JPH03262083A - Position control mechanism for reading head - Google Patents

Abstract

PURPOSE:To improve bar code reading workability by automatically oscillating a reading head to a bar code readable area at the time of detecting a moving target to be read out in an irradiated range. CONSTITUTION:The reading head 1 supported by a supporting body so as to be oscillated radiates scanning beams to a bar code 3a or the like stuck to a target 3 to be read out and outputs a reading completion signal SH to a control part 6 at the time of completing the reading of the bar code 3a or the like. A sensor means 4 set up on the head 1 detects the entrance of the target 3 into a scanning beam readable range and outputs a signal SS to the control part 6 based upon a change in reflected light and the control part 6 inputs both the signals SH, SS and sends a driving signal SD to a driving device 5 to start the oscillating operation of the head 1. Thus, the reading workability of a bar code reader can be improved.

Description

[Detailed description of the invention] 【overview】

Regarding the position control mechanism of the reading head in a barcode reader, the purpose of this is to provide a position control mechanism for the reading head that can improve the reading workability of the barcode reader. a sensor means which is pivotably mounted on the reading head and outputs a signal corresponding to an object to be read that moves within the irradiation range of the scanning beam; a control unit that outputs a drive signal in response to input of a reading completion signal from the head, and a pivot point between the reading head and the support body receives the signal and causes the reading head to swing. It is configured by providing a driving device for operation.

[Industrial application field]

The present invention relates to a position control mechanism for a reading head, and more particularly to a position control mechanism for a reading head that reads bar codes and the like. In recent years, PO3 (Point
to of Saj! es) As systems are being widely introduced not only in large stores but also in small and medium-sized stores, barcode readers have come into widespread use as a means of inputting product information. Under these circumstances, there is a need for a barcode reader that is easy to operate and has high reading efficiency.

[Conventional technology]

FIG. 8 shows a conventional stationary type barcode reader that irradiates the operating beam downward to prevent the laser beam from directly entering the operator's eyes. The reading head 1 that irradiates the scanning beam is mounted on a support 2 consists of holding the product on 3
To read the barcode 3a affixed to the barcode 3a, move the product 3 in the direction of the arrow so that it enters the readable area of the reading head 1, or move the reading head 1 on the support 2 in the vertical direction using the stopper 20. The reading head 1 is held movably in rotational directions F and G by the threaded portions 21 and A, B, and is moved by an operator using the stop portions or threaded portions to perform a reading operation.

[Problem to be solved by the invention]

However, in the conventional example described above, it is necessary to adjust the product 3 or the reading head 1, and the barcode F3a
If the beam pattern of the laser or the like that irradiates the target is invisible, it is difficult to position the target and the reading workability is poor. The present invention has been made in order to eliminate the above-mentioned drawbacks, and an object of the present invention is to provide a reading head position control mechanism that can improve the reading workability of a barcode reader.

[Means to solve the problem]

FIG. 1 is a diagram showing the principle of the present invention. In the figure, 1 is a reading head swingably supported on a support 2, which irradiates a scanning beam onto a barcode 3a etc. attached to an object 3 to be read, and is controlled when reading of the barcode 3a etc. is completed. A reading completion signal SH is output to the section 6. 4 is a sensor means installed in the reading head 1;
It is detected that the object to be read 3 has entered the readable range of the scanning beam, and a signal SS is output to the control section 6 based on the change in reflected light due to the entry of the object to be read 3. This control section 6 receives the reading completion signal SH and the sensor means 4.
The drive signal SD is input to the drive unit N5 by inputting the signal SS from the
The drive device 5 operates to swing the rad 1 toward reading. In this case, it may be configured such that the swinging motion of the reading head 1 is counted by the counting means 13 and the swinging motion of the reading head 1 is stopped when a predetermined value is reached.

[Effect]

Based on the above configuration, in the present invention, based on the signal SS from the sensor means 4, until the reading completion signal SH is output or the object to be read 3 is removed from the irradiation range of the scanning beam, the 1 is oscillated, and the reader 1 is controlled to a posture that allows barcode reading. Furthermore, if the period during which the reading completion signal SH is outputted is too long during this operation, the oscillation is counted, and when the count value reaches a limit, the oscillation is stopped.

