JPH10296723A - Cutter hub holder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutter hub holder for an underwater pelletizer, capable of reducing the wear of a cutter blade and of a die plate while variably controlling the pressing force of the cutter hub holder against the die plate to maintain desired operational conditions. SOLUTION: A cutter hub holder 30 for a blade which works on a die plate of an underwater pelletizer is power-transmissively connected to a motor shaft 2 and includes a spring load type blade holder pressed in an axial direction against the die plate 28 by a fluid pressure variably controlled. The power- transmissive connection between the motor shaft 2 and the cutter hub holder 30 is performed by a quickly connecting/disconnecting coupling capable of rapidly disconnecting the blade holder. The motor shaft 2 has a through-hole 9A for introducing the fluid pressure into the cutter hub holder 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to a spring-loaded blade holder, which is motively connected to a drive shaft and is pressed axially toward a die plate with a variably controlled pressure. The present invention relates to a cutter hub holder for a blade acting on a die plate of an underwater pelletizer. The drive connection of the cutter hub holder between the drive shaft and the blade holder includes a quick connect and release drive coupling.

[0002]

BACKGROUND OF THE INVENTION An underwater pelletizer is disclosed in the following U.S. Pat. That is, U.S. Pat. Nos. 3,196,487, 3,317,957, 4,1.
Nos. 23,207, 4,179,255, 4,500,
No. 271, 4,529,370, 4,614,307
No. 4,782,276, 5,059,103,
5,110,523, 5,190,768, 5,4
Nos. 35,713 and 5,527,176.

[0003] The above-mentioned patents describe (a) a device for manually controlling the displacement of the cutter assembly to compensate for blade wear and maintain accurate blade pressure on the die; and (b) a cutter assembly and die. A device for automatically propelling the blade by a step motor activated by a sensor that detects blade wear by detecting the relative distance between: (c) a spring for applying pressure to the knife holder assembly; (D) Disclose an electrical circuit for hydraulic control to automatically displace the drive shaft to control blade pressure on the die. However, the above-mentioned patents describe a structure that provides variable fluid pressure to pistons and cylinders incorporated within a drive shaft and the optimality of a cutter assembly or cutter blade that is directed against a die surface by applying a force to a spring that displaces a cutter hub. It does not disclose an intermediary member that maintains a high pressure. Furthermore, the above-mentioned patent does not disclose a bayonet coupling cutter hub attachment to the drive shaft of a submerged pelletizer that allows relative axial movement.

In a cutter hub holder of the type generally disclosed in US Pat. No. 5,059,103 issued Oct. 22, 1991, wear of the cutter blade is compensated for and the cutter blade is mounted on the die plate. To ensure permanent contact, the cutter hub is pressed against the die plate by a spring. In known cutter hub holders, the spring pressure is selected to meet the needs during the pelletizing process. Therefore, this pressure is always set to the highest pressure required during operation, even if there is a sufficient process with a low spring pressure. The higher the spring pressure acting on the blade holder, the greater the wear of the blade and die plate.

[0005] Devices utilizing the manual adjustment of cutter holders and blades require the careful attention of the operator during operation of the device. As the blade wears,
Pellet quality is reduced and the operator must constantly monitor the process and adjust the blades. The amount of adjustment made will vary from operator to operator. Often they tend to over-adjust, premature blade and die plate wear. The pressure can be set lightly or heavily as required, so that the operator can move one setting without further adjustment required. Compression springs are used in the cutter head to ensure constant contact between the die and the cutter.

Devices utilizing only compression springs for blade adjustment do not offer the freedom to vary the pressure of the cutter blade against the die surface. A spring of the desired tension must be incorporated into the cutterhead during set up. Once the device has been actuated, the spring tension cannot be changed, even if it is heavier or lighter than the required tension. When changing the spring,
All cutting processes must be stopped. With a controllable fluid pressure, as proposed by the present invention, the pressure of the blade on the die can be adjusted to the same lightness or weight required by a simple air pressure regulator.

[0007] Devices that utilize hydraulic pressure to adjust the blade require the use of a dedicated hydraulic unit to control the pressure of the blade against the die. The use of this method to control blade adjustment involves more elements, both mechanically and electrically. In order to house the hydraulic unit, equipment must be provided on or around the device, and a fluid design incorporating an air line is required. In environments incorporating this type of equipment, compressed air lines are generally available. In addition, a specified control circuit is required on the hydraulically adjusted unit for the drive motor on the hydraulic unit. Furthermore, when the hydraulic method is used, special care must be taken to prevent oil from leaking into the treated water even if a seal is defective.

