JPS61192646A - Jamming detection device - Google Patents

Abstract

PURPOSE:To enable jamming to be detected without complex control by judging the condition that no object is detected on the downstream for the period of more than the stated time after it has been detected by an upstream detector permitting the downstream detector to continue detecting for more than the stated time. CONSTITUTION:There are two cases available as for the occurance of jamming. One is the case when a carried object detecting device 11 detects an object 3, but a detecting device 12 does not detect it, and another is the case when the device 11 does not detect the object 3, but the device 12 detects it. When either of the above said cases is satisfied, a jamming condition judgment verification section 8 transmits a signal Sig C to a counter 6 to start counting time. The counter 6 which has received the signal Sig C, continues counting the time while the signal is ON. After the above mentioned condition is found not to be satisfied, the signal Sig C is reset, then a clear signal Sig E is outputted allowing the counter 6 to be set to the initial position. In addition, when the counter has counted up the time which is set in advance, a signal D is outputted. This indicates that jamming will possibly take place firstly between devices 11 and 12 by the above mentioned first condition, and secondly in the downstream beyond the device 12 by the second condition.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a jam detection device for detecting the occurrence of a jam on a conveyance route where objects are intermittently or continuously fed.

(Prior Art) FIG. 5 is a side view of a conventional jam detection device, which detects a jam of an object 3 that is intermittently supplied to a conveyance path 2. This is a condition that the object 3 continues to be detected for a certain period of time (the time required for the transported object to pass a certain point) even though the transported object detection device 1 is used and the transport path 2 is in operation. This is to detect a jam under the conditions.

Here, the fixed time is expressed as Δt' = l' / V (sec), where fi'tQl is the length of the object 3 and V (m/sec) is the transport speed.

(Problem that the invention attempts to solve) The above-mentioned conventional jam detection device is as follows.

(2) In order to set Δt', the length ρ' of the transported object 3 must be limited (standardization of the transported object 3).

■ When the object 3 is conveyed continuously, it is impossible to determine whether a jam has occurred or the object 3 is flowing.

Due to these problems, there is a drawback that the supply of the conveyed object 3 must be controlled using a complicated system in order to detect a jam.

SUMMARY OF THE INVENTION An object of the present invention is to provide a jam detection device that eliminates the above drawbacks and does not require complicated control of a conveyance system.

(Means for Solving the Problems) The jam detection device of the present invention is provided upstream and downstream of a conveyance path at a predetermined distance, and detects objects conveyed on this conveyance path. a state in which the downstream detection device does not detect the object for a certain period of time after the upstream detection device detects the object; and a state in which the upstream detection device does not detect the object and the downstream detection device detects the object. and determining means for determining a state in which the detection is continued for a certain period of time or more.

(Example) Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the jam detection device of the present invention.

This jam detection device is arranged so as to sandwich the transport path 2.
Two conveyed object detection devices fil1 installed upstream and downstream of
1.12, the jam condition determination collation unit 5, the counter unit 6,
It is composed of a count time setting section 7 and a clock generation section 8.

The jam condition judgment/verification unit 5 receives the conveyed object detection signals 8igA output from the conveyed object detection devices 11 and 12, respectively.

The flow of the object 3 on the conveyance path 2 is determined by SigB and compared with the jam occurrence conditions. Here, the jam occurrence conditions are:
The following conditions (a) and (b) are met.

(a) Conveyed object detection device [11 detects object 3, and conveyed object detection device! 112 has not detected object 3. (W
, the relationship between times 'L1 and 12 shown in FIG. (between time T$ and '1'4) When either of the above occurrence conditions (a) or (b) is satisfied, the jam condition determination and collation unit 5 sends a time count start signal Sigh: to the counter 6.

The counter 6 that receives the time count start signal SigC continues counting time while the time count start signal 81gC is in the ON state.

