Apparatus for variably controlling work feed rate for cutting wood, metal and other materials

• US 6,701,816 B2
• Filed: 01/07/2002
• Issued: 03/09/2004
• Est. Priority Date: 11/07/1997
• Status: Expired due to Fees

• Current Assignee: Smith H. Reid
• Original Assignee: Simonds Industries Incorporated (Simonds International Corporation)
• Inventors: Smith, H. Reid
• Primary Examiner(s): Peterson, Kenneth E.
• Application Number:
  US10/041,644
• Publication Number:
  US 20020059856A1
• Time in Patent Office: 792 Days
• Field of Search: 83/13, 83/72, 83/74, 83/75, 83/76, 83/768, 83/769, 83/761, 83/766, 83/767, 837/89, 83/56, 900/170, 900/174
• US Class Current: 83/74
• CPC Class Codes: B23D 59/001 Measuring or control devices, e.g. for automatic control of work feed pressure on band saw blade measuring in general G01; controlling in general G05
• CPC Class Codes: Y10T 83/148 Including means to correct the sensed operation
• CPC Class Codes: Y10T 83/152 And modify another operation
• CPC Class Codes: Y10T 83/159 Including means to compensate tool speed for work-feed variations
• CPC Class Codes: Y10T 83/18 With operator input means
• CPC Class Codes: Y10T 83/7076 With programming means
• CPC Class Codes: Y10T 83/7226 With means to guard the tension
• CPC Class Codes: Y10T 83/7264 With special blade guide means

Abstract

A positioned sensing device measures and/or calculates the lateral position and movement of a saw blade. These measured and calculated values are used to automatically alter the work-feed rate and/or saw blade rim speed either up or down as sawing conditions change within the work piece or between different work pieces.

Claims

1. An apparatus for variably controlling the feed rate of material to be cut by a saw having a saw blade and a wearable guide block, said apparatus comprising:

a sensor, said sensor for establishing a zero reference point for the lateral position of the saw blade, said sensor for detecting lateral movement of the saw blade away from said zero reference point when the saw blade is cutting material being fed into said saw blade;

a primary signal conditioning means for generating a generated signal proportional to the detected lateral movement of the saw blade; and

a control unit for controlling the feed rate of the material, said control unit establishing a reference signal proportional to said generated signal, said reference signal established at a preselected acceptable lateral movement of the saw blade, said control unit generating a comparative signal proportional to the difference between said generated signal and said reference signal, wherein if said generated signal is less than said reference signal then said control unit continuously increases the feed rate at a rate proportional to said comparative signal, and wherein if said generated signal is greater than said reference signal then said control unit continuously decreases the feed rate at a rate proportional to said comparative signal;

wherein said control unit and said sensor automatically and periodically reestablish said zero reference point to compensate for guide block wear and build up.

2. An apparatus for variably controlling the feed rate of material to be cut by a saw having a saw blade and a wearable guide block, said apparatus comprising:

a sensor, said sensor for establishing a zero reference point for the lateral position of the saw blade by determining the position of said saw blade prior to sawing material, said sensor for detecting lateral movement of the saw blade away from said zero reference point when the saw blade is cutting material being fed into the saw blade;

a primary signal conditioning means for generating a generated signal proportional to the detected lateral movement;

a control unit for controlling the feed rate of the material, said control unit generating a first reference point established at a preselected acceptable lateral movement of the saw blade, said control unit generating a second reference point established at a first level of unacceptable lateral movement of the saw blade, said control unit for generating a first comparative signal proportional to the difference between said generated signal and said first reference point, said control unit for generating a second comparative signal proportional to the difference between said generated signal and said second reference point;

wherein if said generated signal is less than said first reference point, then said control unit continuously increases the feed rate at a rate proportional to said first comparative signal, wherein if said generated signal is greater than said first reference point and less than said second reference point, then said control unit neither increases nor decreases the feed rate, wherein if said generated signal is greater than said second reference point, then said control unit continuously decreases the feed rate at a rate proportional to said second comparative signal; and

means for automatically and periodically reestablishing said zero reference point to compensate for guide block wear and build up.