JPH09131726A - Weight operating apparatus for batch mixer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attempt to improve the kneading effect and productivity by lowering the entire height of an apparatus and height of a building, shortening the weight vertically moving time, regulating applied pressure and preventing the overload and to reduce the cost. SOLUTION: The weight operating apparatus for a batch mixer comprises a floating weight 27 vertically movable in a hopper 24 above the inlet of a kneading chamber, a cylinder 31 vertically moved by elevation means 33 and provided above the weight 27, a piston 29 engaged within the cylinder 31, wherein the piston 29 is coupled to the weight 27 via a piston rod 28. In this case, a free piston 30 externally engaged with the rod 28 and vertically moved in the cylinder 31. An upper chamber 38 and a lower chamber 36 are formed above and below the piston 29 in the cylinder 31, and control air tubes 37, 39 are connected to the chambers 38, 36 via supply and exhaust valves 44, 45.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floating weight operating device in a closed batch type mixer mainly used for kneading plastic materials such as rubber and plastic materials.

[0002]

2. Description of the Related Art Generally, a batch type mixer shown in FIG. 7 is known. This mixer is
Hopper 2 connected to material inlet 1A of mixer body 1
A predetermined amount of material to be kneaded is charged into the kneading chamber 5 through the charging port 3, and the material is pushed into the kneading chamber 5 by the floating weight 4 provided in the hopper 2 so as to be vertically movable. In the closed state, the pair of rotors 6 is rotated in the direction of the arrow to knead, and after the kneading, the lower drop door 7 is opened to discharge the material to the outside of the machine.

In order to satisfactorily knead the material, it is necessary to apply an appropriate pressing force to the material in the kneading chamber 5. Therefore, the floating weight 4 has an appropriate cushioning property in the vertical direction. Elevating means is provided for raising the material to a position near the charging port 3 so as not to hinder the charging operation when charging the material. Conventionally, as a floating weight actuating device, one illustrated in FIG. 6 is known (see Japanese Utility Model Publication No. 61-40336).

This device is equipped with a hopper 2 of a mixer body 1.
The floating weight 4 movably provided in the inside is vertically movably fitted to a cushion cylinder 8 whose lower end is open, and a retaining ring 9 at the lower end of the cylinder 8 is attached.
And a ball screw nut 14 rotatably supported by a support frame 12 erected on the hopper 2 via a bearing 13 and a vertical movement thereof. Ball screw 15 and the nut 1 that are freely screwed together
Elevating means 17 including drive motor 16 for rotating 4
The cylinder 8 is connected to the lower end of the screw 15.

Then, when the cushion cylinder 8 is lowered so that the weight 4 is located at the lower limit, a lower limit stopper 18 which is fitted in the retaining ring 9 and contacts the piston 10 from the lower side is provided. Support plate 19 on top
When the piston 10 comes into contact with the stopper 18, a gap is formed between the retaining ring 9 and the support plate 19.

[0006]

In the above-mentioned prior art, the cushion cylinder 8 can prevent the kneading failure of the material, prevent the overrun at the time of descending, and raise and lower the impact 1 due to the vertical movement of the floating weight 4.
It is possible to improve durability without directly affecting 7.

However, the cushion cylinder 8 requires a considerably long stroke (200 to 300 mm), requires a large building with a large total height of the apparatus, and requires a long stroke movement time to reduce productivity, and the adjustment of the pressing force of the floating weight. However, it is not suitable in terms of preventing overload and improving the kneading effect. The present invention has been made in view of the above situation, and its object is to reduce the height of the building by lowering the overall height of the device, shortening the lifting time of the floating weight, and adjusting the applied pressure. Enable overload prevention, kneading effect and productivity improvement,
Another object of the present invention is to provide a floating weight operating device of a batch type mixer that can reduce the cost.

[0008]

According to the present invention, the following technical measures have been taken in order to achieve the above object. That is, according to the present invention, a floating weight for opening and closing the material inlet is provided in a hopper above the material inlet to the kneading chamber of the mixer so as to be vertically movable, and is vertically moved above and below the weight by an elevating means. A lower open cylinder is provided,
A weight actuating device in which a vertically movable piston is fitted in the cylinder, and the piston and the floating weight are connected to each other via a piston rod. And a lower chamber formed between the piston and the free piston, in which a free piston that moves up and down is fitted and a piston retaining ring is provided at the lower end of the cylinder, and the upper chamber is formed above the piston of the cylinder. Is connected to a control air pipe through which a supply / discharge valve is interposed, respectively (Claim 1).

According to the present invention, since the upper chamber and the lower chamber are formed above and below the piston, control air is supplied to the lower chamber when the floating weight is raised and at the upper limit position so that the piston is positioned at the upper limit and the floating weight is adjusted. At the time of descent and at the lower limit position, the control air can be supplied to the upper chamber to position the piston at or near the lower limit, and the device height is lowered by the stroke of the piston.

In this case, at the lower limit position of the floating weight, since the control air is supplied to the upper chamber, a cushioning function is exerted during kneading, overload can be prevented, and the kneading effect can be enhanced. Also, during kneading, control air having the same pressure is supplied to the upper chamber and the lower chamber,
When the rotor phase is within the specified range, the floating pressure is released and the pressure is adjusted.
It is possible to prevent the occurrence of overload, prevent damage to the device, and enhance the kneading effect.

Further, according to the present invention, by disposing the stopper with which the free piston comes into contact with the upper end portion of the hopper, the floating weight can be accurately positioned and stopped at the lower limit position, and the impact is not directly transmitted to the cylinder, It is possible to prevent overload on the elevating means (claim 2). further,
According to the present invention, a brake mechanism can be provided in the elevating means, so that the cylinder can be reliably stopped and held at the stop position with high accuracy, so that the control air is provided in the upper and lower chambers of the cylinder. It is possible to accurately and surely control the operation of the floating weight by supplying / discharging.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. In FIGS. 1 and 2, reference numeral 20 denotes a floating weight operating device of a batch type mixer adopting the present invention, and a supporting plate 25 is provided on a hopper 24 provided above a material charging port 23 to a kneading chamber 22 of a mixer main body 21.
It is attached to the support frame 26 which is erected via the.

Numeral 27 is a floating weight, which is arranged in the hopper 24 so as to be vertically movable and has a material charging port 2
3 is openable and closable, and a piston 29 is connected to the upper surface of the weight 24 via a piston rod 28. An annular free piston 30 having the same outer diameter as the piston 29 is airtightly and slidably fitted onto the piston rod 28.

Reference numeral 31 denotes a cylinder which is open at the bottom, and which is attached to the support frame 26 and the upper support plate 32 attached to the upper end of
It is vertically movably mounted concentrically with the shaft center of the piston 29 and its rod 28 via an elevating means 33, and both pistons 29, 30 are vertically movably and airtightly fitted in the cylinder 31. A piston retaining ring 34 is fixed to the lower open end of the cylinder 31.

The head cover 31A and the retaining ring 34 of the cylinder 31 are provided with outward flange portions, and a plurality of weight cooling pipes 35 are slidably pierced through them.
The outer periphery of the flange is guided by the support frame 26. Also, a control air pipe 37 communicating with a lower chamber 36 formed between both pistons 29 and 30 in the cylinder 31 is connected to the cylinder 31 at the lower portion, and the cover 31A is formed above the piston 29. A control air pipe 39 communicating with the upper chamber 38 is connected.

The weight cooling pipe 35 is connected to the support plate 2 by the weight cooling pipe 35.
5, the upper support plate 32 is slidably penetrated, and the lower end is connected to the floating weight 27. The support plate 2
5, a piston rod through hole 40 is provided in the center,
A ring-shaped stopper 42 having a piston rod through hole 41 concentric with the hole 40 is fixed to the upper surface of the support plate 25. The stopper 42 has an outer diameter smaller than the inner diameter of the retaining ring 34, so that the retaining ring 34
An elastic material 43 such as rubber is fixed to the upper surface of the free piston 30 so that the lower surface of the free piston 30 contacts the stopper 42 via the elastic material 43.

