JP6357076B2 - Obstacle detection device for article shelf device - Google Patents

Description

  The present invention relates to an obstacle detection device for an article shelf device that detects an obstacle in a work space formed between movable shelves.

  In an article shelf apparatus having a plurality of shelves used in a warehouse, a library, etc., a movable shelf arranged on a rail extending in the front-rear direction laid on the floor is moved manually or electrically along the rail and adjacent to it. Some have improved the accommodation efficiency of articles in a limited space by forming a work space between arbitrary shelves. In such an article shelf device, when a moving shelf is moved when a person or an article is present in the work path, there is a possibility that the person or the article is sandwiched between the shelves.

  Therefore, there is an article shelf device that detects the presence of an obstacle such as a person or an article in the work passage using the obstacle detection device, and stops the traveling of the movable shelf based on the detection information. As an obstacle detection device, for example, there is one in which an ultrasonic distance sensor is provided below a front surface of a base that constitutes a lower portion of an opposed moving shelf (for example, Patent Document 1). This ultrasonic distance sensor measures the time when the output sound wave is reflected back to the opposite shelf, and the difference between the time until receiving this sound wave and the threshold is a predetermined time or more In addition, the obstacle detection device determines that the sound wave is reflected by an object other than the shelf, and can detect the presence of the obstacle in the work space.

Japanese Patent Laid-Open No. 5-186017 (page 2, FIG. 1)

  Since the obstacle detection device as in Patent Document 1 sets the distance between predetermined shelves as a threshold, when the distance between shelves is different from the predetermined distance, for example, when the shelves move Has a problem that the threshold cannot be used and the presence of an obstacle cannot be detected.

  The present invention has been made paying attention to such a problem, and an object of the present invention is to provide an obstacle detection device for an article shelf device that can reliably detect an obstacle regardless of the distance between shelves. And

In order to solve the above problems, an obstacle detection device for an article shelf device according to the present invention includes:
An obstacle detection device for an article shelf device that detects an obstacle in a work space formed between movable shelves placed on rails,
A plurality of non-contact distance sensors installed between the shelves, an inter-shelf distance measuring device that determines a threshold corresponding to the distance between the shelves, and the thresholds and the outputs of all the distance sensors are compared. And a detector.
According to this feature, the detection unit compares the threshold value determined by the inter-shelf distance measurement device with the outputs of all the distance sensors, and thereby outputs an output that is a difference greater than an allowable error with respect to the threshold value. It can be determined that the distance sensor to be measured has measured the distance to an object other than the other shelf, and it can be detected that there is an obstacle in the work space. Therefore, an obstacle can be reliably detected regardless of the distance between the shelves.

The inter-shelf distance measuring device is characterized by measuring the movement of the shelves and determining the threshold value.
According to this feature, since the threshold value is measured based on the actual movement of the movable shelf, the comparison with the output of the distance sensor can be performed accurately.

The detection unit includes an output unit that transmits a signal for stopping a driving unit used for moving the shelf based on a result of comparing the threshold value and outputs of all the distance sensors.
According to this feature, the shelf can be stopped immediately upon detection of an obstacle, so that safety is high.

The detection unit detects that there is an obstacle in the work space when a difference between the threshold and an output of at least one distance sensor is 30 mm or more in terms of distance.
According to this feature, it is possible to reliably detect an obstacle while avoiding erroneous detection.

The distance sensor is an ultrasonic sensor.
According to this feature, an obstacle detection apparatus can be configured with a small number of distance sensors by using an ultrasonic sensor with a wide detection range as a distance sensor.

It is a perspective view which shows the goods shelf apparatus in an Example. It is a block diagram which shows the aspect which the movement shelf moved to the one side. It is a block diagram which shows the calculation process of each shelf distance. It is a block diagram which shows the aspect which the movement shelf moved to the other side. It is a flowchart which shows a detection process.

  EMBODIMENT OF THE INVENTION The form for implementing the obstacle detection apparatus of the goods shelf apparatus which concerns on this invention is demonstrated below based on an Example.

  An obstacle detection device for an article shelf device according to an embodiment will be described with reference to FIGS. 1 to 5.

