Abstract:
An access door unit includes a door, doorway structure, and elements for pivotally attaching the door to the doorway structure. The doorway structure has an outer perimeter frame and base affixed thereon. The base has support members extending in transverse relation to and outwardly fore and aft from the outer perimeter frame and adapted to rest on a generally level support surface such that the outer perimeter frame extends upright from the base enabling the doorway structure to assume a free-standing, self-supporting orientation on the support surface. The outer perimeter frame of the doorway structure defines a passage large enough to fit the door and permit entry or exit through the passage when the door is opened. A closure panel of the door may be full or half length in accordance with the different uses being made of the access door unit.

Description:
This patent application is a continuation-in-part of U.S. application Ser. No. 13/507,285 filed Jun. 19, 2012, which claims the benefit of U.S. Provisional Application No. 61/571,105 filed Jun. 21, 2011. The patent application also claims the benefit of U.S. Provisional Application No. 61/961,457 filed Oct. 15, 2013. Each application identified above is hereby incorporated by reference in its entirety to provide continuity of disclosure. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to access to enclosures, such as batting cages, and, more particularly, is concerned with access door unit. 
     2. Description of the Prior Art 
     Enclosures, for example batting cages, typically do not come with or have a conventional or regular style door, one that opens, closes, latches, and allows users with baseball equipment to entry and exit easily to and from the batting cage. There are some batting cages that have what is called a “flap door”, built into the net of the batting cage. The flap door typically is an overlapped piece of the net configured to form a flap that covers an opening in the netting. To enter or exit the batting cage the user has to fold back the flap and navigate through the opening usually while carrying baseball equipment. The flap door typically is cumbersome to manipulate and does not open wide enough for easy passage with equipment. Additionally, they are difficult to see and thus find in that they do not appear distinct from the net. Thus, they are neither easy nor convenient to use. 
     Many batting cages require users to lift a net wall of the batting cage to enter and exit. Lifting the cage wall can be difficult for many users in that a user has to stoup over or bend down. Furthermore, requiring that a wall be capable of being lifted for allowing entry or exit can also prevent the batting cage user from safely anchoring or “staking or weighting” the bottom edges of the batting cage walls to prevent passage of balls from the cage. 
     U.S. Patent No. Des. 276,466 to Giovagnoli discloses a batting cage with access doors to its batting compartments. The batting cage appears to be constructed by an extended framework supporting a net so as to define a plurality of side-by-side batting compartments. The extended framework appears to incorporate and support a doorway frame portion in a front wall of each batting compartment that extends from a corner thereof. The access doors to the batting compartments appear to be pivotally supported by the doorway frame portions. The approach of this design patent would appear to be dependent on and limited to the batting cages having the particular arrangement of the extended framework. 
     SUMMARY OF THE INVENTION 
     The present invention provides an access door unit designed to overcome the above-described drawbacks and satisfy the need for versatile, convenient and easy access to inside an enclosure, such as a batting cage. Specifically, the access door unit provides a doorway structure and a door which can be easily assembled and installed to provide the access door unit in a self-supporting relationship to the batting cage at any one of various different locations about the perimeter of the batting cage. The doorway structure has its own base support members which allow the unit to be self-standing, or free-standing, and thus installable in the self-supporting relationship at any of the different locations. Also, in one exemplary embodiment the door utilizes a double layer sock net which is easy to assemble on a peripheral door frame to form a closure panel of the door. 
     Accordingly, the present invention is directed to an access door unit which includes a door and a doorway structure. The door has a periphery and includes a peripheral frame defining the periphery and an interior open area of the door, and a closure panel attachable to the peripheral frame so as to extend across the interior open area of the peripheral frame. 
     The doorway structure has an outer perimeter frame and a support base. The outer perimeter frame includes right and left upright side portions and top and bottom portions extending between and interconnecting the right and left upright side portions so to define a passage through the outer perimeter frame being surrounded in continuous fashion by the outer perimeter frame and enough larger than the periphery of the door so that that door can fit within the passage of the doorway structure. 
     The support base is affixed on the outer perimeter frame. The support base includes right and left support members spaced apart from one another and extending in transverse relation to and outwardly in opposite fore and aft directions from the bottom portion of the outer perimeter frame such that the right and left support members are adapted to rest on a generally level support surface with the outer perimeter frame extending upright from the support base enabling the doorway structure, due solely to the right and left support members of the support base resting on the support surface, and solely to the outer perimeter frame extending upright from the support base, to assume a free-standing, self-supporting orientation on the support surface without any additional support from any other structure. 
     The access door unit also includes a plurality of elements for enabling the door to be pivotally moved toward and away from the passage of the outer perimeter frame of the doorway structure to permit entry or exit through the passage of the doorway structure. 
     In one embodiment, the closure panel of the door extends the full length of the interior open area of the peripheral frame of the door. In another embodiment, the closure panel of the door is a protective screen that extends approximately half of the length of the interior open area of the door and is pivotally convertible between up and down positions relative to the door and doorway structure in accordance with corresponding use for protecting softball and baseball pitchers. In further embodiment, the door is a protective screen that extends approximately half of the length of the passage of the doorway structure and is movably convertible between up and down positions relative to the doorway structure in accordance with corresponding use for protecting softball and baseball pitchers. 
     These and other features and advantages of the present invention will become apparent to those skilled in the art upon a reading of the following detailed description when taken in conjunction with the drawings wherein there is shown and described an illustrative embodiment of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the following detailed description, reference will be made to the attached drawings in which: 
         FIG. 1  is an elevational view of an exemplary embodiment of an access door unit installed in a batting cage in accordance with the present invention, showing a user initiating the opening of a door of the unit, the view also containing an enlarged fragmentary view to show the strands of a double layer sock net forming a closure panel of the door. 
         FIG. 2  is an elevational view similar to that of  FIG. 1 , now showing the user entering the batting cage through an access opening defined through a doorway structure of the unit after the door of the unit has been opened. 
         FIG. 3  is a perspective assembled view of an exemplary embodiment of the doorway structure of the access door unit which provides the unit with a self-standing, or free-standing, capability enabling it to be self-supporting relative to the batting cage. 
         FIG. 4  is a perspective disassembled view of doorway structure of  FIG. 4 . 
         FIGS. 5-11  are a succession of views illustrating an exemplary embodiment of a sequence of steps in a method of installing the assembled doorway structure  18  of  FIG. 3  in the net  12  of the batting cage  10 . 
         FIG. 12  is a perspective assembled view of an exemplary embodiment of a peripheral frame of the door of the access door unit. 
         FIG. 13  is a perspective disassembled view of the peripheral frame of the door of the unit. 
         FIGS. 14-16  are a succession of views of an exemplary embodiment of a sequence of steps in a method of installing the sock net over the assembled peripheral frame of the door of  FIG. 12 . 
         FIG. 17  is an elevational view of one exemplary embodiment of a hinge used to pivotally attach the door to the doorway structure of the access door unit. 
         FIG. 18  is an elevational view of another exemplary embodiment of a hinge used to pivotally attach the door to the doorway structure of the access door unit. 
         FIGS. 19-22  are respective perspective and elevational views of an exemplary embodiment of components of a latch mechanism used to latch the door to doorway structure of the access door unit. 
         FIG. 23  is a perspective view of a top door stop affixed to a top portion of the door of the access door unit. 
         FIG. 24  is a perspective view of a bottom door stop affixed to a bottom portion of the door of the access door unit. 
         FIG. 25  is an elevational view of another exemplary embodiment of an access door unit adapted for use as a protective screen for a softball pitcher. 
         FIG. 26  is an elevational view of the access door unit of  FIG. 25  now converted for use as a protective screen for a baseball pitcher. 
         FIG. 27  is a side elevational view of the access door unit showing converting of its protective screen between an “up” position for softball and a “down” position for baseball. 
         FIG. 28  is an elevational view of still another exemplary embodiment of an access door unit adapted for use as a protective screen for a softball pitcher. 
