Patent Publication Number: US-2011068172-A1

Title: Rotary one-dimensional barcode reading device

Description:
(a) TECHNICAL FIELD OF THE INVENTION 
     The present invention generally relates to a rotary one-dimensional (1-D) barcode reading device, and more particularly to a direction-independent 1-D barcode reading device, which is realized by rotating an existing direction-dependent 1-D barcode reader with a motor. 
     (b) DESCRIPTION OF THE PRIOR ART 
     One-dimensional (1-D) barcodes have been in existence for more than half a century. The general idea of the 1-D barcode reading is to irradiate a light source to a barcode and then receive the light reflected by the barcode, followed by converting the received reflection light into electronic signal. The electronic signal is then decoded by a decoder to determine the commodity associated therewith. The light source used include for example light-emitting diode (LED) and laser diode and the receiver for the reflection light include for example a charge-coupled device (CCD), a complementary metal-oxide semiconductor (CMOS) device, and a photo diode. General reading of a 1-D barcode requires setting the light source to completely cover the barcode, as shown in  FIG. 1 . It is often to make the light source, which is indicated by reference characters  02  in  FIG. 1 , a linear device. CCD and CMOS as employed in a receiver in this respect are also arranged as a linear CCD/CMOS sensor. Photo diode can be made movable with laser beam to also make a linear sensor. With such an arrangement, both the light source and the receiver have to be properly positioned in a manual manner to align the light source  02  in a direction normal to the barcode  01 , as shown in  FIG. 1 , before reading can be properly carried out. The alignment is time-consuming and elaborate operation. To cope with such a problem, 1-D barcode readers that require no alignment, referring to as direction-independent barcode reader herein, is available and the operation principles are as follows: 
     (1) A laser is used as a light source. A polygonal mirror is rotated to re-direct and project a plurality of laser beams in various directions. At least one of the laser beams may get oriented substantially normal to the barcode to be read regardless the direction in which the barcode is positioned. Reading of the barcode can thus be done correctly. However, the mechanical arrangement is complicated and elaborate, making it very expensive. 
     (2) LEDs are used as light sources. Photographing means is taken to picture the whole barcode, which is received by a rectangular array of CCD or CMOS sensors to convert to an electronic signal. Numerous electronic signals are then analyzed to obtain the desired 1-D barcode signal. An example is shown in U.S. Pat. No. 7,428,991. The disadvantage is that a large number of light sources is needed in order to cover the whole area of the barcode. The CCD/CMOS sensor array is much more expensive than a linear CCD/CMOS sensor. Increasing the number of pixels makes the amount of signals to be analyzed increased and the decoder used must be upgraded or faster. All lead to high costs. 
     SUMMARY OF THE INVENTION 
     A primary objective of the present invention is to provide a rotary one-dimensional (1-D) barcode reading device, wherein an existing direction-dependent 1-D barcode reader is manipulated with rotary motion performed by a motor to realize a direction-independent 1-D barcode reading device. 
     The rotary 1-D barcode reading device as described above comprises a motor and a 1-D barcode reader attached to the motor shaft so as to allow the reader to rotate with the motor shaft, by which linearity of the light source and the receiver of the barcode reader are converted into circularity to realize direction-diversified linear light sources and receives in various directions. Input and output of power source and signals are performed through electrical brushes. With this arrangement, a 1-D barcode in any direction can be properly read and the electronic signal generated by the 1-D barcode so read is transmitted through the electrical brushes or in a wireless manner to a computer, a point-of-sale (POS), a personal digital assistant (PDA), and the likes. 
     The rotary 1-D barcode reading device may comprise a plurality of electrical brushes and insulation must be made between the electrical brushes. Besides a grounding line of an electrical power source, other lines of the electrical power source must be arranged in such a way that an insulation ring is first fit over the shaft and a metal ring is further fit thereon. The wiring line of the metal ring must penetrate the insulation ring to connect to the barcode reader, or a hollow shaft is used to facilitate the wiring line to extend to and connect to the barcode reader. Alternatively, a shaft made of insulation may be adopted to omit the use of the insulation rings. 
     In the rotary one-dimensional barcode reading device described above, if a direct-current (DC) motor is taken as the motor that drives the shaft, the DC motor may share the same power source with the barcode reader. 
     In the rotary one-dimensional barcode reading device described above, an additional light source is provided to generate a light spot for aligning to a center of a barcode to be read so as to facilitate the reading of the barcode. The light spot will be off when the LED light source is on for eliminating interference. 
     In the rotary one-dimensional barcode reading device described above, the motor and the light source of the barcode reader can be arranged to power on at the same time or in an independent manner wherein due to the time period desired to completely actuate the motor, the motor can be kept in a condition of continuous rotation at a constant speed so as to improve the reading efficiency of barcodes. Alternatively, the light source can be arranged to power on only when a barcode is approaching. 
     In the rotary one-dimensional barcode reading device described above, the light source can be visible light or invisible light. 
     In the rotary one-dimensional barcode reading device described above, the barcode reading device can be arranged in a fixed type, a handheld type, or a gun type. 
     The foregoing objectives and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts. 
     Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view illustrating reading a barcode in a conventional way. 
         FIG. 2  is a schematic view illustrating the structure of a rotary 1-D barcode reading device in accordance with a first embodiment of the present invention. 
         FIG. 3  is a schematic view illustrating the structure of a rotary 1-D barcode reading device in accordance with a second embodiment of the present invention. 
         FIG. 4  is a schematic view illustrating the structure of a rotary 1-D barcode reading device in accordance with a third embodiment of the present invention. 
         FIG. 5  is a schematic view illustrating the structure of a rotary 1-D barcode reading device in accordance with a fourth embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following descriptions are exemplary embodiments only, and are not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Various changes to the described embodiments may be made in the function and arrangement of the elements described without departing from the scope of the invention as set forth in the appended claims. 
     Referring to  FIG. 2 , a first embodiment of the present invention is shown. The present invention is constructed to comprise an existing direction-dependent 1-D barcode reader  10 , which is known in the art, having a light source  02  that is linear and the same as that shown in  FIG. 1 . The linear light source  02  must be manipulated in a manual manner to align to the direction normal to a barcode  01  in order to read the barcode  01 . The present invention mainly comprises a motor  11  and the shaft  12  mounted to the motor  11 . The barcode reader  10  is mounted to the shaft  12 , whereby when the motor  11  is put into rotation, the light source of the barcode reader  10  is converted from a linear form into a circular light irradiation surface  13  as shown in the drawing. The light irradiation surface  13  is sized to completely cover the barcode  14 . Consequently, regardless of the direction in which the barcode  14  is positioned, the barcode  14  can be properly read. The light source used can be visible or invisible. 
     The present invention comprises electrical brushes  15 A,  15 B,  15 C,  15 D; insulation rings  16 A,  16 B,  16 C, metal rings  17 A,  17 B,  17 C; power lines  21 ,  22  for powering the motor  11 ; and power lines  23 ,  24  for powering the barcode reader  10 . The power line  23  is a grounding line, which extends through the electrical brush  15 D and the shaft  12  to the barcode reader  10 . The power line  24  extends through the electrical brush  15 C and the metal ring  16 C and further penetrates through the insulation rings  16 B and  16 A to the barcode reader  10 . Signal lines  25 ,  26  for output are further provided. The signal line  25  penetrates the insulation ring  16 A to the metal ring  17 B to realize output transmission through the electrical brush  15 B, while the signal line  26  is connected to the metal ring  17 A for output transmission through the electrical brush  15 A. All the wires or lines must be insulation jacketed and the whole arrangement of the device can be a fixed type, a handheld type, or a gun type. 
     Referring to  FIG. 3 , in a second embodiment of the present invention, a direct-current (DC) motor is adopted. The DC motor may share the same power source with the barcode reader  10  and the wiring arrangement is illustrated in the drawing. 
     Referring to  FIG. 4 , in a third embodiment of the present invention, the shaft  12  is made hollow and the power line  24  extends through an aperture  27  into the hollow interior of the shaft  12 . Similarly, the signal line  25  extends from the inside to the outside of the shaft  12  through an aperture  28 . In this way, the insulation rings  16 A,  16 B can be past around. The manufacturing of the this arrangement may combine the insulation rings  16 A,  16 B,  16 C together as a unitary member. Or alternatively, a shaft made of insulation substance may be used and in this case, the insulation rings  16 A,  16 B,  16 C can be omitted. The metal rings  17 A,  17 B,  17 C can be mounted by adhesives or can alternatively fixed in the manner shown in the drawing with pins  18 A,  18 B,  18 C. 
     Referring to  FIG. 4 , the present invention may further comprises a laser light source that project a laser beam to a center of a barcode to be read as a pointing light spot  19  to facilitate reading. It will be switched off when the LED light source is switch on for eliminating interference. 
     Referring to  FIG. 5 , in a fourth embodiment of the present invention, wireless devices  29  and  30  are adopted to transmit and receive signal of the barcode read with radio signals. 
     In operation, the motor  11  and the light source  02  can be powered on at the same time. Or alternatively, the motor  11  can be activated to rotate at a constant speed and the light source  02  is powered on only when a barcode is to be read. Or alternatively, a proximity sensor may be used so that the light source  02  may be automatically powered on when a barcode is approaching. 
     The various embodiments illustrated above are example preferred forms for embodying the present invention and are not intended to constrain the scope of the present invention. 
     To summarize, the present invention mounts a barcode reader to motor shaft so that an existing direction-dependent 1-D barcode reader is converted into a direction-independent 1-D barcode reader through the rotation of the motor shaft. This is a novel arrangement that has never been proposed before. 
     While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.