Abstract:
The present invention provides a light emitting fixture or luminaire that is sealed from the outside and possesses no major voids within. This arrangement protects the light emitting elements, in a preferred embodiment consisting of Light Emitting Diodes (LEDs) from the elements as well as keeping pests and vandals from inhabiting and/or causing damage to the luminaire. The light emitting elements have lenses that add high impact resistance, thus improving safety and reliability. The luminaire is easy and quick to install; it can be installed using only one hand tool, and can easily be handled with thick gloves.

Description:
BACKGROUND 
       [0001]    The present invention pertains to the field of outdoor lighting in particular to roadway and outdoor luminaires for space lighting. 
         [0002]    Recent increases in energy costs have driven a need for more energy and maintenance efficient devices. This includes applications for lighting fixtures in the general illumination outdoor market, including but not limited to roadway and outdoor space lighting. In addition to being energy efficient, Light Emitting Diodes LED&#39;s are more maintenance efficient in that they possess higher inherent reliability. This effectively lowers the Mean Time Between Failure (MTBF) when compared to legacy High Intensity Discharge (HID), incandescent, and fluorescent lighting filament components. However, simply swapping out one for the other is not a practical solution in most cases. The outer housing, optics, and support circuitry is as important as the LEDs themselves in providing a total support solution for both the maintainer and end user. 
         [0003]    Life Cycle Costing (LCC) analyses show that maintenance actions usually count for some of the highest cost drivers, if not the single highest cost driver in supporting a given system over time. Such is also true for outdoor lighting systems. It is therefore desirable to have a lighting system with the highest possible reliability without adding significant per unit cost. 
         [0004]    Current electrical factors that cause outdoor light systems to fail include but are not limited to; failure of the bulb filament itself, failure of the ballast and support circuitry, failure of the photocontrol, and failure of the transformer. Other factors include but are not limited to; weather related destruction such as damage caused by hurricanes and tornados, pest infestation—such as squirrels chewing through wires, and vandals—such as people shooting air guns or throwing rocks for the purpose of intentional destruction of lamp fixtures. All of these factors contribute to reducing the operational availability of the given population of lights that maintainers must support. The present invention addresses these issues. 
         [0005]    A typical roadway or similar outdoor luminaire includes, among other things, of a house, a lamp providing illumination, and a means of attaching the housing to a pole or other structure to elevate the luminaire above the roadway, parking lot, or similar area to be illuminated. 
         [0006]    One conventional approach is to use a luminaire known as a “cobra head” due to its reptilian shape.  FIG. 1  shows a side view of a typical prior art “Cobra Head” style High Intensity Discharge (HID) street lamp assembly or luminaire  79  as installed on a utility pole  92 . An incoming wire enters a transformer  80  that lowers the voltage to 120-240 Volts AC. This powers the HID lamp  10  (shown in  FIG. 3 ) and causes rays of light  91  (shown in  FIG. 2B ) to illuminate the area below the lamp. Typically, this area is a roadway, intersection of roadways, sidewalk, park, parking lot, or the like. 
         [0007]    A close up view of the prior art cobra head street lamp assembly  79  is shown in  FIGS. 2A and 2B . Photocontrol  22  turns the light on and off according to the amount of ambient light. Such photocontrols or photosensors are well known in the art and will not be further discussed. Metal pole arm  14  can be seen entering into the luminaire  79 . A dispersion lens  16  can be seen in  FIG. 2B . A section line A-A is drawn on  FIG. 2A  showing the parting line for a detailed section views in  FIGS. 3 and 4 . 
         [0008]      FIG. 3  shows section A-A in a semi-exploded view. This is done for clarity reasons to better illustrate how the internal components fit together. In this figure, one can see that a pole arm  14  typically enters into a hollow top housing assembly  12  via an oversized hole  39  and up against a pole arm end stop  30  usually cast into the top housing assembly  12 . Power wires then connect to a terminal block  28  on the inside and then a transformer  19  and igniter  18  before connecting to an HID bulb base  31  and lamp  10 . Lamp  10  is sometime referred to as a “bulb.” The transformer  19  and igniter  18  in this case represent an HID “starter” assembly, but can comprise of different electrical components such as circuit boards and other common components known to the art. The HID lamp  10  is then powered and “lit up” due to the controlled inrush current of the starting mechanism. Rays of light then exit the HID bulb and reflect off of the reflecting surface  29  of reflector housing  11 . These rays are then dispersed through lens  16  to the ground to form an illuminated pattern. 
