Timelines in a Patent that Claims a Method

A picture is worth a thousand words.  Various figures may be included in a patent application for aiding the  description of the invention.  In a patent application claiming a control system method or process, a flow chart showing the steps of the method is usually necessary.  In addition to the flow chart, it may be beneficial to include a timeline figure illustrating the operation of the actuators and/or sensors, and the change in parameters when implementing the method. 

Though there may be some overlap of coverage between the flow chart and the timeline, the two figures are complimentary to each other, and may be utilized during prosecution to aid the application from different perspectives.  For example, the flow chart may emphasize the actions, such as the action of opening a valve, turning on a component, or reading a sensor, while the timeline may emphasize the other aspects of the action, such as increased air flow responsive to the opened valve.  The flow chart may emphasize the sequence of the steps, while the timeline may emphasize of the timing of the steps.  The flow chart may be used to delineate various embodiments of the method, while the timeline may be used to show a specific embodiment that can achieve certain advantages.   

When drawing a timeline, it is important that each axis of the timeline is defined as complete as possible.  If possible, information such as the range of the values, zero value, and the trend of changes (increasing or decreasing) should be clearly marked on the axis. This information may become important to overcome some unforeseen prior art or rejections constructed based on the broad interpretations by patent examiners or defendants in litigation.  For example, when claiming closing the valve positioned in a coolant passage, an Examiner may interpret the valve to be either completely closed with no coolant flow through, or partially closed with decreased coolant flow rate.  If timelines showing the value of coolant flow rate and the valve position are included in the application, the claim may be amended and clarified based on the timeline. 

So, when preparing your patent application, consider including timelines of system methods and operation as they might make the difference in the end.