[0008]

It is an object of the present invention to maintain full control of all operating conditions by pressing the holder against the die plate at a controlled variable pressure, preferably using fluid pressure. SUMMARY OF THE INVENTION It is an object of the present invention to provide a cutter hub holder for an underwater pelletizer that can reduce wear of a blade and a die plate.

[0009]

SUMMARY OF THE INVENTION As used herein, a cutter hub holder of the present invention includes a blade holder on which a cutter blade rests, a component interconnecting with the cutter hub, and a component mounted on the cutter hub. A drive shaft of an electric drive motor that rotates with the mounted cutter blade.

According to the present invention, the cutter hub on which the blade is placed is pressed against the die plate with a variable pressure by the cutter hub holder. Therefore, the optimum pressure can always be used according to the operation state. This means that during normal operation, the pelletization takes place at a lower pressure and the blade pressure can be increased for a short period of time in response to the changes occurring during operation.

[0011] High pressures, such as a cutter hub, on an active die plate can be caused, for example, by smearing.
As a result of the ring, it will be required when a polymer layer is formed on the cutting surface of the blade. Such a layer will degrade the cutting performance and the quality of the cut pellet. Thus, the plant must be shut down to remove the polymer, resulting in substantial disconnection and interruption during operation. The cutter hub according to the invention allows the removal of the polymer layer that forms on the cutting surface by increasing the pressure of the blade against the die plate for a short time, and the cutting surface is cleaned. Thus, the product may remain under a slower, lower blade pressure.

In another example, it is necessary to initiate the pelletization of very low viscosity material at the high pressure of the blade against the cutting surface. However, after the extrusion fixation and pelletizing steps, the pressure of the blade against the cutting surface is reduced, and pelletization can be performed at lower pressures that would minimize wear of the blade and die plate.

With the cutter hub holder of the present invention, wear of the blade and cutting surface and / or die plate is inevitable, as the pressure of the holder, and thus the pressure of the blade against the die plate, is adapted to current operating requirements. The amount can be minimized.

According to a preferred embodiment of the present invention, the holder can be hydraulically pressed in the direction of the die plate. Since the fluid pressure is easily controllable, the control equipment can easily and quickly adjust the pressure currently required.

Further according to the invention, a drive shaft such as an electric motor is provided with an axial bore. The axial bore has an end indicating that the cutter hub holder extends to the cylinder bore and an end connected to a source of compressed air by a rotary transmission lead-through. The cylinder bore includes a piston, a piston rod, which is connected to the holder or acts directly on the holder.

[0016] The cutter hub holder is preferably configured as a tubular headpiece which is connected to a shaft which is axially shiftable but not rotatable or a vehicle which is connected to the shaft. The headpiece has a through hole that is stepped with at least two annular shoulders or a pocket hole that is stepped with at least one annular shoulder. In addition, a pressure spring is inserted between the annular shoulder or the bottom of the pocket-like hole outside the through hole and the piston rod. The pressure exerted on this pressure spring can be varied by changing the position of the piston rod, and will thus be suitable for the currently required pressure of the blade against the die plate.

To enable rapid replacement of blades and cutter hubs without long interruptions in operation, the present invention
The headpiece of the cutter hub holder is connected by a bayonet coupling to the shaft or a vehicle connected to the shaft in a power-conducting and separable manner. The bayonet coupling is preferably configured to be associated with a pressure spring. A pressure spring may maintain the bayonet coupling in the locked position.

The bayonet coupling consists of two parallel grooves in the shaft. One groove is open at the end of the shaft. The other groove terminates inward of the end of the shaft, and the grooves are connected to each other at each inner end by a radial circumferential groove. The headpiece includes a key that projects into the hole. The key engages the shaft and is shiftable within a groove in the shaft. The headpiece may be pushed axially on the shaft until the key reaches the inner end of the open end groove, and then rotated into another groove that acts to lock the headpiece against the shaft. , But the axial movement of the headpiece with respect to the shaft is still possible. Preferably, the pressure of the spring is selected to correspond roughly, or is equal to or higher than the maximum pressure of the blade against the die plate. To remove the headpiece, it is only necessary to press the headpiece inward in the same axial direction against the spring and reverse it with respect to the direction of drive rotation. The key can then be pulled out of the open end groove of the bayonet coupling. It is preferable that the key and the groove attaching device are provided as a pair in a region diametrically opposed to the shaft and the headpiece.