         FIG. 29  is an elevational view of the access door unit of  FIG. 28  now converted for use as a protective screen for a baseball pitcher. 
         FIG. 30  is an elevational view of the doorway structure of the unit of  FIGS. 28 and 29 . 
         FIG. 31  is an elevational view of the screen panel of the unit of  FIGS. 28 and 29 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings, and particularly to  FIGS. 1 and 2 , there is illustrated a wall of a conventional batting cage  10  formed by a vertically suspended or hanging net  12  unattached or free at its lower edge. (In various of the figures portions of the net  12  have been omitted for purposes of clarity and convenience in illustration.) The net  12  may be fabricated from strands of any suitable, preferably flexible, material, such as fabric, plastic or metallic woven cord or wire. Also shown is an exemplary embodiment of an access door unit  14 , which constitutes one aspect of the present invention, installed or built into the net  12  of the batting cage  10 . The access door unit  14  permits easy and convenient entry into and exit from the batting cage  10 , as shown in  FIGS. 1 and 2 . While the access door unit  14  is disclosed herein installed into the wall or net  12  of the batting cage  10 , it should be understood that the unit  14  also may be installed in a wall of a tent or various other types of enclosures. 
     As seen in  FIGS. 1 and 2 , the access door unit  14  basically includes a door  16 , and a stationary self-standing doorway structure  18  surrounding the door  16  (when the door  16  is closed) and pivotally supporting the door  16  by an outer perimeter frame  30  of the doorway structure  18  which also defines a passage  20  through the doorway structure  18 . The door  16  basically includes a peripheral frame  22  of generally rectangular configuration defining a periphery of the door  16 . The door  16  also includes a closure panel  24  attached to and extending across an interior open area  26  defined by the peripheral frame  22 . The doorway structure  18  basically includes a base  28  and the outer perimeter frame  30  of generally rectangular configuration attached on and extending upright from the base  28 . The outer perimeter frame  30  of the doorway structure  18  is enough larger in circumference than the peripheral frame  22  of the door  16  that the latter can fit within the passage  20  of the former. To enter or exit the batting cage  10  a user unlatches the door  16 , pivots the door  16  from a closed position to an opened position located away from the doorway structure  18 , and then walks through its passage  20 . The door  16  may then be returned to its closed position, either automatically or manually, and latched to the doorway structure  18  when it reaches the closed position. 
     More clearly,  FIGS. 3 and 4  show an exemplary embodiment of the doorway structure  18  that provides the access door unit  14  with a self-standing, self-supporting capability. This capability frees the access door unit  14  of the need for additional support from any structural frame component of the batting cage  10 . It also allows the unit  14  to be quickly and easily installed in association only with the net  12  of the batting cage  10 . With the access door unit  10  so installed self-standing on a substantially level flat surface  32 , which also supports the batting cage  10 , the net  12  of the batting cage  10  need not be disturbed. Instead, since entry and exit by users will now be through the passage  20  of the doorway structure  18  by use of the door  16 , the bottom of the net  12  may be permanently staked or anchored to the support surface  32  in order to prevent balls from escaping the confinement of the batting cage  10 . Furthermore, the access door unit  14  may be installed either in a new or (retrofitted in) an existing batting cage used either indoors or outdoors. 
       FIGS. 3 and 4  show the doorway structure  18  of the access door unit  14  by itself. (It should be noted here that the orientation of the doorway structure  18  shown in  FIG. 3  is the reverse of that shown in  FIGS. 1 and 2 . It should be further noted that parts of the doorway structure  18  hereinafter identified as “right” and “left” are labeled in reference to their orientation in the doorway structure  18  as shown in  FIGS. 3 and 5-11 , and not as shown in  FIGS. 1 and 2 .) The doorway structure  18  may be assembled from a plurality  34  of parts, for example, four pairs of parts or eight parts in total, into the base  28  and an outer perimeter frame  30 . The plurality  34  of parts may be constructed from widely-available metal tubing, for example steel or aluminum, by using well-known fabrication techniques. The plurality  34  of parts may be marketed disassembled in a package and then fitted and assembled, at the site of the batting cage  10 , to one another, for example, at mateable male and female ends. The assembled parts are then secured together by use of fasteners, such as bolts and nuts (which are included in the disassembled parts package), applied to the mated ends in preparation for installing the doorway structure  18  into the net  12  of the hitting cage  10 . In an exemplary embodiment, the doorway structure parts of each pair may be substantially identical to one another but different from the doorway structure parts of the other pairs. 
