JPH0687308U - Optimal transfer position stop device for transport table of article storage system - Google Patents

Abstract

(57) [Summary] [Purpose] In an article storage system in which articles are transferred between a storage area of an article storage shelf and a transport table,
Providing a device that stops the transport table at the optimum transfer position. The stop device 20 includes a measuring unit 24 that measures a distance from a traveling base point position 53 of the transport table to a current position as the transport table 23 travels, and the transport table 23.
A pair of sensors 51 and 52 that are spaced apart from each other, a striker 55 that is provided in the storage area 30 and has a width narrower than the interval between the sensors, and the storage area 30 from the traveling base point position 53.
The control circuit 25 stores the distance up to as an absolute address and the sensor management area based on the absolute address. The transport table is controlled by the control circuit to have an absolute address as a target when traveling outside the sensor management area, and is made to travel independently of the absolute address when traveling inside the sensor management area, and the striker faces the pair of sensors. When stopped.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an article storage system having a transport table that travels along an article storage shelf having a plurality of storage areas and transfers articles to and from the storage area. The present invention relates to an apparatus for constantly stopping a transport table at an optimum transfer position where articles can be transferred smoothly between them.

[0002]

[Prior art]

 Conventionally, as an example of an article storage system (not shown), articles are transferred between an article storage shelf that has a plurality of storage areas for storing articles and a storage area that runs along the article storage shelf. And a measuring means (for example, a pulse encoder) for measuring the distance from the traveling base position of the conveying table to the storage area as the conveying table travels, and the value obtained in advance by this measuring means. There is one that moves the transport table to a designated storage area based on (absolute address, for example, the number of pulses).

Further, as another example of the article storage system, an article storage rack having a plurality of storage areas for storing articles and a transfer of the articles between the article storage shelves and the storage areas are performed. A transport table, a striker provided in each storage area and arranged in the traveling direction of the transport table, a sensor provided on the transport table for detecting strikers, and a counter for counting the number of strikers. Others find a storage area specified by the number of strikers to detect and stop the transport table. In this case, the transport table is decelerated when traveling to the striker in front of the designated storage area, and is stopped when the striker in the designated storage area is detected.

[0004]

However, in the former article storage system, the relative positional relationship between the article storage shelf and the delivery table is distorted due to deformation of the article storage shelf or the delivery table due to long-term use. If it occurs, there is a problem in that even if the transport table stops traveling based on the absolute address, it cannot be stopped at the optimum transfer position. As a method of coping with such a problem, it is conceivable to make the transport table learn and run every time the article storage system is used, or to re-store the absolute address. However, this method has another problem that it takes time to use the article storage system.

Further, in the latter article storage system, if the intervals between the strikers are not uniform, the deceleration stop control cannot be accurately performed, and the transport table cannot be stopped at a predetermined position. There is a problem.

[0006]

[Means for Solving the Problems]

 The first aspect of the present invention is to provide an article storage rack having a plurality of storage areas for storing articles, and a transfer table that travels along the article storage shelf and transfers the articles between the storage areas. In the article storage system having: a measuring means for measuring a distance from a traveling base point position of the transport table to a current position as the transport table travels; and a transport table separated from the transport table in a traveling direction of the transport table. The pair of sensors provided, the striker provided in the storage area and having a width narrower than the distance between the pair of sensors, and the distance from the traveling base position to the storage area are stored as an absolute address, and the absolute address is stored. The sensor control area based on the above is stored, the transport table is run, and one of the pair of sensors is stored in the storage area And a traveling control circuit that stops the transport table before the other of the striker is detected, and the transport table is controlled by the traveling control circuit when the vehicle travels outside the sensor management area. An optimum transfer position stopping device for the transport table that is driven with an absolute address as a target and is stopped without being driven regardless of the absolute address when traveling within the sensor management area, and secondly, storing articles. In the article storage system, there is provided an article storage rack having a plurality of storage areas, and a transportation table that travels along the article storage shelf to transfer the articles between the storage areas. Measuring means for measuring the distance from the traveling origin position of the transport table to the current position as the table travels; A pair of sensors spaced apart in the traveling direction of the cable, a striker provided in the storage area and wider than the distance between the pair of sensors, and the distance from the travel base point position to the storage area are absolute. In addition to storing the address, the sensor management area based on the absolute address is stored, the transport table is run, and the transport table is stopped when the pair of sensors simultaneously detect the striker in the designated storage area. The transport table is driven by the travel control circuit with the absolute address as a target when traveling outside the sensor management area, and when the travel table is traveling within the sensor management area, Can be moved and stopped regardless of the absolute address , The above-mentioned subject was solved.

