JP3699689B2 - Rotary powder compression molding machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotary powder compression molding machine such as a rotary tableting machine that compresses tablets.
[0002]
[Prior art]
A powder feeder is disposed above the mortar mounting portion of the rotary disk included in the rotary powder compression molding machine. The powder feeder has a soft powder seal such as felt on its lower end surface. By making this powder seal contact the upper surface of the mortar mounting portion, powder leakage is suppressed. However, even if the powder seal is soft, it cannot prevent the upper surface of the mortar mounting portion from being worn.
[0003]
In order to cope with this, the hard disk is hardened, a hard chrome plating layer or a super steel alloy layer is provided on the upper surface of the mortar mounting portion, or the cover plate is exchangeably applied. Yes.
[0004]
Since the heat capacity of the rotating disk is extremely large, special equipment is required for quenching that requires rapid cooling. Therefore, quenching of the rotating disk is extremely expensive and generally difficult.
[0005]
Since the surface area of the mortar mounting portion of the rotating disk is large and there are many mortar mounting holes, it is a relatively difficult technique to form a uniform hard chrome plating layer on the upper surface of the mortar mounting portion. For this reason, it is difficult to eliminate pinholes or the like in the plating layer, and plating defects are likely to occur. When there is a plating defect, peeling of the hard chrome plating layer is induced from the defective part, rusting at the defective part, and powder remaining on the defective part. Under such circumstances, the hard chrome plating layer is generally in a state where durability exceeding 5 years cannot be obtained even at the longest.
[0006]
The super steel alloy layer is provided by spraying super steel metal, which is very expensive compared to the plating process. In addition, since the super steel alloy layer is very hard, it is difficult to polish the surface of the super steel alloy layer, which increases costs. For these reasons, it is difficult to adopt a super steel alloy layer and it is not common.
[0007]
When a cover plate is used, this cover plate is detachably attached to the upper surface of the mortar attachment portion in the following two configurations. First, the cover plate is attached to the upper surface of the die attachment portion from above using a plurality of bolts that are inserted through the cover plate from above and screwed into the die attachment portion. Second, a plurality of non-penetrating screw holes are provided in the upper surface of the cover plate, and the tip of the bolt that passes through the mortar mounting portion from below to above is screwed into these screw holes, thereby fixing the cover plate to the cover plate. It is attached to the upper surface of the die attachment part from below.
[0008]
In any configuration, it takes time and effort to attach and detach a large number of bolts when attaching and detaching the cover plate. Moreover, in the former configuration, since it is necessary to carry out a counterbore process so that the bolt head does not protrude from the cover plate, there is a problem that powder tends to remain in the portion where the bolt passes, and a thick cover plate is required. And Even in the latter configuration, in order to obtain a required mounting strength, the screw hole needs to have a certain depth, and in this case as well, a thick cover plate is required. Therefore, in general, a cover plate having a thickness of about 15 mm or more must be used. The thicker the cover plate is, the thinner the mortar mounting portion must be.
[0009]
By the way, many mortars arranged in the mortar mounting portion are fixed by mortar fixing bolts screwed from the outer periphery of the mortar mounting portion. For this reason, when the cover plate is to be attached to a small rotary powder compression molding machine or the like having a small thickness of the mortar attachment portion itself, the mortar attachment portion becomes thinner. Therefore, since the strength that receives the reaction force of tightening the mortar fixing bolt at the mortar mounting portion is reduced, it is difficult to apply the cover plate to a small rotary powder compression molding machine or the like.
[0010]
[Problems to be solved by the invention]
The problem to be solved by the present invention is to obtain a rotary powder compression molding machine that can be easily attached to and detached from a cover for preventing wear of a die mounting portion of a rotating disk and can be applied to various models.
[0011]
[Means for Solving the Problems]
The present invention provides a plurality of mortar fitting holes for attaching a large number of mortars to the mortar mounting portion using mortar fixing bolts screwed from the outer peripheral surface of the mortar mounting portion of the rotating disk, and fitting the upper end portion of the mortar. Is a rotary powder compression molding machine in which the cover is detachably attached to the upper surface of the mortar mounting portion.
[0012]
And in order to solve the said subject, the said cover is attached and hold | maintained at the said die mounting part by magnetic force, It is characterized by the above-mentioned.
