the shutter end cap of this invention showing a relieved reflector mounting surface. 
           [0064]      FIG. 28  is a perspective view of the shutter end cap of  FIG. 27  installed in the module of  FIG. 1 . 
           [0065]      FIG. 29  is a perspective view of one embodiment of the cross-over location callout of this invention. 
           [0066]      FIG. 30  is a perspective view of one embodiment of the upper module cover of this invention with cross-over details. 
           [0067]      FIG. 31  is a perspective view of one embodiment of the UV module of this invention showing slide-out mount detail. 
           [0068]      FIG. 32  is a perspective view of one embodiment of the slide-out mount of this invention shown removed from one embodiment of the connection block of this invention. 
           [0069]      FIG. 33  is a perspective view of the slide-out mount of  FIG. 31 . 
           [0070]      FIG. 34  is a perspective view of one embodiment of the UV module of this invention, with an access door location. 
           [0071]      FIG. 35  is a perspective view of the UV module embodiment of  FIG. 34 , the access door thereof depicted as positioned for removal. 
           [0072]      FIG. 36  is a perspective view of one embodiment of an access door of this invention. 
           [0073]      FIG. 37  is a sectional view of one embodiment of the connection cap assembly with the access door of this invention removed. 
           [0074]      FIG. 38  is a perspective view of one embodiment of the stub bayonet of this invention. 
           [0075]      FIG. 39  is a sectional view of one embodiment of a three-axis module docking/locating feature of this invention. 
           [0076]      FIG. 40  is a perspective view of one embodiment of a latch/latch-rod assembly of this invention. 
           [0077]      FIG. 41  is a perspective view of a latch side of one embodiment of the connection end cap assembly of this invention. 
           [0078]      FIG. 42  is a sectional view of one embodiment of a spring-loaded lamp connector of this invention, biased against a lamp. 
           [0079]      FIG. 43  is a sectional view of one embodiment of a high voltage pin/socket arrangement of this invention. 
           [0080]      FIG. 44  is a side view of the UV module of this invention depicting another embodiment of the positive and negative retaining strips of this invention. 
           [0081]      FIG. 45  is a sectional view along line A-A of  FIG. 44 . 
           [0082]      FIG. 46  is a sectional view along line B-B of  FIG. 44 . 
           [0083]      FIG. 47  is a cross-section of the clutch arm of this invention depicting the ball spring plungers engaged to shutter shaft grooves. 
           [0084]      FIG. 48  is a cross-section of the clutch arm of this invention depicting the ball spring plungers disengaged to the shutter shaft grooves. 
       
    
    
       [0085]    It is understood that the above-described figures are only illustrative of the present invention and are not contemplated to limit the scope thereof. 
       DETAILED DESCRIPTION 
       [0086]    Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used to practice the invention, suitable methods and materials are described below. 
         [0087]    Any references to such relative terms as front and back, right and left, top and bottom, upper and lower, horizontal and vertical, or the like, are intended for convenience of description and are not intended to limit the present invention or its components to any one positional or spatial orientation. 
         [0088]    Each of the additional features and methods disclosed herein may be utilized separately or in conjunction with other features and methods to provide improved devices of this invention and methods for making and using the same. Representative examples of the teachings of the present invention, which examples utilize many of these additional features and methods in conjunction, will now be described in detail with reference to the drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the invention. Therefore, combinations of features and methods disclosed in the following detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe representative and preferred embodiments of the invention. 
         [0089]    One embodiment of the ultraviolet (UV) module of this invention is shown in  FIGS. 1 and 2 , and particularly in  FIG. 4 , at  100  and includes an optional connection block assembly  102 , a connection end cap assembly  104 , a shutter assembly  106 , and an exhaust end cap assembly  108 . 
         [0090]    Referring now to  FIGS. 3 ,  31 ,  32 , and  33 , the connection block assembly  102  has a connection block  120 , a slide-out mount  122 , an electrical (or socket) connection subassembly  124 , a poppet valve connection block  126 , and stub bayonets  130 ,  132 . 
         [0091]    As best seen in  FIG. 32 , the connection block  120  defines a stepped opening  140 , with horizontal surfaces  142 ,  144  facing vertical surfaces  146 ,  148  (not shown) and a lower horizontal surface  150 . Locating structures such as extensions  152 ,  154  from the horizontal surfaces  142 ,  144  and extensions  156 ,  158  (not shown) from the vertical surfaces  146 ,  148  may be present. 
         [0092]    Referring to  FIGS. 3 and 31 , an optional attachment block  160  is depicted. The attachment block  160 , in the embodiment shown, has fluid attachment features (e.g., fittings)  162 ,  164  and an electrical attachment fixture  166 . One of the fluid attachment fixtures  162 ,  164  connects to a source of ingressing fluids to cool the instant UV module during use and the other of the fluid attachment fixtures  162 ,  164  serves as a conduit for egressing coolant fluids therefrom. When attached to the connection block assembly  102 , the attachment block  160  provides for electrical and fluid supply to the UV module of this invention. While shown oriented generally horizontally to the instant UV module, a person of ordinary skill in the art will readily recognize that the coolant and electrical attachment fittings  162 ,  164 ,  166  may be vertically oriented as well, due to space constraints and the like. Moreover, a person of ordinary skill in the art will readily recognize that fluids and electricity may be supplied to the UV module of this invention by other means as well. A person of ordinary skill in the art would further recognize that UV modules without a system or assembly for circulating coolant are also within the scope of this invention, for example, if sources of UV radiation are used which do not generate appreciable amounts of heat. One example of such a UV source is an LED emitter. 
         [0093]    As seen in  FIG. 33 , the slide-out mount  122  includes an upper member  172  and unitary (or otherwise integral) extensions  174 ,  176  extending from the upper member  172 . An electrical connection assembly mounting face  178  is defined by the extensions  174 ,  176  and a lower portion of the upper member  172 . Locating features are functionally defined as slots  180 ,  182 , each defined in a lower portion of the upper member  172  adjacent each extension  174 ,  176 . Further locating features include slots  184 ,  186  (slot  186  not shown) defined in outboard surfaces of the extensions  174 ,  176 . Threaded apertures  188 ,  190 ,  192 ,  194  are present in the extensions  174 ,  176 . 
         [0094]    The instant slide-out mount for electrical connection assembly, located in the connection block docking with the module, may be conveniently attached to and removed from the attachment block  160  to facilitate assembly and disassembly. Due to the facilitated attachment and removal, the slide-out mount also significantly reduces servicing time. Locating features in this slide-out mount provide the precise three-dimensional alignment required for optimum module-to-connection block interface performance ( FIGS. 31 ,  32 ,  33 ). 
         [0095]    As viewed in  FIGS. 3 ,  15 ,  33   39 ,  42 , and  43 , and especially in  FIGS. 32 and 43 , the socket connection block subassembly  124  has a housing  200 , which encloses sockets  202 ,  204  and ferrules  206 ,  208 . In one embodiment, the ferrules  206 ,  208  are made from a non-conductive material and are threaded into openings in the connection block housing  200 , thereby securing the sockets  202 ,  204  within the housing  200 . The sockets  202 ,  204  are accessed by means of openings  210 ,  212  in the housing  200 . The socket connection block  124  is secured to the slide-out mount  122  by threading fasteners through apertures  214 ,  216 ,  218 ,  220  present in the housing  200  and into the apertures  188 ,  190 ,  192 ,  194  (present in the slide-out mount extensions  174 ,  176 ). While two sockets  202 ,  204  are depicted and described, a person of ordinary skill in the art would readily recognize that more sockets may be present, e.g., to accommodate other voltages. As seen in  FIG. 43 , at least one, e.g., a pair of elastomeric elements, such as O-rings  228 . are optionally disposed between the electrical connection block subassembly  124  and the slide out mount  122  when the electrical connection block subassembly  124  is attached to the slide out block  122  using fasteners, such as shoulder screws  230 . While O-rings  228  are depicted as being secured by each of the shoulder screws  230 , this may not be the case in other embodiments of this invention. For example, one or more of the  0   228 -rings may be secured in a pair of diagonal or opposing corners. The elasticity of the O-rings enables the connection block subassembly  124  to move slightly during docking. Consequently, the elastomeric characteristics of the O-rings, when present, maintain the electrical connection subassembly  124 , hence the connection block assembly  102 , in a position such that the sockets are centered or positioned to receive the pins when connecting the connection block assembly  102  to the remainder of the instant UV module. as more fully described below. Upon engagement of the connection block assembly to the remainder of the module, the elasticity of the O-rings  228  ensures that the electrical connection pins can slide into their respective sockets without misalignment due to the ability of the electrical connection subassembly  124  to displace within the limits of the elasticity of the O-rings  228 . Accordingly, initial misalignments of the sockets and pins are corrected during connection or docking or whenever the connection block assembly  102  is not completely engaged to the remainder of the UV module. In UV modules of the prior art, the absence of the elastically enabled or self-correcting alignment sometimes resulted in misalignment of pins and sockets when connecting the connection block assembly to the remainder of the UV module. Consequently, the pins were not completely seated in the sockets and the electrical connections were incomplete and arcing sometimes occurred between the misaligned sockets and pins. Additionally, the sockets and/or pins were bent or damaged due to the misalignment. In other embodiments of the prior art, the connection assembly was spring mounted, thereby resulting in an attenuated ability to maintain the desired centered position. Consequently, the pins were sometimes ejected from their mounts when engaging the sockets. Ejection of pins often caused mechanical damage to the pins or sockets, arcing, and occasionally fires from the arcing. The foregoing self-centering feature of the instant electrical connection subassembly functions in conjunction with the precision dowel feature of the stub bayonets (described below) of the UV module of this invention to ensure that connecting elements of the connection block assembly  104  are properly aligned with corresponding elements of the remainder of the instant UV module. 
         [0096]    Referring to  FIGS. 32 ,  33  the rear surface of the electrical connection subassembly  124  contacts the electrical connection assembly mounting face  178  of the slide-out mount  122 . The modular slide-out mount  122  is attached to the connection block  120  by disposing the slide-out mount  122  into the opening  140 , such that extensions  152 ,  154  are disposed in slots  180 ,  182  and such that extensions  156 ,  158  are located in slots  184 ,  186 . When the slide-out mount  122  is disposed in the opening  140  as described, apertures  188 ,  190  in the slide-out mount  122  are aligned with threaded apertures  224 ,  226  (defined from surfaces  142 ,  144  of the connection block  120 ). Accordingly, the slide out mount  122  can be secured in place by threading fasteners through the foregoing aligned apertures. While the connection block of this invention is depicted as having electrical connection sockets, it should be appreciated that electrical pins could be present in place of the sockets, so that electrical connection pins shown below as present in the pin connector assembly could be replaced by sockets. 
         [0097]    As seen in  FIG. 32 , the poppet valve connection block  126  includes high flow water poppet valves  240 ,  242 , which are housed in the connection block  120 . Referring now to  FIGS. 16 ,  17 , and  18 , each of the poppet valves  240 ,  242  (poppet valve  240  shown) has a water stem  243  axially retained within a water sleeve  244 . A water stem seal  245  is disposed about an inner surface of the water sleeve  244 . An exterior seal  246  is disposed about a central portion of the water sleeve  206 . A spring (not shown), also present within the water sleeve  206 , urges the water sleeve  244  to the right (from the perspective of  FIG. 12 ). 
         [0098]    The water poppet valve of this invention has a double seal arrangement provided by seals  245 ,  246  ( FIGS. 3 ,  5 ,  16 - 18 ). The double seal provides a virtually drip-free connection during module installation, as well as a drip-free connection when the instant module is undocked. Stated otherwise, all components are closed during initial module engagement to the connection block and again closed prior to final disengagement from the connection block. Accordingly, very little, or no, fluid escapes the valve when the instant module is being installed or removed. The instant poppet valve, in contrast to other known poppet valves, functions in conjunction with a rotating shutter shaft, the rotating shutter shaft doubling as a coolant passage way. 
         [0099]      FIGS. 3 ,  32 , and  38  depict the present stub bayonets  130 ,  132 , which may unitarily (or otherwise integrally) have six cylindrical portions. A first cylindrical portion  250  adjoins a second cylindrical portion  252 , the second cylindrical portion  252  with a greater diameter. A third cylindrical portion  254  has a smaller diameter than either of flanking portions  252 ,  256 . The increased diameter of the cylindrical portion  256  produces a tapered (or stepped) “precision dowel surface,” as more fully explained below. A diameter of the stub bayonets  130 ,  132  continues to decrease (taper) at cylindrical portions  258 ,  260 . A latch mating surface  262  is defined by facing surfaces  264 ,  266  (surface  266  not shown) and  268 . The function of the latch mating surface  262  is more fully described below. The cylindrical portion  260  is secured within the connection block  120 , as depicted in  FIG. 3 . 
         [0100]    The two stub bayonet shafts guide, support and dock the connection block assembly as it is attached to, and functions with, the remainder of the instant UV module. Due to the close concentric tolerances required for optimum functionality of the water poppet valves and the electrical connections, a short section of the stub bayonets is slightly increased in diameter to act as a pair of precision locating dowel pins. This feature accurately docks the module to the connection block. The two-dimensional (up/down and side-to-side) mating precision resulting from this dowel effect enables increased flow through the water poppet valves and eliminates the pin and socket ejection problems associated with misalignment. When the precision dowel locating effect is combined with the axial (in/out) positional control gained from the instant latch rod and the instant spring-loaded docking latch (as more fully explained below), optimum functionality of the poppet valves and the electrical connections are achieved ( FIGS. 3 ,  38 - 41 ). 
         [0101]    Referring to  FIGS. 1 ,  2 ,  4 ,  5 ,  10  and  16 , the connection end cap assembly  104  is enclosed in a housing  280  and includes a shutter drive train assembly  282 , a connection end cap valve assembly  283 , an end cap electrical assembly  284 , and an end cap latch assembly  286 . 