[0019]

Preferred embodiments will be described below with reference to the accompanying drawings.
The present invention will be described in more detail, but the present invention is not limited thereto. Other embodiments may be used,
It can be implemented in various ways. Furthermore, in describing the preferred embodiments, certain terms are used only for clarity of the invention. It is to be understood that each specific term includes all technical equivalents that serve in a similar manner to achieve a similar purpose. In the drawings, the same reference numerals are given to indicate the same members.

The cutter hub holder of the underwater pelletizer according to the present invention will be described in a manner substantially similar to that described in US Pat. No. 5,069,103. The cutter hub holder of the present invention is generally designated by the reference numeral 30 and differs from the aforementioned U.S. patent in the features described more fully below.

The motor shaft 1 of the electric drive motor 2 is
A substantially central hole 3 is provided. At the power extraction end of the motor shaft 1, the center hole 3 extends to the cylinder hole 4 via an annular shoulder 4A. The cylinder bore 4 includes a fluid pressure piston 5 connected to a piston rod 6.

The power take-off end of the motor shaft 1 has a tubular medium 7. The rear end of the tubular medium 7 overlaps the motor shaft 1 and extends to a sleeve 8 connected to the motor shaft 1. The vehicle 7 comprises a forward cylindrical part 9 having a smaller diameter than the sleeve 8. This cylindrical portion 9 has a smaller diameter through hole 9A.
Is provided. The through hole 9 </ b> A is substantially aligned with the center hole 3 and the cylinder hole 4 and receives the sliding member 10 mounted on the piston rod 6.

As shown in FIG. 4, the cylindrical portion 9 of the vehicle 7 is provided with an outer groove forming a part of the bayonet coupling and includes an open end groove 12 and a parallel groove 13. Parallel groove 13
Are closed at the outer end. The inner ends of the grooves 12 and 13 are connected to each other by a radial circumferential groove 14. The groove 12 is, as shown by the arrow 15 in FIG.
Is offset with respect to The grooves 12 and 13 are provided by machining on the surface of the cylindrical part 9 substantially parallel to the axis of the cylindrical part 9.

The cylindrical part 9 of the vehicle 7 holds the headpiece 16. The headpiece 16 has a blind hole 1 having an annular shoulder 17 at its inner end, as shown in FIG.
6A constitute a rotationally symmetric part. Headpiece 1
6 receives the cylindrical part 9 in a telescopic manner. The pressure spring 18 is inserted into a blind hole 16A between the slide piece 10 and a substantially central recess 17A forming the shoulder portion 17.

The blind hole 16A of the headpiece 16 has diametrically opposed keys 20. Key 20 is blind hole 1
6A projects radially into 6A and is held in place by welding or the like. The front end of the headpiece 16 has an external thread groove 21. A cutter holder 22 is screwed onto the outer thread groove 21 as shown in FIG.

To place the headpiece 16 on the cylindrical part 9, the key 20 is inserted into the opposing slot or open-end groove 12 and is pushed inward to the bottom of these grooves. Thus, the pressure spring 18 is compressed and the key 2
The 0 can be locked in the groove 13 by shifting in an arcuate manner radially through the circumferential groove 14. further,
The key 20 preferably has a shorter length than the groove 13 that allows the head piece 16 to move in the axial direction, as indicated by an arrow 31 in FIG. The axial movement of the headpiece 16 against the spring 18 causes the cutter hub or blade holder 22 and the cutter blade 23 to move toward the die surface 24, as shown in FIG.

The outer end 25 of the motor shaft 1 is connected to a fixed roller retransmission lead-through (rotary transm.
ission leadthrough) 26. At the fixed rotary transmission lead-through 26, the compressed air line is connected through a pressure regulating valve to detect and control the fluid pressure entering the central hole 3 in the motor shaft 1. A flange 27 mounted on a motor housing, which is basically known from U.S. Pat. No. 5,059,103, serves as a mounting for a water box with water flow and return lines and a die plate 28. Across the die plate 28, the blades 23 of the cutter hub 22 wipe the water.

The quick connection and disconnection of the cutter hub 22, the headpiece 16 and the vehicle 17 is made possible by the slots 12, 14 and 13 cooperating with the key 20.
When the components are in an assembled relationship and it is desired to quickly release the cutter hub 22 after the flange 27 has been separated from the water box and the motor housing and associated structures have been moved away from the die surface, the cutter Applying an axial force on the hub 22 compresses the spring 18 enough to align the key 20 with the groove 14 and simply rotates the cutter hub 22 in a counterclockwise direction indicated by arrow 15 in FIG. Is fine. As soon as the key 20 is aligned with the groove 12, the cutter hub 22 with the headpiece 16 and the vehicle 7 is movable in the axial direction of the cylindrical part 9 until the key 20 exits the groove 12. This quick release function
Without long-term interruption of underwater pelletizer work,
Enables quick replacement of cutter hubs and blades.