  As shown in FIGS. 1 and 2, an article shelf device 4 is disposed mainly in a library, a warehouse, or the like. The article shelf device 4 includes two rails 5 and 5 extending in parallel on the floor surface, fixed shelves 2A and 2B fixedly mounted on both ends in the longitudinal direction of the rails 5 and 5, and a fixed shelf 2A. , 2B, and motorized moving shelves 3A, 3B mounted so as to be movable along the rails 5, 5. In this article shelf device 4, the longitudinal dimensions of the rails 5 and 5 are longer by a predetermined length than the total dimension of the dimensions of the fixed shelves 2A and 2B and the moving shelves 3A and 3B in the moving direction. The work space can be formed by selectively separating the 2B and the movable shelves 3A and 3B from each other. In the present embodiment, the space between the fixed shelf 2A and the movable shelf 3A will be described as a work space S1, and the space between the movable shelves 3A and 3B will be described as a work space S2.

  Wheels (not shown) are provided on the bottom surfaces of the movable shelves 3A and 3B, and are placed on the rails 5 and 5 so as to be able to run on their own via the wheels. The movable shelves 3A and 3B have electric reversible motors 16 and 16 that are linked to the wheels. The reversible motors 16, 16 are connected to drive control devices 13, 13 that perform drive control of the article shelf device 4, and the movable shelves 3 </ b> A, 3 </ b> B are moved by rotating the reversible motors 16, 16 forward or backward. It can move along the rails 5 and 5. By adjusting the lengths of the rails 5 and 5 and the width of each shelf, the number of fixed shelves and movable shelves that can be arranged, the number and width of work spaces, etc. can be changed as appropriate. Yes.

  These fixed shelves 2A, 2B and movable shelves 3A, 3B have shelves 6, 6,... Having a plurality of upper and lower shelves that can display articles such as books. .. Are provided on the side surface in a detachable manner. A gap is formed between each of the shelves 6, 6,... And each of the decorative panels 7, 7,..., And various devices to be described later are incorporated in the gap.

  On the outer surface of the decorative panel 7 of the fixed shelf 2A, a power switch 8 of the entire article shelf device 4 and a monitor 9 that can be operated by a touch panel method are provided, and on the outer surface of the decorative panel 7 of the fixed shelf 2B, Only the manual operation button 14 is provided. On the outer surfaces of the decorative panels 7 and 7 of the movable shelves 3A and 3B, the manual operation buttons 14 and 15 are provided on both ends in the short direction, respectively.

  In addition, the article shelf device 4 includes an obstacle detection device 1 that detects an obstacle in the work space formed between the shelves. As shown in FIG. 2, the obstacle detection device 1 includes a detection unit 11 disposed in the decorative panel 7 of the fixed shelf 2 </ b> A, and sensor units 21, 22, 31, and 32 respectively provided at the lower part of each shelf. The rotary encoders 17 and 17 are provided mainly on the movable shelves 3A and 3B, respectively.

  The sensor unit 21 of the fixed shelf 2A includes distance sensors 2a to 2c directed to the movable shelf 3A side and a sensor control device 21a. Similarly, the sensor unit 22 of the fixed shelf 2B is a distance directed to the movable shelf 3B side. It consists of sensors 2d to 2f and a sensor control device 22a.

  The sensor unit 31 of the movable shelf 3A includes distance sensors 3a to 3c directed to the fixed shelf 2A side, distance sensors 3d to 3f directed to the movable shelf 3B side, and a sensor control device 31a. The 3B sensor unit 32 includes distance sensors 3g to 3i directed to the movable shelf 3A side, distance sensors 3h to 3m directed to the fixed shelf 2B side, and a sensor control device 32a.

  Each of these sensor control devices 21a, 22a, 31a, and 32a incorporates an operation program for operating the distance sensors 2a to 2c, 2d to 2f, 3a to 3c, and 3d to 3f at predetermined time intervals. The distance sensor operates at predetermined time intervals according to this operation program.

  Each distance sensor is an ultrasonic distance sensor having a sound wave output unit and a sound wave input unit (not shown), and the time required for the sound wave output from the sound wave output unit to be reflected on the opposite shelf and return to the sound wave input unit. The output is sent to the detection unit 11. By using an ultrasonic sensor having a wide detection range in the longitudinal direction of each shelf as a distance sensor, it is possible to output ultrasonic waves to almost all areas between the shelves with a small number of distance sensors. Moreover, each distance sensor which opposes is arrange | positioned and shifted | deviated to the longitudinal direction of each shelf, and the interference of the output of each distance sensor which opposes is suppressed.

  The distance sensors 2 a to 2 c of the sensor unit 21 and the distance sensors 3 a to 3 c of the sensor unit 31 measure the output value between the fixed shelf 2 </ b> A and the movable shelf 3 </ b> A facing each other in the detection unit 11. Are managed as a group. The distance sensors 3d to 3f of the sensor unit 31 and the distance sensors 3g to 3i of the sensor unit 32 are grouped as a sensor group β that measures an output value between the movable shelf 3A and the movable shelf 3B. The 32 distance sensors 3h to 3m and the distance sensors 2d to 2f of the sensor unit 22 are grouped as a sensor group γ that measures an output value between the movable shelf 3B and the fixed shelf 2B.

  The detection unit 11 appropriately selects the sensor groups α, β, and γ that are operated based on the moving directions of the movable shelves 3A and 3B, that is, based on the normal rotation and the reverse rotation of the reversible motors 16 and 16. It is not necessary to always operate the groups α, β, and γ, and power can be saved.

  The detection unit 11 is connected to the rotary encoders 17, 17, the power switch 8, the monitor 9, and the sensor units 21, 22, 31, 32. And wired or wireless connection. Furthermore, the detection unit 11 includes a transmission unit 12 that sends a drive signal and a stop signal to the drive control device 13. Although not shown here, the detection unit 11 and the drive control device 13 are connected by wire or wirelessly.

  The rotary encoders 17 and 17 and the detection unit 11 constitute an inter-shelf distance measuring device that can measure the inter-shelf distance. The rotary encoders 17 and 17 can read the rotation direction and rotation amount of each reversible motor 16 and 16, respectively, and send the rotation direction and rotation amount to the detection unit 11 as output each time the reversible motor 16 and 16 rotate. The detection unit 11 calculates the coordinates of the movable shelves 3A and 3B based on the output received from the rotary encoders 17 and 17 as needed, and the coordinates of the movable shelves 3A and 3B and the coordinates of the fixed shelves 2A and 2B. The distance between each shelf is calculated from time to time. The process for calculating the distance between the shelves will be described later.

  Next, various operation processes of the article shelf device 4 will be described. Here, only the operation processing mode of the moving shelf 3A will be described, and the description of the operation processing mode of the moving shelf 3B will be omitted.

  As shown in FIG. 2, when the manual operation button 15 is pressed while the movable shelf 3A is stopped, the pressing signal is sent to the detection unit 11, and the detection unit 11 detects the distance sensors 3d to 3d based on the pressing signal. Operate 3i. Outputs obtained from the distance sensors 3d to 3i via the sensor units 21, 22, 31, and 32 are sent to the detection unit 11, and the detection unit 11 outputs the output from the distance sensors 3d to 3i and the rotary encoder 17. , 17 based on the inter-shelf distance t3 of the movable shelves 3A, 3B calculated based on the outputs of, 17, a detection process for detecting the obstacle 18 in the work space S2.

  When it is confirmed by the detection process that there is no obstacle 18 in the work space S2, a drive signal is sent from the transmission unit 12 of the detection unit 11 to the drive control device 13, and the drive control device 13 causes the reversible motor 16 to move. Driving (here, normal rotation) is performed to move the movable shelf 3A in the direction of the manual operation button 15 (arrow direction). By the way, when the obstacle 18 in the work space S2 is detected by the detection process in the stop state of the movable shelf 3A, the detection unit 11 performs a process of not transmitting a drive signal to the drive control device 13 and an operation error. A process for displaying a message on the monitor 9 is performed.

  When the moving shelf 3A moves normally, the detecting unit 11 sends a stop signal to the drive control device 13 based on the inter-shelf distance t3 between the moving shelves 3A and 3B, which is calculated as needed. A normal stop process for stopping the shelf 3A at an appropriate position is performed.

  Next, the process for calculating the distance between the shelves will be described in detail with reference to FIG. As shown in FIG. 3, the detection unit 11 determines the distance from the end surface 2Aa on the movable shelf 3A side of the fixed shelf 2A to the end surface 2Ba on the movable shelf 3B side of the fixed shelf 2B, and the inter-shelf distance T1 between the fixed shelves 2A and 2B. As previously stored. Furthermore, the detection unit 11 stores the width W1 of the movable shelf 3A and the width W2 of the movable shelf 3B.

  Further, the detection unit 11 stores a point where the end surface 3Aa of the movable shelf 3A is in contact with the end surface 2Aa of the fixed shelf 2A as the origin position Z1 of the movable shelf 3A. As described above, each time the reversible motor 16 rotates in the forward rotation direction (arrow + direction) and the reverse rotation direction (arrow-direction), the rotary encoder 17 sends the rotation amount to the detection unit 11. Based on the output from the rotary encoder 17, the unit 11 performs a process of calculating the distance that the movable shelf 3A has advanced in the forward direction from the origin position Z1. The detection unit 11 stores the distance calculated by the above processing as the inter-shelf distance t1 between the fixed shelf 2A and the movable shelf 3A.