     In the exemplary embodiment shown in  FIG. 4 , the plurality  34  of parts for assembling the doorway structure  18  may include:
         (1) lower right and left leg parts  34 A,  34 B arranged in a mirror image relationship to one another, both having respective fore-and-aft extending legs  34 A- 1 ,  34 B- 1 , horizontal posts  34 A- 2 ,  34 B- 2  and vertical posts  34 A- 3 ,  34 B- 3  such that the horizontal and vertical posts are rigidly affixed on each of the respective legs at approximately midway between the opposite ends of the legs;   (2) upper right and left corner parts  34 C,  34 D also arranged in a mirror image relationship to one another and each having a substantially right angle configuration;   (3) right and left side parts  34 E,  34 F of substantially straight configurations and disposed between and interconnecting corresponding upper right and left corner parts  34 C,  34 D with the respective vertical posts  34 A- 3 ,  34 B- 3  of the lower right and left leg parts  34 A,  34 B; and   (4) top and bottom parts  34 G,  34 H of substantially straight configurations, the top part  34 G disposed between and interconnecting the upper right and left corner parts  34 C,  34 D with one another, the bottom part  34 H disposed between and interconnecting the respective horizontal posts  34 A- 2 ,  34 B- 2  of the lower right and left leg parts  34 A,  34 B with one another.
 
The fore-and-aft extending leg  34 A- 1 ,  34 B- 1  and horizontal posts  34 A- 2 ,  34 B- 2  of the lower right and left leg parts  34 A,  34 B in conjunction with the bottom part  34 H, which interconnects the horizontal posts  34 A- 2 ,  34 B- 2 , constitute the base  28  of the doorway structure  18 . The upper right and left corner parts  34 C,  34 D, the vertical and horizontal posts  34 A- 3 ,  34 B- 3  and  34 A- 2 ,  34 B- 2  of the lower right and left leg parts  34 A,  34 B and the bottom part  34 H, which interconnects the horizontal posts  34 A- 2 ,  34 B- 2 , constitute the outer perimeter frame  30  of the doorway structure  18 . In addition, upper and lower hinges  36 A,  36 B are included in the disassembled parts package already attached to the upper left corner part  34 D and left side part  34 F of the doorway structure  18 . The hinges  36 A,  36 B per se may be widely-available self-closing spring door types. The hinges  36 A,  36 B as shown in  FIGS. 3 and 17  and hinges  60 ,  62 , as shown in  FIG. 18 , are examples of suitable hinges that can be used. A door latch receiver  38  is also included in the disassembled parts package already attached to the right side part  34 E approximately midway along the right vertical side  18 A of the doorway structure  18 .