To assemble the cutter hub 22, the headpiece 16 and the vehicle 7 on the cylindrical part 9,
It is only necessary to move the assembly axially inward by aligning the 0 with the open end of the groove 12 and compressing the spring 18 until the key 20 is aligned with the groove 14. Next, the cutter hub 22, the headpiece 16 and the vehicle 7 are
Is partially rotated in the clockwise direction until has moved through the groove 14 to a position aligned with the groove 13. At this time, the inward force is released from cutter hub 22 and spring 18 maintains key 20 in groove 13. However, the key 20 is still capable of longitudinal movement in the groove 13 in the axial direction, and as determined by the force of the spring 18 and the fluid pressure exerted on the piston 5, The cutter blade 23 is pressed against the die surface 24. Together with this configuration, the quick connect and disconnect ability of the cutter hub holder 30 allows the cutter hub 22 to be quickly removed and replaced. Further, the displacement of the piston by the controlled fluid pressure is such that the piston 5, the piston rod 6, and the sliding member 10 are controlled and moved by the fluid pressure so as to provide an optimal spring pressure of the blade 23 with respect to the die surface 24. The resiliency of the spring 18, which can compress or release the spring, will change the force pressing the cutter 23 against the die surface 24.

As mentioned above, the cutter hub holder 30 of the present invention provides a cutter hub or blade holder 22.
Are interconnected with the motor shaft 1. These components include a headpiece 16, a spring 18, a sliding member 10, a vehicle 7, a piston rod 6, a piston 5, a cylinder hole 4 having a shoulder 4A, and a vehicle 7.
Including a bayonet coupling between the cylindrical portion 9 of the headpiece 16 and the headpiece 16.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a cutter hub holder and an associated drive assembly.

FIG. 2 is a sectional view of a head piece.

FIG. 3 is an end view of a headpiece.

FIG. 4 is a perspective view of an intermediate portion of the shaft having a groove forming a bayonet coupling.

[Explanation of symbols]

 1: Motor shaft 2: Drive motor 3: Center hole 4: Cylinder hole 5: Piston 6: Piston rod 7: Medium 8: Sleeve 9: Cylindrical portion 10: Sliding member 12, 13, 14: Groove 16: Head Piece 17: Annular shoulder 18: Spring 20: Key 22: Blade holder 23: Cutter blade 24: Die surface 28: Die plate 30: Cutter hub holder

 ──────────────────────────────────────────────────続 き Continued on the front page (71) Applicant 597157783 RFD 2, Box 142, Eagle Rock, Virginia 24085, United States of America

Claims (19)

