JP2006315795A - Automatic centering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic centering device capable of easily matching the center line of an article with the basic position, regardless of size of articles, and stopping it. <P>SOLUTION: This automatic centering device for conveying an article having a front end and a rear end in the conveying direction at a fixed speed and for matching the center line of the front end and the rear end with the basic position, which is set on the way in the conveying direction, for positioning is provided with a conveying device for conveying the article in the conveying direction, a detecting sensor for detecting the front end or the rear end of the article to output a detecting signal in a process for conveying the article with the conveying device, a movable stopper arranged at the basic position for positioning the front end of the article, and a moving means for moving the movable stopper in the conveying direction at half the article conveying speed. When the detecting sensor detects the rear end of the article, the moving means stops movement of the movable stopper in the conveying direction at the same time. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an apparatus for easily centering an article to be transported on a transport apparatus such as a conveyor, and a simple centering method.

When storing goods in a warehouse, a roll transport device that often moves a forklift, a stacker crane, or a roll-shaped product sandwiched from both sides of the product that has been transported to a predetermined position by a transport device such as a conveyor. May be transported to other places using

In such a case, it is preferable that the article on the transport device is surely stopped at a position optimal for pickup as viewed from the forklift or the like. In the transport direction of the transport device, the position on the transport device to be stopped by matching the center lines of the front end and the rear end of the article is hereinafter referred to as “
It is referred to as a “basic position” and, for example, exists on the center line (bisector) of two forks in front of the forklift. Further, a center line (a bisector between the front end and the rear end) that bisects between the front end and the rear end of the article is referred to as an “article center line”, and a “center line between the front end and the rear end” of the article. It is synonymous with.

Conventionally, in order to stop the article by aligning the center line of the article with the basic position of the transport device, the following method has been generally employed (see FIG. 9). Hereinafter, for the sake of simplicity, a description will be given using a belt conveyor as shown in FIG.

(1) The article 30 is stopped by hitting the measurement end 140. (2) The length of the article 30 is measured using a length measuring device (not shown). (3) The stop end 141 is moved so that the center line of the article coincides with the basic position and stops, calculated from the measured value of (2). (4) The article 30 is stopped by hitting the stop end 141.

In FIG. 9, the conveyor 1001 includes a starting end roller 20 and a terminating end roller 21,
The endless belt 10 is stretched between the rollers 20 and 21, and the measurement end 140 and the stop end 141 are disposed above the belt 10. The article 30 is conveyed on the belt 10 from the start end roller 20 side toward the end end roller 21 with its front end directed toward the end end roller 21. Hereinafter, the direction will be described as the transport direction.

Conventionally, for example, the center of the article 30 is stopped according to the basic position on the conveyor 1001 by the above-described method. However, when the above-described method is adopted, a device related to length measurement such as the measuring end 140 or the length measuring device is expensive.

Further, in order to measure the length of the article 30, it is necessary to stop the article 30 by the measuring end 140 and the conveyor 1001 on which the article 30 is placed once. For this reason, time is lost in the measurement of the said article | item 30, and the cycle time which conveys the article | item 30 becomes long.

Japanese Utility Model Publication No. 54-84784

In order to solve such an inconvenience, Patent Document 1 discloses the following device. That is, the device of Patent Document 1 relates to a device that stops the center line of an article having a specific length (Lmin) in accordance with the basic position, and also when the length of the article being conveyed is longer than the specific length (Lmin). This is an automatic positioning device that can automatically stop by aligning the center line of the article with the basic position. This automatic positioning device arranges a detector at a predetermined position on the start roller side from the basic position of the conveyor, and a stopper at a closest position (Lmin / 2) on the end roller side from the basic position. When the time-up time (a specific time depending on the specific length Lmin) has elapsed since the front edge of the article on the roller has been detected, the stopper is retracted at half the article transport speed, and the detector An automatic positioning apparatus is disclosed in which the stopper is moved to a position where the center line of the article can be stopped at the basic position at the same time when the rear end is detected. In addition, “the detector detects the rear end of the article on the roller” is synonymous with the fact that the article becomes detectable but cannot be detected,
The same applies hereinafter.

However, the automatic positioning device of Patent Document 1 is premised on the conveyance of an article having a specific length Lmin. When a longer article is conveyed based on the length Lmin, the stopper is moved to place the article in place. Just stop. Therefore, the specific length Lmin of the article that is the reference for the conveyance
Therefore, it is necessary to reset the time-up time and the closest approach position (Lmin / 2).

