JP2000136021A - Induction conveyor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an induction conveyor capable of automatically adjusting carrier space of articles to be fed into a sorting conveyor and displaying sorting capability of the sorting conveyor to the utmost. SOLUTION: When space before and after articles W1 and W2 is narrower than designated carrier space A, a carrier belt 1A is decelerated from carrier speed V by acceleration-α for prescribed time Δt/2 after the preceding article W1 is transferred to the side of a sorting conveyor of carrier speed V, continuously, the carrier belt 1A is accelerated by acceleration α for prescribed time Δt/2 and space before and after articles on the sorting conveyor is adjusted to the designated space A. When space before and after articles is wider than the carrier space A, the carrier belt 1A is accelerated from carrier speed V by acceleration α(α>0) for prescribed time Δt'/2. continuously the carrier belt 1A is decelerated by acceleration-α for prescribed time Δt'/2 and space before and after articles on the sorting conveyor is adjusted to the designated carrier space A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction conveyor capable of transferring a conveyed article to a sorting conveyor with a constant front-rear interval.

[0002]

2. Description of the Related Art In a conventional sorting conveyor as disclosed in Japanese Patent Publication No. 8-615, a large number of slide shoes are provided for pushing articles from a conveying surface to a side sorting position. .

When the articles are conveyed to the vicinity of the sorting position, these slide shoes are guided by a switch unit provided below the conveying surface, slide laterally with the movement of the conveying surface, and move the articles to the sorting position. To a chute or the like arranged in

[0004]

In order to sort articles by the above-described sorting conveyor, it is necessary to secure a certain interval between articles before and after being placed on a conveying surface. In order to prevent the sorting operation from being hindered when the articles are loaded into the hopper, the articles are loaded at an unnecessarily long transport interval.

[0005] Therefore, there is a problem that the efficiency of the sorting operation is low and the sorting ability of the sorting conveyor cannot be sufficiently exhibited.

Accordingly, the present invention solves the above-mentioned problems of the prior art, and automatically adjusts the conveying interval of articles to be put into a sorting conveyor to maximize the sorting ability of the sorting conveyor. It is an object of the present invention to provide an induction conveyor capable of performing the above-described operations.

[0007]

To achieve the above object, an induction conveyor according to the present invention comprises a conveyor belt in which a downstream end of a conveying surface is arranged substantially horizontally in a continuous manner at an upstream end of a conveying surface of a sorting conveyor. A drive source capable of accelerating and decelerating the transport belt based on a transport speed V equal to the transport speed of the sorting conveyor, and the transport direction length of the articles transported to the sorting conveyor near the downstream end of the transport surface of the transport belt is the shortest. A first article detection sensor arranged corresponding to a position at which the rear end of the article passes when the center of gravity of the article moves;
A second article detection sensor arranged at a predetermined interval a upstream of the first article detection sensor on the conveyance surface of the conveyance belt, and a conveyor for sorting the first article detection sensor upstream of the conveyance surface of the conveyance belt; A third article detection sensor arranged at a distance equal to the conveyance interval A between the articles specified above, and a predetermined distance b from the third article detection sensor to the upstream side of the conveyance surface of the conveyance belt. And a drive control means for controlling the drive source based on the output signals of the first to fourth article detection sensors to change the transport speed of the transport belt. I have.

The drive control means includes a time t from when the first article detection sensor detects the trailing end of the preceding article conveyed on the conveyor belt to when the second article detection sensor detects the front end of the succeeding article. , A time t ′ from when the fourth article detection sensor detects the front end of the succeeding article to when the first article detection sensor detects the rear end of the preceding article.

When the third article detection sensor detects the succeeding article at the time when the first article detection sensor detects the trailing end of the preceding article, the drive control means includes a second article detection sensor. Decelerates the transport belt from the transport speed V at the acceleration -α by the time Δt / 2 from the time when the front end of the subsequent article is detected, and then accelerates the acceleration belt by the time Δt / 2 at the acceleration α to set the transport interval A between the preceding and following articles. adjust.