【Example】

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 2 shows a main control block according to an embodiment of the present invention. In the figure, 1 is a reading head which has an irradiation window (not shown) on the front, and the scanning beam from the irradiation window is transmitted to the product 3.
The barcode 3a attached to the barcode 3a is irradiated with light, and the reflected light is taken in again to decode the code of the barcode 3a. A sensor means 4 is attached to the upper front of the reading radar 1, and detects when the product 3 enters the readable range of the scanning beam when it is irradiated with the scanning beam. A signal SS based on the change in reflected light due to the change in the reflected light is sent to a control section 6, which will be described later. Further, the reading head 1 is pivotally attached to the support column 7 of the support body 2 at its lower end, and is able to swing around a pivot 8. A gear 9 is fixed to this pivot shaft 8, and is meshed with a transmission gear 10 of a motor 5a driven by a signal from the control section 6. Furthermore, a detection means consisting of a light emitting section 11 and a light receiving section 12 is provided at a position sandwiching the vicinity of the pivot shaft 8 of the reading head 1 . As shown in FIGS. 3 and 4, this detection means is such that when the reading head 1 is at the home position shown in FIG. As shown in Fig. 4(b), it is installed in a position where the light receiving section 12 can receive the light from the light emitting section 11 when the reader leaves the home position, and when the reader 1 moves away from the home position. Upon reception of light by the light receiving section 12, a signal SL is outputted to a counter 13, which is a counting means. 20 The counter 13 is configured to count the signal SL and output a time limit signal ST to the control unit 6 when the number of swings reaches a preset number of swings, thereby stopping the swinging operation of the reading head 1. has been done. As shown in FIG. 6, the control section 6 performs an AND output of the reading completion signal SH from the reading head 1, the time limit signal ST from the counter 13, and the signal SS from the sensor means 4. The drive signal SD is configured to generate a drive signal SD and output it to the drive device 5, into which the signal SS from the sensor means 4 is input, and the read completion signal S
When H is input, the output of the drive signal SD is stopped. Next, the operation of the above embodiment will be explained based on the flowchart shown in FIG. First, in the initial state, the reading head 1 is stationary at an intermediate position (home position) of the swing stroke, and the signals SS, SH, and ST are all held at Lo-. In this state, S output from the control section 6
D is at Lo-level as shown in FIG. 7, and the drive device 5 is not driven. After this, when product 3 enters the readable range (7th
At time ts) in Figure (a), the output signal SS from the sensor means 4 becomes
Since the SD changes from o- to the old gh, the SD becomes the old gh and drives the drive device 5, and the swinging operation of the reading head l starts. This swinging motion starts with a counterclockwise swinging motion from the home position shown in FIG. 4(a) (see FIG. 4(b)), and moves the reading range of the reading head 1. With this swinging motion, the light from the light emitting section 11 of the detection means that was blocked at the home position reaches the light receiving section 12, and a signal SL is output. Upon sensing the output of this signal SL, the counter 13 increments by one count, and the control section 6 switches the drive signal SD and inputs it to the drive device 5, and after once stopping the motor 5a, reversely rotates the reading head l. Change the rotation clockwise. This clockwise swinging motion blocks the light from the light emitting section 11, and when the reading head 1 passes the home position and rotates to a predetermined angle, this light reaches the light receiving section 12 again and the signal SL is output. , the counter 13 increments by one count, and the direction of swinging of the rad l is changed to reading in the same procedure as described above. As described above, while the reading head 1 is swinging while changing the swinging direction as the counter 13 advances, the reading head 1 reads the barcode 3a and receives the reading completion signal SH. Changed from Lo & 4 to old GH and changed to control unit 6
(time t in FIG. 7(a)), the drive signal SD changes from High to Lo-, and after returning the reading head 1 to the home position, the swinging motion is stopped, and the operator sends a signal that the work is complete. Further, if the reading head 1 cannot read the barcode 3a during the above-mentioned swinging operation and the counter 13 advances to a predetermined value, the signal ST goes low as shown in FIG. 7(b). The signal changes from to High and is output to the control unit 6 (time 11). Along with this change in signal ST, drive signal SD changes from old gh to Low, and after returning reading head 1 to the home position, the swinging operation is stopped and an unreadable sign is sent to the operator. Furthermore, if the product 3 is removed from the readable range of the reading head 1 before the reading head 1 reads the barcode 3a, as shown in FIG. 7(C), the signal SS from the sensor means 4 is changes from High to Lo- and is output to the control unit 6 (time to), and the drive signal SD is changed from the old gh
to Lo- to stop the swinging.

【Effect of the invention】

As is clear from the above description, according to the reading head position control mechanism according to the present invention, the reading head is automatically moved to the barcode readable area, so that barcode reading workability can be improved. .

[Brief explanation of drawings]

Fig. 1 is a diagram of the principle of the present invention, Fig. 2 is a control block diagram of the main parts of the present invention, Fig. 3 is a perspective view of the reading head, Fig. 4 is a diagram showing the swinging operation of the reading head, Fig. 5 6 is a block diagram of a control section, FIG. 7 is a chart showing signal timing, and FIG. 8 is a diagram showing a conventional example. In the figure, 1 is a reading head, 2 is a support, 3 is an object to be read, 4 is a sensor means, 5 is a drive device, and 6 is a control section.

Claims (1)

[Scope of Claims] [1] A reading head (1) for irradiating a scanning beam is pivotably mounted on a support (2), and a reading head (1) for irradiating the scanning beam is provided on the reading head (1). A sensor means (4) that outputs a signal (SS) corresponding to the object to be read (3) moving within a range, and an output signal (SS) from the sensor means (4).
SS) and a reading completion signal (S
a control unit (6) that outputs a drive signal (SD) in accordance with the input to the reading head (1) and the support body (2); A position control mechanism for a reading head, characterized in that it is provided with a drive device (5) that receives an input signal (SD) and causes the reading head (1) to swing. [2] Detection means (11, 12) that outputs a signal (SL) every time the swing of the reading head (1) is detected, and the output signal (SL) of the detection means (11, 12) is counted a predetermined number of times. 2. The reading head position control mechanism according to claim 1, further comprising a counting means (13) for outputting a signal (ST) to stop the swinging operation of the reading head (1) when the reading head (1) oscillates.