JPH0235688Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a stop control device for a conveyor line.

Recent raw material transportation equipment using belt conveyors is
In order to reduce transportation costs, transportation is becoming increasingly long-distance and large-capacity. In such conveyor equipment, new problems arise in stop control. That is, as shown in FIG.
In configuring a conveyor line by connecting BC1, BC2, and BC3 through chute sections (including small capacity hoppers) SH1 and SH2, conveyors BC1,
When BC2 and BC3 stop, BC2 on the downstream side is stopped earlier than BC1 on the upstream side, and BC on the downstream side than BC2 is stopped.
If 3 is stopped early, the transported items will accumulate or pile up in the chute sections SH1 and SH2, resulting in clogging of the chute section and time-consuming recovery.

Conventionally, belt conveyors BC1 to BC3 have been provided with a brake device, but this brake device is operated by an energy storage spring to stop the brake shoe when the drive coil (hydraulic motor in the case of a hydraulic push-up type) is de-energized. was pressed against the brake drum to always generate a constant braking force. For this reason, depending on conditions such as the amount of objects to be transported and the transport speed, the downstream conveyor may come to a premature stop, resulting in the problem of cargo clogging in the chute section. This will be explained in detail below.

Generally, the stop time of a belt conveyor is expressed by the following equation.

t = GD ² × (N ₀ - N) / 375 × (T _B ±T _L ) ... (1) Here, t is the stopping time (Sec), N ₀ is the rotation speed at the start of braking (rpm), N is the rotational speed at the end of braking (rpm), T _B is the brake torque (Kg・m), T _L is the load torque (Kg・m), and GD ² is the flywheel effect of the conveyor and its transported objects (Kg・m). ² ). this
In equation (1), (T _B + T _L ) corresponds to the upward movement where the conveyor lifts the transported goods to a high position, and conversely (T _B - T _L ) corresponds to the downward movement.

As is clear from equation (1) above, in the case of the conventional constant braking force (constant brake torque T _B ), the stopping time t varies depending on the flywheel effect GD ² and various operating conditions of the load torque T _L. However, the chute may become clogged.

In order to solve this problem, the upstream conveyor is always set based on the equation (1) more than the downstream conveyor even when the operating conditions change, that is, the GD ² and T _L shown in the above equation (1) change. It is conceivable to control the brake torque T _B so that the stopping time is shortened.

However, in conventional electromagnetic brakes, hydraulic push-up brakes, etc., the braking torque is constant, and it is mechanically impossible to automatically control the braking force depending on driving conditions.

In addition, simply stopping the upstream conveyor prematurely will result in an inappropriate stop such as the accumulation of chute being interrupted, and will also result in wasteful operation of the downstream conveyor.

The present invention was developed in view of the above-mentioned circumstances, and aims to provide a stop control device that can appropriately and easily stop an upstream conveyor relative to a downstream conveyor regardless of changes in operating conditions. shall be.

The present invention is characterized by a configuration in which a disc brake with a large braking capacity and easy control of braking force is used as a braking means, and the braking force of the upstream conveyor is controlled by the speed difference between the upstream and downstream conveyors.

FIG. 2 is an apparatus configuration diagram showing an embodiment of the present invention. The objects transported by the upstream belt conveyor BC1 are dropped onto the chute section SH1, and the downstream belt conveyor BC2 has an entrance at the bottom of the chute section SH1.
In conveyor equipment that sequentially transports conveyor BC1 to the most downstream position, a disc brake 1 is provided as a braking means directly connected to each pulley of the conveyor BC1 or its drive unit (electric motor or reduction gear shaft). Both conveyors BC1 and BC2 are provided with tachogenerators 2 and 3 that engage with the belt or are directly connected to the carrier roller or return roller as transportation speed detection means. The respective outputs of the tachogenerators 2 and 3 are suitably amplified (signals Y and X) by amplifiers 4 and 5, and a comparator 6 extracts the deviation. The output of the comparator 6 is input to a stop control amplifier 8 with a limiter through a switch 7 which is turned on when the stop control is started. The output P of the amplifier 8 is converted into a corresponding pressure signal in an electro-pressure converter 9. The electric pressure regulating valve 10 regulates the hydraulic pressure from the pressure generator 11 in accordance with the pressure signal from the converter 9, and applies it as the driving pressure to the pressure pad of the disc brake 1.

In such a configuration, the tachogenerator 2,
3 and amplifiers 4 and 5 are used as other speed detection means such as a pulse pickup and a frequency-voltage converter, but the transport speeds Y and X of conveyors BC1 and BC2 are
are detected respectively. The detection signals Y and X are detected by the comparator 6 as a deviation (speed difference) Z=X-Y. In this state, the switch 7 is turned on to start the stop control, and the input of the stop control amplifier 8 is changed from the zero state to the comparator output Z, and the positive and negative polarity output P corresponding to the input Z is changed to the limiter characteristic. Output with . This output P is converted into a pressure signal by the converter 9 based on the relationship between the braking force of the brake 1 and the hydraulic input, and the hydraulic pressure is controlled by the control valve 10.

Here, if Z (=X-Y) is positive, that is, the speed of conveyor BC1 is slower than that of conveyor BC2, the pressure regulation through the electric-pressure converter 9 is weak, and a small braking force is applied to belt conveyor BC1. ,
When Z is negative, a large braking force is applied to the conveyor BC1. The stopping time due to this braking force is
The braking performance (torque) of BC1 and BC2 and the respective flywheel effects GD ² differ depending on the amount of transport, but
During the stop control, the deviation Z is constantly detected and the braking force is adjusted by changing the speed of each conveyor from the start of the stop control to the end of the stop control, so that the conveyors BC1 and BC2 can be stopped at an appropriate deceleration. In this case, the input/output characteristics of the amplifier 8 or the conversion characteristics of the electric-pressure converter 9 can be appropriately adjusted so that the conveyor
It is also possible to make the stop time difference between BC1 and BC2 more accurate and optimal.

Furthermore, when the downstream conveyor BC2 always has a constant deceleration, a function generator that generates a predetermined deceleration simulant signal can be used instead of the signal from the tachogenerator 3. Furthermore, in equipment with three or more stages in which the next conveyor is connected downstream of the conveyor BC2, the speed detector of the conveyor BC2 is commonly used to compare the speed signal of the next stage.

Further, in the embodiment, a hydraulic type is shown for generating the braking force of the brake 1, but this can of course be replaced by a pneumatic type or an electric type.

As described above, the present invention has a control system that monitors the respective speeds of the upstream conveyor and the downstream conveyor and adjusts the braking force of the disc brake of the upstream conveyor according to the speed difference. This has the effect of eliminating an excess of transported materials at the transit chute between the two, and further controlling the amount of material deposited to an appropriate amount. In addition, since a disc brake is used as a braking means for the conveyor, it is compact, easy to adjust the braking force, and is reliable, and has a high braking reserve, which can cope with an increase in transportation load.

[Brief explanation of the drawing]

FIG. 1 is a conveyor configuration diagram of belt conveyor equipment, and FIG. 2 is a device configuration diagram showing an embodiment of the present invention. BC1, BC2, BC3...Belt conveyor, SH
1, SH2...Chute part, 1...Brake, 2,
3...Tachometer generator, 4, 5...Amplifier, 6
... Comparator, 7 ... Switch, 8 ... Stop control amplifier, 9 ... Electric pressure transducer, 10 ... Pressure control valve, 11 ... Pressure generator.

Claims (1)

[Scope of utility model registration request] In a conveyor line in which items transported by an upstream conveyor are carried into an inlet chute section of a downstream conveyor, and the transport speed changes depending on operating conditions, a disc brake that stops the upstream conveyor with an adjusted braking force, and a stop control. A speed difference detection means detects the speed difference between the speed of the upstream conveyor and the speed of the downstream conveyor at the start, and the disc brake is controlled by using the speed difference as an input and the faster the upstream conveyor is than the downstream conveyor. A stop control device for a conveyor line, comprising: deceleration control means for increasing power.