[0007]

[Action]

 In the first article storage system, the worker causes the transport table to carry out learning travel in advance, stores the distance from the travel base position of the transport table to each storage area as an absolute address in the travel control circuit, and stores the absolute address. The reference sensor management area is also stored in the drive control circuit. The worker designates a storage area for loading and unloading articles. The travel control circuit causes the transport table to travel based on the comparison between the current position of the transport table measured by the measuring means and the absolute address, and when the transport table enters the sensor management area, it compares the current position with the absolute address. Run the transport table regardless. Finally, the travel control circuit stops the transport table before one of the pair of sensors passes the striker in the designated storage area and the other detects the striker. As a result, the transport table is stopped at the optimum transfer position for the designated storage area.

Also in the second article storage system, the worker performs a learning run on the transport table in advance, and stores the distance from the travel base point position of the transport table to each storage area in the travel control circuit as an absolute address. In addition, the travel control circuit also stores the sensor management area based on the absolute address. The worker designates a storage area for loading and unloading articles. The travel control circuit causes the transport table to travel based on the comparison between the current position of the transport table measured by the measuring means and the absolute address, and when the transport table enters the sensor management area, it compares the current position with the absolute address. Run the transport table regardless. Finally, the traveling control circuit stops the transport table when the pair of sensors simultaneously detect the striker in the designated storage area. As a result, the transport table is stopped at the optimum transfer position for the designated storage area.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS. The optimum transfer position stopping device 20 is incorporated in the article storage system 21 (see FIG. 1). First, the article storage system 21 (see FIG. 1) will be described. The article storage system 21 sorts and stores the articles W. The articles W are stored in the tray T as they are stored. The article storage system 21 is composed of an article storage shelf 22, a transport table 23, and the like. A well-known transfer device (not shown) is installed on the transport table 23 to transfer an article to and from a shelf plate 31 described later.

The article storage shelf 22 is a shelf having a plurality of storage areas 30 for storing articles in the vertical direction. The storage area 30 is partitioned by a shelf plate 31. The article storage shelf 22 is formed with an entry / exit port 32 for articles. A control box 33 is provided above the loading / unloading port 32.

The transport table 23 can be moved up and down by using the four columns 34, 34 (only two of them are shown in FIG. 1 as they overlap each other) as a guide. ing. The transport table 23 is connected to a chain 36 that is reciprocally reciprocated by a motor 35.

Next, the optimum transfer position stopping device 20 will be described. The optimum transfer position stopping device 20 has a relative positional relationship between the article storage rack 22 and the transport table 23 because the article storage rack 22 and the transport table 23 are deformed due to long-term use or the chain 36 extends. It is a kind of automatic control device that always decelerates the transport table 23 to the optimum transfer position with respect to the shelf board 31 and then stops the transport table 23 even if the error occurs.

The optimum transfer position stopping device 20 (see FIG. 2) includes a pulse encoder (measuring means) 24, a pair of optical sensors (sensors) 51 and 52, a base point striker 53 and 54, and a plurality of positioning strikers ( It is composed of a striker 55, a traveling control circuit 25, and the like. The pulse encoder 24 (see FIG. 2) is a known encoder that is connected to the motor 35 and performs pulse conversion of the rotation speed and rotation angle of the motor 35. The pair of optical sensors 51, 52 are transmissive optical sensors, and are provided on the side surface of the transport table 23 with a space in the vertical direction.

The base point strikers 53 and 54 (see FIGS. 1 and 2) are plate-shaped members that project from the upper and lower ends of the article storage shelf 22. The length (width) dimension L1 of the base point strikers 53, 54 (see FIG. 2) in the vertical direction is set wider than the distance L2 between the pair of optical sensors 51, 52. The position where the base point strikers 53 and 54 are provided becomes the traveling base point position of the transport table 23.

The positioning striker 55 is also a plate-shaped member protruding from the side surface of each shelf plate 31. As shown in FIG. 2, the length (width) dimension L3 of the positioning striker 55 in the vertical direction is set to be narrower than the interval L2 between the pair of optical sensors 51 and 52. Further, letting L4 (see FIG. 5) be the allowable step difference in the vertical direction that allows smooth transfer of articles between the shelf plate 31 and the transport table 23, the relationship of (L4 = L2-L3) It is in.

The traveling control circuit 25 (see FIG. 8) is housed in the control box 33 (see FIG. 1). The traveling control circuit 25 includes an addition / subtraction counter 60, a target value storage unit 61, a current position calculation unit 62, a command unit 63, a lifting speed control unit 64, and a sensor operation state detection unit 65.

The addition / subtraction counter 60 is a counter that counts the pulses from the pulse encoder 24. That is, the addition / subtraction counter 60 is configured to add the pulse number when the transport table 23 rises and subtract the pulse number when the transport table 23 descends.

The target value storage unit 61 stores the stop position of the transport table 23 for each shelf plate 31, that is, for each storage area 30 from the travel base point position of the transport table 23 obtained by learning travel of the transport table 23 described later. It is a circuit that stores the distance to as an absolute address.

The current position calculation unit 62 is a circuit that calculates how far the transport table 23 is from the shelf plate 31 of the designated storage area 30. Therefore, when the transport table 23 travels to the designated storage area 30, the current position calculation unit 62 calculates "0".

The command unit 63 sends a storage command signal P 1 for storing the absolute address of each shelf 31 to the target value storage unit 61 when the transport table 23 is running, and further, the absolute value stored in the target value storage unit 61. It is a circuit for sending a calling signal P2 for calling an address to the target value storage unit 61. Further, the command unit 63 sends up / down command signals P3 and P4 for designating the ascending / descending direction of the carrying table 23 and a speed command signal P10 for controlling the ascending / descending speed of the carrying table 23 to the ascending / descending speed control unit 64, Further, it is also a circuit that sends a reset signal P5 that clears the addition / subtraction counter 60 to "0" at the start of learning traveling of the transport table 23. The command unit 63 stores in advance a pulse number ZB corresponding to the sensor management region (see FIG. 9), a pulse number ZC corresponding to the low speed region, and a pulse number ZD corresponding to the deceleration region.

The sensor operation state detection unit 65 is a circuit that informs the command unit 63 whether the pair of optical sensors 51, 52 detect the base striker 53, 54 or the positioning striker 55.

Next, the operation will be described. First, the learning travel of the transport table 23, which stores the optimum transfer position of the transport table 23 with respect to each shelf 31, will be described. The worker pushes a teaching button (not shown) on the control box 33. The command unit 63 sends the descending command signal P4 to the ascending / descending speed control unit 64 and sends the storage command signal P1 to the target value storage unit 61. The ascending / descending speed control unit 64 operates the motor 35 so that the transport table 23 descends.

When the transport table 23 is lowered to the lower end of the article storage shelf 22, the pair of optical sensors 51 and 52 detect the base striker 53 by blocking the light from the base striker 53. Since the vertical dimension L1 (see FIGS. 1 and 2) of the base point striker 53 is set to be wider than the interval L2 between the pair of optical sensors 51 and 52, the pair of optical sensors 51 and 52 are simultaneously set to the base point. The striker 53 is detected. The sensor operating state detection unit 65 (see FIG. 8) informs the command unit 63 that the pair of optical sensors 51, 52 have detected the base striker 53. The command unit 63 sends the reset signal P5 to the addition / subtraction counter 60 to set the value of the addition / subtraction counter 60 to "0". Further, the command unit 63 sends a lift command signal P3 to the lifting speed control unit 64 to lift the transport table 23.

The motor 35 raises the transport table 23. The rotation of the motor 35 operates the pulse encoder 24. The addition / subtraction counter 60 starts addition counting of the pulses sent from the pulse encoder 24. When the transport table 23 rises and the optical sensor 51 on the upper side detects the positioning striker 55 provided near the shelf 31 of the first stage (see FIG. 4), the sensor operating state detection unit 65 (see FIG. 8). ), The detection signal P6 is sent to the command unit 63.

The command unit 63 stores the pulse number Z 1A = (Z1 + ZA) obtained by adding the correction pulse number ZA to the pulse number Z1 at that time in the target value storage unit 61 as an absolute address. As a result, the absolute address of the first-stage shelf board 31 is stored in the target value storage unit 61. The correction pulse number ZA is set to a distance L5 that raises the transport table 23 from the solid line state in FIG. 6 to the image line state so that the positioning striker 55 is located at the center between the pair of optical sensors 51 and 52. This is the corresponding number of pulses. In the example, L5 is equal to L4.

After that, the transport table 23 continues to move upward, and the upper optical sensor 51 detects the positioning striker 55 of the second-stage shelf plate 31. The target value storage unit 61 stores the correction pulse number in the pulse number Z2 from the base striker 53 to the positioning striker 55 of the second shelf 31 as in the case of storing the absolute address of the first shelf 31. The pulse number Z2A added with ZA is stored as the absolute address of the shelf plate 31 of the second stage.

In the same manner, the pulse number (ZNA, see FIG. 9) of the shelf plate 31 of each stage is stored as an absolute address. The absolute address of the shelf board 31 is also the absolute address of the storage area 30. Finally, when the pair of sensors 51 and 52 detect the base striker 54 at the same time, the sensor operating state detection unit 65 notifies the command unit 63 of the fact. The command unit 63 sends a motor stop signal for stopping the motor 35 to the ascending / descending speed control unit 64, and also sends a learning completion signal to the target value storage unit 61. The absolute address may be stored by using the base point striker 54 provided at the upper end of the article storage rack 22 as the traveling base point position.

Next, the operation of loading the article into the desired storage area 30 from the transport table 23 will be described. The operator designates the desired storage area 30 by the control box 33 (see FIG. 1). The command unit 63 (see FIG. 8) sends a calling signal P2 to the target value storage unit 61 in order to call the absolute address of the designated storage area 30. The target value storage unit 61 calls the absolute address of the desired storage area 30 in response to the calling signal P2 and notifies the current position calculation unit 62 of the absolute address. On the other hand, the current position calculation unit 62 is sent from the addition / subtraction counter 60 the number of pulses at the current position of the transport table 23. The current position calculation unit 62 subtracts the number of pulses at the current position of the transport table 23 from the absolute address, obtains the difference, and sends the value to the command unit 43.

The difference has a positive value, a negative value, and a value of “0”. When the difference is a positive value, it means that the transport table 23 is below the designated storage area 30. Therefore, the command unit 63 sends the ascending / descending speed control unit 64 the raising command signal P3 for raising the transport table 23. send. Conversely, when the difference is a negative value, it means that the transport table 23 is above the designated storage area 30. Therefore, the command unit 63 instructs the ascending / descending speed control unit 64 to lower the transport table 23. Send signal P4. Further, when the difference is “0”, it means that the transport table 23 is stopped at the designated storage area 30, so the command unit 63 does not send a signal to the ascending / descending speed control unit 64, and the transport table A transfer control signal is sent to another transfer control circuit (not shown) so that the article can be carried in from 23 to the shelf 31 of the storage area 30.

The ascending / descending speed control unit 64 controls the motor 35 so as to raise or lower the transport table 23 according to the ascending / descending command signals P3, P4 from the command unit 63. When the difference between the count value of the addition / subtraction counter 60 and the absolute address of the designated storage area 30 becomes less than the pulse number ZD (see FIG. 9) of the deceleration area as the transport table 23 moves up and down, the command unit 63 A speed command signal P10 is sent to the ascending / descending speed control section 64 to cause the transport table 23 to run at a middle speed, and the transport table 23 is run at a middle speed. Further, when the difference between the count value of the addition / subtraction counter 60 and the absolute address of the designated storage area 30 becomes equal to or less than the pulse number ZC in the low speed area, the command unit 63 raises / lowers the speed command signal P10 to cause the transport table 23 to travel at low speed. It is sent to the speed control unit 64 and the transport table 23 is run at a low speed.