         [0009]    Lens  16  is mechanically held in place by the bottom housing  13  which both opens rotationally around and is held in place by a hinge joint  33  &amp;  34  and a spring loaded latch  20  to the top housing  12 . A fiberglass or similar based gasket  17  is sandwiched in between the lens  16  and the HID bulb reflector  11 . This helps seal the two pieces and prevents debris material and other objects from getting into the cavity and obscuring the lens. The top housing  12  is secured to the pole arm via a clamp  15  that is attached by turning one or more threaded fasteners  24  to a desired torque level into mating, internally threaded stud posts  32  that are usually cast into and part of the top housing  12 . This keeps the clamp secured and the fasteners from backing out. It also prevents the HID lamp assembly  79  from shifting on the pole arm  14 . 
         [0010]      FIG. 4  shows section A-A in an assembled view. Some of the common pests found inside prior art cobra head street lamps are shown in  FIG. 4 , namely squirrel  26  and wasp  27 . For instance, a squirrel can easily enter the housing via the center of a pole arm  14  or through the oversized gap  39  surrounding the pole arm  14 . These pests are problematic in that they can contribute to the premature failure of the HID fixture causing costly unscheduled maintenance and can attack the maintainers as they are trying to perform maintenance on the fixture. 
         [0011]    These pests find the inside of a streetlamp an ideal nesting habitat as it offers protection from the weather and predators. The flying squirrel&#39;s body is highly flexible and can easily squeeze into tight places. The flying squirrel, as with many rodents, has a tendency to chew through various objects with sharp, elongated teeth. The electrical wiring within the lamp is particularly vulnerable. Once a wire is chewed through, the center conductor is separated and exposed. In addition to causing the lamp to fail, this condition can cause a short to the housing  12  &amp;  13 . This can lead to a potential fire and electrical hazard. Squirrels can chew through and remove the fiberglass gasket  17  for nesting material. These animals can also create a mess by emitting feces and urine inside the lamp, which is unsanitary and can obscure the lens  16 . It is therefore desirable to create a lamp that resists these types of pests. 
         [0012]    Another common pest is the wasp  27  of which there are many varieties. The wasp is highly territorial and protects itself and its nest by injecting venom via stinger. Most varieties find the inside of a streetlight a desirable habitat for nesting purposes. In addition to entering into the lamp through the hole or gap  39  as the flying squirrel, the wasp can also enter through the parting line  38  formed by the top and bottom housings  12  &amp;  13 . Many wasp species form colonies and build hive nests  36  which are usually attached to the roof of the cavity inside the lamp. These nests can be large and the wasps inside are very aggressive to anything they see as a threat or intruder to their hive nest. They use their painful stinger to inject venom into anything they perceive as threatening their nest. They also simultaneously emit chemical signals to the other wasps in the nest to swarm and “attack” any threat in the area of the nest in a group. This is a common nuisance experienced by maintainers who frequently get stung trying to access a lamp fixture. Due to the fact that wasp stings are very painful and potentially lethal to those that are allergic to wasp venom, it is therefore desirable to create a lamp that resists these types of pests as well. 
         [0013]    Current pest countermeasures such as makeshift screens are usually ineffective as persistent pests can chew through or squeeze around these crude devices. 
         [0014]    The use of LEDs to replace common glass envelope lamps or bulbs is also known in the illumination arts. Earlier methods for packaging LED&#39;s includes a base containing five LED dies surrounded by a clear epoxy that allows rays of light to pass through. At the same time, this clear epoxy seals the LED&#39;s from moisture and other contaminants such as disclosed in U.S. Pat. No. 6,812,481. 
         [0015]    U.S. Pat. No. 7,267,459 provides a hollow extruded enclosure surrounding one or more LED&#39;s and covered by a clear transparent sheet for the purpose reducing the ability for moisture and other contaminants from entering internally to the assembly. 