When the state on the conveyance path 2 determined by the output 8igA and BK of the conveyed object detection device 11.12 and the jam condition determination collation unit 5 no longer satisfies the above-mentioned jam occurrence condition (a) or (b), Time count start signal 81gC is Re5et
At the same time, a counter clear signal SigE is outputted from the jam condition judgment/verification section 5, and the color/reference section 6 is initialized.

The waveform diagrams of the signals of the jam detection device when the above jam occurrence conditions 0) and (2) occur and the counter clear signal E is output thereafter are shown in Figures 2 and 3.
In FIG. 3, 8igD is a signal outputted when the counter 6 finishes counting a preset time, and SigG is a count clock outputted from the clock generator 8 and counted by the counter 6.

The above jam occurrence condition (a) is the conveyed object detection device 11 and 1.
Indicates that a jam may have occurred between 2.
The jam occurrence condition (b) indicates that there is a possibility of a jam on the downstream side of 12. Both of the jam occurrence conditions (a) and (b) are such that if no jam occurred, the conditions would no longer be satisfied within a certain period of time. That is,
If jam occurrence condition 0) or (b) is satisfied for a certain period of time or more, it can be said that a jam has actually occurred. Here, the fixed time is the interval j of the transported object detection device 11, 12,
... and is defined as the following Δt as a function of the transport speed v (m/5ec).

Δt-17v+α(5ee) Here, α is the margin time in consideration of the conveyance path and the width of the object.

In the cases shown in FIGS. 2 and 3, the time between time T+ and T2 and between time T8 and T4 is short, within a certain period of time.

The counter 6 counts the time using the count clock S1gG outputted from the clock generation section 8 while the count start signal SigC outputted from the jam condition determination collation section 5 is in an ON state. The time Δt to be counted is determined by the time setting section 7.
The value is set and a signal is sent to the value counter 6.

Both the count clock SigG and the fixed time Δt can be arbitrarily set depending on the state of the transport path 2 and the state of the transported object 3. D. It was necessary to set the constant time Δt for a long time.
(1/V and α are large), if the conveyed object 3 is large, increase the pulse width of the count clock 8igG or increase the count number of the counter 6.
This can be dealt with by increasing t, etc.

When jam occurrence condition 0) or (b) continues for a certain period of time Δ or more, when the counter 6 counts for a certain period of time Δt (time Ts shown in FIG. 5), a count end signal 8 is generated.
The igD is output to the jam condition determination collation unit 5. When the jam condition determination and collation unit 5 receives SigD, it determines that a jam has occurred on the conveyance path 2, and outputs a jam signal SigH.

(Effects of the Invention) As explained above, the jam detection device of the present invention is a system that can detect jams during continuous conveyance of objects by providing two conveyance object detection devices on the upstream and downstream sides of the conveyance path. This has the effect of eliminating the need for complex control for intermittently supplying conveyed objects.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG.
FIG. 4 shows the signal waveform 1 of the embodiment shown in FIG. 1 when the jam occurrence condition (a) occurs within a certain time, when the jam occurrence condition (b) occurs within a certain time, and when the jam occurrence condition If this occurs for a certain period of time or more, FIG. 5 is a side view of a conventional jam detection device. 1, 11.12...Conveyed object detection device, 2...Curved conveyance path, 3...Object, 5...Jam condition determination collation unit, 6... ...Counter, 7...
・Count time setting unit, 8...Clock generation unit, 8igA, 8igB...Conveyed object detection device 1
1.12 signals, 8igC... Time count start signal, SigD... Count end signal, S
igE... Counter clear signal, SigF...
・・・・Set signal Δ, fast mouth S'121

Claims (1)

[Claims] Upstream and downstream detection devices are provided upstream and downstream of a conveyance path at a predetermined distance to detect an object conveyed on the conveyance path, and after the upstream detection device detects the object, the determination means for determining a state in which the downstream detection device does not detect the object and a state in which the upstream detection device does not detect the object and the downstream detection device continuously detects the object for a certain period of time or more. A jam detection device characterized by: