Abstract:
A cargo truck ramp load assist system comprises a hand truck engagement device disposed in a longitudinal slot in a cargo truck ramp, a first actuator coupled to the hook operable to effect displacement of the hand truck engagement device along the longitudinal slot in the ramp, a remote controller coupled to a hand truck and equipped with a first radio transceiver, a second radio transceiver coupled to the first actuator operable to receive directional/speed control signals from the remote controller, and the hand truck engagement device operable to engage the hand truck and the first actuator effecting displacement of the hand truck engagement device up and down the ramp in response to the directional/speed control signals to facilitate the hand truck going up and down the ramp.

Description:
RELATED APPLICATION 
     This patent application claims the benefit of U.S. Provisional Patent Application No. 61/763,711 filed on Feb. 12, 2013. 
    
    
     FIELD 
     This disclosure relates to cargo trucks, and is related in particular to a radio-controlled cargo truck ramp load assist system and method. 
     BACKGROUND 
     Cargo trucks such as box trucks and semi-trailer trucks are the primary way of distributing and moving goods across land. The trucking industry provides an essential service to the American economy by transporting large quantities of raw materials, parts, and finished goods from manufacturing plants to wholesalers, distribution centers, and retail stores. Trucks are responsible for the majority of freight movement over land, and are vital components in the manufacturing, transportation, and warehousing industries. 
     In most cargo trucks, the floor of the cargo space is typically several feet above ground level. When loading or unloading goods using a hand truck or dolly, a ramp is often used to bridge the gap in elevation. However, for heavy or bulky loads, it is often a challenge to wheel the hand truck up and down the ramp in a safe manner. For example, due to the weight or bulk of the cargo, the hand truck may easy become out of control or gain speed down the ramp. Injury to the operator and damage to the cargo may result. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an exemplary embodiment of the load assist system according to the teachings of the present disclosure; 
         FIG. 2  is a more detailed perspective view of an exemplary embodiment of the load assist system according to the teachings of the present disclosure; 
         FIG. 3  is a more detailed view of an exemplary embodiment of a user interface and visual indicator device of the load assist system according to the teachings of the present disclosure; 
         FIG. 4  is a more detailed view of an exemplary embodiment of a hand truck controller of the load assist system according to the teachings of the present disclosure; and 
         FIG. 5  is a simplified block diagram of an exemplary embodiment of the load assist system according to the teachings of the present disclosure. 
     
    
    
     SUMMARY 
     A cargo truck ramp load assist system comprises a hand truck engagement device disposed in a longitudinal slot in a cargo truck ramp, a first actuator coupled to the hook operable to effect displacement of the hand truck engagement device along the longitudinal slot in the ramp, a remote controller coupled to a hand truck and equipped with a first radio transceiver, a second radio transceiver coupled to the first actuator operable to receive directional/speed control signals from the remote controller, and the hand truck engagement device operable to engage the hand truck and the first actuator effecting displacement of the hand truck engagement device up and down the ramp in response to the directional/speed control signals to facilitate the hand truck going up and down the ramp. 
     A cargo truck ramp load assist system comprises a hook disposed in a longitudinal slot in a cargo truck ramp, a first actuator coupled to the hook operable to effect displacement of the hook along the longitudinal slot in the ramp, a second actuator coupled to the hook operable to effect raised and lowered positions of the hook, a user interface configured to receive control input from an operator, a remote controller coupled to a hand truck and equipped with a first radio transceiver, the first radio transceiver configured to transmit the control input from the operator, a second radio transceiver coupled to the first actuator operable to receive the control input from the remote controller, and the hook operable to engage the hand truck and the first actuator effecting displacement of the hook up and down the ramp and the second actuator effecting raised and lowered positions in response to the control input to facilitate the operation of hand truck going up and down the ramp. 
     A remote-controlled cargo truck ramp loading method comprises elevating a hook disposed in a longitudinal slot in the cargo truck ramp, engaging a hand truck carrying a load with the hook, facilitating the hand truck going up or down the ramp via remote controlling the displacement of the hook along the longitudinal slot, and lowering the hook. 
     DESCRIPTION 
     Referring to  FIGS. 1 and 2 , a cargo vehicle  10  is a vehicle with a primary function of hauling goods and freight on roadways and highways, such as a box truck or a tractor trailer. Cargo vehicle  10  includes cargo space that is elevated several feet above ground level. A load assist system  16  incorporated in the hand truck  12  and ramp  14  is used to help load and unload goods into and out from the cargo space in a manner that avoids injury to the operator and damage to the goods being transported. 
     The ramp  14  is an elongated segment of platform that is used to enable an operator to push a hand truck  12  up the ramp into the cargo space or unload goods from the cargo space. The ramp  14  may be constructed of a strong and light-weight metal or metal composite including aluminum. The hand truck  12  and ramp  14  are equipped with a load assist system  16  that is operable to provide assistance to move the hand truck up or down the ramp  14  being controlled by the operator. The ramp  14  is equipped with a hook, protruding member, or engagement device  38  that may temporarily engage the hand truck  12 . 
     Referring also to  FIGS. 3-5 , the load assist system  16  includes controller circuitry  18  disposed on the hand truck  12  that communicates wirelessly with ramp load assist circuitry  20  disposed on the ramp and enables an operator to control its operations. The hand truck controller  18  includes a microprocessor or microcontroller  22  specially configured to receive input from the operator via a user interface  24  to control the operations of the load assist system  16 . For example, the user interface  24  may include up and down buttons  26  to control a motor  28  in the ramp load assist circuitry  20  that moves a cable or chain  30  disposed under the top surface of the ramp  14  to control the direction of travel up or down the ramp. The motor  28  may be any suitable electric/hydraulic/air-control motor with variable speed and direction capabilities. The user interface  24  may further include a speed control input, such as a thumb wheel  32  to control the motor speed which in turns sets the travel speed of the cable/chain  30 . A number of pre-set speed settings such as slow, medium, and fast may be provided. 
     Another user input device may include a button  34  that is used to control a solenoid  36  disposed in the ramp  14  that is coupled to a hook or protrusion  38  disposed in the ramp  14  and coupled to the motor  28  that can be raised to engage and lowered to disengage the hand truck  12  on the ramp. The user interface  24  is preferably integrated with or otherwise securely fastened to the handle bar or frame of the hand truck  12 . The hand truck controller  18  is preferably designed and positioned so that the operator may easily operate the controls of the user interface  24  while still able to safely and comfortably push and pull the hand truck. 
     The hand truck controller  18  may further include a visual indicator  40  to provide a visual indication of the system operation status. For example, multi-colored LEDs (light emitting diodes) may be used to indicate that the system is on/off and whether it is in a ready status. Further, an indicator (LED) may be used to indicate whether the hook  38  is in its raised or lowered position. The up and down buttons  26  may also be lit or dimmed to visually reflect the current directional status of the ramp load assist assembly  20 . The visual indicator  40  is especially useful when transporting bulky loads that may block the operator&#39;s view of the ramp. 
     The hand truck controller  18  communicates the operator commands to the ramp load assist assembly  20  via a wireless communication link between the respective transceivers and antennae  40  and  42 . The wireless communication link preferably uses radio frequency in accordance with suitable protocols to transmit signals between the hand truck controller  18  and the ramp load assist assembly  20 . Other modes of wireless communication now known or developed in the future that use other transmission media such as light, sound, electromagnetic fields may be used. The commands received by the wireless transceiver  42  in the ramp load assist assembly  20  is passed on to the controller  44 , which in turn interprets the commands and sends instructions to the solenoid  36  to control the hook operations and the motor  28  to control the direction of the hook movement along the ramp. 
     Referring particularly to  FIG. 2 , the ramp  14  preferably incorporates a longitudinal slot  46  disposed in or near the center of the ramp  14 . The ramp load assist assembly  20  enables the hook  38  to be raised through the longitudinal slot  46  and engage a bottom component of the hand truck  14  such as the axle or a slot in the bottom load-carrying platform. The hook  38  can be lowered when not in use to avoid a tripping hazard. The ramp load assist assembly  20  incorporates an actuation system such as a winch/rack and pinion/cable/pulley system or a bidirectional motor  28  that is operable to displace the hook  38  up and down the ramp  14 . Preferably, the ramp load assist assembly  20  and the hook  36  are housed in a sturdy and weatherproof enclosure  48  that is operable to travel along the ramp along the cable or chain and pulley system. 
     To load the vehicle with cargo, the hand truck  12  is positioned near the lower end of the ramp  14  and the operator instructs the system to raise the hook  38  via the user interface  24 . When extended, the hook  38  engages the hand truck  12 , and the operator can control the speed, again via the user interface  24 , that the hook  28  travels up the ramp, assisting in lifting the heavy load on the hand truck  12 . At the top of the ramp, the operator lowers the hook  38  or the hook is lowered automatically, and the hand truck  12  can easily be wheeled into the cargo box to unload the goods. The hand truck user interface  24  is preferably positioned so the operators do not have to take their hand off the power handle to operate the controls. 
     Although not shown, storage space beneath the floor of the cargo hold may accommodate the ramp  14  when the ramp is not in use. In this manner, the ramp  14  may be pulled out from the storage space and placed into position when it is needed, and put away into the space and out of the way when not needed. 
     Although not described in detail, the hand truck controller  18  and the ramp load assist assembly  20  include suitable power supplies such as batteries to power the electronic and electrical components. Alternatively, the ramp load assist  20  may draw power from the battery of the cargo vehicle. 
     The specific configuration of the hook or engagement device and the component on the hand truck that is engaged is preferably designed according to the design and construction of the hand truck. For example, the axle of the hand truck may be a convenient location to engage the hook. Alternatively, the nose plate that carries the load on the hand truck may incorporate an opening that enables the hook engagement. 
     Accordingly, personnel unloading or loading the cargo truck using a hand truck can receive assistance with heavy or bulky loads. The hook disposed in the ramp can be easily attached to the hand truck, and the system facilitates moving the hand truck up the ramp or down the ramp under remote radio control. The load assist system  16  is operable to provide the benefit of added safety by supporting the weight of the load as well as guiding the travel of the hand truck on the ramp. 
     The features of the present invention which are believed to be novel are set forth below with particularity in the appended claims. However, modifications, variations, and changes to the exemplary embodiments described above will be apparent to those skilled in the art, and the system and method described herein thus encompasses such modifications, variations, and changes and are not limited to the specific embodiments described herein.