Abstract
A tension monitoring device that attaches or clamps onto to a tensioned cargo load securing strap and wirelessly communicates the tension level to the driver via a remote device, such as a mobile smartphone. One or more devices may be installed on a vehicle or trailer to be simultaneously monitoring the tension conditions during transit. The tension signal from the device is received and processed by the mobile smartphone application to display the real-time tension relative to unsafe levels and transmit alerts to the driver when an unsafe or undesired condition occurs. The tension monitoring device includes an electromechanical sensor and microprocessor, powered by a battery, and packaged inside two hinged weatherproof housings for the ability to clamp onto a tensioned cargo strap.
Claims
1. A cargo strap tension level monitoring device comprising of: an upper and lower housing connected by a hinge that is clamped or secured onto a cargo strap; wherein the upper and lower housings are latched together on the opposite side of the housing hinge; wherein the cargo strap rests on two rigid supports and is contacted by a spring-loaded sensor mechanism between the supports such that the strap forces deflect the sensor as a function of strap tension; wherein the spring-loaded sensor includes a magnet interacting with a hall affect proximity sensor.
2. The cargo strap tension level monitoring device of claim 1, wherein the device can be installed by clamping onto any cargo strap, in tension or loose, without the need to feed the strap through the device or connect to any hooks. This offers the versatility and ease of installation and uninstallation of the device without affecting the securement of the straps.
3. The cargo strap tension level monitoring device of claim 1, wherein the device contains a battery, microprocessor with wireless communication capability, and a sensor, such as hall effect proximity sensor.
4. The cargo strap tension level monitoring device of claim 1, wherein the device wirelessly communicates the tension signal to a remote mobile smartphone application.
5. The cargo strap tension level monitoring device of claim 1, wherein the device wirelessly communicates all device health information to the remote mobile smartphone application, such as remaining battery charge life.
6. The cargo strap tension level monitoring device of claim 1, wherein the mobile smartphone application monitors for significant changes in tension from the preset tension value and when tension is near or below a calibrated low value.
7. The cargo strap tension level monitoring device of claim 1, wherein the mobile smartphone application alerts the driver to significant changes or unsafe levels of tension through visual, audible, and physical alerts, such as vibration.
8. The cargo strap tension level monitoring device of claim 1, wherein the mobile smartphone application records the global positioning system location at the time of the unsafe tension condition.
Description
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0012] Aspects of the embodiments described above are better understood with reference to the accompanying drawings, in which:
[0013] FIG. 1 is an illustration of a cargo load that is secured to a flatbed trailer with tensioned straps. The illustration also includes the tension monitoring system wirelessly communicating the tension signal to the mobile smartphone device located in the cab of the truck. There are two monitoring devices shown in this view, one on each strap.
[0014] FIG. 2 is a rear view of the truck and trailer to further illustrate the tension monitoring device installation and wireless communication. There is one tension monitoring device shown in this view.
[0015] FIG. 3A shows an isometric view of the monitoring device installed on a strap.
[0016] FIG. 3B shows an isometric view of the monitoring device installed on a strap, like FIG. 3A, but from the other side.
[0017] FIG. 4A is an isometric view of the monitoring device that is un-clamped on the tensioned strap to illustrate the clamping installation on the strap.
[0018] FIG. 4B is a side view, parallel to the strap, of the monitoring device that is un-clamped to illustrate the installation on the strap and include a view of the internal electromechanical sensor mechanism.
[0019] FIG. 5A is a side view of the monitoring device, parallel to the strap, to illustrate where the cross section in FIG. 5B is taken in perspective of. In addition, FIG. 5A shows the internal electromechanical sensor mechanism and the device installed on the strap in the clamped state.
[0020] FIG. 5B is a cross section view of the device, sliced parallel to the strap according to FIG. 5A, to further illustrate internal electromechanical sensor mechanism.
[0021] FIG. 6 illustrates the primary electrical circuitry of the device and the communication with the mobile smartphone application which displays tension levels.
