Hopper and grain cutter provided with the same

Abstract

To provide a hopper capable of simultaneously realizing weight reduction and the suppression of reverberation caused by scattering and collision of objects to be processed.SOLUTION: A hopper 20 is provided to feed the resin formed material, which generates when performing resin molding, into a processing device. A wall 21 surrounding the outer periphery is formed using a plate material made of metal, and an opening is provided at the top to serve as an inlet 22 for the resin formed material. At least a left wall 21a and a right wall 21b of the wall 21 are provided with a sound-reducing plate 24 for suppressing reverberation which generates when the resin formed material scatters and hits the plate during the processing.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a hopper and a granulator including the hopper.

Background Art

[0002] When performing resin molding exemplified by injection molding or the like, spools, runners, etc., which are resin formations that become unnecessary, are generated separately from the molded product that becomes the product. By crushing these, recycling, that is, the possibility of reuse as a resin molding material (or for other uses) can arise.

[0003] In particular, the applicant has been engaged in the research and development of a granulator having features not found in conventional crushers as a processing device for resin formations that enables suitable reuse as a resin molding material, and has a background of providing it to the market (see Patent Document 1: Japanese Patent No. 3098658, Patent Document 2: Japanese Patent No. 3108384).

[0004] Here, the "granulator" is a processing device aimed at granulating unnecessary resin formations into a uniform size of grains so that they can be suitably reused. It is different from a processing device that simply crushes resin formations using a rotating crushing blade like a conventional "crusher". It meshes a fixed granulating blade having a shearing blade with a movable granulating blade, and performs a granulating process by bringing the movable granulating blade into contact with and separating from the fixed granulating blade. Since the size of the grains of the processed material can be made uniform, there is an advantage that the granulated material obtained by granulating the resin formation can be suitably reused particularly as a raw material (resin molding material). The method of shearing and granulating the object to be processed in this way is basically different from the method of the conventional crusher.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

[0006] In both the granulator and the crusher, a configuration having a hopper having an inlet for feeding the resin material to be processed is preferable. When the type of resin is changed, for example, this hopper needs to be removed from the processing device and cleaned so that the old resin is not mixed in. Therefore, from the viewpoint of reducing the burden on the worker and preventing accidents, it is important to form it as light as possible.

[0007] Recently, with the improvement of material processing technology such as laser welding, it has become possible to use thin metal materials (for example, 0.8mm or 1.0mm thick) that were previously difficult to use due to the occurrence of waviness, etc. This has resulted in the weight reduction of the hopper.

[0008] However, on the other hand, it has become clear that when a hopper is constructed using a metal material with a thin plate thickness, a new problem occurs in that when the resin formed material is processed (crushed, etc.) in the processing equipment, the resin formed material is likely to fly off and collide with the plate surface of the wall, generating a loud reverberating noise. [Means for solving the problem]

[0009] The present invention has been made in consideration of the above circumstances, and aims to provide a hopper that can simultaneously achieve weight reduction and suppression of reverberation caused by the scattering and collision of the workpiece (resin molding).

[0010] In one embodiment, the above problem is solved by the solution means disclosed below.

[0011] A hopper in one embodiment is a hopper provided for feeding a resin formed material produced during resin molding into a processing device, and has a wall portion surrounding the outer periphery formed using a plate material made of a metal material and an opening at the top for feeding the resin formed material, with a requirement that at least the left and right wall portions of the wall portion have a sound-reducing plate attached thereto to suppress reverberation generated when the resin formed material scatters during processing and hits the plate surface.

[0012] The silent plate is preferably formed using a metal plate material so as to have a thickness greater than the thickness of the wall portion to which it is attached.

[0013] It is also preferable that the silent plate is attached so as to include a position in the vicinity of the opening.

[0014] In addition, it is preferable that the upper wall portion and the rear wall portion of the wall portion are connected via a chamfered inclined wall portion, and that the silent plate is not affixed to the upper wall portion, the rear wall portion, and the inclined wall portion.

