JPS598480B2 - Material pressure device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a material pressurizing device for pressurizing granular or powdery materials that can be pressure molded and other materials that can be transferred by various feed screws. , relates to a material pressurizing device, such as a briquette molding machine, in which material is continuously fed between opposing rolls.

In such a briquette molding machine, these rolls are driven at a predetermined speed so that a continuous length of pressed material emerges from between the rolls.

In briquette molding machines and other material pressing devices, it is desirable to use pressure rolls that can be moved laterally in response to the pressure between the pressure rolls.

For example, U.S. Pat. No. 2,977,631 discloses a first pressure roll rotatably mounted on a fixed shaft, and a first pressure roll mounted on a movable support and facing the first pressure roll. A material pressing device is shown, each comprising a second pressure roll.

Said movable bearing is normally tensioned to a predetermined position by a spring t, but when the pressure between the rolls exceeds the pressure of this spring means, said bearing stands against this pressure. Moving.

Preferably, the material pressing device also includes a pressure supply means for supplying the pressurized material to the pressure roll.

Such a screw supply means as a pressure supply means is shown in the aforementioned US patent and US Pat. No. 3,269,611, respectively.

By controlling the rate and pressure of material feeding into the pressure port, the uniformity of the press will be controlled.

The above-mentioned U.S. Pat. No. 2,977,631 discloses a feed screw having control means for controlling the rate at which material is fed to the contact between pressure rolls in order to vary the feed pressure depending on the type of material being handled. control systems are discussed.

Japanese Patent Publication No. 50138230, filed by the applicant of the present application, discloses that a detection means for detecting a change in roll pressure and a control means for controlling a hydraulic feed screw drive means are used to move the pressure rolls between the pressure rolls. An apparatus is described in which the distance between the rollers and the rollers is maintained at a constant distance, thereby driving the feed screw in response to changes in the pressure exerted by the rolls on the material to be pressurized.

The present invention relates to this same technical idea and also relates to control means for operating the electrical drive, which allows for the response to be achieved with a relatively simple construction as well as the effects achieved in the previously mentioned earlier applications. This also has the effect of allowing quick and accurate control.

It is a general object of the present invention to provide an improved operating mechanism for a material pressing device which enables the production of compacts in a highly uniform and efficient yet controllable manner. I have to.

Another object of the present invention is to provide an improved lead screw drive and control system in a briquette molding machine or similar machine, which improves the ability to produce uniform compacts.

These and other objects of the invention will become apparent from the following description.

Although embodiments are shown in the drawings, these embodiments are for illustrative purposes only, and the present invention is not limited to these embodiments.

Next, embodiments of the present invention will be described with reference to the drawings.

The present invention generally comprises opposing pressure rolls disposed so as to be laterally movable relative to each other, and the distance between these rolls changes in response to changes in the pressure between the rolls during material pressure. The present invention relates to a material pressurizing device that is capable of pressurizing materials.

A hopper is provided to receive the pressurized material, and a feed screw is provided within the hopper for feeding the material between the rolls.

The improvements of the present invention primarily relate to the holding mechanism that maintains the distance between the rolls constant so that the pressed product can have a uniform thickness.

For example, in the case of a briquette molding machine, the size of the briquette and the thickness of the connected laminations are controlled, and in the case of sheets, the thickness is controlled.

The rolls are maintained at a constant distance by a system that determines pressure fluctuations during pressurization and adjusts them to compensate, and this adjustment almost immediately cancels out the fluctuations. Ru.

According to the invention disclosed in Japanese Patent Publication No. 50-38230, the desired control is ideally achieved in a system equipped with a hydraulic drive means, for example a hydraulic drive means, for the feed screw for material supply. It turned out that.

Variable displacement pumps or constant displacement pumps are used to supply fluid to a hydraulically driven prime mover, such as a hydraulically driven prime mover.

Detection means are separately provided to detect changes in the pressure applied to the material being pressed by the pressure roll.

When some change is detected, the detection means is arranged to generate a signal proportional to the amount of change.

This signal is then applied sequentially so that the input from the pump to the hydraulic prime mover can be varied accordingly.

The pressure exerted by the lead screw, which introduces a compensating element into this system, therefore varies sequentially.

In reality, the system described here is highly sensitive, so
A pressed product of almost constant thickness is obtained.

This is because changes in the detected pressure are immediately compensated for, so there is no large change in the distance between the rolls.

It has also been found that the motor drive and control system according to the invention can be used effectively in connection with a material feed screw in a pressure forming machine.

In this case, the influence of the pressure exerted by the pressure orifice is preferably detected and transmitted to a process control mechanism which applies its output to the prime mover controller, thereby causing the electric motor for driving the lead screw to become part of the press. controlled to achieve the desired characteristics.