The control air pipes 37 and 39 are connected to a pressure air source 46 via supply / discharge valves 44 and 45, respectively. The elevating means 33 is a screw shaft support (ball screw nut) arranged on the axis of the piston rod 28.
47, a screw shaft (ball screw) 48 screwed to the screw shaft support body 47 through a ball so as to be vertically movable, a motor 49 for rotating the screw shaft support body 47, and the screw shaft support body 47. It is composed of timing pulleys 50 and 51 and a timing belt 52 that are interlocked with a motor 49.

The screw shaft support 47 is held by the upper support plate 32 and the upper support member 53 provided upright on the screw shaft support 47 via bearings 54 and 55 so that the screw shaft support 47 is rotatable but not vertically movable. Brake 5 mounted on the underside of
6, the brake is applied and stopped, and the position is accurately fixed. The lower end of the screw shaft 48 is non-rotatably connected to the head cover 31A of the cylinder 31 to move the cylinder 31 up and down.

Reference numeral 57 is an upper limit switch of the cylinder 31, 58 is a lower limit switch of the cylinder 31, both switches 57 and 58 are attached to the support frame 26,
The retaining ring 34 is operated to stop the operation of the motor 49 and at the same time, to operate the brake 56 to accurately stop and fix the cylinder 31 at the upper and lower limit positions.

Incidentally, instead of the brake 56, the motor 49 may be provided with an electromagnetic brake. In the above embodiment, when the material to be kneaded is supplied into the kneading chamber 22 of the mixer 20, the floating weight 27 and the cylinder 31 are raised to the upper limit position and the motor 49 is stopped, as shown in FIG. During operation, the brake 56 supplies pressurized air to the lower chamber 36 of the cylinder 31 to bring the piston 29 to the upper limit position and the free piston 30 to the lower limit position to feed material into the hopper 24.

Upon completion of the material charging, the brake 56 is opened to activate the motor 49, rotate the screw shaft support 47 to feed the screw shaft 48 downward, and at the same time, the air in the lower chamber 36 of the cylinder 31 is discharged. Then, pressurized air is supplied to the upper chamber 38 of the cylinder 31 to move the piston 29 to its full stroke SP.
The floating weight 27 is pushed down and lowered as shown in FIG.

When the cylinder 31 reaches the lower limit position, when the lower surface of the free piston 30 abuts on the elastic member 43 of the stopper 42, the lower limit switch 58 is actuated by the retaining ring 34 to stop the motor 49 and brake at the same time. 56 operates, the cylinder 31 completely stops at a position slightly lower B than the lower limit position, the floating weight 27 reaches the lower limit position, and the material charging port 23 is closed, as shown in FIG.

The stroke S of the weight 27 at this time
Is a distance obtained by subtracting B from the sum of the stroke SC of the cylinder 31 and the stroke SP of the piston 29. Then, the materials are kneaded in the state of FIG. Therefore, with the motor 49 stopped and the brake 56 actuated to stop and fix the cylinder 31, as shown in FIG.
When the control pressure air is supplied to the upper and lower chambers 36 and 38 of the cylinder 31 and kneading is performed while maintaining both chambers 36 and 38 at the same pressure, the floating weight 27 becomes free due to the pressure in the kneading chamber 22. It moves up and down, overload is prevented from occurring, damage to the mechanical device is prevented, the kneading effect is enhanced, and the quality is uniform. It should be noted that the pressing force of the weight 27 can be released for a required time or the pressing force can be adjusted.

When the floating weight 27 is lifted after the kneading of the materials is completed, the brake 56 is opened to start the motor 49 to start the lifting of the cylinder 31, and as shown in FIG. At the same time as the pressure air in the chamber 38 is discharged, the pressure air is supplied to the lower chamber 36 of the cylinder 31 to raise the piston 29, and the floating weight 27 is additionally raised by the piston stroke SP.

When the cylinder 31 reaches the upper limit, the retaining ring 34 activates the upper limit switch 57,
At the same time when the motor 49 is stopped, the brake 56 is activated, the cylinder 31 and the floating weight 27 are stopped at their respective upper limit positions, and the state shown in FIG. 1 is obtained. The present invention is not limited to the above-described embodiment. For example, the cylinder elevating means 33 fixes the screw shaft support 47 to the cylinder head cover 31A, and the screw shaft 48 is rotatably and vertically moved to the upper support plate 32. The screw shaft 48 may be immovably supported to rotate the screw shaft 48 by a motor 49.
Design changes can be made as appropriate.

In the above embodiment, the phase of the kneading rotors is detected during the kneading operation, and the pressing force of the weight 27 is instantly released when the blade tips of the rotors are located at the kneading chamber ends. , When the phase of the peak load of the rotor drive motor reaches a predetermined range, the pressing force of the weight 27 is released for a required time, and further, the load of the rotor drive motor is classified into a plurality of types and detected. Control such as adjusting the pressure of the weight 27 according to the classification
This can be easily performed by controlling the supply and discharge of control air to and from the upper and lower chambers 36, 38 of the cylinder 31.

[0027]

According to the present invention, the free piston is fitted in the cylinder to form the upper chamber and the lower chamber, and the control air can be supplied to and discharged from each chamber individually. The effect can be secured, the overload and damage of the device can be prevented, and the cylinder stroke can be shortened by the piston stroke compared to the conventional device, and the overall height of the device can be reduced (about 20
%, The time required for the entire stroke of the cylinder can be shortened (about 20%), and productivity, kneading effect and quality can be improved (claim 1).

Further, according to the present invention, since the stopper with which the free piston abuts is arranged at the upper end of the hopper, the lower limit of the floating weight can be accurately positioned, and the impact at the lower limit of the cylinder is eliminated ( Claim 2). Further, according to the present invention, since a brake is provided in the lifting means of the cylinder, the cylinder can be stopped accurately and reliably at the upper and lower limits thereof, and the positioning can be fixed, and the cushion effect of the floating weight and the pressure control can be ensured. It is possible (claim 3).

[Brief description of the drawings]

FIG. 1 is a central vertical sectional view showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram of an operating (during descending) state of the same embodiment.

FIG. 3 is a state explanatory view of a lower limit position (during kneading) of the floating weight of the same embodiment.

FIG. 4 is an explanatory diagram of a floating weight control state during material kneading in the same embodiment.

FIG. 5 is an explanatory view of a state in which the floating weight is being raised according to the same embodiment.

FIG. 6 is a schematic configuration diagram showing a conventional example.

FIG. 7 is a cross-sectional view showing a main body of a batch type mixer.

[Explanation of symbols]

 20 Batch Mixer 22 Kneading Chamber 23 Material Inlet 24 Hopper 27 Floating Weight 28 Piston Rod 29 Piston 30 Free Piston 31 Cylinder 33 Elevating Means 34 Locking Ring 36 Lower Chamber 37 Control Air Pipe 38 Upper Chamber 39 Control Air Pipe 42 Stopper 44 Supply / Discharge valve 45 Supply / Discharge valve 56 Brake mechanism

Claims (3)

[Claims] 1. A floating weight for opening and closing the material inlet is provided in a hopper above the material inlet to a kneading chamber of a mixer so as to be vertically movable, and a lower portion which is vertically moved above the weight by an elevating means. An open cylinder is provided, and a vertically movable piston is fitted in the cylinder, and the piston and the floating weight are connected via a piston rod. Between the piston and the free piston, a free piston that is externally fitted to the piston rod and moves up and down is fitted, a piston retaining ring is provided at the lower end of the cylinder, and the upper chamber is formed above the piston of the cylinder. A batch characterized in that a control air pipe having a supply / discharge valve interposed is connected to the lower chamber formed in Mixer of the weight actuating device. 2. The weight operating device for a batch type mixer according to claim 1, wherein a stopper with which a free piston abuts is arranged at an upper end portion of the hopper. 3. The weight operating device for a batch type mixer according to claim 1, wherein a brake mechanism is provided in the lifting means of the cylinder.