       SUMMARY 
       [0016]    In contrast to the above-described conventional approaches, embodiments of the invention are directed to a light emitting fixture or luminaire that is sealed from the outside and possesses no major voids within. This arrangement protects the light emitting elements, which may consist of Light Emitting Diodes (LEDs) with optical lenses, from the elements as well as keeping pests and vandals from inhabiting and/or causing damage to the luminaire. The optical lenses have high impact resistance, thus improving safety and reliability. The luminaire is easy and quick to install; it can be installed using only one hand tool, and can easily be handled with thick gloves. 
         [0017]    One embodiment of the invention is directed to a luminaire, comprising a thermally conductive housing and a plurality of light emitters encased in a reflective solid matrix. Each light emitter comprises a light source and a lens element coupled thereto. The luminaire is mounted on a standard street lighting pole arm by means of a pole arm mounting formed integral to the housing. The pole arm mounting includes one or more captivated screw/band clamps to attaching the luminaire to the pole arm 
         [0018]    A connector mounted on the pole arm end of the housing and adjacent to the pole arm mounting includes a plurality of conductors disposed to conduct electricity from a plurality of terminals located outside the housing to a plurality of connection points located inside the housing. The pole arm surrounds the connector and butts against the end of the housing when the luminaire is attached to the pole arm. 
         [0019]    In an alternate embodiment, the luminaire housing comprises a heat sink. There may also be located within the housing a power supply that is thermally coupled to the housing and electrically coupled to the external (line) power and the light emitters. The electrical coupling from the external line power may, in some embodiments, be by means of a connector. This connector may have a pair of edge protrusions disposed in an I-shape that separates the wire terminals to prevent short circuits. 
         [0020]    In a further embodiment, the connector may instead have a pair of edge protrusions disposed in a back-to-back C-shape for separating the terminals with a greater degree of protection from short circuits. And in yet a further alternate embodiment, the connector may be formed of an insulating material that substantially encloses the external terminals. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    The foregoing and other objects, features and advantages of the invention will be apparent from the following description of particular embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. 
           [0022]      FIG. 1  illustrates a prior art luminaire and how it is installed on a pole. 
           [0023]      FIGS. 2A and 2B  illustrate the parts of a prior art luminaire in top and side views, respectively. 
           [0024]      FIG. 3  shows an exploded section view of a prior art luminaire. 
           [0025]      FIG. 4  shows an assembled section view of a prior art luminaire infested with pests. 
           [0026]      FIGS. 5A through 5E  illustrates one embodiment of the present invention showing top, side, bottom, section, and rear views of the entire assembly. 
           [0027]      FIG. 6A  illustrates a close-up section of one embodiment of the present invention detailing a plurality of LEDs mounted to a thermally conductive board which is mounted to a thermally conductive housing.  FIG. 6B  is an expanded view of one such LED. 
           [0028]      FIG. 7  illustrates an exploded, isometric view of an exemplary embodiment of the present invention as installed in the field. 
           [0029]      FIG. 8  shows an isometric view of an exemplary embodiment connected to its electrical supply leads, with the pole arm removed. 
           [0030]      FIG. 9  shows an exemplary embodiment mounted on the pole arm. 
           [0031]      FIG. 10  shows a section view of the power connection point, according to one embodiment of the present invention. 
           [0032]      FIGS. 11A-11B ,  12 A- 12 B, and  13 A- 13 B show several alternate embodiments of the power connection point. 
       
    
    
     DETAILED DESCRIPTION 
       [0033]    The present invention is a novel pest resistant streetlamp assembly that is also more affordable and easier to install and maintain than current lighting technology. This is accomplished by using a completely sealed lamp assembly with no large internal voids and with an innovative mounting technique to accommodate various pole arm diameters. 
         [0034]      FIGS. 5A ,  5 B,  5 C,  5 D, and  5 E show the embodiment of said invention from top, side, bottom, section, and rear views, respectively. This embodiment of the invention will hereto be referred to as the pest resistant lamp (PRL). The entire assembly  86  consists principally, but not exclusively, of a main housing  40  that is machined, cast, or stamped from a thermally conductive metal such as (but not limited to) zinc, copper, aluminum, or alloys thereof. This serves as a structural “skeleton” of the lamp as well as to draw heat away from the power supply and Light Emitting Diodes (LEDs, or singularly, LED). LEDs are preferable over HID bulbs as they generate less heat during operation and are more power efficient. 
         [0035]      FIG. 5A  shows the top view of the PRL housing and illustrates the general shape of the luminaire assembly. The stainless steel screw/band mounting clamps  61  (referring to  FIG. 7 ) is removed for clarity. Radiating fins  83  allow excess heat to escape from the assembly. A pour hole  53  is drilled out or cast into the top of the assembly. A photocontrol receptacle  42  for holding an industry standard photocontrol is also shown. This may be, in some embodiments, the same photocontrol receptacle as commonly used in the prior art. A protrusion  82  is shown on the side of the housing  40 . Protrusion  82  is hereto referred to as the “pole arm to housing mounting arm.” The pole arm to housing mounting arm  82  mounts to the top of the incoming pole arm (not shown) and serves as a support for the stainless steel screw/band clamp (not shown for clarity) known in the prior art. Two clamp grooves  81  are shown in the pole arm to housing mounting arm  82 . A clamp-retaining bracket  63  is held down via a threaded fastener  64 . Two top support fins  62  provide structural support to the pole arm housing mounting arm  82  in addition to keeping the clamp retaining bracket from rotating around pole arm housing mounting arm  82 , since the clamp retaining bracket is only held down by one fastener  64 . 
         [0036]      FIG. 5B  shows the side view of the PRL assembly. An “I” shaped power connection point (or simply “connector”)  45  is shown underneath the pole arm housing mounting arm  82 . Two clamp gaps  69  between pole arm to housing mounting arm  82  and clamp retaining bracket  63  are also seen in this view. The clamp gaps are each large enough to accommodate one or more stainless steel screw/band mounting clamps (not shown) and to allow rotational motion of the clamp for installation purposes, but not to allow the clamps to escape or fall off. This allows the clamps to be held in a “captive” state. A flat surface  55  perpendicular to the “I” shaped connector  45  allows for flush mounting of the end of the pole arm so that pests have no gaps near the lamp assembly from which to enter or hollow overhangs to create nests. The bottom surface  56  is, in an exemplary embodiment, flat and perpendicular in relation to flat surface  55 . In alternate embodiments, however, there needs be no restriction on the shape of bottom surface  56 . 
         [0037]    Although an embodiment using two clamps  61  is described, those skilled in the art will realize that any number of clamps can also be used. Accordingly, the invention is not limited to any particular number of clamps. 
         [0038]    Although “I” shaped power connection point or connector is described, those skilled in the art will realize that connectors other than an “I” shaped connector can be used. Accordingly, as will be discussed further below, the invention is not limited to any particular type or shape of power connection point. 
         [0039]      FIG. 5C  shows the bottom (i.e., the ground- or street-facing side) of the PRL assembly  86 . The bottom of encapsulated power supply  44  is shown in the center of the PRL. The bottom of the power supply  44  is flush or near flush with the bottom  56  of the main housing  40 . This helps to form cavities  71  in the bottom of the housing for mounting an LED MCPCB strip  49 , which are then back filled with white reflective epoxy. Each LED MCPCB strip  49  contains a plurality of LED lens assemblies  48 , discussed in further detail below with reference to  FIGS. 6A and 6B . 
         [0040]    Encapsulated power supply  44  may be any commercially available power supply suitable for adapting the input line voltage to the voltage or voltages required to operate LEDs  50 . Alternatively, a special purpose power supply may be used to optimize the power consumption of the luminaire. As the type, specification, and design of such a power supply, as well as methods of encapsulating or otherwise weatherproofing the same, are well known in the art, the details of the power supply  44  will not be further discussed herein. In a further alternate embodiment, the functions of power supply  44  may be distributed to and located on each LED MCPCB strip  49 , eliminating the need for a separate power supply device. In such an embodiment, wire harness  72  connects from connector  45  directly to each LED MCPCB strip  49 . 
         [0041]    Although two LED MCPCBs  49  are shown, one of ordinary skill in the art will appreciate that a single LED MCPCB  49  or three or more LED MCPCBs  49  (with corresponding cavities  71  formed in the bottom  56  of min housing  40 ) may also be used, depending on the light output desired. Accordingly, the invention is not limited to any particular number or arrangement of LED MCPCBs  49  or cavities  71  within housing  40 . Similarly, the invention is not limited to any particular number or arrangement of LED lens assemblies  48  within each LED MCPCB  49 . 
         [0042]    The power supply  44  is mounted to the main housing using threaded, riveted, or other fasteners  70  commonly known in the art. The power supply can also have a thin coating of epoxy or other weatherproof material for additional protection, preferably a white reflective epoxy. Such a coating will resist light arms fire from air rifles and slingshots that vandals typically use to intentionally destroy streetlights as epoxy has high shock absorption properties. Even if an individual LED lens  48  were penetrated, it would only short out the individual LED, which is wired in parallel, thus not causing the whole lamp to go dim. This would make it extremely difficult and frustrating, albeit not impossible, for a vandal to completely destroy and dim out the lamp. 
         [0043]      FIG. 5D  shows a section view C-C (referring to  FIG. 5A ) of the PRL  86  with clamps  61 , clamp retaining bracket  63 , and fastener  64  removed for clarity. The “I” shaped connector  45  feeds through the main housing  40  and connects to the photocontrol receptacle  42  and encapsulated power supply  44  via an internal wire harness  72 . The encapsulated power supply  44  is mounted to the housing via standard fasteners (not shown). A bead of thermal epoxy compound or adhesive  51  is placed around the perimeter of the power supply  44  to bond it to a shelf that is formed by the housing  40 . This seals off and creates an internal cavity that contains internal wire harness  72 . This internal cavity is then filled with an electrically insulating, thermally conductive epoxy compound  52  via a fill hole  53 . This effectively removes all internal voids from the cavity, preventing pests from entering as well as moisture from causing damage to the wiring. 
         [0044]      FIG. 5E  shows a rear view of the PRL, looking from the pole arm into the luminaire  86 . The “I” shaped connector  45  is shown from the end that first enters the hollow portion of the pole arm (not shown for clarity). The “I” connector mounting fasteners  73  are shown at both the right and left sides of the “I” connector  45 . These fasteners  73  are mounted flush to the rear housing surface  55 . Any of a number of flush-mounting fasteners well known in the art may be used. This ensures that the end of the pole arm  14  remains flush to the housing surface. Outlines of the minimum and maximum pole arm diameters are shown as phantom lines  54 . Pole arm sizes vary, so it is important for the mounting connection to accept a wide range of sizes. 
         [0045]      FIG. 6A  illustrates a close-up along Section B-B of  FIG. 5A  of one embodiment of the present invention detailing a plurality of Light Emitting Diodes (LEDs)  50  mounted to a thermally conductive MCPCB  49  which is mounted to thermally conductive housing  40 . The Light Emitting Diodes are placed under precision optical lenses  48  which are surrounded by a white reflective epoxy  47 . 
         [0046]    In particular,  FIG. 6A  shows a cross-section of one of the LED MCPCB arrays  49 . A cavity  71  is formed in the housing  40  by any of a number of means well known in the metalworking arts, such as casting or milling. A plurality of LED&#39;s  50  are mounted to a Metal Core Printed Circuit Board (MCPCB)  49 . Clear acrylic, polycarbonate, Lexan® or similar lenses  48  cover each of the LED&#39;s  50  and direct the light in a specific pattern. (Only three lenses  48  are shown for clarity; all LEDs  50  are covered by such lenses.) The entire cavity  71  is then filled with a white reflective epoxy  47 . The epoxy is filled until it is flush or near flush with surface  56 . The smooth glossy surface of the epoxy and the overall flatness of the bottom deter nest building by wasps in addition to covering the LED MCPCB array and protecting it from weather elements. 
         [0047]      FIG. 6B  shows more detail of a LED lens assembly  57 . An LED  50  emits light through a typical LED lens  48  commonly used in the art. While very efficient, errant light rays  58  can exit through the side of the LED lens  48 . The white glossy epoxy  47  reflects these errant rays out of the top of the lens  48  (which is not covered by epoxy  47 ) thereby making the lens more efficient. 
         [0048]      FIG. 7  shows an isometric exploded view of one embodiment of the present invention, with particular detail in one method of fastening it onto a pole arm  14 . Wires  59  and  60  enter through the center of the pole arm  14  and are connected to “I” shape connector  45  through the clamps  61 . Although only two wires  59 ,  60 , and two clamps  61  are shown, one of ordinary skill in the art will recognize that multiple wires and/or multiple clamps may also be used. Accordingly, the present invention is not to be construed as limited to a specific number of wires and/or clamps. Also, although a stainless steel screw/band clamp is described in one preferred embodiment, those skilled in the art will realize that clamps other than screw/band clamps or made of materials other than stainless steel can be used. Accordingly, the invention is not limited to any particular type of clamp. 
         [0049]    The end of the pole arm  14  is placed flush against the side  55  of the housing  40 . The clamp retaining bracket  63  and fastener  64  holds the stainless steel screw/band clamps  61  in place on pole arm to housing mounting arm  82  while the maintainer connects the wires to “I” shaped connector  45 , maneuvers the whole assembly into position and slides the housing  40  onto pole arm  14 . The fact that clamps  71  hold the assembly on pole arm  14  while the electrical connections are made is important, as the maintainers must typically wear thick rubber electrically insulating gloves while installing the luminaire. Once the electrical connections are made, the maintainer slides the housing  40  inward on pole arm  14  until the end of pole arm  14  contacts flush surface  55  and tightens the stainless steel screw/band clamps  61  to secure the entire assembly in place. 
         [0050]      FIG. 8  shows the same isometric view of the assembly as in  FIG. 7 , but shows the “I” connector  45  in better detail. Pole arm to housing mounting arm  82 , clamps  61 , clamp retaining bracket  63 , fastener  64 , and photocontrol  22  are removed for clarity.  FIG. 9  shows the fully assembled and installed luminaire  86 , with photocontrol  22  installed on housing  40 . Clamps  61  secure pole arm to housing mounting arm  82  to pole arm  14 . 
         [0051]      FIG. 10  shows a cross section view D-D (referring back to  FIG. 5E ) of the “I” connector  45 , according to one embodiment of the present invention. The main body  84  of the connector  45  is made of an insulating material such as such as plastic or ceramic. Two input terminals  65  &amp;  66  accept incoming power wires  59  &amp;  60  (not shown). An edge protrusion  68  keeps the sides of the inside of the metal pole arm from touching the wires and causing a short during installation. These are present on both sides of input terminals  65  &amp;  66  forming a distinctive “I” shape when seen on end, as in  FIG. 5E . Both input terminals  65  &amp;  66  have carrying conductors imbedded in the plastic or ceramic insulator body  84 . These conductors come out at the opposite (housing) end forming connection points  77  &amp;  78  for the wiring harness  72  (not shown) inside the housing  40 . The carrying conductors  74  &amp;  75  pass through a thickened portion of insulating body  84 , which shields the conductors from the housing. 
         [0052]    Screw terminal  65  is offset from screw terminal  66 . This accomplishes two things: first, it reduces the likelihood of a short, as a stripped wire will be drawn in further down the side of the connector lessening the chance that stray wires will flex around the center portion  69  of insulator  84  and touch the other wire, thus causing a short. Secondly, the offset conserves space, allowing small pole arms to comfortably fit over the connector. 
         [0053]    A mounting flange  76  on the end allows for attaching the entire connector  45  to the main housing  40  via threaded, riveted, or other fasteners  73  (shown in  FIG. 5E ) commonly known in the art. 
         [0054]      FIGS. 11A and 11B  show side and front views, respectively, of the “I” connector according to one embodiment of the present invention. 
         [0055]      FIGS. 12A and 12B  show side and front views, respectively, of a variation of connector  87  with the edge protrusions  1200  angled in towards input terminals  65  &amp;  66 . This configuration is referred to herein as a “back-to-back C-shape” arrangement of edge protrusions. 
         [0056]      FIGS. 13A and 13B  show side and front views, respectively, of a variation of connector  88  with edge protrusions  1300  that “box in” input terminals  65  &amp;  66 . The side view shows a hole  1310  placed over input terminal  66  so that the maintainer can access terminal screw  66  with a screwdriver. 
         [0057]    While the above descriptions represent a preferred embodiment of the present invention, it should be acknowledged that the invention may be modified in form and/or detail by those skilled in the art. Various other advantages of the present invention will become apparent to those skilled in the art after having the benefit of studying the foregoing text and drawings taken in conjunction with the appended claims. Accordingly, the appended claims encompass within their scope all such changes and modifications.