FIG. 1 shows a material pressure forming system 10 having a material feed hopper 12 and a feed screw 14 located within the hopper.

A feed screw 14 supplies the material to be pressed to the contact area between the pressure forming rolls 16 and 17.

Since pockets 19 are formed in each of these press-forming rolls, the press-formed product is composed of a plurality of briquettes, and these briquettes can be used separately.

The pressure forming roll 16 is rotatably mounted within a movable support 18.

The pressure forming roll 1T may be rotatable about a fixed shaft, or may be rotatably attached to a movable support base 20 as shown.

A spring 22 is used to elastically hold the pressure forming rolls 16,17 in the proper distance relationship when the pressure between the rolls exceeds a certain predetermined level; Can be moved.

As long as this distance relationship is maintained, the pressed product emerging from the rolls will have uniform dimensions.

If there are pressure fluctuations between the rolls and the material being pressurized by these rolls, the movable rolls will move against the force of the spring 22 by an amount that depends on the magnitude of the fluctuating pressure.

Since the material being pressurized is usually not homogeneous to some extent, there are often phases of operation in which relatively stiff material is pressurized and the distance between the rolls tends to increase. exist.

Therefore, roll movement as described above generally occurs during pressure molding operations.

First, an embodiment of the invention disclosed in Japanese Patent Publication No. 50-38230 will be described for reference with reference to FIGS. 2 to 5.

FIG. 2 illustrates one system suitable for controlling the movement of a lead screw in a material pressing system.

This makes it possible to obtain a uniform press-molded product.

In this system, rolls 16 and 17 may be of different types, and furthermore, different means may be used to install the rolls.

For example, hydraulic means, such as hydraulic means, may be used on the pedestals 18,20 to resist movement of the pedestals 18,20.

This is because such means can perform the above-mentioned movement if the pressure state changes during the pressurizing operation.

In this system, a hydraulic prime mover, such as a hydraulic prime mover 26, is used to drive the lead screw 14.

A fluid supply pipe 28 and a fluid return pipe 30 extend between the hydraulic motor 26 and a variable displacement hydraulic pump, such as a hydraulic pump 32.

Pump 32 includes a rotating shaft 34 coupled to a first electric motor 36 .

A second electric motor 38 , also coupled to pump 32 , controls the stroke of pump 32 to drive hydraulic motor 26 .
The force applied to the feed screw 14 is controlled by.

The motor 38 is connected by a line 40 to an electrical or pneumatic (eg pneumatic) controller 42 .

The controller is also connected via line 44 to a hole position signal converter 46.

This signal converter 46 may be of any conventional type that electrically detects changes in distance between rolls.

If any variation is detected, a signal is communicated to controller 42, which provides a proportional signal to motor 38.

Depending on the magnitude of this signal, electric motor 38 changes the stroke of pump 32 to cause electric motor 26 to rotate feed screw 14.
change the driving force applied to the

In another embodiment shown in FIG. 3, differential pressure or constant flow signal transducers 50 are connected to tubes 28 and 30 extending between hydraulic prime mover 26 and pump 32, respectively.

Therefore, this signal converter measures the amount of pressure change in this fluid supply pipe 28 and fluid return pipe 30, respectively.

This pressure change creates a signal that is applied to controller 42.

The controller controls the operation of the electric motor 38 so that the pump 32
stroke can be changed.

In the system shown in FIG. 3, the fluid pressure in the fluid supply pipe 28 and the fluid return pipe 30 is changed as the feed screw 14, driven by the hydraulic prime mover 26, changes state.
It is clear that things will change.

For example, if the material fed between pressure rolls increases its density, the pressure exerted on the material by the rolls increases.

The system then automatically attempts to reduce this increase by moving one or both pressure rolls.

However, in this system, large movements are avoided by utilizing the signal emitted by the transducer 50.

In this embodiment, this signal causes the drive pressure applied to the lead screw 14 by the hydraulic prime mover 26 to decrease.

This reduction in drive pressure compensates for the tendency of pressure increase between the pressure rolls, so that the distance between the rolls remains constant.

In yet another embodiment shown in FIG. 4, a current signal converter 52 is associated with a power supply line 54.

This line is connected to an electric motor 56 which serves to drive the pressure roll.

Transducer 52 generates a signal that is transmitted to hydraulic pump 32.
to operate the prime mover 38 associated with the
It is added to the container 42.

The signal generated by converter 52 varies depending on the power required at motor 56.

When the pressure between the roll and the material changes due to variations in the material being pressure-formed, the amount of change causes the electric motor 56 to
The power required changes.