  The detection unit 11 stores a point where the end surface 3Ba of the movable shelf 3B is in contact with the end surface 2Ba of the fixed shelf 2B as an origin position Z2 of the movable shelf 3B. The distance traveled in the reverse direction from the position Z2 is calculated, and the distance is stored as the inter-shelf distance t2 between the fixed shelf 2B and the movable shelf 3B.

The detection unit 11 subtracts the total of the inter-shelf distance t1, the inter-shelf distance t2, the width W1 of the movable shelf 3A, and the width W2 of the movable shelf 3B from the entire inter-shelf distance T1. The inter-shelf distance t3 between 3A and the moving shelf 3B is obtained. That is, it is obtained by the following equation.
Shelf distance t3 = shelf distance T1- (shelf distance t1 + shelf distance t2 + shelf width W1 + shelf width W2)

  Next, the detection process will be described in detail with reference to FIG. 5, taking FIG. 4 as an example. FIG. 4 shows that when moving the movable shelf 3A in the direction of the fixed shelf 2A (arrow direction), the obstacle is not detected by the detection process when the manual operation button 14 (see FIG. 1) is pressed in the stopped state. FIG. 10 is a diagram illustrating a case where an obstacle 18 falls from the shelf 6 to the work space S1 after the movable shelf 3A starts moving.

  The detection process is continuously performed until the movement of the moving shelf is completed after the manual operation button is pressed while the moving shelf is in a stopped state. As described above, since the manual operation button 14 has been pressed and the movable shelf 3A has started to move, the detection unit 11 performs a process for calculating the distance between the shelves in step Sa1 in the detection process. Next, at step Sa2, the inter-shelf distance t1 between the fixed shelf 2A and the movable shelf 3A calculated at step Sa1 is determined as a threshold for comparing with the output of each distance sensor.

  Next, the detection unit 11 operates the sensor group α at a predetermined interval, and acquires outputs from all the distance sensors 2a to 2c and the distance sensors 3a to c in the sensor group α. The detection unit 11 converts each output received from the distance sensors 2a to 2c and the distance sensors 3a to c into a distance value in step Sa3 in the detection process.

  Next, in step Sa4, the distance values of all the distance sensors 2a to 2c and the distance sensors 3a to 3c in the sensor group α are compared with the threshold value.

  Subsequently, in step Sa5, it is determined whether or not there is one or more distance sensors whose difference in distance value with respect to the threshold is equal to or greater than an allowable error (30 mm). If it is determined that there is one or more distance sensors whose difference in distance value with respect to the threshold is equal to or greater than an allowable error, it is determined in step Sa6 that there is an obstacle 18 in the work space S1 based on the determination information, and the obstacle The detection process of the presence of the object 18 is completed.

  The detection unit 11 performs an emergency stop process of transmitting a stop process from the transmission unit 12 to the drive control device 13 based on the detection of the detected object.

  Thus, the threshold value is calculated by a method different from the distance sensors 2a to 2c and the distance sensors 3a to c by using the rotary encoders 17 and 17, and the threshold value and all the distance sensors 2a in the sensor group α are calculated. ~ 2c and distance sensors 3a-c are compared with each other so that it can be detected that there is an obstacle 18 in the work space S1, so the distance between the shelves is not fixed, especially during moving travel of the moving shelves. Even in the case, the obstacle 18 can be reliably detected. Further, for example, it is effective when there is a long or large obstacle in the work space S1 that straddles all the distance sensors 2a to 2c and the distance sensors 3a to 3c in the longitudinal direction of the fixed shelf 2A and the movable shelf 3A. .

  Moreover, since the detection part 11 will detect the obstruction 18 when there exists one or more distance sensors from which the difference of the distance value with respect to the said threshold value becomes the tolerance 30mm or more, each distance sensor 2a-2c and distance The obstacle 18 can be reliably detected while avoiding erroneous detection due to measurement errors of the sensors 3a to 3c.

  As described above, since the sensor control devices 21a and 31a output the distance sensors 2a to 2c and the distance sensors 3a to c every predetermined time by the output program, if there is no obstacle 18 in the work space S1. If it is determined, the process goes to step Sa1 to repeat the detection process. Since the detection process is repeated every predetermined time as described above, the obstacle 18 can be reliably detected even when the movable shelf 3A is traveling.

  In this embodiment, the rotary encoders 17 and 17 are used as the inter-shelf distance measuring device. However, for example, an ultrasonic sensor is provided at the upper end of each shelf that does not obstruct people's traffic and things. The output obtained by the ultrasonic sensor may be determined as a threshold corresponding to the distance between the shelves, and the threshold and the output of each distance sensor may be compared.