[Claims] 1. A cutter hub holder for a blade acting in conjunction with a die plate of a submerged pelletizer, wherein the cutter hub holder is power conductively connected to a drive shaft and is axially driven at a variably controlled pressure. A cutter hub holder comprising a spring-loaded blade holder pressed toward the die plate. 2. The cutter hub holder according to claim 1, wherein:
The cutter hub holder, wherein the holder is pressed toward the die plate by a spring, and is pressed by a fluid pressure in the direction of the die plate. 3. The cutter hub holder according to claim 2, wherein the drive shaft has a shaft hole, and one end of the shaft hole of the drive shaft is adjacent to the holder including a cylinder hole. The other end of the shaft hole is connected to a pressurized air source by a rotary transmission lead-through, and the cylinder hole slidably receives a piston and a piston rod acting on a holder via the spring. And cutter hub holder. 4. The cutter hub holder according to claim 1, wherein:
The cutter hub holder, wherein the drive shaft is a shaft of an electric motor. 5. The cutter hub holder of claim 2, wherein said holder is connected to said drive shaft and is power conductively connected to a vehicle axially movable with respect to said drive shaft. The vehicle is configured as a headpiece, the vehicle includes a through-hole extending to receive a piston rod, the spring is engaged between the piston rod and the headpiece, and the vehicle is A cutter hub holder on which the head piece is mounted so as to be movable in an axial direction. 6. The cutter hub holder according to claim 5, wherein
The headpiece is removably mounted on the vehicle in a removable and axially movable manner, and comprises a bayonet coupling for removably mounting the headpiece on the vehicle. Cutter hub holder. 7. The cutter hub holder according to claim 6, wherein the insertion coupling includes a pair of parallel grooves in the medium, and one of the grooves is open at an outer end. The other groove is closed at an outer end, the pair of grooves are connected to each other by a radial groove at an inner end thereof, and the head piece is radially inserted into the hole. Having at least one protruding key that engages the groove in the hole and allows the headpiece to be axially shifted when the key engages the other of the pair of grooves; A cutter hub holder. 8. The cutter hub holder according to claim 7, wherein:
A cutter hub holder, wherein the vehicle includes a pair of diametrically opposed grooves, and a hole in the headpiece includes two keys. 9. A cutter hub holder for a blade acting on a die plate of an underwater pelletizer, the blade hub holder being motively connected to a drive shaft and variably controlled fluid pressure toward the die plate. A cutter hub holder comprising a blade holder pressed in an axial direction. 10. The cutter hub holder according to claim 9, wherein the blade holder is further pressed toward the die plate by a coil spring, and the coil spring rests on the blade holder toward the die plate. A cutter hub holder being hydraulically pressurized with respect to said die plate by a controlled pressure displacement at a given pressure. 11. The cutter hub holder of claim 10 wherein said drive shaft has an axial bore having one end connected to a source of pressurized air controlled by a pressure regulator. The axial bore includes, at opposing ends, a piston and a piston rod slidable within the axial bore and engaging the spring to variably control the blade holder. And cutter hub holder. 12. The cutter hub holder according to claim 11, including a tubular headpiece supporting said blade holder, said tubular headpiece being axially movable with respect to said drive shaft and rotatable by said drive shaft. The spring is positioned in a hole in the headpiece, one end of the spring exerts a force on the headpiece, and the other end is compressed or expanded by the movement of the piston and piston rod. A cutter hub holder characterized by being removed. 13. The cutter hub holder of claim 9, wherein said drive shaft and said blade holder comprise a quick connect / disconnect coupling so that said blade holder can be replaced quickly and easily. Characterized cutter hub holder. 14. The cutter hub holder of claim 13, wherein said quick connect / disconnect coupling includes a bayonet coupling between said blade holder and said drive shaft. 15. A quick connect / disconnect coupling between a blade holder, which is power conductively connected to a drive shaft and is axially pressed toward a die plate of a submerged pelletizer, wherein the blade holder comprises: A quick-connect coupling / disengagement coupling comprising a bayonet coupling of the tubular member having the drive shaft and a quick-connect of the blade holder. Quick connection / disconnection coupling characterized by the ability to easily exchange. 16. The quick connect / disconnect coupling of claim 15, wherein said plug-in coupling includes a power-conducting connection of said plug-in coupling to said tubular member and said drive shaft. A quick connect / disconnect coupling, wherein the tubular member can be moved axially with respect to the drive shaft when the holder can be pressed and moved toward the die plate. 17. The quick connect / disconnect coupling of claim 16, wherein the tubular member includes a vehicle that is power conductive and axially movable with respect to the blade holder, and wherein the drive shaft is variable. A hole communicating with a controlled source of fluid pressure, wherein the vehicle is positioned between a hole in the drive shaft and a hole in the tubular member, and a hole in the tubular member. A shaft that corresponds to a variably controlled fluid pressure introduced into a hole in the drive shaft to engage the spring with the hole and change the pressure exerted on the blade holder by the spring. A quick connect / disconnect coupling comprising a piston to be moved in a direction and a piston rod. 18. The quick connect / disconnect coupling of claim 17, wherein the drive shaft includes a parallel slot having an inner end connected by a circumferential slot, one slot of the drive shaft. An open end communicating with the end, the other slot having a closed outer end inwardly spaced from an end of the drive shaft, and the vehicle includes a key engaged with the slot. Including
When the key of the vehicle is in the closed end slot, the key and the vehicle are movable along the length of the drive shaft, and the vehicle includes a spring in the closed end slot. Inward axial movement of the key to overcome the resistance of the key, rotational movement of the key to a position aligned with the open end slot in a slot connected to the inner end of the parallel slot, and A quick connect / disconnect coupling characterized by being assembled or disassembled with respect to the drive shaft by outward axial movement of the key within the open end slot until exiting the open end slot. 19. An underwater pelletizer having an adjustable cutter hub holder axially movable and power conductively connected between a cutter hub having a mounted cutter blade and a drive shaft. Wherein the drive shaft includes a through hole connected to a variably controlled pressure source for pressing the cutter hub and the cutter blade toward a die plate of the underwater pelletizer. Underwater pelletizer.