If the third article detection sensor has not detected the succeeding article at the time when the first article detection sensor has detected the trailing end of the preceding article, the first article detection sensor will not detect the trailing end of the preceding article. From the time when the end is detected, the transport belt is accelerated from the transport speed V by the acceleration α by the time Δt ′ / 2, and then decelerated by the acceleration −α by the time Δt ′ / 2 to specify the transport interval A between the preceding and following articles. Adjust to

Here, α> 0 Δt = 2√ ((A−a−Vt) / α) Δt ′ = 2√ ((b−Vt ′) / α) a = A−α ((A + y ) / 2V) ² b = A + α ((A + y) / 2V) ² y: Minimum length of the article in the transport direction

[0012]

When the transport interval before and after articles sequentially fed to the upstream end of the transport surface of the transport belt of the induction conveyor is narrower than the specified transport interval, the rear end of the preceding article has passed the first article detection sensor. Then, from the point in time when the second article detection sensor detects the front end of the succeeding article, the drive control means causes the transport speed of the transport belt to increase in the direction opposite to the transport direction.
is decelerated by α at time Δt / 2.

On the other hand, after the leading end of the preceding article has passed the position of the first article detection sensor, the center of gravity of the article moves to the sorting conveyor side, and thereafter, is conveyed at a speed V on the conveying surface of the sorting conveyor. Is done.

As a result, the transport interval between the preceding and following articles starts to increase. After the elapse of the time Δt / 2, the conveyance speed of the conveyor belt is accelerated by the acceleration α in the conveyance direction by the time Δt / 2, and is returned again to the conveyance speed V equal to the sorting conveyor. Thereafter, when the succeeding article is transferred to the sorting conveyor, the preceding and following articles on the sorting conveyor have the specified transport interval A.

If the transport interval of the articles before and after being sequentially fed into the transport belt upstream end of the transport belt of the induction conveyor is wider than the specified transport interval A, the front end of the succeeding article is detected by the fourth article detection. After passing through the sensor, the drive control means accelerates the transport speed of the transport belt by a time Δt ′ / 2 at a constant acceleration α from the time when the first article detection sensor detects the front end of the preceding article.

After the leading end of the preceding article has passed the position of the first article detecting sensor, the preceding article is conveyed on the conveying surface of the sorting conveyor at the speed V, so that the conveying interval between the preceding and following articles starts to narrow.

After a lapse of time Δt ′ / 2, the conveying speed of the conveyor belt is reduced by a time Δt ′ / 2 at a constant acceleration −α, and the conveying speed V equal to the sorting conveyor is again obtained.
Returned to Thereafter, when the succeeding article is transferred to the sorting conveyor, the preceding and following articles on the sorting conveyor have the specified transport interval A.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the induction conveyor 1 of the present invention is disposed between a sorting conveyor 2 and a carry-in conveyor 3.

These conveyors 1, 2 and 3 are provided with conveyor belts 1A, 2A,
3A, the sorting conveyor 2 and the carry-in conveyor 3 are driven at a constant conveyance speed.

The conveying speed of the carry-in conveyor 3 is set lower than the conveying speed of the sorting conveyor 2, and the induction conveyor 1 controls the conveying speed of the sorting conveyor 2 by a variable-speed drive source (not shown). It is configured such that acceleration and deceleration can be performed at a constant acceleration based on a speed equal to the transport speed.

Accordingly, the induction conveyor 1 accelerates or decelerates the article W on the conveyor belt 1A on the way, thereby causing the induction conveyor 1 to decelerate.
For the preceding article that has moved to the sorting conveyor 2 from
It is possible to increase or decrease the conveyance interval of the subsequent article.

In order to control the timing of acceleration / deceleration of the conveying speed of the induction conveyor 1, the induction conveyor 1 includes a first object for detecting an article W conveyed on the conveying surface of the conveying belt 1A. A detection sensor PT1, a second object detection sensor PT2, a third object detection sensor PT3, and a fourth object detection sensor PT4 are provided.

These article detection sensors PT1, PT2,
For PT3 and PT4, a photosensor composed of a light-emitting unit and a light-receiving unit disposed opposite to a fixed position on both sides in the width direction of the conveyor belt 1A is used. The signal output is OFF when the light is received, and when the article W passes between the light emitting section and the light receiving section, the ON signal is turned off when the light incident on the light receiving section is blocked by the article W. Output.

Further, these article detection sensors PT1, P
The output signals of T2, PT3 and PT4 are sent to drive control means constituted by a microcomputer or the like (not shown) for arithmetic processing, whereby the drive source of the induction conveyor 1 is controlled by the drive control means. I have.

The article detection sensor PT1 disposed on the most downstream side of the induction conveyor 1 is located slightly before the downstream end of the induction conveyor 1 from a position O where the conveyor belt 2A at the upstream end of the sorting conveyor 2 becomes horizontal. They are spaced apart by an interval L on the upstream side in the transport direction.

The interval L is set such that when the rear end of the article W has passed the article detection sensor PT1, the center of gravity of the article W is placed on the conveyor belt 2A side of the sorting conveyor 2 and the articles to be loaded into the carry-in conveyor 3 are separated. It is set to approximately half of the minimum length of W in the transport direction.

Therefore, if the article W is the article detection sensor PT
1, the conveyor belt 2A of the sorting conveyor 2
Most of the weight moves to the side, and is conveyed downstream at the conveying speed of the sorting conveyor.

The article detection sensor PT2 is arranged at a position upstream of the article detection sensor PT1 and separated by a predetermined distance a. Further, the article detection sensor PT3
It is arranged at an interval A on the upstream side in the transport direction from the article detection sensor PT1.

The interval A is set to an appropriate transport interval between articles W to be taken on the sorting conveyor 2.

Further, the article detection sensor PT4 is arranged at a position upstream of the article detection sensor PT3 at a predetermined interval b.

Next, the operation of the induction conveyor 1 of the present invention configured as described above will be described. FIG. 2 shows an operation in which the articles W1 and W2 before and after being conveyed at a narrow conveyance interval on the carry-in conveyor 3 are adjusted to an appropriate conveyance interval A and delivered to the sorting conveyor 2 side.

In FIG. 2A, the carry-in conveyor 3 is driven at a transfer speed v, and the sorting conveyor 2 is driven at a transfer speed V higher than the transfer speed v.
The induction conveyor 1 is driven at the same transport speed V as the sorting conveyor 2.

Therefore, when the preceding article W1 conveyed on the carry-in conveyor 3 at the carry speed v is transferred to the induction conveyor 1, the preceding article W1 is conveyed at a carry speed V higher than this, and the two articles W1, W2 on the carry-in conveyor 3 are moved. When the preceding article W1 is transferred to the induction conveyor 1, the subsequent article W2
Pulled away from.

When the article detection sensor P1 detects the rear end of the preceding article W1, the article detection sensor P3 detects the succeeding article W2.
Is detected, the drive control means determines that the preceding article W
It is determined that the transport interval between 1 and the succeeding article W2 is narrower than the appropriate transport interval A, and the following control is performed to narrow the transport interval.

The drive control means includes an article detection sensor PT
1 when the rear end of the article W1 passes through the position 1, ie,
From the time when the output signal of the article detection sensor P1 is inverted from ON to OFF, a timer built in the drive control means starts measuring time, and the front end of the article W2 is sent to the article detection sensor PT2 as shown in FIG. Is reached and the elapsed time t until the article detection sensor PT2 is turned ON is measured.

On the other hand, when the article detection sensor PT2 detects the front end of the article W2, the rear end of the preceding article W1 is further advanced by Vt from the position of the article detection sensor PT1. The interval before and after W2 is a
+ Vt.

Here, in order to adjust the interval to an appropriate transport interval A, the drive control means adjusts the transport speed of the induction conveyor 1 from a reference speed V equal to the transport speed of the sorting conveyor 2 to a constant acceleration -α. The speed is reduced by a predetermined time Δt / 2, then accelerated by a constant acceleration α equal in magnitude to the acceleration −α by a time Δt / 2 equal to the deceleration time, and the transport speed of the induction conveyor 1 is again set to the reference speed V. Control to return to. Here, α> 0.

In this manner, when the time Δt further elapses from the state of FIG. 2B, as shown in FIG. 2C, the preceding article W1 is further shifted by VΔt from the position of FIG. 2B. On the other hand, the front end of the following article W2 advances from the position of the article detection sensor PT2 by the interval x, and the transport interval between them is equal to the interval A.

At this time, since the interval between the rear end of the preceding article W1 and the article detection sensor PT2 is a + Vt + VΔt, the proper transport interval A can be expressed by the following equation. A = (a + Vt + VΔt) −x (1) Here, the interval at which the article W2 advances during deceleration at the acceleration −α is:
V (Δt / 2) − (1/2) α (Δt / 2) ² ,
On the other hand, the interval at which the acceleration α advances during acceleration is V ₀ (Δt /
2) + (1/2) α (Δt / 2) ² . Where V
₀ is the conveyance speed at the end of the deceleration of the article W2, and V ₀ =
V−α (Δt / 2).

[0040] Thus, x = VΔt-α (Δt ) 2/4 ··· (2) Therefore, from equation (1) and (2), the seek Δt, Δt = 2√ ((A -a- Vt) / α) (3) That is, the acceleration / deceleration time Δt of the article W2 is calculated from the measured elapsed time t based on the equation (3).

The article W2 has the center of gravity of the sorting conveyor 2.
By the time the vehicle passes the position of the article detection sensor PT1 moving to the side, the induction conveyor 1 needs to return to the transport speed V, and the condition is that a + y ≧ x
(2) from the equation, a + y ≧ VΔt-α (Δt) 2/4 ··· (4) where, a is the acceleration and deceleration of the conveying speed of the induction conveyor 1, the interval between the preceding article W1 and the subsequent article W2 Is the minimum interval that can be corrected to an appropriate transport interval A. If t = 0 in the equation (3), Δt = 2√ ((A
−a) / α), the value of Δt is substituted into equation (4) to obtain a = A−α ((A + y) / 2
V) ² ... (5).

Next, FIG. 3 shows that the articles W1 and W2 before and after being conveyed on the carry-in conveyor 3 at a wider carry interval than the proper carry interval A are adjusted to the proper carry interval A to sort the conveyor 2 side. This is an operation to be transferred to the server.

As in the case described above, the carry-in conveyor 3 is driven at the transfer speed v, and the sorting conveyor 2 is driven at the transfer speed V. The induction conveyor 1 is initially driven at the transfer speed V like the sort conveyor 2. It is driven by.

As shown in FIG. 3A, from the time when the front end of the succeeding article W2 is detected by the article detection sensor PT4, as shown in FIG. 3B, the rear end of the preceding article W1 is moved to the article detection sensor PT1. Is measured by the drive control means.

When the article detection sensor P1 detects the rear end of the preceding article W1, the article detection sensor P3 detects the succeeding article W2.
Is not detected, the drive control means determines that the transport interval between the preceding article W1 and the succeeding article W2 is wider than the appropriate transport interval A, and performs the following control for narrowing the transport interval. I do.

As shown in FIG. 3B, the article detection sensor PT
1 detects the rear end of the article W1, the subsequent article W2
Is advanced by Vt ′ from the position of the article detection sensor PT4, and the front-back distance between the article W1 and the article W2 at this time is A + b−Vt ′.

Here, in order to adjust the interval to an appropriate transport interval A, the drive control means adjusts the transport speed of the induction conveyor 1 from a reference speed V equal to the transport speed of the sorting conveyor 2 at a predetermined acceleration α. The acceleration is accelerated by the time Δt ′ / 2, and then decelerated by the constant acceleration −α equal in magnitude to the acceleration α by the time Δt ′ / 2 equal to the acceleration time, and the transport speed of the induction conveyor 1 is again set to the reference speed. Control to return to V is performed.

In this way, when the time Δt ′ further elapses from the state of FIG. 3B, as shown in FIG. 3C, the preceding article W1 further moves from the position of FIG.
The front end of the following article W2 advances by t ', and the front end of the succeeding article W2 advances by an interval x', and the transport interval between the two becomes equal to the transport interval A.

Referring to FIGS. 3B and 3C, article detection
The interval from the sensor PT3 to the preceding article W1 is: A + VΔt ′ = A + x ′ − (b−Vt ′) (1 ′) Here, the interval at which the article W2 advances during acceleration at the acceleration α is V
(Δt ′ / 2) + (1/2) α (Δt ′ / 2)^TwoIn
On the other hand, the interval at which the vehicle advances during deceleration at the acceleration -α is V₁(Δ
t ′ / 2) − (1/2) α (Δt ′ / 2)^Two It is. Was
But V ₁Is the speed at the end of acceleration of the article W2, and V
₁= V + α (Δt ′ / 2).

[0050] Thus, x '= VΔt' + α (Δt ') from ^2/4 (2') (1 ') and (2') where, Δt '= 2√ ((b -Vt') / Α) (3 ′) That is, based on the measured elapsed time t ′, the article W2
Is calculated based on the equation (3 ′).

The article W2 has the center of gravity of the sorting conveyor 2
By the time the vehicle passes the position of the article detection sensor PT1 moving to the side, the induction conveyor 1 needs to return to the transport speed V. The condition is that the minimum transport direction length of the article to be handled is y, and b + A + y ≧ x 'because it is, (2' from) formula, b + a + y ≧ VΔt '+ α (Δt') 2/4 ··· (4 ') where, b is the acceleration and deceleration of the conveying speed of the induction conveyor 1, the prior article This is the maximum interval at which the interval between W1 and the succeeding article W2 can be corrected to an appropriate transport interval A. If t ′ = 0 in equation (3 ′), Δt ′ = 2√
Since (b / α), by substituting the value of Δt ′ into the equation (4 ′), b = A + α ((A + y) / 2
V) ² ... (5 ′).

In the above-described embodiment, the transmission type photosensor in which the light emitting unit and the light receiving unit are opposed to both sides of the conveying surface is used for the article detection sensors PT1 to PT4, but the present invention is not limited to this. Other types of article detection sensors, such as a reflection type photosensor with an integrated light receiving unit, may be used.

In this embodiment, the articles are loaded into the induction conveyor 1 using the carry-in conveyor 3, but the articles may be directly loaded into the induction conveyor manually without using the carry-in conveyor 3. In this case, even if the feeding interval varies to some extent, it is automatically corrected by the induction conveyor 1, and the articles can be supplied to the sorting conveyor at the optimum transport interval.

[0054]

As described above, according to the induction conveyor of the present invention, the conveyance interval of the articles is automatically adjusted during the conveyance so that the articles are always supplied to the sorting conveyor at the optimum conveyance interval. As a result, the sorting capacity of the sorting conveyor can be maximized.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing one embodiment of an induction conveyor according to the present invention.

FIG. 2 is an explanatory diagram of an operation in a case where a conveyance interval of articles is increased on an induction conveyor according to the present invention.

FIG. 3 is an operation explanatory diagram in a case where the conveyance interval of articles on the induction conveyor of the present invention is narrowed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Induction conveyor 2 Sorting conveyor 3 Loading conveyor 1A, 2A, 3A Conveying belt PT1, PT2, PT3, PT4 Article detection sensor

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3F027 AA02 CA01 DA08 DA12 EA01 FA03 FA04 FA12 3F081 AA01 BD08 BD15 CC08 EA04 EA05 EA10 EA12 FB02

Claims (1)

[Claims] 1. A conveying surface at an upstream end of a conveying surface of a sorting conveyor.
Conveyor belt whose downstream end is continuously arranged in a substantially horizontal direction
Transporting the transport belt at a speed equal to the transport speed of the sorting conveyor.
A drive source capable of accelerating and decelerating based on the feeding speed V; and a sorting conveyor near the downstream end of the conveying surface of the conveying belt.
The center of gravity of the item with the smallest transport direction length
Corresponds to the position where the rear end of the article passes when moving
A first article detection sensor arranged in a position, and an upstream side of the conveyance surface of the conveyance belt from the first article detection sensor.
A second article detection sensor arranged at a predetermined interval a
And from the first article detection sensor to the upstream side of the conveying surface of the conveying belt.
For example, the transport interval A between articles specified on the sorting conveyor
Third article detection sensor spaced apart by a desired distance
And from the third article detection sensor to the upstream side of the conveying surface of the conveying belt.
A fourth article detection sensor spaced at a predetermined interval b
And an output signal of the first to fourth article detection sensors.
Control the drive source to change the transport speed of the transport belt.
Drive control means for causing the first article detection sensor to carry the transport bell.
After detecting the trailing edge of the preceding article conveyed on the
Time t until the article detection sensor detects the front end of the following article
And whether the fourth article detection sensor detects the front end of the subsequent article
Until the first article detection sensor detects the trailing end of the preceding article.
At the time when the first article detection sensor detects the trailing edge of the preceding article.
In the case where the third article detection sensor is detecting a subsequent article,
In this case, the second article detection sensor detects the front end of the succeeding article.
From the time when the conveyor belt is moved from the conveying speed V to the acceleration -α.
After deceleration by Δt / 2 for a time, it is time Δt / 2 with acceleration α
At the time when the first article detection sensor detects the trailing edge of the preceding article.
And the third article detection sensor has not detected the subsequent article
In this case, the first article detection sensor detects the trailing end of the preceding article
From the point at which the conveyor belt is moved at an acceleration α from the conveyor speed V.
After accelerating by the time Δt ′ / 2, the time Δ
Decrease by t '/ 2 to adjust the distance between the preceding and following articles to a predetermined transport interval A.
Induction control characterized by adjustment
Beya. Here, α> 0 Δt = 2√ ((A−a−Vt) / α) Δt ′ = 2√ ((b−Vt ′) / α) a = A−α ((A + y) / 2V)^Two  b = A + α ((A + y) / 2V)^Two y: Minimum length of the article in the transport direction