  In the present embodiment, the transmission unit 12 is built in the detection unit 11. However, the detection unit 11 and a separate transmission unit are provided in the decorative panel 7, and the detection unit 11 and the transmission unit are provided. May be connected.

  Although the embodiments of the present invention have been described with reference to the drawings, the specific configuration is not limited to these embodiments, and modifications and additions within the scope of the present invention are included in the present invention. It is.

  For example, although an ultrasonic sensor is used as the distance sensor in the above-described embodiment, the present invention is not limited to this, and may be substituted as long as the distance to the opposite shelf can be measured.

  In addition, the operation of the distance sensor is not limited to pressing of the manual operation buttons 14 and 15 and the traveling movement of the moving shelf, but may be a mode in which the distance sensor is always operated.

  The detection unit 11 does not necessarily include the transmission unit 12. For example, when the obstacle 18 is detected by the detection unit 11, the detection information may be displayed on the monitor 9. . Furthermore, the means for notifying the detection information may be a lighting lamp.

  Moreover, in the said Example, although the output value of distance sensor 2a-2c and distance sensor 3a-c was actually converted into the distance value corresponding to the distance between movement shelf 3A, 3B, respectively, it is not restricted to this. The output value of each distance sensor may be used as it is without being recognized and converted as the distance to the movable shelves 2A and 3A. Further, in the above-described embodiment, the mode in which the tolerance is set to 30 mm or more on the assumption that the ankle of a woman or a child is detected as an obstacle has been described. However, the detection of a small object such as a stepladder as an obstacle is assumed. In this case, the allowable error can be set to 20 mm or more, or the allowable error can be appropriately changed according to the size and shape of the articles stored in the shelf, the size, shape, and material of the shelf.

  Moreover, although sensor group (alpha), (beta), (gamma) demonstrated the case where the distance sensor of the opposing shelf was grouped, the sensor group may group only the distance sensor of one shelf. In this case, in the case of the article shelf device 4 shown in FIG. 2, the distance sensors 2a to 2c, the distance sensors 3a to 3c, the distance sensors 3d to 3f, the distance sensors 3g to 3i, the distance sensors 3j to 3m, and the distance sensors 2d to f. It consists of six sensor groups consisting of

  Moreover, although the mobile shelves 3A and 3B have been described with respect to an embodiment in which they are electric mobile shelves that are moved by the reversible motors 16 and 16, they may be moved manually, for example.

DESCRIPTION OF SYMBOLS 1 Obstacle detection apparatus 2A, 2B Fixed shelf 2a-2f Distance sensor (ultrasonic sensor)
3A, 3B Moving shelf 3a-3m Distance sensor (ultrasonic sensor)
4 article shelf device 11 detection part 12 transmission part (output part)
16 Reversible motor 17 Rotary encoder (inter-shelf distance measuring device)
18 Obstacles S1, S2 Work space α, β, γ Sensor group T1 Shelf distance t1 between fixed shelves 2A, 2B t2 Shelf distance t2 between fixed shelves 2A, moving shelves 3A Shelf between shelves 2B, movable shelves 3B Distance t3 Distance between shelves 3A, 3B between shelves W1 Shelf width W2 of shelves 3A Shelf width Z1 of shelves 3B Origin point Z2 of shelves 3A Origin point of shelves 3A

Claims (5)

An obstacle detection device for an article shelf device that detects an obstacle in a work space formed between movable shelves placed on rails,
A plurality of non-contact distance sensors installed between the shelves, an inter-shelf distance measuring device that determines a threshold corresponding to the distance between the shelves, and the thresholds and the outputs of all the distance sensors are compared. An obstacle detection device for an article shelf device, comprising: a detection unit.   The obstacle detection device for an article shelf device according to claim 1, wherein the inter-shelf distance measurement device determines the threshold value by measuring movement of the shelf.   The said detection part has an output part which transmits the signal which stops the drive part used for the movement of the said shelf based on the result of having compared the said threshold value and each output of all the said distance sensors. 3. An obstacle detection device for an article shelf device according to 1 and 2.   The detection unit detects that there is an obstacle in the work space when a difference between the threshold and an output of at least one distance sensor is 30 mm or more in terms of distance. An obstacle detection device for an article shelf device according to any one of the above.   The obstacle detection device for an article shelf device according to any one of claims 1 to 4, wherein the distance sensor is an ultrasonic sensor.

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