[0015] In addition, the granulator according to one embodiment is a granulator as the processing device with the hopper attached to the upper part of the main body, and the main body includes a rotary crushing blade for roughly crushing the resin-formed material fed through the hopper, a fixed crushing blade with a plurality of small shear blades arranged side by side below the rotary crushing blade, and a movable crushing blade with a plurality of shear blades arranged side by side by reciprocating drive to mesh with the fixed crushing blade and to granulate the resin-formed material roughly crushed by the rotary crushing blade. It is also preferable that the lower end of the hopper and the upper end of the rotary crushing blade are arranged so as to be within a distance of +10 mm to -10 mm. Effect of the Invention

[0016] According to the disclosed hopper, it is possible to simultaneously achieve weight reduction and suppression of reverberation caused by scattering and collision of the workpieces. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a perspective view illustrating an example of a grain cutter according to an embodiment of the present invention. [Diagram 2] FIG. 1 is a perspective view illustrating an example of a grain cutter according to an embodiment of the present invention. [Diagram 3] FIG. 2 is a perspective view showing an example of a main body of the granulator shown in FIG. [Figure 4] 4 is a perspective view showing a state in which a movable side panel of the main body shown in FIG. 3 is opened. [Diagram 5] 4 is a cross-sectional view of the main body shown in FIG. 3 taken along line VV. [Figure 6] FIG. 2 is a perspective view illustrating an example of a hopper according to an embodiment of the present invention. [Figure 7] FIG. 2 is a perspective view illustrating an example of a hopper according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The hopper 20 according to this embodiment is a mechanism for feeding a resin formed object (processing object) such as a spool, a runner, etc., into a processing device (a granulator, a crusher, etc.). The processing device will be described using a granulator 1 as an example, but is not limited to this. Note that the resin formed object to be processed in the processing device is usually mainly assumed to be a spool or a runner generated during resin molding such as injection molding, but molded products corresponding to prototypes, defects, surplus, etc. can also be used.

[0019] Here, FIG. 1 is a schematic diagram (oblique view from above the left front) showing an example of the granulator 1 according to this embodiment. FIG. 2 is a schematic diagram (oblique view from above the right rear) showing an example of the granulator 1 shown in FIG. 1. FIG. 3 is a schematic diagram (oblique view from above the left front) showing an example of the main body 40 of the granulator 1 shown in FIG. 1. FIG. 4 is a perspective view showing the state in which the movable side plates 53, 54 of the main body 40 shown in FIG. 3 are opened. FIG. 5 is a cross-sectional view of the main body 40 shown in FIG. 3 along line VV. For convenience of explanation, arrows may be used in the drawings to indicate the up-down, left-right, and front-back directions. In all the drawings for explaining the embodiment, the same reference numerals are used for members having the same functions, and repeated explanations thereof may be omitted.

[0020] As shown in Figures 1 and 2, the granulator 1 according to this embodiment includes a main body 40, a support frame 48 that supports the main body 40, a hopper 20 that is attached to the top of the main body 40 and into which the material to be treated is fed, a chute 44 that is attached to the bottom of the main body 40 and discharges the material to be treated (cut granules), and an electric motor 46 that drives a movable granule cutter blade 60 (described below). The material to be treated is fed into the main body 40 via the hopper 20 above, cut into granules by the main body 40, and drops downward from the chute 44. A paper bag for storing the cut granules can be attached to the chute 44.

[0021] As shown in Figs. 3 to 5, the main body 40 is surrounded on all four sides by the opposing fixed side plates 50, 51 and the opposing movable side plates 53, 54, and is configured with a bottom plate 56. The movable side plates 53, 54 are supported by the fixed side plates 51 and 50 with a shaft (not shown) provided at the lower end, and are attached so as to be openable and closable. By making the movable side plates 53, 54 openable and closable, it is possible to replace the movable grain cutting blade 60 described later. In addition, it is also possible to easily perform maintenance such as cleaning the inside of the main body 40 and observing the grain cutting state of the material to be processed. The reference numeral 55 in the figure denotes a manual knob for attaching the movable side plates 53, 54. The movable side plates 53, 54 can be opened and closed at any time by operating the knob 55. In addition, the bottom plate 56 is provided with a discharge hole 56a through which the grains are passed.