Moreover, since the stopper of the above-mentioned patent document 1 is arranged at a predetermined distance (Lmin / 2) away from the basic position of the conveyor in the conveying direction from the beginning, articles smaller than the predetermined distance are stopped at a desired position. I can't. That is, it cannot respond to an article having a length less than a specific length (Lmin).

In view of the above problems, the present invention can stop the article by aligning the center line of the article with the basic position of the conveyor (hereinafter referred to as “centering”) by a simple method regardless of the size of the article. An automatic centering device for articles is provided.

The automatic centering device according to the present invention conveys an article having a front end and a rear end at a constant speed with the front end directed in the transport direction, and the front end and the rear end at a basic position set in the middle of the transport direction. An automatic centering device for positioning the article so as to match a center line with a conveying device that conveys the article in the conveying direction, and a step of conveying the article by the conveying device, and a front end of the article Thru | or the detection sensor which detects a rear end and sends out a detection signal, the movable stopper which is arrange | positioned in the said basic position and can position the front end of the said article | item, and the said article is conveyed by the said movable stopper based on the said detection signal Moving means for moving in the transport direction at half the speed, and the moving means detects the front end of the article at the same time as the detection sensor detects the front end of the article. To start moving in the feeding direction, at the same time when the sensor detects the rear end of the article, you may move the stops to the conveying direction of the movable stopper.

In the automatic centering device of the present invention, the transport device may stop transport simultaneously with the movable stopper contacting the front end of the article.

The automatic centering device of the present invention is the above-described automatic centering device including a first encoder that detects the transport speed of the transport device, wherein the moving means is half the transport speed detected by the first encoder. The movable stopper may be moved in the transport direction.

The automatic centering device of the present invention can stop an article to be conveyed at a desired position of the conveying device without using a length measuring device. Therefore, the present invention can provide a transport apparatus capable of performing the centering as an inexpensive system.

By using the automatic centering method of the present invention, unlike the conventional centering method, it is not necessary to stop the article once by the measuring end and the conveying device on which the article is placed, and the time required for length measurement can be saved. Therefore, the present invention can provide a smooth system in which the transport cycle time is reduced.

Further, in the automatic centering device of the present invention, the movable stopper is not disposed at a predetermined distance from the basic position of the transport device, unlike the centering device of Patent Document 1, and is disposed immediately above the basic position. Therefore, even a small article does not contact the movable stopper beyond the basic position, and the article can be stopped by aligning the center line and the basic position of the article by a simple method regardless of the size of the article. it can.

  Hereinafter, an embodiment of the present invention will be described with reference to FIG.

The automatic centering device 1 of the present invention conveys an article 30 having a front end and a rear end at a constant speed with the front end of the article 30 toward the front in the carrying direction, and at a basic position set in the middle of the carrying direction. This is an apparatus for positioning the article 30 in a state in which the center line that bisects the front end and the rear end of the 30 is matched.

Then, the automatic centering device 1 of the present invention detects between the conveying device 5 that conveys the article 30 in the conveying direction and the front end and the rear end of the article 30 in the process of conveying the article 30 by the conveying device 5. A detection sensor 50 that sends a detection signal and a movable stopper 40 that is disposed at the basic position and can position the front end of the article 30 are included. Further, the automatic centering device 1 includes a moving means 41 that moves the movable stopper 40 in the transport direction at a speed that is half the speed at which the article 30 is transported based on the detection signal sent from the detection sensor 50.

In this embodiment, the conveying device 5 is a belt-type conveyor, and includes a start end roller 20 and a terminal end roller 21, a belt 10 stretched between the rollers 20 and 21, and a roller driving device (not shown). The The roller driving device drives the start end roller 20 and / or the end roller 21 to drive the belt 10 from the start end roller 20 toward the end roller 21. Hereinafter, this direction is defined as “transport direction”. In the present invention, the conveying device is not limited to a belt type conveyor, and all the conveyor type conveying devices 5 such as a roller conveyor and a chain conveyor are included in the automatic centering device of the present invention. Further, as shown in FIG. 1, the transport device 5 may be used by connecting a plurality of transport devices 5 in series or in parallel.

The article 30 is, for example, a paper roll or the like, and is conveyed on the belt 10 in the conveyance direction with the front end thereof directed toward the end roller 21. In the present embodiment, the length in the conveyance direction of the article 30 is 1 and the distance between the start end roller 20 and the end end roller 21 is L.

The basic position refers to a virtual position on the transport device 5 that should be stopped by matching a center line that bisects the front end and the rear end of the article 30 in the transport direction of the transport device 5. Is a position where the belt 10 of the conveying device 5 intersects. In this embodiment, the basic position is a position d away from the starting end roller 20 in the transport direction.

The detection sensor 50 is installed at the position of the starting end roller 20 in the present embodiment, and the belt 1
The article 30 conveyed on 0 is detected. The detection sensor 50 is preferably installed on the ceiling, floor, stay, or the like, and is set at a right angle to the transport direction. The detection sensor 50 may be any sensor that can detect an article, such as a proximity sensor, an infrared sensor, or an ultrasonic sensor, and is not particularly limited.

The movable stopper 40 is disposed above the belt 10 and is set so that a stop surface 401 that is a front surface of the movable stopper 40 that stops the article 30 is directly above the basic position. In this embodiment, the movable stopper 40 can be advanced and retracted by the moving means 41, and the article 30
And a pressure sensor 42 for detecting the presence or absence of contact.

The moving means 41 is, for example, a hydraulic cylinder in which a cylinder body is fixed to the transport device 5.
A movable stopper 40 is attached to the tip of a movable rod extending from the cylinder body. The moving means 41 is not particularly limited to a hydraulic cylinder, and an electric actuator is more preferably used when accurate positioning of the movable stopper 40 is required. In addition, the moving means 41 includes all means for moving the movable stopper 40 forward and backward with respect to the transport direction.

Next, the operation of the automatic centering device 1 of the present invention will be described with reference to FIGS.

(1) In FIG. 2A, the transport device 5 transports the article 30 at a constant speed v in the transport direction. The movable stopper 40 is disposed such that a stop surface 401 for stopping the article 30 is directly above the basic position. In the state of FIG. 2A, since the detection sensor 50 has not detected the article 30, the movable stopper 40 is stationary at the above position. 2A to 2E, the basic position is a position where the two-point difference line and the belt 10 cross each other at a distance d from the starting end roller 20 in the transport direction.

(2) The state of FIG. 2B shows the moment when the detection sensor 50 detects the front end of the article 30. The instantaneous detection sensor 50 sends a detection signal to the CPU 70 shown in FIG. 3, for example. The CPU 70 that has received the detection signal immediately sends an operation start signal to the moving means 41, but in this state, the movable stopper 40 is stationary.

(3) In the state of FIG. 2C, the detection sensor 50 detects between the front end and the rear end of the article 30. As described above, the detection sensor 50 sends a detection signal to the CPU 70 shown in FIG. 3, for example. 3 that has received the detection signal sends an operation signal to the moving means 41, and the moving means 41 moves the movable stopper 40 in the transport direction at a speed of v / 2.

(4) FIG. 2D shows the article 3 after Δt after the detection sensor 50 detects the front end of the article 30.
The state at the moment when the rear end of 0 is detected is shown. From this next moment, the detection sensor 50 no longer detects the article 30, and the CPU 70 determines the rear end of the article 30. The CPU 70 stops sending an operation signal to the moving means 41 or sends a stop signal so that the moving means 41 can move the movable stopper 4.
Stop moving 0. However, even after the movable stopper 40 is stopped, the transport device 5 remains in the article 3
Continue to convey 0 as it is at the speed v.

(5) In FIG.2 (e), the front end of the articles | goods 30 which continued being conveyed by the conveying apparatus 5 contacts the stop surface 401 of the movable stopper 40, and between the front ends and rear ends is demonstrated as demonstrated below. Stop with the equally divided center line aligned with the basic position. The pressure sensor 42 of the movable stopper 40 in contact with the article 30 sends a contact signal to the CPU 70, the CPU 70 stops the roller driving device 60, and the conveying device 5 stops conveying. In addition, the continuous conveyance apparatus may continue conveyance.

Hereinafter, the reason why the automatic centering device 1 of the present invention can be stopped in a state where the center line between the front end and the rear end of the article 30 matches the basic position by the above steps (1) to (5). To do.

When the detection sensor 50 detects the front end of the article 30 in the step (2) (see FIG. 2B), the moving means 41 moves the movable stopper 40 in the transport direction at a speed of v / 2. Then, after Δt, in step (4) (see FIG. 2D), the detection sensor 50 detects the rear end of the article 30, and the moving means 41 stops the movement of the movable stopper 40. Therefore, the movable stopper 40 moves in the transport direction from the basic position by a total of (v / 2) × Δt.

As described above, Δt is the time from when the detection sensor 50 detects the front end of the article 30 until the rear end of the article 30 is detected. During this time, the process (3) (see FIG. 2C) is performed. As shown
Since the article 30 moves in the conveyance direction at a speed v, it moves by v × Δt, and this distance is equal to the length l between the front end and the rear end of the article 30. Therefore, v × Δt = 1 is established.

Therefore, the stop surface 401 of the movable stopper 40 stops at a position moved in the transport direction from the basic position by (v / 2) × Δt = 1/2.

On the other hand, the article 30 continues to move in the transport direction at the speed v even after the above Δt has elapsed, that is, after the movable stopper 40 stops, and stops in contact with the stop surface 401. Therefore, since the front end of the article 30 stops at a position 1/2 in the conveyance direction from the basic position, the article 30 stops in a state where the center line between the front end and the rear end matches the basic position.

As described above, the automatic centering device 1 of the present invention detects the article 30 to be conveyed by the detection sensor 5.
Only while 0 is detected, the movable stopper 40 is retracted from the basic position at half the conveying speed of the article. Therefore, like the apparatus of Patent Document 1, centering can be performed without having to change the setting of the apparatus depending on the specific length of the conveyed article.

However, in the above description, the article 30 moves without contacting the movable stopper 40 during the time from when the detection sensor 50 detects the front end of the article 30 until the rear end of the article 30 is detected, that is, Δt. Is the premise. Therefore, hereinafter, a condition in which the article 30 does not contact the movable stopper 40 during the time Δt is obtained.

The time for the detection sensor 50 to detect the front end of the article 30 is t = 0, and the article 30 is the movable stopper 4.
If the time of contact with 0 is t = t1, a condition satisfying t1 ≧ Δt may be obtained.

When t = t1 (≧ Δt), the movable stopper 40 is at a position of (v / 2) × Δt = 1/2 in the transport direction from the basic position as described above. On the other hand, the article 30 is between t1 and v × t1 = d +
It is conveyed by 1/2 and contacts the movable stopper 40. Here, d is the distance between the basic position and the detection sensor 50 as described above.

From the above two formulas, it can be seen that d ≧ l / 2 is necessary to satisfy t1 ≧ Δt.
That is, in order for the centering of the article 30 having the length l by the automatic centering apparatus 1 of the present invention to be effective, the distance d between the basic position and the detection sensor 50 needs to be larger than half the length l of the article 30. However, the transport device 5 includes a normal transport article 30 including a case where a plurality of transport devices are connected.
Since it is sufficiently long, it is generally possible to install the detection sensor 50 far from the basic position compared to the length of the article 30.

When the above condition is interpreted in reverse, the centering method of the article 30 by the automatic centering device 1 of the present invention is effective no matter how short the article 30 is. That is, the automatic centering device 1 of the present invention can stop the article by aligning the center line and the basic position of the article by a simple method regardless of the size of the article 30.

For example, the distance d between the basic position and the detection sensor 50 is greater than half of the length l of the article 30, and the length L of the transport device 5 (including the case where a plurality of transport devices are connected) is overwhelming than the distance d. Consider a large case. That is, in the first embodiment, l / 2 ≦ d << L is established. The cross section of the automatic centering device 1 of the first embodiment under such conditions can be schematically represented as shown in FIG. The same reference numerals as those in the above embodiment are used.

A basic position at which a transport device such as a forklift that picks up the article 30 is advantageous for the pick-up is represented by an intersection of the transport device 5 and a dotted line in FIG. In FIG. 4, the function and operation of each component are the same as in the above embodiment.

Therefore, the steps (1) to (5) of the above embodiment are the article 30 and the movable stopper 40 of this example.
The detection sensor 50 and the transfer device 5 are also established as they are. That is, the detection sensor 50 can be installed at an arbitrary position where d ≧ l / 2 from an arbitrary basic position. Even if the article 30 has a sufficiently short length in the carrying direction compared to the length of the carrying device 5, the automatic centering device 1 according to the present invention stops the article 30 by aligning the center line with the basic position of the article 30. Can do.

Examples of the present invention will be described below. In addition, the same code | symbol is used for the component same as the said embodiment. Further, in FIG. 5 and subsequent drawings according to each embodiment, the conveyance direction of the articles is changed from the left direction to the right direction.

6A and 6B are a plan view and a cross-sectional view of the transfer device 5 of the present embodiment. In this embodiment, the conveying device 5 is a roller type conveyor 5, and the moving means 41 is a hydraulic cylinder 41.
The total length of the conveyor 5 is L = 2635 mm.

The basic position is a position d = 2005 mm away from the starting end of the conveyor 5 in the transport direction. In the state before the start of centering shown in FIGS. 6A and 6B, the stop surface 401 that is the front surface of the movable stopper 40 is Located directly above. Other configurations are the same as those in the above-described embodiment, and are omitted.

5 (a) to 5 (e) show an article 30 having a length l = 1060mm in the conveying direction at a speed v = 10 (
(m / min) shows the state of centering when transported. When the detection sensor 50 detects the front end of the article 30 in FIG. 5B, the movable stopper 40 starts moving in the transport direction.
While the detection sensor 50 detects between the front end and the rear end of the article 30, as shown in FIG. 5C, the hydraulic cylinder 41 moves the movable stopper 40 at a speed v / 2 = 5 (m / min). Move in the transport direction.

FIG. 5D shows a state in which the rear end of the article 30 is detected after Δt = 6.36 seconds after the detection sensor 50 detects the front end of the article 30. Stop surface 401 is 530 from the basic position.
Although it stops at mm (= l / 2), the transport device 5 continues to transport the article 30 as it is at a speed v = 10 (m / min).

15.21 seconds after the detection sensor 50 detects the front end of the article 30, the front end of the article 30 contacts the stop surface 401 as shown in FIG. Article 30 is
Stop in a state where the center line that bisects the front end and the rear end matches the basic position.

  Other operations are the same as those in the above embodiment, and will be omitted.

The automatic centering device 1 of the present embodiment performs centering when the transport speed of the transport device 5 changes.

FIG. 7 is a plan view of the transport device 5 of the present embodiment. In the transport apparatus, that is, the conveyor 5 of this embodiment, a first encoder 80 and a second encoder 82, which are encoders for speed detection, are installed on the side of the conveyor 5 body and the moving means 41. The first encoder 80 detects the speed of the conveyor 5, and the second encoder 82 detects the speed of the moving means 41, that is, the speed of the movable stopper 40.

In this embodiment, since the movable stopper 40 needs to be accurately positioned, the moving means 4
It is more preferable to use an electric actuator as 1. In addition, the other structure of the automatic centering apparatus 1 of a present Example is the same as that of the said embodiment and Example 1. FIG.

The automatic centering device 1 of the present example is similar to the above embodiment and example 1 in that the article 30
While passing through the detection sensor 50, the moving means 41 pulls the movable stopper 40 in synchronization with the movement of the conveyor 5. However, at this time, the encoder 80 detects the speed of the conveyor 5 and the moving means 41 pulls the movable stopper 40 at half the speed. That is, unlike the above embodiment, the automatic centering device 1 of this embodiment can perform centering in response to the speed change even if the speed of the conveyor 5 (article 30) changes.

The operation of the automatic centering apparatus 1 of this embodiment will be described below with reference to the flow chart 8. still,
The speed of the conveyor 5 (article 30) is v (t), and the speed of the movable stopper 40 (moving means 41) is v '(t) / 2.

(S1) The first encoder 80 detects the speed v (t) of the conveyor 5 and sends it to the CPU 70.

(S2) The CPU 70 calculates the standard moving speed v (t) / 2 of the movable stopper 40 from v (t).

(S3) The second encoder 82 moves the actual moving speed v ′ (
t) / 2 is detected and sent to the CPU 70.

(S4) The CPU 70 compares the standard moving speed v (t) / 2 and the actual moving speed v ′ (t) / 2. If they are equal, the process proceeds to s1 (maintains the speed of the movable stopper 40), and if not, the process proceeds to s5. .

(S5) The CPU 70 compares the standard moving speed v (t) / 2 and the actual moving speed v ′ (t) / 2. If the actual moving speed is larger than the standard moving speed, the actual moving speed is standard at s6. If it is smaller than the moving speed, the process proceeds to s7.

(S6) The CPU 70 sends a signal to the moving means 41 to change the speed of the movable stopper 40 to v (t) /
Decelerate to 2.

(S7) The CPU 70 sends a signal to the moving means 41 to change the speed of the movable stopper 40 to v (t) /
Accelerate to 2.

Through the above steps, the automatic centering device 1 of the present embodiment is configured so that the conveyor 5 (the article 30
), The centering can be performed by applying feedback to the speed v ′ (t) of the movable stopper 40. That is, when the article 30 finishes passing through the detection sensor 30, the article 30 can be stopped in a state in which the center line that bisects the front end and the rear end thereof matches the basic position.

In the above step, the standard moving speed v (t) / 2 and the actual moving speed v ′ (t) / 2 are compared, but the second encoder 82 uses the actual moving speed v ′ (t) / 2 of the movable stopper 40. The step of detecting may be omitted. That is, the first encoder 80 moves the speed v (t of the conveyor 5
) Is detected (s1), from which the CPU 70 moves the standard moving speed v (t) /
2 is calculated (s2), and a signal is sent to the moving means 41 to change the speed of the movable stopper 40 to v (t) /
2 may be adjusted (s3 ′).

The automatic centering device 1 according to the present invention has been described above, but the automatic centering device 1 according to the present invention is not limited to the above-described embodiment and examples. In the above embodiment, the basic position is the position d in the transport direction from the start end roller 20 of the conveyor, but any position on the transport device 5 can be selected. Further, the installation position of the detection sensor 50 is the start end roller 20.
It is not limited to this position, and as described above, it may be installed at any position of the transfer device 5 that is 1/2 or more away from the basic position in the direction opposite to the transfer direction.

In addition, the present invention can be carried out in a mode in which various improvements, modifications, and changes are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention.

The technology according to the present invention can be used in an automatic centering system for all conveyors that convey articles.

The schematic cross section of the automatic centering apparatus of this invention. (A) (b) (c) (d) (e) The schematic cross section explaining operation | movement of the automatic centering apparatus of this invention with time. The schematic plan view showing operation | movement of the automatic centering apparatus of this invention. The schematic cross section showing the embodiment of the automatic centering device of the present invention. (A) (b) (c) (d) (e) The schematic cross section explaining operation | movement of the automatic centering apparatus of Example 1 of this invention with time. (A) The top view of the automatic centering apparatus of Example 1 of this invention. (B) Sectional drawing of the automatic centering apparatus of Example 1 of this invention. The schematic plan view of the automatic centering apparatus of Example 2 of this invention. The flowchart showing operation | movement of the automatic centering apparatus of Example 2 of this invention. The schematic cross section of the conventional automatic centering apparatus.

Explanation of symbols

1: Automatic centering device 5: Conveying device (conveyor)
10: belt 20, 21: roller 30: article 40: movable stopper 41: moving means 42: pressure sensor 50: detection sensor 60: roller driving device 70: CPU
80: First speed detection encoder 82: Second speed detection encoder 140: Measurement end 141: Stop end 401: Stop surface 1001: Conveyor

Claims (3)

An article having a front end and a rear end is conveyed at a constant speed with the front end directed in the conveyance direction, and the center line of the front end and the rear end is made to coincide with a basic position set in the middle of the conveyance direction. An automatic centering device for positioning the article,
A transport device for transporting the article in the transport direction;
A detection sensor that detects a front end or a rear end of the article and sends a detection signal in a step in which the article is conveyed by the conveyance device;
A movable stopper disposed at the basic position and capable of positioning the front end of the article;
A moving means for moving the movable stopper based on the detection signal in the transport direction at a half speed of the speed at which the article is transported;
With
The moving means starts the movement of the movable stopper in the transport direction simultaneously with the detection sensor detecting the front end of the article,
An automatic centering device that stops the movement of the movable stopper in the transport direction at the same time as the detection sensor detects the rear end of the article. The automatic centering device according to claim 1, wherein the transport device stops transport simultaneously with the movable stopper contacting the front end of the article. The automatic centering device according to claim 1 or 2, further comprising a first encoder that detects a transport speed of the transport device.
The moving means is an automatic centering device that moves the movable stopper in the transport direction at a half speed of the transport speed detected by the first encoder.

Images