[0013]
The rotary powder compression molding machine of the present invention can suitably compress, for example, tablets, and can also compress green compacts other than tablets. Furthermore, in the present invention, the plurality of covers only need to have at least a flat plate-like portion, and each cover may have one mortar fitting hole, but the number of covers used as a plurality should be reduced. Is desirable. Further, the plurality of covers may be divided into the same size in order to share parts, and it is desirable that each cover has a bilaterally symmetric shape so that both front and back surfaces can be used.
[0014]
Further, in the present invention, a permanent magnet or an electromagnet can be used as the magnetic attraction means for attaching and holding the cover to the mortar attachment portion with a magnetic force. As a preferred embodiment of the present invention, the cover may be made of a metal magnetic material, and a plurality of permanent magnets may be embedded in an iron, cast, or stainless steel mortar mounting portion. In this case, it is preferable that a part of the magnetic attraction means be installed so as to be disposed between the ends of the adjacent covers because the lift of the ends of the covers can be effectively prevented. Furthermore, when the mortar mounting part is made of iron or cast metal, a permanent magnet can be mounted on the back side of the cover. Moreover, when using an electromagnet, this can be implemented by being embedded in the mortar mounting portion.
[0015]
Further, in the present invention, it is not obstructed to perform means for improving the durability of the cover, for example, modification or deposition of a wear resistant layer as necessary. Here, the modification refers to, for example, an improvement in hardness by quenching, and the wear-resistant layer refers to, for example, a hard chrome plating layer provided on at least one surface of the cover.
[0016]
In the present invention, each cover covering the upper surface of the mortar mounting portion is supported by the mortar mounting portion on the back surface, and is also displaced in the circumferential direction of the mortar mounting portion by fitting the mortar fitting hole with the mortar. Not only is it supported so that it does not move, but it is held by the mortar mounting portion so that it does not move upward by magnetic force. Therefore, each cover can be removed from the mortar mounting portion by applying an upward external force that is superior to the magnetic force to the cover or by eliminating the magnetic force. On the contrary, each cover can be attached to the upper surface of the mortar mounting portion by attaching a new cover or an inverted cover to the mortar mounting portion by magnetic force while fitting the mortar at a predetermined position. Therefore, it is not necessary to tighten and remove a large number of bolts for attaching and detaching the cover.
[0017]
Since each cover is not provided with a recess for accommodating the head portion of the bolt or a screw hole for screwing the bolt, the thickness of each cover can be reduced as necessary. Therefore, the thickness of the mortar mounting portion can be stopped to such an extent that the support strength of the mortar fixing bolt is not impaired. Therefore, it is suitable also when it implements as a small rotary powder compression molding machine which attached the cover on the die attachment part.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
[0019]
1 shows a rotary table of a rotary powder compression molding machine, for example, a rotary tableting machine A, denoted by reference numeral 1 in FIG. The turntable 1 includes, for example, an annular turntable upper portion 1a and an annular turntable lower portion 1b connected to the turntable 1 via a plurality of bolts (not shown). The turntable upper part 1a and the turntable lower part 1b are made of casting, iron, stainless steel, or the like. In addition, when the turntable 1 is small, etc., it is not divided into upper and lower parts as described above, but can be formed integrally. The rotating disk 1 is connected to a rotating shaft 2 (see FIG. 2) that is concentrically disposed at the center thereof. The rotating disk 1 is rotated integrally with the rotating shaft 2 by the driving force applied to the rotating shaft 2.
[0020]
The upper part 1a of the turntable is integrally provided with an upper hook attaching part 3 projecting outward. The upper collar mounting portion 3 is provided with a number of upper collar guide holes 4 (only one is shown) at equal intervals in the circumferential direction. The upper collar guide hole 4 made of a round hole is opened vertically with its upper and lower ends open.
[0021]
A mortar mounting portion 5 that projects outward is integrally provided on the upper portion of the rotating plate lower portion 1b, and a lower punch mounting portion 6 that projects outward is integrally provided on the lower portion of the rotating plate lower portion 1b. A number of mortars 7 are mounted on the mortar mounting portion 5 so as to be positioned on the axial extension of the upper eyelid guide hole 4. These mortars 7 are arranged at equal intervals on concentric circles drawn with the same radius around the axis of the rotary shaft 2 as shown in FIG.
[0022]
These mortars 7 are attached by mortar fixing bolts 8 screwed from the outer peripheral surface of the mortar attachment portion 5 as shown in FIGS. The mortar fixing bolt 8 is fixed so that the mortar 7 does not come out upward by pushing an annular groove formed on the outer peripheral surface of the mortar 7 at its tip 8a. Each mortar bolt 8 can be removed. The height of each die 7 is defined by an annular step portion 5b in the die attachment hole 5a of the die attachment portion 5 shown in FIG. Thereby, the upper end portion of each die 7 attached to the die attachment portion 5 is projected from the upper surface 5 c of the die attachment portion 5.
[0023]
A number of lower eyelid guide holes 9 (only one is shown) are formed in the lower eyelid attachment portion 6 so as to be positioned on the axial extension of the upper eyelid guide hole 4. Both ends of the lower rod guide hole 9 made of a round hole are opened to the upper and lower ends of the lower rod mounting portion 6. A number of lower rods 10 (only one is shown) are attached to the lower rod mounting portion 6 through the lower rod guide holes 9 slidably.
[0024]
The tip portion 10a of each lower punch 10 is slidably inserted and held in the mortar hole 7a of the corresponding mortar 7, and forms the bottom of the mortar hole 7a. A lower head 10b that forms the lower end of each lower rod 10 contacts and separates various lower cams 11 and lower pressure rollers such as a lower pressure roller (not shown) as the turntable 1 rotates. Go up and down.
[0025]
By raising and lowering the lower punch 10, at the powder supply position, the raw material powder in the powder feeder 25 described later is sucked into the mortar hole 7a and the surplus powder is discharged into the powder feeder 25 after that. Weighing is performed. Thereafter, the height position of the weighed raw material powder in the mortar 7a is lowered. At the next compression position (including at least the latter of the pre-compression and the main compression), the raw material powder in the mortar 7a is pushed up in order to compress the raw material powder together with the upper punch 14 described later. Further, at the subsequent take-out position, a product (a green compact such as a tablet) in the die 7 compression-molded so as to be suitable for taking out the product with a scraper (not shown) is pushed upward from the die hole 7a.
[0026]
Reference numeral 12 in FIG. 1 denotes an annular upper cam fixed to a fixed upper frame 13 located above the rotating disk 1. At the center of the upper cam 12, the upper end portion of the rotary shaft 2 is rotatably supported via a bearing (not shown). The upper cam 12 has a cam portion 12a for raising and lowering an upper collar, which will be described later, on the outer periphery thereof. An escape portion is provided in a part of the cam portion 12a, and an upper pressure roller (not shown) supported by the upper frame 13 is disposed in correspondence with the lower pressure roller.
[0027]
The upper cam 12 and the upper pressure roller function as an upper arm driving body that moves up and down the same number of upper shafts 14 (only one is shown) as the die 7. Each upper collar 14 penetrates the upper collar guide hole 4 of the upper collar mounting portion 3 slidably. Each upper punch 14 is moved up and down as the turntable 1 rotates, and the tip portion 14 a is inserted into and removed from the mortar hole 7 a of the mortar 7 facing from above. As the tip portion 14a is inserted into and removed from the mortar hole 7a, the powder in the mortar hole 7a can be compression-molded in cooperation with the lower punch 9 and the mortar 7.
[0028]
A plurality of, for example, four covers 21 are detachably attached to the upper surface 5 c of the mortar mounting portion 5. Each cover 21 is made of a flat plate having a symmetrical arc shape as a preferred example, and all of them have the same size. Each cover 21 is combined in a ring shape on the upper surface 5c of the mortar mounting portion 5 in a state where the one end portion 21a and the other end portion 21b of the cover adjacent thereto are in contact with each other.
[0029]
Next, means for attaching and holding each cover 21 to the upper surface 5c of the mortar mounting portion 5 by magnetic force will be described. Each of the covers 21 is made of a metal magnetic material, such as a steel plate, preferably a gauge steel plate that is easily hardened and thus has excellent bending strength and wear resistance. Although not shown, hard chrome plating layers are provided on the front and back surfaces of these covers 21. The quenching and the hard chrome plating layer are means for further improving the durability of each cover 21, but at least one of them may be omitted. The thickness of each cover 21 is the same as the protruding dimension of the mortar 7 from the upper surface 5c, and is preferably set to 1 mm to 3 mm so as not to substantially impair the mounting strength of the mortar 7 by the mortar fixing bolt 8. Good. Each cover 21 has a plurality of mortar fitting holes 22 as shown in FIGS.