When the difference between the count value of the addition / subtraction counter 60 and the absolute address of the designated storage area 30 becomes equal to or less than the pulse number ZB of the sensor management area, the command unit 63 causes the difference between the counter value and the absolute address. Irrespective of the above, when a sensor detection signal P6 or P7 is received from the sensor operating state detection unit 65 that one of the pair of sensors 51, 52 has passed the striker, the stop signal is raised or lowered to stop the transport table 23. The transportation table 23 is sent to the speed control unit 64 and the transport table 23 is stopped. As a result, the transport table 23 is stopped at the optimum transfer / transfer position where the positioning striker 55 is opposed between the pair of sensors 51, 52.

If the inertia of the transport table causes one of the pair of sensors to pass the positioning striker and the other to face the positioning striker so that the transport table stops, the command unit 63 returns the transport table. Let it run. Also in this case, the transport table 23 is stopped at the optimum transfer position with the positioning striker 55 facing the pair of sensors 51 and 52. As a result, the transport table 23 is brought into a state in which articles can be carried in between the transport table 23 and the shelf board 31.

When carrying out a desired article from the storage area, the same operation as when carrying in the article is performed.

Next, an optimum transfer position stopping device 120 of another embodiment will be described with reference to FIGS. 10 to 13. The parts other than the pair of optical sensors 151, 152, the positioning striker 155, and the base point strikers 153, 154 are the same as the structure shown in FIGS. 1 to 8, and therefore the description of the structure will be omitted.

The base point strikers 153 and 154 (see FIG. 10) are plate-shaped members protruding from the upper and lower ends of the article storage shelf 22. The length (width) dimension L11 of the base point strikers 153 and 154 in the vertical direction is set to be narrower than the distance between the pair of optical sensors 151 and 152. For this reason, the value of the addition / subtraction counter is reset to “0” when the base strikers 153 and 154 face each other between the pair of optical sensors 151 and 152 during the learning traveling of the transport table 23.

The positioning striker 155 is also a plate-shaped member protruding from the side surface of each shelf plate 31. The length (width) dimension L13 of the positioning striker 155 in the vertical direction is set to be wider than the interval L12 between the pair of optical sensors 151 and 152, as shown in FIG. Further, assuming that the allowable vertical step size for smoothly transferring the article between the shelf plate 31 and the transport table 23 is L14 (see FIG. 12), there is a relationship of (L13 = L12 + L14).

The absolute address of each storage area 30 is the pulse number obtained by adding the correction pulse number to the pulse number when the pair of optical sensors 151 and 152 detect the positioning striker 155 when the transport table 23 is raised. . The number of correction pulses is from the time when the pair of optical sensors 151 and 152 detect the positioning striker 155 until the center between the pair of optical sensors 151 and 152 and the vertical center of the positioning striker 155 coincide. Is the number of pulses corresponding to the distance L15 (see FIG. 13). Note that there is a relationship of L15 = (L14 / 2).

Also in this optimum transfer position stopping device 120, the transport table 23 moves up and down to the designated storage area 30, enters the sensor management area, and the pair of optical sensors 151 and 152 oppose the positioning striker 155. The transport table 23 is stopped when it is shielded from light. As a result, the transport table 23 is stopped at the optimum transfer / transfer position where the pair of sensors 51, 52 are opposed to the positioning striker 55.

If one of the pair of sensors comes off the positioning striker due to inertia of the transport table and the transport table stops, the command unit 63 causes the transport table to return and run. Even in this case, the transport table 23 stops the pair of sensors 51 and 52 at the optimum transfer position with the pair of sensors 51 and 52 facing the positioning striker 55.

In this way, the optimum transfer position stopping devices 20 and 120 are distorted in the relative positional relationship between the article storage shelf 22 and the transport table 23 due to the distortion of the article storage shelf 22, the elongation of the chain 36, and the like. Even if the reliability of the absolute address stored by the learned travel of the transport table 23 decreases, just before stopping the transport table 23, the strikers 55, 155 and the pair of sensors 51 are irrelevant regardless of the absolute address. , 52, 151, 152 relative to each other, the transport table can always be stopped at the optimum transfer position.

The optimum transfer position stop devices 20 and 120 not only control the stop of the transport table that moves up and down along the article storage shelf having the storage area in the vertical direction, but also store the article storage shelf having the storage area in the horizontal direction. It is also possible to perform stop control of a transport table (for example, a stacker crane) that travels left and right along (not shown).

[0042]

[Effect of device]

 According to the optimum transfer position stopping device of claims 1 and 2, even if the relative positional relationship between the article storage rack and the transport table is deviated, and the reliability of the absolute address stored by the learning traveling of the transport table is lowered, When the transport table is about to be stopped, it is stopped by the relative positional relationship between the striker and the pair of sensors regardless of the absolute address, so that the transport table can always be stopped at the optimum transfer position.

[Brief description of drawings]

FIG. 1 is a front view of an article storage system including an optimum transfer position stopping device of the present invention.

FIG. 2 is a schematic diagram showing a pair of optical sensors, a base striker, and a positioning striker.

3 is a partially enlarged view of a pair of optical sensors and a positioning striker of FIG.

FIG. 4 is an enlarged view of a pair of optical sensors and a positioning striker.

FIG. 5 is a diagram showing a positional relationship between a pair of optical sensors and a positioning striker.

FIG. 6 is a diagram showing a positional relationship between a pair of optical sensors and a positioning striker.

FIG. 7 is a diagram showing a positional relationship between a pair of optical sensors and a positioning striker.

FIG. 8 is a block diagram of a travel control circuit.

FIG. 9 is a diagram showing a sensor management area centering on a positioning striker.

FIG. 10 is a front view of an article storage system including an optimum transfer position stopping device according to another embodiment.

11 is a diagram showing a positional relationship between a pair of optical sensors and a positioning striker of the optimum transfer position stopping device in FIG.

FIG. 12 is a diagram showing a positional relationship between a pair of optical sensors and a positioning striker of the optimum transfer position stopping device in FIG.

13 is a diagram showing a positional relationship between a pair of optical sensors and a positioning striker of the optimum transfer position stopping device in FIG.

[Explanation of symbols]

W Articles L2, L12 Distance between optical sensors (sensors) L3, L13 Width of positioning striker (strike) 20, 120 Optimal transfer position stop device 21 Article storage system 22 Article storage rack 23 Transport table 24 Pulse encoder (measuring means) 25 Travel control circuit 30 Storage area 51, 52, 151, 152 Optical sensor (sensor) 53, 54, 153, 154 Base point striker (running base point position) 55, 155 Positioning striker (strike)

Claims (2)

[Scope of utility model registration request] 1. An article comprising: an article storage shelf having a plurality of storage areas for storing articles; and a transport table that travels along the article storage shelf and transfers the articles to and from the storage area. In the storage system, a measuring unit that measures a distance from a traveling base point position of the transport table to a current position as the transport table travels, and a pair provided on the transport table so as to be separated from each other in the traveling direction of the transport table. Sensor, a striker having a width narrower than the distance between the pair of sensors provided in the storage area, and storing the distance from the traveling base point position to the storage area as an absolute address, and a sensor based on the absolute address. The management area is stored, the transport table is run, and one of the pair of sensors passes a striker in a designated storage area. , The other has a travel control circuit that stops the transport table before detecting the striker, the transport table, by the travel control circuit, the absolute address as a target when traveling outside the sensor management area. An optimum transfer position stopping device for a transfer table of an article storage system, wherein the optimum transfer position stopping device is configured to be driven independently of the absolute address and stopped when traveling in the sensor management area. 2. An article having an article storage shelf having a plurality of storage areas for storing articles, and a transport table which runs along the article storage shelf and transfers the articles to and from the storage area. In the storage system, a measuring unit that measures a distance from a traveling base point position of the transport table to a current position as the transport table travels, and a pair provided on the transport table so as to be separated from each other in the traveling direction of the transport table. And a striker having a width wider than the distance between the pair of sensors provided in the storage area, and storing the distance from the traveling base position to the storage area as an absolute address, and a sensor based on the absolute address. The management area is stored, the transport table is run, and the pair of sensors simultaneously detect strikers in the designated storage area. And a travel control circuit that stops the transport table when the travel table is used, the transport table is driven by the travel control circuit with the absolute address as a target when traveling outside the sensor management area,
An optimum transfer position stopping device for a transport table of an article storage system, characterized in that when the vehicle travels in the sensor management area, it is driven and stopped independently of the absolute address.