       

       FIGS. 5-11  show an exemplary embodiment of a sequence of steps in a method of installing the assembled doorway structure  18  in the net  12  of the batting cage  10 , which method constitutes another aspect of the present invention.  FIG. 5  shows the doorway structure  18  placed adjacent the net  12  in the desired location where the access door unit  14  will be installed.  FIGS. 6 and 7  show an initial sequence of steps taken to cut a generally centrally-located, vertically-elongated, rectangular-shaped hole  40  into a portion of the net  12  located within the outer perimeter frame  30  of the doorway structure  18 . This is done in order to start to open the net  12  to provide the doorway passage  20  through it.  FIGS. 7-9  show right, left and top marginal portions  12 A- 12 C of the net  12  left untrimmed to allow their subsequent attachment respectively along the right vertical side  18 A, left vertical side  18 B and horizontal top  18 C of the doorway structure  18 . The horizontal bottom  18 D of the doorway structure  18  which bounds the bottom of the passage  20  is, of course, left unattached to the net  12 .  FIG. 8  shows slits  42  cut in the net  12  at approximately diagonal angles that intersect upper right and left corners  18 E,  18 F of the outer perimeter frame  30 . The slits  42  facilitate folding the right, left and top marginal portions  12 A- 12 C of the net  12  over and about the right and left vertical sides  18 A,  18 B and horizontal top  18 C of the doorway structure  18  and then attaching the marginal portions  12 A- 12 C to portions of the net, in a final sequence of steps shown in  FIGS. 9 and 10 . The attaching step involves lacing or securing the marginal portions  12 A- 12 C of the net  12  to the adjacent portions around the exterior of the outer perimeter frame  30  using strands  44  of flexible string, core or rope of appropriate lengths.  FIG. 11  shows the completed installation of the doorway structure  18  in a freestanding orientation after the cage net  12  has been secured to the right and left vertical sides  18 A,  18 B and horizontal top  18 C of the doorway structure  18 . 
       FIGS. 12 and 13  show the peripheral frame  22  of the door  16  of the access door unit  14  by itself. (It should be noted here that the orientation of the door  16  shown in  FIGS. 12 and 14-16  is the same of that shown in  FIGS. 1 and 2 ). The peripheral frame  22  of the door  16  may be assembled from a plurality  46  of parts, for example, four pairs of parts or eight parts in total, into the peripheral frame  22 . The plurality  46  of parts may be constructed from widely-available metal tubing, for example steel or aluminum, by using well-known fabrication techniques. The plurality  46  of parts may be marketed disassembled in a package and then fitted and assembled to one another, for example, at mateable male and female ends. The assembled parts are then secured together by use of fasteners, such as bolts and nuts (which are included in the disassembled parts package), applied to the mated ends. The closure panel  24  of the door  16  attached to and extending across the interior open area  26  defined by the peripheral frame  22  may be constituted, for example, by a double layer of netting (see  FIG. 1 ) formed into a sock net  48  (which also is included in the disassembled parts package). It is combined with the assembled parts of the peripheral frame  22  by sliding it over the assembled parts so that the sock net  48  extends across and covers the interior open area  26  bounded by the assembled parts of the peripheral frame  22 , before mounting the door  16  to the doorway structure  18  via the upper and lower hinges  36 A,  36 B shown in  FIG. 3 . An alternative to the sock net  48  is a single layer of netting to form the closure panel  24  which could be employed by lacing the single layer of netting onto the peripheral frame  22  of the door  16 . The use of the sock net  48 , however, provides added convenience and is more durable in its ability of absorb impacts from balls. In an exemplary embodiment, the door parts of each pair may be substantially identical to one another but different from the door parts of the other pairs. 
     In the exemplary embodiment shown in  FIG. 13 , the plurality  46  of parts for assembling the peripheral frame  22  of the door  16  may include:
         (1) lower right and left corners parts  46 A,  46 B arranged in a mirror image relationship to one another and each having a substantially right angle configuration;   (2) upper right and left corner parts  46 C,  46 D also arranged in a mirror image relationship to one another and each having a substantially right angle configuration;   (3) right and left side parts  46 E,  46 F of substantially straight configurations disposed between and interconnecting corresponding upper right and left corner parts  46 C,  46 D with lower right and left corner parts  46 A,  46 B; and   (4) top and bottom parts  46 G,  46 H of substantially straight configurations and disposed between and interconnecting corresponding upper right and left corner parts  46 C,  46 D with one another and lower right and left corner parts  46 A,  46 B with one another.
 
In addition, a pivotal door latch  50  seen in  FIG. 12  is included in the disassembled parts package already pivotally attached to the left side part  46 F. The location of the door latch  50  is approximately midway along the midway along the left vertical side  16 C of the door  16 .
       

       FIGS. 14-16  show an exemplary embodiment of a sequence of steps in a method of installing the sock net  48  over the assembled door  16 , which method constitutes yet another aspect of the present invention.  FIG. 14  shows the sock net  48  closed at what will become it top end  48 A and opened at what will become its bottom end  48 B after it is applied to the door  16  as shown in  FIG. 1 .  FIGS. 15 and 16  show the sock net  48  at its open bottom end  48 B placed over the horizontal top  16 A of the door  16  and slid down the right and left vertical sides  16 B,  16 C of the door  16  until the sock net  48  fully covers the interior open area  26  (see  FIG. 12 ) bounded by the door  16 .  FIG. 1  shows the door  16  installed in the doorway structure  18  after the sock net  48  has been applied and the bottom end  48 B of the sock net  48  tied in place to the bottom  16 D of the door  16 . 
     As shown in  FIG. 1 , the door  16  is attached to the doorway structure  18  via the upper and lower hinges  36 A,  36 B, which are better seen  FIGS. 3 and 17 . Also,  FIG. 17  shows close-up details of the hinge  36 A,  36 B pivotally attaching the door  16  to the doorway structure  18 .  FIGS. 12 and 3  respectively show one exemplary embodiment of components of a latch mechanism having the pivotal door latch  50  on the door  16  and the latch receiver  38  on the doorway structure  18 . As the door  16  is moved to within the passage  20  of the doorway structure  18  the latch  50  rides up a ramp defined on the receiver  38  until it reaches an upwardly open notch. The latch  50  rotates and drops into the notch such that the door  16  is now latched in the closed position. By the user standing at the outside of the door  16  as shown in  FIG. 1 , after lifting the latch  50  from the notch the user can then pull on the door  16  to swing it open. A tab may be affixed to the door  16  so as to protrude from below the latch  50  and hold or supports the latch  50  in a horizontal position in which it will engage the ramp and ride up the ramp and fall into the notch merely by the closing movement of the door which is automatically caused by the self-closing hinges  36 A,  36 B. This capability ensures that the door  16  closes after each use. The user standing at the inside of the door  16  can reach a finger through the net  12  and engage and lift the latch  50  from receiver  38  in order to push open the door  16 . 
       FIGS. 19-22  show another embodiment of components of a latch mechanism having double latches  54  and double receivers  56  which can be used on the door  16  and doorway structure  18 . The double latches  54  are pivotally mounted at the front and rear (or outside and inside) of the right vertical side  16 B of the door  16 . The arms  58  may be separate from one another so as to be pivotally movable independently of one another or may be connected together so as to be pivotally movable in unison or together. In either case, they move toward and away from the double receivers  56  which are affixed at front and rear (or outside and inside) of the right vertical side  18 A of the doorway structure  18 . 
       FIG. 18  shows one hinge of a pair thereof of a different type (than that of  FIG. 17 ), which can be used to pivotally mount the door  16  to the doorway structure  18 , replacing the upper and lower hinges  36 A,  36 B seen in both  FIGS. 3 and 17 . Each hinge includes an upper tubular part  60  affixed to the door  16 , a lower tubular part  62  affixed to the doorway structure  18 , and a hinge pin  64  which inserts from above downward first through the upper tubular piece  60  and then through the lower tubular piece  62 . 
       FIGS. 23 and 24  show top and bottom door stops  66 ,  68  affixed to the top  16 A and bottom  16 B of the door  16 . The top and bottom door stops  66 ,  68  may take the form of straight parts which respectively extend upwardly from the top  16 A and downwardly from the bottom  16 D of the door  16  through sufficient distances to respectively engage the top  18 C and bottom  18 D of the doorway structure  18  so as to prevent the door  16  from swinging through the doorway structure  18  and instead restrict its pivotal movement toward and away from the doorway structure  18  to either at the front or rear of the doorway structure  18 , depending upon whether the door stops  66 ,  68  are affixed to the front or rear of the door  16 . 
     Referring now to  FIGS. 25-27 , there is illustrated another exemplary embodiment of an access door unit, generally designated  70  adapted for free-standing use as a protective screen structure for a softball pitcher.  FIGS. 25 and 26  show the door unit  70  having a doorway structure  72  and a door  74 , as described hereinbefore with respect to door unit  14  except that the door  74  has a closure panel in the form of a protective screen  76  that extends about half the length of the interior open area  80  of the door  74  and thus of the passage of the doorway structure  72 . The protective screen  76  is mounted to a transverse shaft  78  which extend across the interior open area  80  of the door  74  and is attached to right and left upright side portions  82 ,  84  of the outer peripheral frame  86  of the door  74  about midway between the top and bottom thereof. In such manner, the protective screen  76  is mounted to be pivotally converted, as shown in  FIG. 27 , between an upper position shown in  FIG. 25  and a lower position shown in  FIG. 26 . In the upper or “up” position of  FIG. 25  the protective screen is deployed for screening the upper portion of the interior open area  80  and thereby protecting a softball pitcher who will deliver the softball through the lower open portion  88  of the interior open area  80  of the door  74 . In the lower or “down” position of  FIG. 26  the protective screen is deployed for screening the lower portion of the interior open area  80  and thereby protecting a baseball pitcher who will deliver the baseball through the upper open portion  89  of the interior open area  80  of the door  74 . 
     Referring to  FIGS. 28-31 , there is illustrated still another exemplary embodiment of an access door unit, generally designated  90 .  FIGS. 28 and 29  show the door unit  90  having a doorway structure  92  and a door  94 . The doorway structure  92  is as described hereinbefore with respect to door unit  14 . The door  94  and its closure panel in the form of a protective screen  95  is now about half the length of the passage  96  of the doorway structure  92 , instead of the full length as in the case of door units  14  and  70 , so as to adapt the door  94  for use as a protective screen for a softball pitcher throwing the softball underhand when in the “up” position of  FIG. 28  and for a baseball pitcher throwing the baseball overhand when in the “down” position of  FIG. 29 .  FIGS. 30 and 31  respectively show the doorway structure  92  and door  94  of the door unit  90  of  FIGS. 28 and 29  with the sets of spaced apart hinges  98 A,  98 B and  100  and latches  102 A,  102 B and  104  on the outer perimeter frame  106  of the doorway structure  92  and the peripheral frame  108  of the door  94 . To convert the door  94  between the “up” position of  FIG. 29  and the “down” position of  FIG. 29 , it may be lifted off one set of the hinges  98 A,  98 B on the doorway structure  92  and dropped onto the other set of hinges  98 A,  98 B on the doorway structure  92 . On either set of hinges of the doorway structure  92 , the door  94  is pivotally supported by the doorway structure  92  so as to be pivotally movable between a closed condition, wherein the door  94  is secured to the doorway structure  92  by either of latches  102 A and  102 B on the doorway structure  92  and the latch  104  on the door  94 , and an opened condition, permitting entry or exit through the passage of the doorway structure  92 . 
     To summarize, the above-described access door unit  14  is a self-supporting and self-standing door assembly that allows a buyer to quickly and easily install the unit in the net wall or end of the batting cage  10 . The unit  14  may be advantageously marketed as a disassembled kit with conventional metal components or hardware to assemble the door  16  and doorway structure  18  and also with the netting for providing the sock net  48  to form the closure  24  of the door  16 . The unit  14  gives the consumer the option to buy, assemble and install the unit into an existing batting cage  10 . Thus, the unit  14  can be retrofitted to existing batting cages as well as installed with new batting cages. Also, the unit  14  can be used on indoor or outdoor batting cages. The unit  14  needs to be installed on a flat level indoor or outdoor surface so that the unit can stand alone without tilting or tipping over. Also, the access door units  70 ,  90  are self-supporting and self-standing and may be advantageously marketed as a disassembled kit in the same fashion as the access door unit  14 . 
     It is thought that the present invention and its advantages will be understood from the foregoing description and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the forms hereinbefore described being merely exemplary embodiments thereof.