[0022] Inside the main body 40, there are provided a rotary crushing blade 12 and a fixed blade 14 for roughly pre-crushing the material to be treated (sometimes referred to as "coarse crushing"), and a particle cutting blade (a movable particle cutting blade 60 and a fixed particle cutting blade 70, described below) for cutting the roughly crushed material into particles. The particle cutting blades (the movable particle cutting blade 60 and the fixed particle cutting blade 70) are disposed below the rotary crushing blade 12. The rotary crushing blade 12 is configured with a plurality of small blades provided on the shaft 10. The movable particle cutting blade 60 is configured with a plurality of small shear blades arranged in a row parallel to the axis of the swinging shaft 16.

[0023] More specifically, the shaft 10 and the oscillating shaft 16 are suspended between a fixed side plate 50 and a fixed side plate 51 that constitute one opposing side surface of the main body 40, and are rotatable about their respective axes. The shaft 10 and the oscillating shaft 16 are arranged in parallel to each other. The shaft 10 is provided with a rotary crushing blade 12, and the oscillating shaft 16 is provided with a movable grain-cutting blade 60. The movable side plates 53 and 54 that constitute the other opposing side surface of the main body 40 are provided with a fixed blade 14 that meshes with the rotary crushing blade 12 on one side (movable side plate 53), and a fixed grain-cutting blade 70 that meshes with the movable grain-cutting blade 60 on the other side (movable side plate 54).

[0024] In this configuration, an electric motor 46 drives the rotary crushing blade 12 to rotate (in the direction of arrow A) and drives the movable grain cutting blade 60 to swing (in the direction of arrow B) via a conversion mechanism (not shown). As a result, the movable grain cutting blade 60 supported by the swing shaft 16 swings toward and away from the fixed grain cutting blade 70, that is, so as to approach (contact) and move away from the fixed grain cutting blade 70. Therefore, as in conventional grain cutting machines (see Patent Documents 1 and 2), the movable grain cutting blade 60 and the fixed grain cutting blade 70 mesh with each other to cut the material to be processed.

[0025] In this embodiment, the position where the blade surface of the rotary crushing blade 12 passes and the position where the movable grain cutting blade 60 and the fixed grain cutting blade 70 perform grain cutting are arranged close to each other so that the material remaining after grain cutting can be picked up again by the rotary crushing blade 12. With this configuration, the material fed into the main body 40 is first roughly crushed by the rotary crushing blade 12 and the fixed blade 14 inside the main body 40, then falls below the main body 40 and is cut into grains by the movable grain cutting blade 60 and the fixed grain cutting blade 70.

[0026] According to the research of the present inventor, it was found that, compared with the conventional crusher, the granulator 1 having the above-mentioned characteristic configuration needs to perform a coarse crushing process as a process prior to granulation, and scattering of the treated material and collision with the wall part 21 of the hopper 20 are likely to occur due to the arrangement and operation of the rotary crushing blade 12. More specifically, as an example of the arrangement of the rotary crushing blade 12, the lower end of the hopper 20 attached to the main body 40 and the upper end of the rotary crushing blade 12 provided in the main body 40 are arranged so as to be at a distance of +10 mm to -10 mm (in the case of a negative value, the upper end is arranged to protrude from the upper part of the main body 40 and enter the lower part of the hopper 20). Thus, in the granulator 1, the rotary crushing blade 12 is arranged at a position very close to the hopper 20 compared to the conventional crusher. Therefore, it is considered that scattering of the treated material and collision with the wall part 21 of the hopper 20 are likely to occur in the coarse crushing process using the rotary crushing blade 12. In other words, the scattering and reverberation caused by the collision of the workpieces is a problem that can occur more significantly due to the unique configuration of the granulator 1.

[0027] Next, the hopper 20 according to the present embodiment that can solve the above problems will be described in detail. Here, Fig. 6 is a schematic diagram (perspective view from below the left front part) showing an example of the hopper 20 according to the present embodiment. Also, Fig. 7 is a schematic diagram (perspective view from above the right rear part) showing an example of the hopper 20 shown in Fig. 6.

[0028] As shown in Figs. 6 and 7, the hopper 20 according to this embodiment has a wall 21 surrounding the outer periphery, which is formed using a plate material made of a metal material (for example, SUS material, SPCC material, etc.). An opening serving as the inlet 22 for the material to be treated is provided at the top, and an opening serving as the outlet 23 for sending the material to the main body 40 is provided at the bottom, so that the entire hopper 20 is formed in a substantially cylindrical shape. The wall 21 includes a left wall 21a, a right wall 21b, a front wall 21c, a rear wall 21d, an upper wall 21e, and an inclined wall 21f described below. In addition, a resin sheet-like curtain 26 (see Fig. 1) is installed to prevent the material to be treated from flying out of the inlet 22 during operation of the device (granulator 1).