DETAILED DESCRIPTION OF THE INVENTION
[0022] FIG. 1 shows a concept of the exemplary embodiment tension monitoring device 31 in use on a truck 13 and flatbed trailer 12 transporting cargo 11. Multiple cargo loads 11 are secured to the trailer 12 using a tensioned strap 14, such as a ratchet strap. This concept illustrates the use of multiple monitoring devices 31 wirelessly communicating 63 the tension signals 62 to the mobile smartphone 61. While in use, the mobile smartphone 61 is in the cab of the truck 13 displaying all tension signals 62 and alerts for the driver through the smartphone application.
[0023] FIG. 2 is an additional view of the exemplary embodiment tension monitoring device 31, similar to FIG. 1, but from the rear of the truck 13 and trailer 12. This further illustrates the device 31 in use and wirelessly communicating 63 the tension signal 62 to the mobile smartphone 61.
[0024] FIGS. 3A and 3B are isometric views of the tension monitoring device 31 installed on a strap 14. The device assembly 31 includes an upper housing 35 and upper housing cap 38 which are connected by a hinge 36 to a lower housing 34 and lower housing cap 37. The device 31 is clamped and secured to the strap 14 when the upper 35 and lower 34 housings pivot about the hinge 36 and close tightly around the strap 14. The housing 35 and 34 are then latched together using the latch 33 which has a hinge 32 that is integrated into the lower housing 34. The indicator window 39 is made of a transparent or translucent material to allow colored light indicators from the internal electronic circuitry to be seen by the user of the device 31. These are indicators such as, but not limited to, battery 49 charge status or wireless connection 63 status.
[0025] FIG. 4A is an isometric view and 4B is a side view of the tension monitoring device 31 while in the unclamped or unsecured state, prior to installation on the strap 14. From these views, it can be seen how the upper 35 and lower 34 housings pivot about hinge 36 as well as the latch 33 pivoting about the hinge 32.
[0026] Further detail of the internal electromechanical sensor components can be seen in FIG. 4B. There is a printed circuit board assembly 48 which includes a sensor, such as a hall effect proximity sensor 44, as well as a microprocessor chip 45 that has wireless communication capabilities, such as Bluetooth or WiFi. The electronic components are powered by a battery 49. The circuit board assembly 48 is secured to the upper housing 35 using fasteners 46. The circuit board assembly 48 is protected from the spring forces by the spring pad 47 which contacts the spring 43. The spring 43 forces the magnet 42 and magnet holder 41 against the strap 14. The magnetic flux from the magnet 41 interacts with the proximity sensor 44 and is used to generate a tension value within the microprocessor 45 to be wirelessly transmitted. The holder 41 contacts the strap 14 when the device 31 is in the installed and clamped state. The spring-loaded magnet holder 41 and magnet 42 will deflect into the upper housing 34 from the contact force of strap 14 in tension.
[0027] Further detail of the internal components and mechanism can be seen in FIGS. 5A and 5B. FIG. 5A is a side view of the tension monitoring device 31, like FIG. 4B, but FIG. 5A is in the clamped state and installed on strap 14. The dotted line and arrows in FIG. 5A describe the cross-section view that is shown in FIG. 5B.
[0028] FIG. 5B shows the internal mechanism and how the strap 14 interacts with the spring-loaded magnet holder 41 and rigid supports that are integrated into lower housing 34. Using a known height and spacing between the two supports and a known spring constant in spring 43 contacting the strap 14, the tension in the strap 14 can be calculated from the change in proximity of the magnet 42 to the sensor 44.
[0029] FIG. 6 is a schematic of the primary components of the electrical circuit board assembly 48 and the interaction with the mobile smartphone 61 application. The primary components on the printed circuit board assembly 48 are the sensor 44 and microprocessor 45 with wireless capability 63. The assembly is powered by a battery 49. The general placement of the magnet 42 relative to the sensor 44 can also be seen. The magnet 42 and battery 49 are shown to be out of plane, compared to the circuit board assembly 48, as represented with the dotted lines. The microprocessor 45 wirelessly communicates 63 the tension information signal 62 to the mobile smartphone 61 application. The application contains monitoring software to process the signal 62 to display for the driver, such as, but not limited to, digital tension gauges 64 that indicate tension at the start of trip, acceptable variation in the pre-set tension, and a warning or alert feature indicating an unsafe or loss of tension condition.