Such changes change the power supply conditions on line 54 and cause a proportional signal to be generated from converter 52.

In this way, the system compensates for the operating conditions of the feed screw 14, so that the conditions between the material to be pressed and the pressure roll can be kept constant.

In yet another embodiment shown in FIG.
is provided for supplying fluid to a hydraulic motor 26 connected to the hydraulic motor 26 .

In this system, the signal is applied by a roll position signal converter 62, such as that used in the system shown in FIG.

This signal converter is connected to an electro-pneumatic signal converter 64 which is provided with a power supply 66 .

A supply pressure regulator 68 is connected to transducer 64 and controller 70, respectively.

This controller performs gas control and is equipped with reset means and the like.

The air signal output of this controller 70 is applied to a flow control valve 72.

This valve 72 is a Taylor Precisor type valve equipped with a compressed air operating body.
type), Foxbomouth/Barbacta type (F
oxboro Valvactor type) may be used.

The flow control valve is connected to pipe 74 between pump 60 and hydraulic motor 26.

This valve therefore controls the operation of the hydraulic prime mover 26 as it determines the flow rate of fluid to the hydraulic prime mover.

In this system, the pump is equipped with a means for dividing the fluid, and the fluid is supplied according to the set amount of the control valve provided in the pipe connected to the outlet of the pump, so it is not a constant discharge pump. This makes it possible to configure this system.

It should be understood that controller 70 and flow control valve 72 may be operated by other signal generating systems, such as those shown in FIGS. 3 and 4.

An adjustable bypass valve can be connected to the controller, thus helping to vary the effectiveness of the pump 60.

It should be understood that in all the systems described above, the hydraulic control of the lead screw 14 is associated with a compensation system.

These systems may also require varying the output of the hydraulic pump to control the force exerted by the feed screw on the material being pressurized.

Figures 6 and 6a illustrate an arrangement embodying features of the invention and using an electrical system.

This mechanism includes a pressure roll 80 and a feed screw 82.

The electric motor 85 may include, for example, (1) a variable speed DC motor operated by a conventionally known SCR and/or thyratron or thyrisk circuit; (2) a variable speed eddy current clutch having a clutch operated by a conventionally known circuit; Motor drive mechanism (variable speed alternating current motor with motor speed controlled by varying the alternating current frequency used in circuits known in the art).

It may be either.

This variable speed controller is designated at 86.

In each of the above, conventionally known motor speed control circuits and
The electrical command signal at \ is applied from the process controller.

This controller may be electrical or pneumatic;
More preferably, it is an electrical controller, as shown at 90 in FIG.

The current applied to the pressurized drive motor 92 is detected by the detection mechanism 881 of the electrical converter 88.

The amount of change in this detected information is measured by the conversion mechanism 882, and the measured amount of change is converted into a signal.

This signal is then provided to process controller 90 via lead 883.

The process controller 90 may be provided with system status sensed from the roll gap position transducer shown in FIG. A sensing method may be used to detect a torque or load applied to the vehicle.

Controller 90 may be any suitable mechanism for operation as described above, whereby signals are communicated to motor controller 86 in response to changes detected in roll drive motor 92.

Therefore, if the operating conditions change such that a greater or lesser demand is made on the motor 92, this is measured by the signal converter with a deviation detected by the process controller 90, and then this process controller The controller provides a correction signal to motor controller 86 to affect the operation of motor 85.

Honeywell Inc.
El Is Inc. A suitable process controller is a Vutronik (TM) deviation display control station of the type manufactured by Vutronik.

A similar controller was developed by Robert Shaw-Fulton.
rtShaw-Fulton), Fischer and Porte
r), General Electric (General
Electric) and others are also manufactured.

Louis Allis and General Electric manufacture motor controllers of the type shown schematically by the numeral 86 in FIG.

Roll gap detectors, electrical position transducers and other means for creating a difference signal may be used, in which case the above description regarding the hydraulic prime mover may be cited as characteristic.

However, the inventive concept is applicable to the above-mentioned measures as well as other measures using electrical drive means for the lead screw.

As mentioned above, various means may be used to determine the signal sent by controller 42, 70, or 90 to volume regulating prime mover 38, flow control valve 72, or prime mover controller 86.

In either case, however, the operation of the controller is determined by its tendency to vary the pressure exerted between the pressing roll and the material being pressed.

It has therefore been recognized that the above-mentioned tendency to change the pressure affects various parts of the system that have measurable elements.

Particularly if the pressure is to increase due to changes in the density of the material, this causes an increase in the distance between the pressure rolls and an increase in the power required for the prime mover to drive the feed screw. That is, it also causes an increase in the power required for the prime mover for driving the shaft.

As mentioned above, signal converters are provided to measure the conditions caused by these trends.

Furthermore, it has been found that the compensation action can be carried out most efficiently by controlling the stroke or displacement of the hydraulic motor used to drive the lead screw.

It should be understood that various variations and modifications may be made in the above-described system incorporating features of the invention without departing from the spirit of the invention.

What is described below belongs to embodiments of the present invention.

(1) The rolls are arranged to be relatively movable and facing each other so that the distance between the rolls changes depending on the pressure generated between the rolls during pressurization of the pressurized material. ,
A material pressurizing device comprising: a feed screw for supplying the pressurized material to the roll; (a) an electric motor for driving the feed screw; and (b)
, a controller for the motor; (c) a process control mechanism for varying the input applied to the motor by the controller; a detection mechanism for detecting a change; (e) a conversion means for measuring the extent of this change and converting the extent of this change into a proportional output; (f) an input of said controller to said electric motor; an application mechanism for applying the proportional output to the process control mechanism to change the spacing between the rolls; A material pressurizing device characterized in that the applied pressure changes directly in accordance with pressure changes between the rolls.

(2) The apparatus described in item 1 above, wherein the pressure exerted by the rolls on the pressurized material is determined by measuring the distance between the rolls.

(3) The apparatus described in item 1 above, wherein the pressure exerted on the pressurized material by the roll is determined by measuring the torque applied to the feed screw.

(4) The roll motor is provided with a roll motor for driving the roll, and the pressure applied to the pressurized material by the roll is determined by measuring the load on the roll motor. The device mentioned in paragraph 1.

(5) The load of the roll prime mover is measured by providing a current signal converter in the power source of the roll prime mover, and the output of the current signal converter is applied to apply a signal to the controller. The fourth part added to the mechanism
The equipment mentioned in section.

As described above, in the material pressurizing device according to the present invention, both the screw drive mechanism and the mechanism for controlling the screw drive mechanism are constituted by electric mechanisms.

Therefore, pressure fluctuations between the rolls are almost immediately canceled out and the distance between the rolls is kept constant, resulting in a press-molded product having a uniform thickness.

Further, the material pressurizing device can also have a relatively simple configuration.

[Brief explanation of drawings]

FIG. 1 is a partially vertical front view of a briquette molding machine to which the present invention can be applied. 2 to 5 are schematic pipe system diagrams of various control systems of the briquette molding machine shown in FIG. 1 disclosed in Japanese Patent Publication No. 50-38230, and FIG. Figure 3 is a schematic pipe system diagram of a control system using a detection means for detecting the distance between ? Fig. 4 is a schematic pipe system diagram of yet another control system using load measuring means, and Fig. 5 is a schematic pipe system diagram of another control system using a detection means for detecting the distance between pressure rolls. It is a schematic pipe system diagram of a control system. FIG. 6 is a schematic wiring diagram of the drive and control mechanism of the electric motor according to the present invention applied to the briquette molding machine shown in FIG.
The figure is a schematic wiring diagram that is an enlarged part of FIG. 6. In the symbols used in the drawings, 10 is a pressure forming system, 12 is a material supply hopper, 14 is a feed screw, 16 and 17 are pressure forming rolls, 26 is a hydraulic motor, and 3
2 is a water pressure pump, 36 and 38 are electric motors, 40 is a line, 46 is a roll position signal converter, 56 is an electric motor, 80 is a pressure roll, 82 is a feed screw, 85 is an electric motor, 86 is a motor controller, 88 is a an electrical converter; 881 is a detection mechanism;
88 is a conversion mechanism, 883 is a conductor, and 90 is a process control mechanism.

Claims (1)

[Claims] 1. The rolls are relatively movable and facing each other so that the distance between the rolls changes in accordance with the pressure generated between the rolls during pressurization of a pressurized material that can be transported by a feed screw. In the material pressurizing device, the material pressurizing device is provided with the rolls disposed in the same manner and a feed screw for supplying the pressurized material to the rolls, (a) an electric motor for driving the feed screw 82; 85
(b) a controller 86 of the electric motor 85; (C) a process control mechanism 90 that changes the input applied to the electric motor 85 by the controller 86; (d) a pressurized object between the rolls 80; a detection mechanism 881 for detecting changes in the pressure exerted by these rolls 80 on the material, (e) a conversion mechanism 882 for measuring the extent of this change and converting this extent into a proportional output; f) an application mechanism 883 for applying the proportional output to the process control mechanism 90 to change the input of the controller 86 to the electric motor 85; The material is characterized in that it is equipped with a mechanism that changes the operating state of the electric motor 85 so that the pressure applied to the material by the feed screw 82 changes directly in accordance with the change in pressure between the rolls 80. Pressure device.