Automatic range adjustment techniques for stand-mountable bar code scanners

• US 6,637,655 B1
• Filed: 06/08/2000
• Issued: 10/28/2003
• Est. Priority Date: 06/08/2000
• Status: Expired due to Fees

• Current Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Original Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Inventors: Russell, Garrett K., Schmidt, Mark S., Wilz, David M. Sr., Rockstein, George B., Hudrick, Donald T.
• Primary Examiner(s): St. Cyr, Daniel
• Application Number:
  US09/589,853
• Time in Patent Office: 1,237 Days
• Field of Search: 235/462.14, 235/462.22, 235/462.23, 235/462.25, 235/462.31, 235/472.01
• US Class Current: 235/462.14
• CPC Class Codes: G06K 7/10851 Circuits for pulse shaping, amplifying, eliminating noise signals, checking the function of the sensing device basic electronic circuitry H03

Abstract

By automatically adjusting the object detection mechanism of a bar code scanner from a long range mode of operation to a short range mode of operation, the scanner will remain capable of detecting and decoding bar codes even if the object detection mechanism repeatedly detects the presence of a background object. The techniques of the present invention commence when the bar code scanner is placed in a position such that the scanner'"'"'s object detection mechanism repeatedly detects a background object such as a counter top or conveyer belt. The object detection mechanism is set to the long range mode of operation if it is not already so set. In the case of a stand-mounted scanner, a test is performed to ascertain whether or not the scanner is in its stand, and the method will only proceed once the scanner is resting in the stand. Next, the scanner is programmed to wait for a predetermined amount of time, after which the operational mode of the object detection mechanism is changed from the long range mode to the short range mode. At this time, the object detection mechanism no longer detects the presence of the background object. The scanner will now detect any new objects that enter the field of view of the object detection mechanism, and attempt to read any bar codes which may be present

Claims

1. A method for use with a bar code scanner having:

(i) an object detection mechanism equipped to perform a long range mode of object detection and a short range mode of object detection, and (ii) a scanning mechanism equipped to generate and control a scanning beam, the method comprising the steps of;

(a) the object detection mechanism repeatedly detecting presence of a background object; and

(b) automatically placing the object detection mechanism in the short range mode of operation;

wherein the short range mode of operation specifies a first range upon which detecting presence of a background object will activate the scanning mechanism,

wherein the scanner will detect presence of new objects while the background object is still present, and

wherein the long range mode of operation specifies a second range upon which detecting presence of,a background object will activate the scanning mechanism, such that the second range is greater than the first range.

2. The method of claim 1 further including the step of introducing a predetermined time delay prior to the performance of step (b).

3. The method of claim 2 wherein the predetermined time delay is greater than 0 seconds but less than twenty seconds.

4. The method of claim 3 wherein the predetermined time delay is less than one second.

5. The method of claim 1 wherein the background object is a countertop.

6. The method of claim 1 wherein the background object is a conveyor belt.

7. The method of claim 1 wherein the bar code scanner is adapted for repeated insertion into, and removal from, a stand.

8. A method for use with a stand-mountable bar code scanner having a scanning mechanism equipped to produce and control a scanning beam, a processing mechanism and an object detection mechanism equipped to perform a long range mode of object detection and a short range mode of object detection, the method comprising the steps of:

(a) the object detection mechanism repeatedly detecting a background object;

(b) setting the object detection mechanism to the long range mode of operation if the object detection mechanism is not already so set;

(c) the processing mechanism performing a test to ascertain whether or not the scanner is in the stand;

(d) once the scanner is in the stand, the processing mechanism waiting for a predetermined amount of time, after which the processing mechanism changes the mode of the object detection mechanism from the long range mode to the short range mode, wherein the short range mode of operation specifies a first range upon which detecting presence of a background object will activate the scanning beam and the scanning mechanism, and wherein the long range mode of operation specifies a second range upon which detecting presence of a background object will activate the scanning mechanism, such that the second range is greater than the first range.

9. The method of claim 8 further comprising the step of the object detection mechanism no longer detecting the presence of the background object.

10. The method of claim 9 wherein the scanner will now detect any new objects that enter the field of view of the object detection mechanism, and attempt to read any bar codes which may be present.

11. The method of claim 8 wherein the background object is a countertop.

12. The method of claim 8 wherein the background object is a conveyor belt.