Abstract:
A trailer security system for a utility trailer is disclosed. The trailer security system includes a pair of side detection units and a middle detection unit provided between the side detection units which are placed in the utility trailer. Upon entry of an intruder into the utility trailer, at least one of the detection units is activated, thus scaring the intruder and alerting persons in the vicinity of the trailer to the presence of the intruder. A method of securing a utility trailer against intrusion is also disclosed.

Description:
FIELD OF THE INVENTION 
   The present invention relates to security systems. More particularly, the present invention relates to a trailer security system which alerts to the presence of an intruder breaking into a utility trailer. 
   BACKGROUND OF THE INVENTION 
   Utility trailers are commonly used by sportsmen to store and transport expensive sports equipment as well as by contractors, tradesmen and construction workers to store and transport tools, construction supplies and other items. Such utility trailers typically include a wheeled frame on which is mounted a housing having a housing interior for storage of the items and a door which can be locked to secure the items in the housing interior. However, utility trailers typically lack an alarm system for alerting persons to the presence of intruders breaking into the trailer. 
   Therefore, a trailer security system is needed for alerting persons to the presence of an intruder or intruders breaking into a utility trailer. 
   SUMMARY OF THE INVENTION 
   The present invention is generally directed to a trailer security system for a utility trailer. The trailer security system includes a pair of side detection units and a middle detection unit provided between the side detection units which are placed in the utility trailer. Upon entry of an intruder into the utility trailer, at least one of the detection units is activated, thus scaring the intruder and alerting persons in the vicinity of the trailer to the presence of the intruder. The invention is further directed to a method of securing a utility trailer against intrusion. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described, by way of example, with reference to the accompanying drawings, in which: 
       FIG. 1  is a top view of a trailer, with the trailer security system of the present invention mounted in the trailer; 
       FIG. 2  is a perspective view of a remote control unit which is suitable for activating and inactivating the trailer security system; 
       FIG. 3  is a front perspective view of a transmitter component of the trailer security system, taken along section line  3  in  FIG. 1  and mounted on the trailer housing; 
       FIG. 4  is a side view of the transmitter, with a light beam being emitted from the transmitter; 
       FIG. 5  is a front perspective view of a receiver component of the trailer security system, taken along section line  5  in  FIG. 1 ; and 
       FIG. 6  is a side view of the receiver, with a light beam emitted by the transmitter being received by the receiver. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to the drawings, an illustrative embodiment of the trailer security system of the present invention is generally indicated by reference numeral  1  in  FIG. 1 . The trailer security system  1  is adapted for use in a utility trailer  36 , which may be conventional and includes a trailer housing  37 , typically mounted on a wheeled frame (not shown). The trailer housing  37  has a pair of side walls  37   a , a front wall  37   b , a rear wall  37   c , a floor  37   d  and a ceiling (not shown) which is supported by the side walls  37   a , front wall  37   b  and rear wall  37   c . A housing interior  38  which is selectively closed by one or a pair of doors (not shown) that is provided on the trailer housing  37  and can be selectively locked, using a padlock (not shown) or other locking mechanism, typically in conventional fashion. As will be hereinafter further described, the trailer security system  1  is mounted in the housing interior  38  to sense the presence of intruders breaking into the trailer housing  37  and alert bystanders or other persons to the presence of the break-in. 
   The trailer security system  1  includes a pair of side detection units  2  which are provided in the housing interior  38 , on respective sides of the trailer housing  37 , and a middle detector unit  3  which is provided in the housing interior  38 , in the middle of the trailer housing  37 . Each of the side detector units  2  includes a transmitter  6  which is mounted on the rear wall  37   c  or corresponding side wall  37   a  of the trailer housing  37  and a receiver  16  which is mounted on the front wall  37   b  or corresponding side wall  37   a  of the trailer housing  37 . The receiver  16  is positioned in receiving relationship with respect to light emitted from the corresponding transmitter  6  of each side detector unit  2 , as will be hereinafter described. The middle detector unit  3  also includes a transmitter  6  which is typically attached to or suspended from the ceiling (not shown) of the trailer housing  37  and a receiver  16  which is typically attached to or suspended from the ceiling or attached to the front wall  37   b  of the trailer housing  37 . The receiver  16  is positioned in receiving relationship with respect to light emitted from the transmitter  6  of the middle detector unit  3 , as will be hereinafter described. 
   As shown in  FIGS. 3 and 4 , the transmitter  6  of each side detector unit  2  and the middle detector unit  3  typically includes a transmitter housing  7  which is attached to the trailer housing  37  using hook-and-loop fastener strips  8 , magnets (not shown), threaded fasteners (not shown) or other suitable technique known to those skilled in the art. A transmitter microprocessor (not shown) is provided in the transmitter housing  7 . The transmitter microprocessor is connected to a battery (not shown) provided in a battery compartment  9  which is contained in the transmitter housing  7 . An audible alarm  10  may be provided on the transmitter housing  7  and connected to the transmitter microprocessor. A receiver  11  may be provided on the transmitter housing  7  and connected to the transmitter microprocessor to facilitate activation of the transmitter  6  from an “off” mode to an “on” mode, and vice-versa, using a hand-held remote control device  26  ( FIG. 2 ), as will be hereinafter described. Alternatively or additionally, a power switch (not shown) may be provided on the transmitter housing  7  and connected to the transmitter microprocessor to facilitate manual activation or inactivation of the transmitter  6 . A lens housing  12 , in which is mounted a translucent lens  13 , is further provided on the transmitter housing  7 . A light-emitting device (not shown) is provided in the transmitter housing  7  and connected to the transmitter microprocessor. The light-emitting device is suitably positioned to transmit light from the transmitter housing  7 , through the lens  13  when the transmitter  6  is in the “on” mode. The transmitter microprocessor in the transmitter housing  7  includes the capability of being activated to the “on” mode by the remote control device  26  through the receiver  11  and energizing the light-emitting device (not shown) to emit a light beam  14  from the transmitter housing  7 , through the lens  13 , as shown in  FIG. 4 , as long as the transmitter  6  remains in the “on” mode. 
   As shown in  FIGS. 5 and 6 , the receiver  16  of each side detector unit  2  and the middle detector unit  3  typically includes a receiver housing  17  which is attached to the trailer housing  37  using hook-and-loop fastener strips  18 , magnets (not shown) or other suitable technique known to those skilled in the art. A receiver microprocessor (not shown) is provided in the receiver housing  17 . The receiver microprocessor is connected to a battery (not shown) provided in a battery compartment  19  which is contained in the receiver housing  17 . An audible alarm  20  may be provided on the transmitter housing  7  and connected to the receiver microprocessor. A receiver  21  may be provided on the receiver housing  17  and connected to the receiver microprocessor to facilitate activation of the receiver  16  to the “on” mode using the hand-held remote control device  26  ( FIG. 2 ), as will be hereinafter described. A power switch (not shown) may be additionally or alternatively provided on the receiver housing  17  and connected to the receiver microprocessor to facilitate manual activation or inactivation of the receiver  16 . A lens opening  22 , in which is mounted a translucent lens  23 , is further provided on the receiver housing  17 . A light sensor (not shown) is provided in the receiver housing  17  and connected to the receiver microprocessor. The light sensor is suitably positioned to continually receive light from the transmitter  6  as long as the transmitter  6  remains in the “on” mode. The receiver microprocessor in the receiver housing  17  includes the capability of being activated by the remote control device  26  through the receiver  21  and energizing the light sensor (not shown) to receive the light beam  14  from the transmitter  6 , as shown in  FIG. 6 . The receiver microprocessor further includes the capability of activating the alarm  20  in the event that the light sensor stops receiving the light beam  14  through the lens  23  at any time while the receiver  16  is in the “on” mode. 
   As shown in  FIG. 2 , the remote control device  26  typically includes a housing  27  which houses a remote control microprocessor (not shown). A battery compartment (not shown) is provided in the housing  27  and contains a battery (not shown) which is connected to the remote control processor. A transmitter  32  is provided on the housing  27  and is connected to the remote control microprocessor. An “on” button  28 , an “off” button  29 , an alarm  30  and a lighting device  31  are further provided on the housing  27 , and each is connected to the remote control microprocessor. Accordingly, upon depression of the “on” button  28 , the remote control microprocessor transmits a signal which is received by the receiver  11  of the transmitter  6  ( FIG. 3 ) and the receiver  21  of the receiver  16  ( FIG. 5 ) of both of the side detector units  2  and the middle detector unit  3  to activate each transmitter  6  and receiver  21 . The lighting device  31  is illuminated to indicate the “on” status of the trailer security system  1 . Upon depression of the “off” button  29 , the remote control microprocessor transmits a signal which is received by the receiver  11  of the transmitter  6  and the receiver  21  of the receiver  16  of the side detector units  2  and the middle detector unit  3  to inactivate each transmitter  6  and receiver  21 . 
   As shown in  FIG. 1 , in typical use of the trailer security system  1 , the transmitter  6  and receiver  16  of each side detector unit  2  and the middle detector unit  3  is activated typically by depression of the “on” button  28  which is provided on the remote control device  26 . Accordingly, the transmitter  32  ( FIG. 2 ) on the remote control device  26  transmits a signal to the receiver  11  of each transmitter  6  and the receiver  21  of each receiver  16 . Therefore, each transmitter  6  emits a light beam  14  which is received by the receiver  16  of each side detector unit  2  and middle detector unit  3 . As long as the receiver  16  receives the light beam  14  from the corresponding transmitter  6 , the alarm  20  of each receiver  16  remains in an inactivated state. Accordingly, as shown in  FIG. 1 , each side and the middle front area of the housing interior  38  is constantly monitored for the presence of an intruder. 
   In the event that an intruder (not shown) breaks into the utility trailer  36 , the intruder interrupts the light beam  14  which is emitted by a transmitter  6  and received by the corresponding receiver  16  of one of the side detector units  2  or the middle detector unit  3 . Accordingly, the light sensor (not shown) provided in the receiver  16  transmits a signal to the receiver microprocessor (not shown) provided in the receiver  16 . In turn, the receiver microprocessor activates the audible alarm  20 , which emits an alarm sound. Therefore, the emitted sound attracts attention to the utility trailer  36  and scares off the intruder or intruders as well as alerts persons in the vicinity of the utility trailer  36  to the presence of an intruder or intruders breaking into the utility trailer  36 . 
   While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications can be made in the invention and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention.