JP6765256B2 - Cutter blade pressing control device and method - Google Patents

Description

The present invention relates to a cutter blade pressing control device and method, and more particularly to a novel improvement for controlling the forward / backward movement of a cutter shaft with an electric jack and a hydraulic cylinder.

As a cutter blade control device of this type that has been conventionally used, for example, “Method of correcting the cutter blade pressing pressure in a plastic underwater cutting device” of Patent Document 1 can be mentioned, and although not shown, underwater cutting This is a method in which the position of the cutter blade of the device is detected by a position sensor to detect the amount of wear of the cutter blade, compared with the reference amount of wear, pressure is adjusted based on the comparison result, and cutting is performed at an appropriate pressure.

Further, the forward / backward structure of the cutter shaft used in the above-mentioned underwater cutting device adopts the configuration shown in FIG.
That is, what is indicated by reference numeral 1 in FIG. 3 is a die 1 provided at the most downstream position of the extrusion cylinder 1A, and the strand is extruded from the extrusion hole 1B provided in the die 1. Has been done.

A cutter box 7 configured to circulate the circulating water 8 is attached to the die 1, and a cylinder cover 11 forming a part of the hydraulic cylinder 10 is provided at one end 7b of the cutter box 7. ing.
In the ring-shaped recess 12 formed on the inner surface 11a of the cylinder cover 11, the ring-shaped protrusion 14 of the cylinder body 13 arranged inside the cylinder cover 11 is located.

A pair of bearings 15 and 16 are internally provided inside the tubular body 13, and a cutter box bearing 7a is provided at the center position of the cutter box 7.
A cutter shaft 4 is rotatably provided so as to penetrate the cutter box 7 and the bearings 7a for the cutter box in the cylinder 13 and the bearings 15 and 16, and a cutter holder is provided at the tip 4a of the cutter shaft 4. A plurality of cutter blades 2 are provided via 3.
When the molten resin kneaded and melted in the extrusion cylinder 1A is extruded as a strand through each of the extrusion holes 1B, it is cut into pellets having a predetermined length by the cutter blade 2.

Since the above-mentioned ring-shaped protrusion 14 is located in the ring-shaped recess 12 of the cylinder cover 11, the ring-shaped first and second chambers 12A are located at both sides of the ring-shaped protrusion 14 along the axial direction A. , 12B are formed.
The first chamber 12A is configured so that the first medium 20 such as air can be supplied through the first ventilation hole 5, and the second chamber 12B is configured to be supplied with a second medium such as air through the second ventilation hole 6. It is configured so that the medium 21 can be supplied.

The outer rings 15a and 16a of the bearings 15 and 16 are fitted and connected to the inner surface 13a of the cylinder 13, and the inner rings 15b and 16b of the bearings 15 and 16 are the circumferences of the cutter shaft 4. It is fitted and connected to the surface 14a.
A cutter motor 23 is connected to the rear end 4b of the cutter shaft 4 via a joint 22.

Next, in the above-described configuration, when the cutter motor 23 is rotated to rotate the pair of cutter blades 2 in a state where the molten resin is extruded from the extrusion cylinder 1A as strands, the strands face each other by 180 degrees. As pellets cut to a length corresponding to the rotation speed of each cutter blade 2 arranged, they are supplied into the cutter box 7 and sent together with the circulating water 30 to a well-known pellet drying device (not shown) for drying.

In the hydraulic cylinder 10 described above, by supplying a large amount of the first medium 20 to the first chamber 12A through the first ventilation hole 5, the pressure in the first chamber 12A increases and the volume of the second chamber 12B is increased. The cutter shaft 4 retracts together with the cylinder 13 to reduce the pressure of the cutter blade 2 on the die 1.
Further, contrary to the above, by supplying a large amount of the second medium 21 through the second ventilation hole 6, the pressure in the second chamber 12B increases, the cutter shaft 4 advances, and the die 1 The pressure of the cutter blade 2 on the cutter blade 2 is reduced.

Japanese Unexamined Patent Publication No. 2005-59411

Since the conventional cutter blade control device is configured as described above, the following problems exist.
That is, in the conventional configuration in which the pressure medium is moved forward and backward by increasing or decreasing the pressure medium using air, the pressure fluctuates when the medium is increased or decreased, so that only intermittent control is possible, and rapid continuous control is not possible. Therefore, it is not suitable for automatic control because it is a slow control with a long response time.
Further, in the configuration of Patent Document 1, even if the pressure is adjusted by the pressure medium, the pressure of the pressure medium ≠ the cutter pressure depending on the operating conditions of the apparatus, so that the correction is necessary. Therefore, the amount of wear (shaft). It was necessary to monitor the amount of advancement of the device and determine the correction value, which made the control system complicated.
Further, in the above-mentioned conventional configuration, when the air pressure is constant, an excessive pressure is applied between the die and the cutter blade depending on the operating conditions, and there is a problem that the die and the cutter blade are worn faster.
Further, since the mechanism for advancing / retracting the cutter blade is performed by the air introduced from each ventilation hole, it is necessary to configure an air circuit, and the overall configuration of the apparatus is complicated.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a cutter blade control device and a method in which a cutter shaft is moved forward and backward by an electric jack and a hydraulic cylinder. And.

The cutter blade control device according to the present invention includes a cutter blade provided in a cutter holder of a cutter shaft rotated by a cutter motor, a back-and-forth movement driving means for moving the cutter shaft back and forth with respect to a die along an axial direction. In a cutter blade pressing control device configured to urge the cutter blade against the die via the cutter shaft by the front-back movement driving means, the front-back movement driving means is the cutter shaft. An electric jack provided on the outer ring of the bearing of the hydraulic cylinder that rotatably supports the cylinder, a control unit for inputting a pressure signal of a pressure gauge provided on the hydraulic cylinder, and the above. It consists of a motor provided in the electric jack to which a stroke control signal from the control unit is input, and controls the operation of the electric jack by a stroke control signal output from the control unit based on the pressure signal. The structure is such that the pressing of the cutter blade is controlled via the cutter shaft, and the hydraulic cylinder has a cylinder cover provided in a cutter box fixed to the die and a shaft inside the cylinder cover. A cylinder provided so as to be movable in a direction, a bearing provided between the cylinder and the cutter shaft, a ring-shaped recess formed on the inner surface of the cylinder cover, and projecting to the outer periphery of the cylinder. A ring-shaped protrusion formed in the ring-shaped recess, a closed first and second chambers formed in the ring-shaped recess by the ring-shaped protrusion, and the first and second chambers are preliminarily built in. It is composed of oil and a pressure gauge for detecting the pressure of the hydraulic cylinder, and the pressure gauge is in one or both of the first and second chambers, or the cylinder itself or The cutter blade pressing control method according to the present invention has a configuration provided in the vicinity, and the cutter blade provided in the cutter holder of the cutter shaft rotated by the cutter motor and the cutter shaft are dies along the axial direction. Pressing control of the cutter blade by using the back-and-forth movement driving means for moving back and forth with respect to the cutter blade so as to urge the cutter blade against the die via the cutter shaft. In the method, the front-rear movement driving means includes an electric jack for pressing a cylinder provided on an outer ring of a bearing of a hydraulic cylinder that rotatably supports the cutter shaft, and a pressure gauge provided on the hydraulic cylinder. The control unit for inputting the pressure signal of The cutter is composed of a motor provided in the jack to which a stroke control signal from the control unit is input, and controls the operation of the electric jack by a stroke control signal output from the control unit based on the pressure signal. It is a method of controlling the pressing of the cutter blade via a shaft, and the hydraulic cylinder can be moved axially inside the cylinder cover and a cylinder cover provided in a cutter box fixed to the die. The cylinder provided, the bearing provided between the cylinder and the cutter shaft, the ring-shaped recess formed on the inner surface of the cylinder cover, and the ring-shaped recess formed on the outer periphery of the cylinder. The ring-shaped protrusions located in the recesses, the sealed first and second chambers formed in the ring-shaped recesses by the ring-shaped protrusions, the oil preliminarily incorporated in the first and second chambers, and the above. It is a method including a pressure gauge for detecting the pressure of a hydraulic cylinder, and the pressure gauge is provided in one or both of the first and second chambers, or in or near the cylinder itself. This is the method.

Since the cutter blade pressing control device and method according to the present invention are configured as described above, the following effects can be obtained.
That is, since the operating amount of the electric jack corresponds to the advancing amount, the same correction is possible and continuous control is possible. Therefore, the cutter blade can be stored in advance by storing the parameters according to the operating conditions in the control device. Full automation of the control device can be achieved.
Further, since the structure can be simplified, the manufacturing cost can be suppressed, and the maintenance cost and time can be reduced.
Further, since an appropriate pressing force can be maintained at all times, wear of the cutter blade and the die can be suppressed.
Further, since the wear of the cutter blade and the die can be suppressed, the life of the cutter blade and the die can be extended.
Further, by extending the life of the cutter blade and the die, the maintenance cost time can be reduced.
Further, since the pressing adjustment can be automatically performed, the alignment according to the operating conditions, which has been conventionally required, becomes unnecessary.
Further, by providing the safety valve in the hydraulic unit, it is possible to prevent the motor from being damaged due to the sudden retreat of the cutter blade in the event of a trouble.

It is a schematic block diagram which shows the pressing control device and method of a cutter blade by this invention. It is the schematic sectional drawing of the hydraulic cylinder of FIG. It is the schematic sectional drawing which shows the pressing control device of the conventional cutter blade.

The cutter blade pressing control device and method according to the present invention is to automatically control the pressing of the cutter blade against the die with a simple configuration by performing the forward / backward movement of the cutter shaft with an electric jack and a hydraulic cylinder.

Hereinafter, preferred embodiments of the cutter blade pressing control device and method according to the present invention will be described with reference to the drawings.
The same or equivalent parts as those of the conventional example will be described with the same reference numerals.
FIG. 1 is a configuration diagram showing an outline of a cutter blade pressing control device according to the present invention. A cutter holder 3 arranged to face a die 1 is provided with a pair of cutter blades 2, and the cutter holder 3 is provided with a cutter motor. A cutter shaft 4 driven by 23 is connected.

A hydraulic cylinder 10 is in contact with the cutter shaft 4, and a rod 42 of an electric jack 41 driven by a motor 40 is in contact with the hydraulic cylinder 10.
The rod 42 is provided on a well-known electric jack 41, and is configured to be able to expand and contract by rotating either forward or reverse of the motor 40.
A pressure made of a well-known strain gauge or the like on any of the first and second chambers 12A and 12B of the hydraulic cylinder 10, any of the surfaces of the cylinder 13, or the surface of the cutter shaft 4. A total of 50 are provided.
The pressure signal 50a obtained from the pressure gauge 50 is input to the control unit 60 made of a personal computer or the like, and the stroke control signal 60a output from the control unit 60 based on the level of the pressure signal 50a is sent to the motor 40. It is configured so that it is input and feedback control is performed using the pressure signal 50a.
An electric jack 41 for pressing the cylinder body 13 provided on the outer rings 15a and 16a of the bearings 15 and 16 of the hydraulic cylinder 10 that rotatably supports the cutter shaft 4 and the hydraulic cylinder 10 are provided. It is composed of a control unit 60 for inputting a pressure signal of the pressure gauge 50 and a motor 40 provided on the electric jack 41 to which a stroke control signal 60a from the control unit 60 is input.

FIG. 2 is a configuration showing the internal configuration of the hydraulic cylinder 10 in FIG. 1 in a concrete and enlarged manner.
What is indicated by reference numeral 1 in FIG. 2 is a die provided at the most downstream position of the extrusion cylinder 1A, and the molten resin is extruded as a strand from the extrusion hole 1B provided in the die. ing.

A cutter box 7 configured to circulate the circulating water 8 is attached to the die 1, and a cylinder cover 11 forming a part of the hydraulic cylinder 10 is provided at one end 7B of the cutter box 7. ing.
In the ring-shaped recess 12 formed on the inner surface 11a of the cylinder cover 11, the ring-shaped protrusion 14 of the cylinder body 13 which is arranged inside the cylinder cover 11 and can move back and forth along the axial direction A is located. ing.

A pair of bearings 15 and 16 are internally provided inside the tubular body 13, and a cutter box bearing 7a is provided at the center position of the cutter box 7.
A cutter shaft 4 is rotatably provided so as to penetrate the cutter box 7 and the bearings 7a for the cutter box in the cylinder 13 and the bearings 15 and 16, and a cutter holder is provided at the tip 4a of the cutter shaft 4. A plurality of cutter blades 2 are provided via 3.
The strand (not shown) extruded from the extrusion hole 1B after being kneaded and melted in the extrusion cylinder 1A is cut and processed into pellets having a predetermined length by the cutter blade 2.

Since the above-mentioned ring-shaped protrusion 14 is located in the ring-shaped recess 12 of the cylinder cover 11, the ring-shaped first and second chambers 12A are located at both sides of the ring-shaped protrusion 14 along the axial direction A. , 12B are formed.
Oil is injected into the first and second chambers 12A and 12B in advance through a valve (not shown) provided on the cylinder cover 11, and the valve is closed so that the chambers 12A and 12B are closed. It is kept in a sealed state.

The outer rings 15a and 16a of the bearings 15 and 16 are fitted and connected to the inner surface 13a of the cylinder 13, and the inner rings 15b and 16b of the bearings 15 and 16 are the circumferences of the cutter shaft 4. It is fitted and connected to the surface 14a.
A cutter motor 23 is connected to the rear end 4b of the cutter shaft 4 via a joint 22.
A pressure gauge 50 is provided in any one or both of the first and second chambers 12A and 12B of the hydraulic cylinder 10, or in or near the cylinder 13 itself, and the pressure gauge 50 is the same. It is configured so that the pressure of the back-and-forth movement along the axial direction A of the cylinder body 13 inside the cylinder cover 11 can be detected. The pressure gauge 50 for detecting the pressing of the hydraulic cylinder 10 is shown in FIG. 2 as a configuration arranged outside the hydraulic cylinder 10, and the pressing of the hydraulic cylinder 10 detected from the pressure gauge 50, that is, The pressure signal 50a indicating the pressure is input to the control unit 60.

Next, the operation of the cutter blade pressing control device and method according to the above configuration will be described.
Under a state in which the cutter motor 23 is rotated, the cutter blade 2 is rotated at a predetermined rotation speed via the cutter shaft 4, and the strands pressed from the extrusion holes 1B are cut into pellets (not shown). The rod of the electric jack 41 is generated by the stroke control signal 60a from the control unit 60, which is output in comparison with the preset value set in the control unit 60 based on the pressure signal 50a detected by the pressure gauge 50. By controlling the expansion and contraction of the 42 and moving it back and forth, the cylinder body 13 of the hydraulic cylinder 10 is moved back and forth to control the pressing.

Further, the pressing force by the electric jack 41 is transmitted to the cutter shaft 4 via the hydraulic cylinder 10, and the pressing of the cutter shaft 4 causes each cutter blade 3 to rotate through the cutter holder 3 to the die 1. Be pressed.
The pressing value is detected by a pressure gauge 50 provided on the hydraulic cylinder 10, and a pressure signal 50a (corresponding to the pressing value described above) of the pressure gauge 50 is input to the control unit 60.

The control unit 60 sets a pressure signal 50a (current pressure value) detected by the pressure gauge 50 in order to match the pressure of the cutter blade 2 against the die 1 with a preset optimum pressure. Based on this, the rod 42 of the electric jack 41 is moved back and forth (corresponding to so-called feedback control using the pressure signal 50a) to control the set pressure.
Since the feedback control is continuously performed unlike the intermittent control of the above-mentioned conventional example, for example, the pressing can be automatically adjusted to the set value and maintained according to the driving situation.
Therefore, if the control unit 60 sets the optimum set pressure for various resins in advance and stores the data in, for example, a well-known look-up table (not shown), the pressure can be controlled for each set value. It can be done continuously.

The gist of the cutter blade pressing control device and method according to the present invention is as follows.
That is, the cutter blade 2 provided in the cutter holder 3 of the cutter shaft 4 rotated by the cutter motor 23, and the back-and-forth movement driving means 100 for moving the cutter shaft 4 back and forth with respect to the die 1 along the axial direction A. In a cutter blade pressing control device configured to urge the cutter blade 2 against the die 1 via the cutter shaft 4 by the front-back movement driving means 100, the front-back movement driving means. Reference numeral 100 denotes an electric jack 41 for pressing the cylinder body 13 provided on the outer rings 15a and 16a of the bearings 15 and 16 of the hydraulic cylinder 10 that rotatably supports the cutter shaft 4, and the hydraulic cylinder 10. The pressure signal is composed of a control unit 60 for inputting a pressure signal 50a of the pressure gauge 50, and a motor 40 provided on the electric jack 41 to which a stroke control signal 60a from the control unit 60 is input. With a configuration and method in which the operation of the electric jack 41 is controlled by the stroke control signal 60a output from the control unit 60 based on 50a, and the pressing of the cutter blade 2 is controlled via the cutter shaft 4. The hydraulic cylinder 10 includes a cylinder cover 11 provided in the cutter box 7 fixed to the die 1, and a cylinder body 13 provided inside the cylinder cover 11 so as to be movable in the axial direction A. The bearings 15 and 16 provided between the cylinder 13 and the cutter shaft 4, the ring-shaped recess 12 formed on the inner surface 11a of the cylinder cover 11, and the annular recess 12 formed so as to project from the outer periphery of the cylinder 13. A ring-shaped protrusion 14 located in the ring-shaped recess 12, a sealed first and second chambers 12A and 12B formed in the ring-shaped recess 12 by the ring-shaped protrusion 14, and the first and second chambers. It is a configuration and a method including oil preliminarily built in 12A and 12B and a pressure gauge 50 for detecting the pressure of the hydraulic cylinder 10, and the pressure gauge 50 is the first and second pressure gauges. The configuration and method are provided in one or both of the chambers 12A and 12B, or in or near the cylinder 13 itself.

In the cutter blade pressing control device and method according to the present invention, the cutter shaft having a cutter holder is continuously and automatically pushed and pulled by a closed circuit hydraulic cylinder pushed by an electric jack to make the pressing variable. As a result, wear of the cutter blade and the die can be suppressed, and the life of the cutter blade and the die can be extended.

1 Die 2 Cutter blade 3 Cutter holder 4 Cutter shaft 4a Tip 4b Rear end A Axial direction 1A Extrusion cylinder 1B Extrusion hole 7 Cutter box 7a Cutter box bearing 10 Hydraulic cylinder 11 Cylinder cover 11a Inner surface 12 Ring-shaped recess 12A 1st chamber 12B 2nd Chambers 15,16 Bearings 15a, 16a Outer ring 15b, 16b Inner ring 23 Cutter motor 30 Circulating water 40 Motor (servo motor)
41 Electric jack 50 Pressure gauge 50a Pressure signal 60 Control unit 60a Stroke control signal 100 Forward / backward driving means

Claims (6)

The cutter blade (2) provided on the cutter holder (3) of the cutter shaft (4) rotated by the cutter motor (23) and the cutter shaft (4) with respect to the die (1) along the axial direction (A). Equipped with a back-and-forth movement driving means (100) for moving back and forth
In the cutter blade pressing control device configured to urge the cutter blade (2) against the die (1) via the cutter shaft (4) by the back-and-forth movement driving means (100).
The front-back driving means (100) is a cylinder (13) provided on an outer ring (15a, 16a) of a bearing (15, 16) of a hydraulic cylinder (10) that rotatably supports the cutter shaft (4). ), A control unit (60) for inputting a pressure signal (50a) of a pressure gauge (50) provided on the hydraulic cylinder (10), and the electric jack (60) for pressing the electric jack (41). It consists of a motor (40) provided in 41) and to which a stroke control signal (60a) from the control unit (60) is input.
The operation of the electric jack (41) is controlled by the stroke control signal (60a) output from the control unit (60) based on the pressure signal (50a), and the cutter blade is controlled via the cutter shaft (4). A pressure control device for a cutter blade, which is configured to control the pressure of (2). The hydraulic cylinder (10) is movable in the axial direction (A) inside the cylinder cover (11) provided in the cutter box (7) fixed to the die (1) and the cylinder cover (11). The cylinder body (13) provided, the bearings (15, 16) provided between the cylinder body (13) and the cutter shaft (4), and the inner surface (11a) of the cylinder cover (11). The ring-shaped recess (12) formed in the cylinder, the ring-shaped protrusion (14) formed protruding from the outer periphery of the cylinder (13) and located in the ring-shaped recess (12), and the ring-shaped protrusion (14). Sealed first and second chambers (12A, 12B) formed in the ring-shaped recess (12), oil preliminarily built in the first and second chambers (12A, 12B), and the hydraulic pressure. The cutter blade pressing control device according to claim 1, further comprising a pressure gauge (50) for detecting the pressing of the cylinder (10). The claim is characterized in that the pressure gauge (50) is provided in one or both of the first and second chambers (12A, 12B), or in or near the cylinder (13) itself. 2. The cutter blade pressing control device according to 2. The cutter blade (2) provided on the cutter holder (3) of the cutter shaft (4) rotated by the cutter motor (23) and the cutter shaft (4) with respect to the die (1) along the axial direction (A). Using the back-and-forth movement driving means (100) for moving back and forth.
In the method of pressing the cutter blade in which the cutter blade (2) is urged against the die (1) via the cutter shaft (4) by the back-and-forth movement driving means (100).
The front-back driving means (100) is a cylinder (13) provided on an outer ring (15a, 16a) of a bearing (15, 16) of a hydraulic cylinder (10) that rotatably supports the cutter shaft (4). ), A control unit (60) for inputting a pressure signal (50a) of a pressure gauge (50) provided on the hydraulic cylinder (10), and the electric jack (60) for pressing the electric jack (41). It consists of a motor (40) provided in 41) and to which a stroke control signal (60a) from the control unit (60) is input.
The operation of the electric jack (41) is controlled by the stroke control signal (60a) output from the control unit (60) based on the pressure signal (50a), and the cutter blade is controlled via the cutter shaft (4). (2) A method of controlling the pressure of the cutter blade, which is characterized in that the pressure of the cutter blade is controlled. The hydraulic cylinder (10) is movable in the axial direction (A) inside the cylinder cover (11) provided in the cutter box (7) fixed to the die (1) and the cylinder cover (11). The cylinder body (13) provided, the bearings (15, 16) provided between the cylinder body (13) and the cutter shaft (4), and the inner surface (11a) of the cylinder cover (11). The ring-shaped recess (12) formed in the cylinder, the ring-shaped protrusion (14) formed protruding from the outer periphery of the cylinder (13) and located in the ring-shaped recess (12), and the ring-shaped protrusion (14). Sealed first and second chambers (12A, 12B) formed in the ring-shaped recess (12), oil preliminarily built in the first and second chambers (12A, 12B), and the hydraulic pressure. The method for controlling the pressure of a cutter blade according to claim 4, further comprising a pressure gauge (50) for detecting the pressure of the cylinder (10). The claim is characterized in that the pressure gauge (50) is provided in one or both of the first and second chambers (12A, 12B), or in or near the cylinder (13) itself. 5. The cutter blade pressing control method according to 5.

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