         [0102]    As best viewed in  FIG. 10 , the shutter drive train (assembly)  282  includes a connection end cap  290  (as seen in  FIG. 14 ), a drive gear motor  292 , first and second spur gears  294 ,  296 , a worm shaft  298 , and left and right shutter drive subassemblies  300 ,  302 . However, in some embodiments, the instant drive train may be considered to include connection shutter end caps  570 ,  172  (discussed below). The drive gear motor  292  rotates the spur gear  294  which, in turn, rotates the spur gear  296 . The spur gear  296  is attached to, and rotates, the worm shaft  298 . The worm shaft  298  has respective left and right hand segments  304 ,  306 , which, in turn, rotate the shutter drive subassemblies  300 ,  302 , as more fully explained below. However, a person of ordinary skill in the art will recognize that the shutter shafts  332  may be directly rotated by the motor  292  or that other combinations of gears to comprise the instant drive train are within the scope of this invention. As seen in  FIG. 15 , also included in each of the left and right shutter drive subassemblies  300 ,  302  are sensor mounts  308 ,  309  and a pair of sensors  310 . 
         [0103]    Within the instant connection end cap assembly is a geared drive motor. Via a set of spur gears, this geared drive motor turns a worm shaft having left-hand and right-hand thread segments. Each of these worm shaft segments turns a worm gear secured to a shutter shaft. The gear motor spins the worm to open or close both shutters simultaneously. 
         [0104]    As seen in  FIGS. 8 ,  9 ,  10 ,  11 ,  12 ,  40 , and  41 , respective left and right shutter drive subassemblies  300 ,  302  are rotatably attached to the shutter shafts  332  and have clutch pin drive assemblies  316 ,  318 , and worm gears  324 ,  326 , as well as substantially identical (or similar) shutter shafts  332 , collars  334 , (hex) nuts  336 , ball bearings  338 , and worm gear drive pins  340 . The left and right clutch pin drive assemblies  316  are rotatably attached to each end of the shutter shafts  332  and  318  respectively include shutter arms  350 ,  352  and shutter arm extensions  354 ,  356 , the other components described below being substantially identical or similar. Referring now to  FIGS. 8 ,  9 ,  11 ,  12 ,  40 , and  41 , a ball headed drive pin  358  axially extends from each of the shutter arm extensions  354 ,  356 . Each of the ball headed drive pins  358  has a shank  360  with a longitudinal axis  361  and terminating in a head  362 . A cross sectional dimension, such as a diameter  364  of the head  362  is greater than a cross sectional dimension such as a diameter  366  of the shank  360 . 
         [0105]    A sensor magnet  372  is housed in each of the shutter arms  352 ,  354  generally opposite the shutter arm extensions  354 ,  356 . At least one or a plurality of, e.g., four, adjustable ball spring plungers  374  are disposed in each of the shutter arms  350 ,  352 . A plurality, e.g., pair, of shutter position sensors  376 ,  378  are also attached to each of the shutter arms  350 ,  352 , the shutter position sensor  376  attached so as to be aligned with a sensor magnet  372 , thereby detecting when the shutters are in an open or closed position. The shutter position sensor  378  is attached approximately radially midway between the shutter position sensor  376  and one of the shutter arm extensions  354 ,  356 , to thereby detect when the shutters are in a closed position. The two pairs of sensors (one pair for each shutter) monitor the open and closed position of each shutter. The sensors may be reed switches activated by a magnetic field and are mounted so as to minimize contact with module components directly exposed to high temperatures found in the instant UV module. The magnets are stronger than those previously used to ensure sensor activation. A variety of magnet lengths (thus, a variety of magnetic field strengths) may be used to finely adjust shutter sensor sensitivity. The magnets are present in the shutter shaft arms which are, in turn, mounted on the shutter shafts. Accordingly, the sensitivity of the shutter position sensors is unaffected by shutter warpage, changes in shutter length, or changes in the axial positioning of the shutter assemblies relative to the module body of this invention. The sensors themselves may be also micro-positioned within their mounting brackets to more finely adjust sensor sensitivity ( FIGS. 8 ,  10 ,  11 ). 
         [0106]    Referring more particularly to  FIGS. 47 and 48 , each of the ball spring plungers  374  includes a slotted cap  380 , which closes a threaded housing  382 . A spring  384  is disposed within the housing  382  and a ball  386  partially protrudes from the housing  382 , the spring  384  biasing the ball  386  away from the slotted cap  380 . 
         [0107]    As seen in  FIGS. 11 and 12 , each of the shutter shafts  332  has at least one or a plurality of, e.g., six, axial bores  390  and an angled rib  392  is circumferentially and integrally formed from an exterior surface thereof. A plurality of axially aligned grooves (slots)  394  are formed on the exterior of the shutter shafts  332  so as to coincide with the position of the shutter arms  350 ,  352 . The shutter shaft of this invention has been extended to extend through the connection block and the associated seal arrangement has been designed to greatly reduce the chance of a coolant leak. If a leak were to occur, a tale-tale weep hole ported to the atmosphere, not only indicates the existence of a leak, but directs any leaking coolant away from the internal spaces of the connection block and module and, in particular, any coolant leakage is directed away from electrical connections and components, thereby minimizing chances of any coolant-induced electrical shortages and any damages to the instant module therefrom. 
         [0108]    A pair of “indexing” clutches (one per shutter) prevents drive train binding and subsequent drive overload ( FIGS. 8-12 ,  47 - 48 ). Within the clutch of this invention, a plurality of ball spring plungers are mounted within the shutter shaft arm and may be adjusted as required to produce the desired “breakpoint” torque, the amount of torque required to disengage the clutch as seen in  FIG. 47  and during normal operation with each shutter clutch engaged, the spring plunger balls  386  are forced into the grooves  394  formed in the shutter shaft  332 , thereby effectively “locking” the shutters to the drive train. The optimum “breakpoint” allows the clutch to disengage before the drive motor draws sufficient heat-producing current to be damaged, yet still operates the shutters during normal operation. As shown in  FIG. 48 , when disengaged, the balls  386  are no longer seated in the grooves  394  of the shutter shaft  332 . When properly adjusted, the present clutch in the “disengaged” mode allows the shutter drive train to continue operating in a powered-up condition for an unlimited amount of time without damaging drive train components. While under power and disengaged, the clutch can “free wheel” in a manner somewhat similar to a spring-loaded pawl and ratchet arrangement. The clutch will always automatically reengage by virtue of the “indexing” configuration integral to the shutter shaft, shutter shaft arms, and spring plungers. Stated otherwise, regardless of the position of the shutters, a disengaged clutch of this invention will always attempt to reengage. The clutch arrangement of this invention also allows the shutters to be individually repositioned by hand. Suitable ball spring plungers are available in several ranges of spring force values. These devices may have threaded bodies allowing them to be threaded into or out of the shutter shaft arm to respectively increase or decrease the torque required to reach the “breakpoint” of the clutch. The combination of the spring forces and the extent to which the threaded bodies are threaded into the clutch allows the clutch “breakpoint” to be thus readily adjustable. Due to the action of the springs, a disengaged clutch will continually attempt to reengage and will reengage automatically as soon as the applied torque in the shutter drive train system falls below the “breakpoint” torque, or as soon as the drive motor is deenergized. When a shutter is repositioned by hand, the clutch will reengage as soon as the shutter is released. The design of the clutch components is such that the clutch is bidirectional and will disengage at approximately the same “breakpoint” torque value regardless of whether the shutters are being opened or closed. The clutch operates silently when fully engaged. When operating under power in the “disengaged” mode, the clutch admits a series of subdued clicking sounds to thereby alert personnel that the clutch is disengaged and is attempting to reengage. 
         [0109]    The instant clutch also facilitates shutter synchronization. During module assembly the two shutters may be moved to their fully open positions and synchronized to mate the positive and negative reflector retaining strips. In any condition in which either or both of the shutter clutches undergo disengagement, loss of shutter timing may occur. To re-synchronize the shutters, the condition causing the clutches to disengage must often be first corrected. The shutters may then automatically reacquire the correct shutter synchronization when they are moved, either manually or via the drive motor to their fully open positions. In this situation, the module body extrusion acts as a hard stop for both shutters. When both shutters have been moved to their fully opened positions (and the drive motor, if in use, has been deenergized), both shutter clutches will automatically reengage and the shutters will again be properly timed and engaged to their respective shutter shafts ( FIGS. 6 ,  7 ,  13 ). 
         [0110]    As shown in  FIGS. 8 ,  9 , and  11 , the worm gears  324 ,  326  are secured to the shutter shafts  332  using the two piece clamp collar  334  and the drive pin  340 . Individual pieces ( 396 ,  400 ) of the clamp collar  334  clamp securely to the shutter shaft  332  and the drive pin  340  protrudes from the collar  334  to engage a slot (not shown) in each of the worm gears  324 ,  326 . When thusly secured, an angled shoulder  400  of the collar  334  abuts the angled rib  392  of the shutter shaft  332 . As fasteners  402  secure the two-piece collar  334  to the shutter shaft  332 , one of the worm gears  324 ,  326  is wedged toward the bearing-retaining nut  336 . Each of the worm gears  324 ,  326  is then tightly clamped in place between the clamp collar  334  and the hex nut  336  and is positioned to fully mesh with the left and right hand segments  304 ,  306  of the worm shaft  298 . 
         [0111]    As best seen in  FIG. 15 , the sensor mounts  308  are mounted to the connection end cap  290  secure shutter position sensors  310  in place. 
         [0112]    Referring to  FIGS. 14 and 15 , a lower end cap  406  includes an optionally integral (or unitary) hard integral stop  408  in one embodiment of this invention. The integral stop is positioned at the center of the lower end cap cover to prevent either of the shutters from over traveling and contacting the UV lamp. In the event of clutch disengagement, the shutter may be forced past the normal “shutter closed” position. In this event, the shutter shaft arm will contact the integral stop before any portion of the shutter assembly can move sufficiently to contact the lamp. Thus, this integral stop prevents UV lamp contact whether the shutters are overdriven via the drive motor or by manual manipulation and will prevent lamp-to-shutter contact, regardless of the axial position of the shutter relative to the module body ( FIGS. 13-15 ). 
         [0113]    As can be seen in  FIGS. 5 ,  16 ,  17 , and  18 , a second bearing  420  may be used in conjunction with a ball bearing  422  to support the shutter shafts  332 . In one embodiment, the second bearing  420  is a bronze, flanged, sleeve bushing. However, other suitable materials may be used for other embodiments. The bearing  420  may include integral internal dynamic seal glands  430 ,  432  and integral external static seal glands  434 ,  436 . These glands may be outfitted to accommodate seals, such as O-rings  440 ,  442 ,  446 ,  448  to provide fluid-tight integrity. The two external seals  446 ,  448  have a coolant drainway  452  therebetween. The coolant drainway  452  drains to a drain port  454 , which is integral to the connection end cap  290 , to provide a path for coolant leakage. For each of the two shutter drive assemblies, the second bearing (e.g., bronze, flanged, sleeve bushing type) is used in conjunction with a single ball bearing to provide full and solid support to the shutter shaft. The sleeve bearing may include integral internal dynamic seal glands and integral external static seal glands. These glands accommodate seals, e.g., O-rings, to provide a high degree of fluid-tight integrity. The two external seals are arranged with a coolant drainway therebetween and function in conjunction with a drain port integral to the connection end cap to provide a telltale leak path in the event of a failed primary static bearing seal. 
         [0114]    Referring to  FIGS. 16 ,  17 , and  18 , one embodiment of the connection end cap valve assembly of this invention  283  has a striker plate  456 , a valve disc  457 , a sleeve  458  with a plurality of outboard slots  459 , and a compression (coil) spring  460  (spring  460  not shown). The striker plate  456  accommodates internal O-rings  461 ,  462  about a fluid passageway  463  and an inboard O-ring  464  to seal the junction between the connection end cap valve assembly  283  and the bearing  596  (more fully described below). An open volume  465  is defined in an inboard portion of the striker plate  456  and is also bounded by the sleeve  458  and the bearing  596 . The spring  460  is disposed in the sleeve  458  and biases the valve disc  457  toward the left (as viewed from the perspective of  FIG. 16 ) such that the valve disc  457  is in a fluid tight engagement with the O-ring  462 , thereby preventing fluid egress from the valve assembly  283 .  FIG. 16  depicts what may be considered as a first stage of docking the connection block assembly  102  to the connection end cap assembly  104 , wherein the connection block poppet valve  240  and the connection end cap valve assembly  283  are both closed to fluid egress. As seen in  FIG. 17 , the opening  463  of the striker plate snugly accommodates a positive end  466  of the water sleeve  244 , such that the O-rings  461 ,  462  sealingly contact said positive end  466 . As the cooperation between the connection block poppet valve  240  and the connection end cap valve assembly  283  progresses toward the disposition depicted in  FIG. 18 , the positive end  466  of the water sleeve  244  abuts and displaces the valve disc  457  (to the right as viewed from the perspective of  FIGS. 17 and 18 ), thereby compressing the spring  460 . As viewed in  FIG. 18 , the valve disc  457  is fully displaced, no longer in a sealing position, thereby allowing fluid to flow through the poppet about  240  and into the valve assembly  283 . Coolant thusly flows around the valve this  457 , though the slots  459  and sleeve  458  in two the shutter shaft  332 . A person of ordinary skill in the art will readily recognize that when undocking the connection block assembly  102  from the connection end cap assembly  104 , the connection block poppet valve  240  and the connection end cap valve assembly  283  are sealed to prevent fluid egress by events essentially the reverse of the foregoing description. 
         [0115]    As may be viewed in  FIGS. 15 ,  21 ,  22 ,  23 ,  24  and  42 , the end cap electrical assembly  284  includes a UV lamp  468 , a lamp connector  470 , a pin connector assembly  472 , and a board  474 . The UV lamp  468  fits into, and is secured in place by, the lamp connector  470 . Referring to  FIGS. 21 and 22 , the lamp connector  470 , in turn, has a high-voltage cable  480 , a two-piece housing  482 , a fastener mechanism  484 , an insulating membrane  486 , and socket  488 . The two-piece housing  482  depicted in this embodiment may include two housing components  492 ,  494 , which house the high voltage socket  488 , the insulating membrane  486  and a ring terminal  496 . As best shown in  FIG. 22 , a plurality of connectors, e.g., two, sex bolts  498  attach and secure the high voltage cable  480  to the ring terminal  496 . As seen in  FIG. 15 , the conductors within the high voltage cable  480  (not shown) may be connected directly to the pin connector  472 , or connected to the pin connector  472  via the connector board  474 . When the lamp connector  470  is secured in place, a spring  502  (as best shown in  FIG. 42 ) biases the lamp connector  470  toward the lamp  468 . 
         [0116]    As best viewed in  FIGS. 15 ,  23 ,  24 , and  42 , the pin connector assembly  472 , in the embodiment shown, includes an electrical connection block  510 , ferrules  512 ,  514 , and high voltage connection pins  516 ,  518 . The nonconductive ferrules  512 ,  514  threadably secure and connect conductors to the high voltage pins  516 ,  518  when disposed in openings  520 ,  522  of the connection block  510 . As best shown in  FIG. 42 , additional high voltage pins (and sockets), such as high-voltage connection pin  524  may be present, e.g., to accommodate three phase electrical current. However, a person of ordinary skill in the art will readily recognize that any number of the present high voltage connection pins (as well as sockets  202 ,  204 ) may be present. The instant two-piece socket housing allows easier, more consistent, and more reliable assembly of the high-voltage socket and lead wire; and the lamp socket housing is designed to provide better electrical insulating properties. These better insulating properties are accomplished by providing more insulating material around the high-voltage wire entry way and by adding an additional partial membrane around the socket opening. With a UV lamp installed in the instant module, this membrane creates a longer, more tortuous path to reduce the likelihood of a high-energy short circuit between the lamp connection and the surrounding housing. 
         [0117]    Both lamp connectors (a lamp connector in each of the connection and exhaust ends) are substantially identical in one embodiment of this invention. Additionally, both are spring-loaded against the UV lamp ( FIG. 42 ). The spring action thus encourages higher electrical conductivity through the lamp, socket-pin connections by maintaining full pin-two-socket engagement; prevents the lamp pin from becoming unseated from the socket during aggressive module installation; allows more relaxed dimensional tolerances for manufacturing the UV bulb; and reduces the likelihood of arcing between the pin-to-socket connections and the surrounding end caps. 
         [0118]    Special non-conductive screw-in type ferrules are used as a mechanical back-up to maintain the high-voltage pin and socket connectors better secured in their respective electrical blocks. The pin and socket connectors, normally depending solely on a press-fit into the connection blocks, have, in the past, become unseated or ejected during aggressive module installations. The instant ferrules also permit easier pin and socket replacement in the instance that a conductor is damaged ( FIGS. 23 ,  24 ,  43 ). 
         [0119]    Referring now to  FIGS. 38 ,  39 ,  40 , and  41 , one embodiment of the latch assembly of this invention  286  includes a latch  530  and torsion spring  532  axially secured to a latch rod  534  by retaining rings  536 . The latch  530  defines a retaining groove  538 , within which one arm  540  of the torsion spring  532  is disposed. When secured to the stub bayonets  130 ,  132 , the latch  530  is disposed in the latch mating surface  262 , as described above. When the latch  536  is thusly secured, the bayonets  130 ,  132 , hence connection block assembly  102 , are secured in place. Pressing the latch  530  inwardly (as seen in  FIG. 41 ) displaces the latch from the latch mating surface  262  of each of the stub bayonets  130 ,  132  and allows removal of the connection block assembly  102 . 
         [0120]    The latch rod  534  of this invention has retaining clip grooves  542  at the latch end thereof, rather than at the handle end. With the instant module docked to the connection block of this invention, the retaining clips provide more accurate axial positioning of the water poppet valve components and the electrical connections. As stated above, optimum axial positioning of the water poppet valves provides for maximum coolant flow through the module. Optimum axial positioning of the electrical connections further ensures reliable current flow and minimizes chances for electrical arcing ( FIGS. 38-41 ). 
         [0121]    The spring-loaded docking latch has been widened to transmit more easily over the small gaps between bayonet junctions. The latch features an integral, linear groove designed to retain one leg of the latch torsion spring, thereby providing more consistent assembly and latch operation. Accordingly, the instant latch provides precise axial alignment of the module of this invention to the instant connection block. When utilized with the instant stub bayonets and the instant latch rod, the overall result of the cooperation of these mechanical features results in a precision three-dimensional module-to-connection docking arrangement necessary for optimum module performance ( FIGS. 3 ,  38 - 41 ). 
         [0122]    As can be seen in  FIGS. 15 and 39 , lateral connection end cap passageways  546 ,  548  are laterally defined in the connection end cap  290  and accommodate the stub bayonets  130 ,  132 . The increased diameter of the tapering portion  256  of each of the stub bayonets  130 ,  132  is snugly accommodated within the passageways  546 ,  548 . However, the more distal portions, e.g.,  254 ,  252 , of the stub bayonets  130 ,  132  have a smaller diameter and, thus, slide easily into the connection passageways  546 ,  548 . Consequently, the stub bayonets  130 ,  132  are easily placed within the passageways  546 ,  548  but are laterally secured therewithin due to the quite close tolerance between the diameter of the bayonet sections  256  and the diameter of, and distance between, the passageways  546 ,  548 . 
         [0123]    One embodiment of the shutter assembly  106  of this invention includes left and right connection shutter end caps  570 ,  572 , ( FIG. 10 ), left and right exhaust shutter end caps  574 ,  576  ( FIG. 25 ), a module body  578  ( FIG. 6 ), left and right shutters (extrusions)  580 ,  582  ( FIG. 6 ), negative and positive retainers  584 ,  586  ( FIG. 6 ), a crossover module  588  and cover  590  ( FIGS. 29 ,  30 , and  31 ), an access door  592  ( FIGS. 34 and 35 ), and connection end and exhaust end bearings  596 ,  598  ( FIGS. 16 and 20 ). 
         [0124]    Perspectives of the shutter end caps of this invention may be viewed in  FIGS. 10 ,  25 ,  27 , and  28  and are either identical or are mirror images. Consequently, the right connection shutter end cap  572  will be further explained, corresponding features in the other shutter end caps being either identical or in mirror image. Referring now to  FIG. 9 , the exterior of the shutter end cap  572  is shaped to receive and secure in place the shutter  582 . An exterior opening  612  is defined, and extends from, an exterior surface of the shutter end cap  572 . The opening  612  is dimensioned and disposed to receive a bearing  596 , which will be more fully described below. The bearing, in turn, snugly receives the shutter shaft  332  therewithin. A drive pin slot  614 , with a longitudinal axis  615 , is also defined in a lower outboard portion of the shutter end cap  572 . As can be seen in  FIG. 11 , the drive pin slot  614  is dimensioned to snugly accommodate the drive pin head  362 , as will be more fully explained below. Accordingly, on each of the two cassette-style shutter drive assemblies, a ball headed drive pin is mounted to a shutter shaft arm at the connection end of the module. During operation, the head of this pin engages a drive pin slot in the shutter end cap to rotate each shutter. The ball diameter is larger than the shank diameter of the pin to prevent the shank from contacting any portion of the slot. As shown in  FIG. 11 , several degrees of freedom are therefore provided by the interface of this pin and the shutter end cap slot to allow the shutter to warp and change length without inducing undesired, adverse forces on drive train components. The slot and pin are configured to provide minimal backlash throughout the normal radial swing of the shutter arm and drive pin. Additionally, the slot/pin arrangement of this invention provides for these freedoms of motion: the pin may rotate df 1  along its axis inside the slot  614 ; the pin may slide df 2  into the slot at various depths; the pin may tilt df 3  relative to the centerline of the pin; and the drive pin may contact virtually any portion of the walls of the slot without loss of functionality while nonetheless rotating the shutters. Stated otherwise, the pin-and-slot configuration of this invention allows the shutter end cap to “wobble” and slide along the pin as the shutter assembly warps, expands, and contracts in length. Consequently, binding problems in the drive train components due to imperfect shutter configurations are eliminated or greatly reduced. The variable orientation of the slot relative to the drive pin also relaxes a variety of dimensional and tolerance requirements for pertinent components. This design further prevents damage from occurring to the drive train during rough handling of the instant module, for example, when being lifted or carried by the shutters. The instant drive-pin configuration functions in conjunction with the shutter shaft, exhaust shutter pivot shafts, and shutter end cap bearings to accomplish this functionality. 
         [0125]    Referring now to  FIGS. 16 ,  17 , and  18 , the opening  612  extends into a reservoir  616 . As seen in  FIG. 19 , the reservoir  616  opens into a vertical passageway  618  which, in turn, opens into a horizontal passageway  620 . Accordingly, coolant flowing from the shutter shaft  332  flows horizontally into the reservoir  616 , then flows vertically through the vertical passageway  618 , then flows horizontally through the horizontal passageway  620 . From the horizontal passageway  620 , the coolant flows through a passageway in each of the shutters, as will be described more fully below. Referring now to  FIG. 27 , the interior surface of the shutter end cap  572  defines an O-ring gland  622  surrounding the opening of the horizontal passageway  620  and a relieved surface  624 . The relieved surface (slot)  624  accommodates and secures reflectors in place. 
         [0126]    The shutter end caps include a relieved reflector mounting surface. This feature provides better UV protection for the O-ring located in the shutter body-shutter end cap interface. This feature further allows the length tolerances of the replaceable reflector strips to be less critical. By using the instant shutter end caps, reflectors may now be removed and installed without removing the shutter end cap and without breaking the fluid-tight integrity of the shutter assembly. Only the retaining strip needs to be removed to exchange a reflector. In-situ, carefully made reflector fitment is no longer necessary because convenient pre-cut reflectors may be used. With the end caps of this invention assembled to the shutter extrusion, the relieved surfaces of the end caps fit flush to the inner surface of the shutter extrusion to produce an uninterrupted, full length, properly shaped reflector supporting surface ( FIGS. 27 ,  28 ). Accordingly, printing press down time may be greatly reduced, due to the advantages of the quick change feature present in the reflectors of this invention. Using the instant reflectors may also be an important factor of the efficiency of the UV curing process. It has been reported that, with the use of clean and properly shaped reflectors, somewhere between 60% and 80% of the UV light striking the substrate is reflected light. 
         [0127]    The present shutter end caps are made from aluminum, rather than stainless steel previously used. Accordingly, the instant shutter caps minimize galvanic and corrosive action occurring when the instant shutter end caps are mounted to the extruded aluminum shutter body. Shutter end caps are further fabricated from a single piece of material, rather than the multiple pieces previously used. Fashioning the instant shutter end caps eliminates several intricate welding operations previously necessary. The shutter end caps of this invention are fabricated using custom made tools to produce a special coolant passageway. This passageway includes an integral reservoir, which helps cool the stem of the UV lamp. The stem of the UV lamp must be maintained several hundred degrees cooler than the main body of the lamp ( FIGS. 18 ,  27 ). 
         [0128]    As seen in  FIGS. 1 ,  2 ,  4 ,  6 ,  7 , and  13 , the module body  578  unitarily, or otherwise integrally, defines an upper member  630  and lateral members  632 ,  634 , which depend from the upper member  630 . The lateral members  632 ,  634  respectively define module body lateral passageways  636 ,  638 , which are continuous with the respective passageways  546 ,  548  of the connection end cap assembly  102  and which accommodate the stub bayonets  130 ,  132  therein ( FIG. 15 ). As seen in  FIG. 39 , defined in a central portion of the module body  578  are coolant passageways  640 ,  642 . Referring again to  FIGS. 6 and 7 , the upper portion of the module body  578  defines a crossover module opening  644 , which accommodates the crossover module  588  as more fully explained below. 
         [0129]    As best viewed in  FIGS. 6 ,  7 , and  13 , the shutters  580  and  582  attach to the end caps and have therewithin coolant passageways  650 ,  652 . The coolant passageways  650 ,  652  align with, and receive coolant from, the horizontal passageways  620  of the instant shutter end caps. Attached to lower edges of the shutters  580 ,  582  are respective negative (female) and positive (male) reflector retainers  584 ,  586 . The negative reflector retainer  584  terminates in extensions  650 ,  652 , thereby defining a gap  654 . The positive reflector retainer  586  terminates in a beveled tip  660 . Reflector mounts  662 ,  664 , are formed at the inboard ends of the shutters  580 ,  582  and reflector mounts  666 ,  668  are formed at the outboard ends of the retainers  584 , 586 . These mounts secure The reflectors utilized during operation by securing the edges of the reflectors therewithin. To replace these reflectors, the retainers  584 ,  586  are removed by removing the fasteners used to secure them in place, the reflectors are then removed from the mounts  662 ,  664 , replacement reflectors are installed, and the retainers are then secured in place as shown by the fasteners. 
         [0130]    Previously, each shutter assembly was outfitted with either a “male” or “female” reflector retainer strip mounted to the outer edge of the shutter extrusion. When the shutters were closed, the male and female profiles of the retainer strips mated together to effectively block the direct path of light out of the module. In the design of this invention, the original female V-shaped (negative) reflector retainer profile is modified to define a shallow U-shaped channel. This new shape prevents shutter-to-shutter binding when closed shutters are warped from heat or from other causes of shutter-to-shutter misalignment ( FIGS. 6 ,  7 ). The male, V-shaped “positive” reflector retainer profile retains its original profile. Consequently, when the shutters are closed and the shutter retainer profiles are mated together, the U-shaped channel does not affect the ability of the closed shutters to block light. 
         [0131]    Referring now to  FIGS. 29 and 30 , the crossover module  588  defines a coolant reservoir  670  opening into coolant ports  672 ,  674 . Lateral portions of the crossover module  588  define passageways  676 ,  678 , which are continuous with the module body passageways  636 ,  638  in assembly end cap passageways  546 ,  548  to thereby accommodate the stub bayonets  130 ,  132 . The horizontal, planar portion  682  of the crossover module  588  defines a plurality of, e.g., eight threaded apertures  680 . Operationally, the crossover module  588  is disposed within the crossover module opening  644  of the module body  578 . The module body cover  590  conforms to the shape of the horizontal planar portion  682  of the crossover module  588  and defines a plurality of, e.g., eight apertures  686 . The apertures  686  align with the apertures  680  present in the crossover module  588 . Accordingly, the module body cover  590  is secured in place by extending fasteners through the apertures  686  and threading the fasteners into the apertures  680 . 
         [0132]    The coolant crossover feature is incorporated into the upper module cover to ease manufacturing and assembly issues. The crossover cavity features a substantial reservoir to better cool the lamp seal, shutter sensors, lamp socket assembly and shutter assemblies ( FIGS. 29 ,  30 ). 
         [0133]      FIGS. 34 ,  35 , and  36  show an access  690  and access door  592  of this invention. The access  690  is defined at lower portions of each lateral side of the connection end cap assembly  104 . The access door includes respective upper and lower dovetailed edges  694 ,  696 , which terminate about midway at  698 ,  700 . A worm shaft access hole  702  is defined in the access door  592  as well. Proximate upper and lower peripheries of the access  690  are complementary, slotted portions  704 ,  706 . The dovetailed edges  694 ,  696  are accommodated, and slide within, the slotted portions  704 ,  706 . 
         [0134]    The shutter drive train access doors have been designed to allow them to be removed with a minimum of module disassembly. A portion of the upper and lower dove tail edges of the access doors has been removed, thereby allowing the doors to be removed after being slid a short distance. Accordingly, the only component necessary for removal prior to access door removal is the module bottom cover in one embodiment. Once the doors are removed, the shutter drive assemblies may be “timed” (synchronized) as required without further disassembly of other module components ( FIGS. 34-37 ). The fasteners securing the two-piece collar to the shaft are easily accessible. Initial timing of the shutters may be quickly accomplished with the shutter drive assembly in place and without extensive disassembly of module components. After removing the access doors, an Allen wrench inserted through access holes can quickly loosen and retighten the fasteners on the collars or worm shaft to provide quick and easy shutter timing adjustments. Each of the two shutter drive assemblies may be independently adjusted in this manner to help simplify and finely adjust shutter timing adjustments as desired ( FIGS. 8 ,  34 - 37 ). 
         [0135]    As shown in  FIG. 9 , the bearing  596  is disposed in the opening  612  of the connection and exhaust shutter end cap shown of this invention.  FIG. 19  depicts the bearing  596  disposed in the right connection shutter end cap  572  and  FIG. 20  shows the bearing  596  disposed in the right exhaust shutter end cap  576 . The orientation of the bearing  596  in the right exhaust shutter end cap  576  is rotated 180 degrees from the orientation of the bearing  596  in the right connection shutter end cap  572 . In either case, the bearing  596  has a housing  710  defining respective outer and inner glands  712 ,  714  and a bearing surface  716  therebetween. Respective outer and inner seals  718 ,  720  are accommodated within the outer and inner glands  712 ,  714 . In the case of the left and right connection shutter end cap shown  570 ,  572  each of the bearings  596  receives one of the shutter shafts  332  to achieve a fluid tight connection as the connection end caps are rotated during operation. 
         [0136]    The bearing arrangement of this invention provides for nominal flexing, thermal expansion/contraction, warpage, and dimensional variations of the shutter assembly without sacrificing fluid-integrity or inducing undesired forces on seals and shutter drive train components. The instant bearing features a narrow, centrally located load-bearing surface that is sealed on either side by a pair of integral seal glands fitted with O-rings. By virtue of their elasticity, these O-rings also provide a mechanical means to distribute the bearing loads. The outer O-ring  718  also serves as a wiper to prevent debris from entering the bearing and seal areas. 
         [0137]    The shutter shafts and the exhaust shutter pivot shafts function as bearing surfaces for the shutter end cap bearings and as O-ring sealing surfaces for the shutter end cap bearing seals. In both cases, the shutter end cap shown may be displaced with several degrees of freedom. 
         [0138]    The instant bearing arrangement provides several degrees of freedom for the shutter and caps as more fully described above. The instant bearing also functions as a heat sink and a heat transfer element, again cooperating with other features to maintain module components at cooler temperatures ( FIGS. 5 ,  19 ,  20 ). 
         [0139]      FIGS. 20 ,  25 ,  26 , and  28  depict the exhaust end cap assembly  108  of the instant invention, including a lamp connector  730 , a lamp connection assembly  731 , an exhaust shutter shaft  732 , a fluid passageway including a sacrificial anode  738 , and an end plate  740 . The lamp connector  730  may be substantially identical to the lamp connector  470  as shown in  FIGS. 21 and 22 . In  FIG. 28 , the lamp connector  730  is shown operably mounted between the exhaust end caps  574 ,  576 . The exhaust shutter shaft is rotatably disposed within the bearing  596  of each of the exhaust shutter end caps  574 ,  576 . The exhaust shutter shaft opens into the reservoir of each of the exhaust shutter end caps  574 ,  576 , as well, then opening into a vertical passageway  734 . The vertical passageway  734  extends upwardly joining a horizontal passageway  736 . The horizontal passageway  736  opens into one of the module body passageways  640 ,  642 . The sacrificial anode  738  functions as a coolant plug and threads into a lower portion of the vertical passageway  734 . 
         [0140]    In one embodiment, the coolant plugs in the module exhaust end cap are modified (shortened) sacrificial zinc (or manganese) anodes to combat corrosion in coolant passageways. The sacrificial anodes are installed directly in the flow path inside the module for maximum effectiveness and have a chamfered or radiused end for maximum exposure to coolant flow ( FIGS. 25 ,  26 ). The contemplated coolant utilized in the instant invention, as well as other UV modules, is either locally available water or water-polyethylene glycol mixtures. Locally available water is often an electrical conductor due to concentrations of sodium, calcium, magnesium, and iron cations. Water-polyethylene glycol mixtures are electrical conductors as well. Accordingly, galvanic corrosion presents an ongoing problem by causing corrosion of the coolant conductive passageways. Moreover, the high temperatures present during operation accelerate the chemical reactions of galvanic corrosion, resulting in coolant leakage where corrosion reactions have eroded coolant passageways. Coolant leakages, especially in proximity to the UV lamp or electrical connections, can cause extensive damage due to electrical arcing. Galvanic corrosion occurs when a first metal contacts a second metal, both exposed to an electrolyte. Since both the first and second metals are conductors, the first metal will corrode preferentially if the first metal has a greater (more negative) galvanic potential than the second metal. In the case in point, zinc has a greater galvanic potential than aluminum, the predominant metal exposed to the instant coolant solution. Therefore, the zinc anode of this invention will corrode preferentially to any aluminum components of the coolant pathway. Because the instant zinc anode may be provided in the form of a threaded plug, the instant zinc anode may be easily and quickly replaced periodically when sufficiently corroded to ensure that the predominant aluminum pathways remain intact, uncorroded, and leakage free. 
         [0141]    In one embodiment, a coolant pathway present in the instant UV module begins when coolant enters the right fitting  164  and exits the left fitting  162 . However, entry via the left fitting  162  and exit via the right fitting  164  or alternating the foregoing two alternatives are contemplated to be within the scope of the instant invention. In any of the foregoing scenarios the coolant pathway would encounter elements described above, albeit in different sequences. In the first scenario, the coolant enters the right fitting  164  ( FIG. 4 ) and flows through the right poppet valve  240  ( FIG. 16 ). From the right poppet valve  240 , the coolant flows through the sleeve bushing  420 , then through the right shutter shaft  332  ( FIG. 5 ). From the right shutter shaft  332 , the coolant then flows through the right connection shutter end cap reservoir  616  ( FIG. 16 ), then through the right connection shutter end cap vertical and horizontal passageways  618 ,  620  ( FIG. 19 ), then through the right shutter passageway  652  ( FIG. 6 ). From the right shutter passageway  652 , the coolant flows through the right exhaust shutter end cap horizontal and vertical passageways and into the reservoir thereof (not shown). From the right exhaust shutter end cap reservoir, the coolant flows through the right exhaust shutter shaft  732 , though the vertical and horizontal passageways  734 ,  736  ( FIG. 26 ) and into the module body coolant passageway  642  ( FIG. 39 ). After flowing through the module body coolant passageway  642 , the coolant flows through the crossover module  588 , though port  674 , reservoir  670  and port  672  ( FIG. 30 ) and into the module body passageway  640  ( FIG. 39 ) to begin a passageway in the left components of the instant UV module which is essentially a reverse of the passageway to the right components thereof In this reverse passageway, the coolant flows through the module body passageway  640  ( FIG. 39 ) and into the left horizontal and vertical passageways (not shown). While many of the components of the left fluid passageways are not depicted, these components are substantially similar or identical to those shown with respect to right fluid passageways. From the vertical passageway  734 , the coolant flows through the left exhaust shutter shaft and into the left exhaust shutter end cap, where the coolant flows through the end cap reservoir and vertical and horizontal passageways. From the left exhaust shutter end cap horizontal passageway, the coolant then flows through the left shutter passageway  650  ( FIG. 6 ) and into the left connection shutter end cap reservoir (not shown). After flowing through the left connection shutter end cap reservoir, the coolant then flows through the horizontal and vertical passageways thereof and into the left shutter shaft  332  (not shown). From the left shutter shaft  332 , the coolant then flows through the sleeve bushing  420 , poppet valve  240 , and exits via the left fitting  162  (not shown). 
         [0142]    Referring now to  FIGS. 44 ,  45 ,  46 , and  47 , another embodiment of the instant shutter assembly of this invention is depicted at  750 , having respective negative (female) and positive (male) retainers  752 ,  754 . The other components of the shutter assembly  750  may be similar or substantially identical to those discussed previously. The negative retainers  752  defines a terminal C-channel or slot  760  in a similar manner to the negative retainer  584  discussed above. However, in contrast to the positive retainer  586 , the positive male retainers have a plurality of alternate respective lower and upper cutouts  762 ,  764  straddling the tip  766  thereof. As can be seen, the remaining, or non-cutout portions  768 ,  770  of the positive retainer  754  abut the upper or lower extensions  772 ,  774  of the negative retainers  752 , thereby leaving a gap between the tip  766  of the positive retainer  754  and the surface of the C-channel  760  to allow airflow into the interior of the shuttle assembly from the exterior, to thereby further assist in cooling. Stated otherwise, the gap between the lower cutout  762  and the lower extensions  772 ,  774  may be considered as a lower channel portion  778 ; the gap between the positive retainer tip  766  and the surface of the C-channel  760  may be considered as an intermediate channel portion  780 ; and the gap between upper cutout  764  and the upper extensions  772  may be considered as an upper channel portion  782 . The lower, intermediate, and upper channel portions  778 ,  780 ,  782  being continuous, a plurality of air channels are thereby defined to further assist in cooling the interior of the instant UV module of this invention. 
         [0143]    When a printing press is operating, the shutters of this invention are rotated to an open position by the shutter drive train ( FIG. 6 ). The very high energy light (a combination of visible, infrared, and ultraviolet wavelengths) is generated from a lamp. A proportion of the light is reflected and another proportion directly impinges the inked substrate. The shutters are designed with a special shape to reflect and aim as much light energy toward the substrate as possible so that the UV wavelengths will “cure” (dry) the UV-reactive ink. 
         [0144]    Under certain conditions, the shutters must be closed ( FIG. 7 ). The outer edges of each of the shutters are equipped with either a positive (male) or a negative (female) profile. These profiles mate together when the shutters are closed to block the passage of light to the substrate being printed by the press. A shutter assembly that has stalled in a non-fully-closed position (usually due to shutter warpage, drive train bind-up, or motor failure) has been known to allow a powered-up lamp to ignite the substrate. 
         [0145]    During normal operation, a water or water/glycol coolant mixture is circulated through the module body and through both shutter assemblies to remove excess heat and control the amount of shutter warpage and expansion. The instant module body and shutter assemblies are made from extruded aluminum with integral coolant passageways. There are numerous places throughout the module assembly where static and dynamic O-rings seals may be used to attempt to prevent the coolant from leakage. In the past, leakage problems have been fairly common. In the module design of this invention, the O-ring seal and gland designs eliminate, or greatly reduce, coolant leakages. However, most coolants are good conductors of electricity and due to the close proximity of leakages to the high-voltage electrical connections within the module of the prior art, these leakages have often caused and escalated component damage due to electrical arcing. 
         [0146]    The special high-energy UV lamps require high-voltage and fairly high current, e.g., up to  3000  volts and up to  17  amps. The electrical connections conducting this electrical current must retain electrical conduction properties and must be well insulated from surrounding components ( FIGS. 21-24 ,  42 ,  43 ). In the past coolant leakages, electrical leakages, pin and socket erosion and pin-to-socket alignment problems between the module and the connection block have been causes of failure in the electrical connections. 
         [0147]    Because numerous modifications of this invention may be made without departing from the spirit thereof, the scope of the invention is not to be limited to the embodiments illustrated and described. Rather, the scope of the invention is to be determined by the appended claims and their equivalents.