[0029] The wall 21 is constructed by laser welding (connecting) a thin metal material (for example, about 0.8 mm or 1.0 mm thick), which was difficult to use in the past due to the occurrence of wavy patterns. This allows the hopper 20 to be lighter (for example, 30% lighter than in the past), reducing the burden on the worker when removing it from the granulator 1 for cleaning and preventing accidents. However, as described above, a new problem has arisen in that, due to the use of a thin metal material, when the granulator 1 processes (cuts) the workpiece, the workpiece scatters from inside the main body 40 toward the hopper 20 and collides with the plate surface (inner surface) of the wall 21, causing the reverberation sound to become even louder.

[0030] The hopper 20 according to the present embodiment is provided with the following configuration to solve this problem. Specifically, at least the left wall 21a and the right wall 21b of the wall 21 are provided with silent plates 24 (24a) and 24 (24b), which suppress the reverberation generated when the workpiece scatters during processing and hits the plate surface. This is because the effect of suppressing reverberation can be enhanced by attaching the silent plate 24 to the wall 21 having a larger structural area. Therefore, in this embodiment, the silent plate 24 (24c) is also attached to the front wall 21c having a relatively large structural area. Note that, as an example of the method of attachment, "adhesion" is used, but other methods such as "welding" may also be used. In a demonstration experiment conducted by the present inventor, it was confirmed that the reverberation could be significantly suppressed before and after the silent plate 24 was attached to the wall 21. In other words, it has become possible to simultaneously achieve the conflicting goals of weight reduction and reverberation suppression in the hopper 20.

[0031] As an example, the sound-reducing plate 24 is formed using a plate material made of a metal material. The material is not particularly limited, but if the same material as the wall portion 21 is used, a sense of unity can be created in terms of the design of the exterior. The shape is also not particularly limited, but the larger the area, the better the suppression of reverberation.

[0032] The inventors have further researched and have determined the configuration of the silent plate 24 that can further enhance the reverberation suppression effect. First, it is preferable that the silent plate 24 is configured to have a thickness greater than that of the wall 21 to which it is attached. With this configuration, by attaching the silent plate 24 made of a plate material with a different thickness from that of the wall 21, i.e., a different natural frequency, it is possible to obtain the effect of changing the vibration of the wall 21, and as a result, it is believed that the reverberation suppression effect is enhanced.

[0033] Secondly, it is preferable that the sound-absorbing plate 24 is attached so as to include a position near the opening (inlet 22 in this embodiment). Here, "near the opening" in this application is defined as within 1 / 3 of the area on the upper side (i.e., the opening side) of the wall 21 (left wall 21a, right wall 21b, and front wall 21c in this embodiment) and within 1 / 3 of the area on the opening side of the upper wall 21e. It is considered that the end on the opening (inlet 22) side is a free end (or a structure similar thereto) and that reverberation is easily amplified and dissipated, and it is considered that the effect of suppressing reverberation is enhanced by attaching the sound-absorbing plate 24 to a position near the opening (inlet 22).

[0034] In a demonstration experiment conducted by the present inventor, it was confirmed that the effect of suppressing reverberation was further improved in either the first or second configuration described above.

[0035] As described above, by attaching the silent plate 24 to the wall 21, the effect of suppressing reverberation can be obtained, and therefore the silent plate 24 may be attached not only to the left wall 21a, the right wall 21b, and the front wall 21c, but also to the rear wall 21d and the upper wall 21e. On the other hand, the more the number of places to which the silent plate 24 is attached increases, the more complicated the manufacturing process becomes and the longer the tact time becomes. Therefore, in this embodiment, the rear wall 21d and the upper wall 21e are connected via the inclined wall 21f that is chamfered, but the silent plate 24 is not attached to the rear wall 21d, the upper wall 21e, and the inclined wall 21f. In this way, for example, by configuring the rear wall 21d and the upper wall 21e to be connected via the inclined wall 21f, it has been confirmed that the effect of suppressing reverberation can be obtained even if the silent plate 24 is not attached to the plate surface of the wall 21. This is believed to be a synergistic effect of the reduction in each component area due to the multifaceted structure and the improvement in connection strength. However, the inclined wall portion 21f may not be provided.

[0036] Finally, an example of a demonstration experiment carried out by the inventor is shown below. As a test method, a target hopper was placed on the floor, and a glass ball was allowed to fall freely from a position of a predetermined height (set at 500 mm from the impact point) to impact the impact point (set at the central region of the target surface) of the measurement target surface, and the peak sound pressure and frequency at the time of impact were measured at a position of a predetermined distance (set at 1 m from the side of the hopper and 1 m above the floor) (5 consecutive measurements were carried out, and the peak values ​​were recorded). Note that the test in which the measurement target surface was set to the plate surface of the front wall (simply referred to as the "front surface") (however, the impact point was set to the exposed surface on the inlet side) was set as "Test A", and the test in which the measurement target surface was set to the plate surface of the upper wall (simply referred to as the "upper surface") was set as "Test B", and the test results for each are shown in Tables 1 and 2 below.

[0037] [Table 1]

[0038] [Table 2]

[0039] From the above test results, it was confirmed that the hopper according to this embodiment can reduce the peak sound pressure by about 4 to 7% compared to the conventional hopper (and the effect is greater when the silent plate is thicker than the wall). In addition, it is generally known that human hearing is easy to hear (has good sensitivity) sounds in the frequency band around 3000 Hz, but it was confirmed that the frequency band of the hopper according to this embodiment changes from a close band (around 8000 to 9000 Hz) to a distant band (around 12000 to 14000 Hz) relative to the band (around 3000 Hz), that is, the sound changes to a sound that is difficult to hear (or is not harsh to the ears) compared to the conventional hopper. Therefore, it is considered that the hopper according to this embodiment effectively suppresses reverberation due to these synergistic effects.

[0040] As described above, the hopper according to the present invention can simultaneously achieve weight reduction and suppression of reverberation caused by scattering and collision of the treated material (resin product). In particular, by applying the hopper to a granulator in which reverberation is more likely to occur due to structural factors, reverberation can be effectively suppressed.

[0041] The present invention is not limited to the above-described embodiment. For example, the present invention is not limited to a granulator as a processing device, but may be applied to a crusher. [Explanation of symbols]

[0042] 1 Graining machine 12 Rotating crushing blade 20 Hopper 21 Wall 22 Opening (inlet) 24 Silent Plate 40 Main unit 60 Movable grain cutting blade 70 Fixed grain cutting blade

Claims

1. A hopper for feeding a resin formed material produced during resin molding into a processing device, A wall portion surrounding the outer periphery is formed using a plate material made of a metal material, and an opening is provided at the top to serve as an inlet for the resin molding, At least the left and right walls of the wall portions are provided with sound-reducing plates for suppressing reverberation generated when the resin-formed product scatters and hits a plate surface during processing. Hopper features.

2. The silent plate is made of a metal plate material and is formed to have a thickness greater than that of the wall portion to which it is to be attached.

2. The hopper according to claim 1,

3. The silent plate is attached so as to include a position in the vicinity of the opening.

3. The hopper according to claim 2,

4. The upper wall portion and the rear wall portion of the wall portion are connected via a chamfered inclined wall portion, The silent plate is not attached to the upper wall portion, the rear wall portion, and the inclined wall portion.

2. The hopper according to claim 1,

5. A granulator as the processing device, in which the hopper according to any one of claims 1 to 4 is attached to an upper part of a main body, The main body includes a rotary crushing blade for roughly crushing the resin-formed material fed through the hopper, a fixed grain cutting blade having a plurality of small shear blades arranged side by side below the rotary crushing blade, and a movable grain cutting blade having a plurality of shear blades arranged side by side by reciprocating drive to mesh with the fixed grain cutting blade and cut the resin-formed material roughly crushed by the rotary crushing blade. A granulator characterized by:

6. The lower end of the hopper and the upper end of the rotary crushing blade are disposed so as to be at a distance within +10 mm to -10 mm.

6. The granulator according to claim 5,

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