Patent Application
20060074513
The invention relates generally to tool usage monitoring systems, and more particularly to a system and method for monitoring tool usage for calibration verification or replacement purposes.
A measuring device typically is calibrated to ensure that the device will provide an accurate measurement when it is used to take a measurement. Calibration is a process to standardize a measuring device by determining the amount of deviation between a measurement taken by the measuring device and a standard. The deviation of the measurement from the standard is then used to apply a correction factor to the measuring device so that the measuring device produces an accurate measurement. It may be desirable to periodically check the calibration of the measuring device and/or re-calibrate the measuring device. For example, wear and tear on the measuring device caused by the use of the measuring device may cause the device over time to begin providing erroneous measurements. Periodically checking the calibration or re-calibrating the measuring device enables a user to have confidence that the measurements taken with the measuring device are accurate. In addition, certain measuring devices and tools may have a limited lifetime and must be replaced once the lifetime of the measuring device or tool is complete.
Prior attempts to maintain the calibration of measuring devices have focused mainly on scheduling the measuring devices for a check of the calibration or a recalibration after a specified period of time has elapsed from a previous calibration check or calibration. However, this is not an efficient scheme for maintaining a measuring device calibrated as the tool may sit unused for significant periods of time. Therefore, the measuring device is not experiencing the type of usage that would tend to cause the device to begin providing erroneous measurements. Alternatively, the measuring device may be used to a greater extent than expected. Thus, the device may become un-calibrated due to excessive usage. Similarly, a calibration check of the measuring devices may be scheduled based on the number of days that the device is used, regardless of the amount of usage on a given day. However, this method is also inefficient, as it also does not accurately reflect actual wear and tear on the device. Alternatively, the relevant usage data, such as the number of actual uses, may be collected. However, this is usually done manually. For example, the use of the device may be logged by hand in a logbook. However, these types of manual data collection methods are usually inefficient and can lead to errors in data collection and analysis. As a result, a tool may be checked for calibration too infrequently and thereby become un-calibrated before its scheduled calibration check. Alternatively, the tool may be checked for calibration too frequently, thereby adding unnecessary expense and loss of productivity.
In addition, attempts have been made to schedule preventative maintenance or even tool replacement using similarly inefficient methods. For example, a tool may be scheduled for replacement after a predetermined calendar life or after a predetermined number of days in use.
Furthermore, such attempts have been in a manner that either obstructs or interferes with the normal course of production. For example, one method of monitoring daily usage of a measuring device is to require the device to be checked out from a tool crib each day or at the beginning of a shift. Thus, the tool must be returned to the tool crib at the end of the day or at the end of the shift. With large devices, this may mean locking the device when not in use and requiring a user to check out the key to the lock from the tool crib to enable the user to operate the device. Consequently, these methods reduce the efficiency of production.
Therefore, there is a need for an efficient system or method for ensuring that measuring devices or tools are maintained in condition to provide accurate measurements. In addition, there is a need for a system or method for maintaining the device calibrated that minimizes interference with the operation of the device or inconvenience to the user of the measuring device or tool.
According to one aspect of the present technique, a tool usage monitoring system and method is provided. The system comprises a sensing element for detecting when a tool is in use and producing a signal representative of tool usage. A processor-based device that is communicatively coupled to the sensing element is also provided. The processor-based device is programmed to maintain a running total of tool usage based on the signal representative of tool usage. The processor-based device also is operable to store a defined tool usage total corresponding to the tool. The system further comprises a user interface coupled to the processor-based device. The processor-based device is programmed to send a signal to the user interface when the running total of tool usage either equals or exceeds the defined tool usage total. The system is also capable of monitoring usage of a plurality of tools.
In accordance with another aspect of the present technique, a computer program is provided. The program comprises programming instructions that direct a processor to receive usage data of the calibrated device and produce a signal to indicate to a user to check calibration of the calibrated device when a running total of usage of the calibrated device achieves a predefined amount of usage.
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
In the subsequent paragraphs, various aspects of a technique for automatically monitoring the usage of a tool in a workplace will be explained. The various aspects of the present techniques will be explained, by way of example only, with the aid of figures hereinafter.
Referring generally to
In the illustrated embodiment, a communications module 16 is coupled to each tool 12 to transmit tool usage data corresponding to the use of the tool 12 to a receiver module 18. The communications module 16 may also transmit the unique identifier associated with the tool 12 to the receiver module 18. As illustrated, the communications module 16 and receiver module 18 are in wireless communication. However, wired communication between the communications module 16 and the receiver 18 may also be used. The tool use data is received by the receiver 18 and stored in a database 20 located in a central monitoring station 22. In addition, a processor-based device 24 is coupled to the database 20 to utilize the data stored in the database for analysis and decisioning. If the usage data for a tool 12 indicates that the tool 12 has been in operation for a defined period of time, or for a defined number of uses, or a combination of both the number of uses and the duration of use corresponding to a maintenance activity, the processor-based device 24 produces a signal to inform a maintenance person to perform a maintenance check for the tool 12. Recalibration or replacement may then be effected accordingly.
The central monitoring station 22 also comprises a keyboard 26 for entering data into the processor-based device 24, such as the defined amount of usage that a particular tool 12 may be in use before a calibration check or replacement should be performed, and the results of maintenance performed on the tool. The defined amount of usage may be changed depending on the result of the maintenance activity performed on the tool or device. For example, it may be established that the tool does not need to be calibrated as often as it is currently scheduled. Consequently, the defined amount of tool usage may be increased. Conversely, it may be discovered that the tool should be checked more often than the currently defined usage. A user may enter data corresponding to each tool 12 located in the workshop, factory, or manufacturing plant via the keyboard 26. Alternatively, the user may enter data corresponding to each category of tools. A display monitor 28 is also present in the central monitoring station 22 for displaying information. Alternatively, the analysis of the data may be available globally via the Internet or other networked systems. Such an analysis may include, but may not limited to, the total of tool usage, the number of times the tool was used, the duration of use, etc. The analysis may also include a notification that a tool has achieved a defined amount of usage corresponding to a maintenance activity to be performed on the tool 12, the results of any maintenance performed on the tool, current tool use statistics, the tool inventory, and the like, for all of the tools 12 coupled to the central monitoring station 22. Using the keyboard 26, the monitor 28, and the Internet, a user may check the current usage statistics of any tool 12 coupled to the central monitoring station 22.
Referring generally to
The illustrated embodiment of the tool usage monitoring system 10 comprises the hardware interface 14, the communications module 16, the receiver module 18, and the central monitoring station 22. As noted above, the hardware interface 14 is operable to establish whether the tool 12 is in use or not. The actual usage data is coupled to the communications module 16 for transmission to the receiver module 18. The receiver module 18 couples the actual usage data to the central monitoring station 22. The processor 24 (shown in
The hardware interface or sensor 14 comprises a sensing element 30 that is operable to detect when the tool 12 is in use. The sensing element 30 is coupled to the tool 12 and an optional local storage and processing device 32 in this embodiment. The sensing element 30 is adapted to provide a signal to enable the system to identify periods of actual usage of the tool 12. The tool usage data may be used to inform a user when a desired activity should be performed, such as periodic maintenance on the tool or even replacement of the tool. Depending on the application of the tool, various embodiments of the sensing element 30 may be used. For example, if the tool is a gage, the sensing element 30 may be a proximity sensor operable to provide an indication when an object to be measured is disposed on the gage. The following are examples of various types of sensors that may be used for detecting when a tool is in use or when the tool is not in use: a low voltage conductivity switch, a magnetic sensor, a laser sensor, an LED sensor, an infrared laser sensor, an infrared LED sensor, a rotating speed sensor, a spin sensor, a position sensor, a level sensor, a magnetic switch, a contact switch, an impact sensor, an acceleration switch, a direction sensor, a vibration sensor, a pressure sensor, a motion sensor, an acoustic sensor, a door or window sensor, or any of a variety of other sensor types. In addition, if the tool is electrically powered, such as a multi-meter, the sensor 14 may be coupled to an operating switch to indicate when the device is turned on and when the device is turned off.
The tool usage data generated by the sensing element 30 may be transmitted to the central monitoring station 22 for analysis and storage or it may be stored in the local storage and processing device 32 for preliminary processing. In this embodiment, the local storage and processing device 32 converts the various forms of sensed data into a format for easier communication. Also, the sensor data may be converted into data that can be used and processed locally. For example, in this embodiment, the local storage and processing device 32 processes the data from the sensing element 30 so as to provide an optional local display 34 with an indication of the duration of time that the tool has actually been in use overall or since a previous procedure was performed on the tool, etc.
The local display unit 34 may be utilized to display current statistical data of the state of the tools, and may also be utilized for displaying alerts when the tool requires a calibration check, replacement, or some other maintenance activity. A signal to inform a user that a calibration check, periodic maintenance, or some other activity, such as replacement of the tool is desired based on the amount of tool usage, may be provided from the processor 24 to the local display unit 34 when the amount of actual usage of the tool reaches a desired amount. Alternatively, the signal may be provided from the local storage and processing device 32 to the local display unit 34 or the signal may be processed at the central monitoring station 22 to be sent to relevant parties via e-mail, pager, cellular etc. The sensing element 30, the local storage and processing device 32, and the local display 34 are powered by a battery 36 in the illustrated embodiment. However, these components may also be coupled to a line source, as will be appreciated by one skilled in the art. As previously described, hardware interface 14 may further comprise a unique identification tag that identifies the tool, and the corresponding sensing element 30. In one embodiment, the identification tag helps in monitoring and collection of data and statistics of each tool of a plurality of tools monitored in a centralized manner.
The processed data is transferred from the tool to the data interface 18 and the processor 24 located in a central location through the communications module 16. The communications module 16 may be designed for wireless transmission of the processed sensor data. The communications module 16 comprises a communication interface 38 and a transmitter 40, such as a radio frequency (RF) transmitter that is operable to transmit RF data. However, other types of wireless communication may be used. In addition, a transceiver, rather than a transmitter, may be used when data is to be communicated from the receiver module 18 to the communications module 16. The transmitter 40 may be powered by a battery or alternatively be coupled to a line source.
The receiver module 18 has a receiver 42 that is operable to receive the data that is transmitted by the transmitter 40 of the communications module 16. The receiver 42 receives the sensor data and transfers the data to an application programming interface (API) 44. The function of the API 44 is to translate the sensor data that is received from the receiver 42 into a form that may be communicated to a corresponding API in the central monitoring station 22. An analysis engine 46 comprising the processor 24 and a program stored in the central monitoring station 22 enables a user to process the sensor data. The analysis engine 46 analyses the sensor data to establish whether the tool requires a calibration check, periodic maintenance, replacement, or some other activity based on the actual tool usage and set points stored in the central monitoring station 22 among other valuable information. The data generated by the analysis may be accessed globally via the Internet.
If the analysis engine 46 establishes that a desired activity should be performed, a signal is provided to the display unit 28 to display a request and/or an alert to inform the user that a desired action to the tool is to be performed. The display unit 28 may be configured to display the status of any tool that is linked to the system. Thus, the display unit 28 may function as the external user interface or output device. Alternatively, the status may be available via the Internet and notification to interested parties may be provided via e-mail, text message, etc. when an action is required. As previously described, the system may further comprise an input device such as a keyboard 26 for configuring the system for the various tools in the tool monitoring system 10.
It may be noted that one or more of the components of the tool monitoring system may be in a wireless or wired configuration. Also, computer readable instructions may be utilized to achieve the results, and in such a case, the computer readable instructions may be embedded in the processor 24, which may be a dedicated processor, such as an application specific integrated circuit (ASIC), or the instructions may be embedded in a micro-controller.
Referring generally to
The sensor data stored in the local storage and processing device 32, shown in
The sensor data may optionally be preprocessed before transmission to the central monitoring station 22 illustrated in
Referring to
As illustrated in
A different type of transmitter and receiver arrangement may be used, such as a combination of a photo-diode and phototransistor. In a different embodiment, a combination of a photo transceiver and a photo-reflective material may be used. For example, a laser transceiver may be disposed on one side of the gage 62 and a reflective material or a mirror may be disposed on the opposite side of the worktable to achieve the same results.
Referring generally to
Referring generally to
Referring generally to
The top-view of the gage 88 is illustrated in
Referring generally to
In an alternate embodiment, the transmitter 96 transmits the signal to the local storage and processing device 32, illustrated in
In a different embodiment, the usage of an electrically operated tool or gage may be monitored. For example, if the tool or gage is a multi-meter, such as multi-meter 94, the sensor 14 may be coupled to the switching mechanism of the multi-meter 94, such that whenever the multi-meter 94 is switched into an on state, the transmitter 96 will transmit a signal indicative of the operation of the multi-meter 94.
Referring generally to
Another method for detecting movement of a gear wheel 102 is by utilizing a magnetic sensor.
It may be noted that in the various embodiments illustrated in
As had been described above, proximity sensors and switches may be utilized for detecting tool usage. One example of proximity sensors and switches that may be used is a photoelectric proximity sensor, such as through beam type sensors, retro-reflective type sensors, diffuse type sensors, fiber optic type sensors, etc. Such types of sensors can be used in long ranges. Other examples of proximity sensors and switches are inductive proximity sensors, capacitive proximity sensors, magnetic proximity sensors, reed proximity sensors, and ultrasonic sensors. For detection of rotation and spin, hall-effect sensors and acoustic sensors may be utilized. Similarly, mechanical impact sensors and accelerometers may detect mechanical impact, which may be indicative of the beginning or end of operation of tools or calibrated devices. Mechanical tilt switches and mercury tilt switches may be used to detect tilting of the work piece on a worktable. Such tilt switches may be useful where the tool or the calibrated device tilts while in operation. A simple contact switch or a piezoelectric sensor may be used to initiate a timer circuitry when a tool or calibrated device or work piece is disposed on top of the same. Acceleration and inertia switches can be used for cases involving acceleration, spin, impact, recoil, directional and vibration sensing.
While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