[0030]
On the other hand, a large number of permanent magnets 23 are embedded in the mortar mounting portion 5 as magnetic attraction means. As the permanent magnet 23, an alnico magnet, a ferrite magnet, a rare earth magnet, or a composite magnet obtained by mixing powder particles of these magnets with plastic or rubber and combining them can be used.
[0031]
The upper surfaces of these magnets 23 are provided so as to be exposed on the upper surface 5c so as to be flush with the upper surface 5c of the mortar mounting portion 5. Instead of this, the upper surface of the permanent magnet 23 may be exposed in a state where it is slightly lower than the upper surface 5 c of the mortar mounting portion 5. Each permanent magnet 23 is arranged on the inner peripheral side and the outer peripheral side with the die 7 as a boundary. Further, each permanent magnet 23 is arranged on a radial line centering on the axis of the rotating shaft 2 and at a position that bisects the adjacent dies 7.
[0032]
Each cover 21 has its mortar fitting holes 22 individually fitted to the upper ends of the mortars 7 and is overlapped with the upper surface 5 c of the mortar mounting portion 5, so that the magnetic force of each permanent magnet 23 causes the upper surface to move. It is sucked and held in close contact with 5c. In this attached state, as shown in FIG. 1 (B), the upper surface of the die 7 and the upper surface of each cover 21 are flush with each other, and the outer peripheral portion of each cover 21 is the outer periphery of the die attaching portion 5. It protrudes slightly outside the end. This projecting edge is used as a portion for applying an external force to each cover 21 when it is removed.
[0033]
Furthermore, in the same attachment state, the end portions 21a and 21b adjacent to each other of each cover 21 are joined by abutting their vertical end surfaces as shown in FIG. In place of such joining, as shown in FIG. 4B, the end faces of the end portions 21a and 21b can be inclined in the thickness direction, and the end portions 21a and 21b can be joined by abutting the inclined surfaces. In FIG. 4B, the arrow indicates the direction of rotation of the turntable 1. Further, as shown in FIG. 4C, chamfers can be provided on the upper and lower ends of the end portions 21a and 21b, and these end portions 21a and 21b can be abutted and joined. In the case of FIG. 4 (B) and FIG. 4 (C), the possibility that the end portions 21a and 21b may be peeled off more reliably due to the contact between the parts arranged on the mortar mounting portion 5 and the cover 21 can be more reliably eliminated. Is preferable.
[0034]
Moreover, as shown in FIGS. 4A to 4C, in the state where each cover 21 is attached to the upper surface 5 c of the mortar attaching portion 5, the end portions 21 a and 21 b joined to each other between the adjacent covers 21 extend over these. A part of the permanent magnets 23 is magnetically attracted to the upper surface 5 c of the mortar mounting portion 5. The adjacent end portions 21a and 21b are sucked in close contact with the upper surface 5c by the common permanent magnet 23 as described above, and the end portions based on the contact between the parts arranged on the mortar mounting portion 5 and the cover 21 can be used. This is preferable in that the risk of peeling off 21a and 21b can be more reliably eliminated.
[0035]
Moreover, the code | symbol 25 in FIG. 1 has shown the powder feeder which is one of the components arrange | positioned on the die mounting part 5. FIG. The powder to be compression-molded is supplied into the powder feeder 25 via a chute 26 connected to a hopper (not shown). Although not shown, a powder seal such as felt is attached to the lower end of the powder feeder 25, and this seal comes into contact with the upper surface of the cover 21 covered on the mortar attachment portion 5.
[0036]
In the tableting machine A having the above configuration, since the cover 21 is detachably attached to the upper surface 5c of the mortar mounting portion 5, in order to prevent the upper surface 5c of the mortar mounting portion 5 from being worn, It is not necessary to quench or to provide a wear-resistant layer such as hard chrome plating or super steel spraying on the upper surface 5c of the mortar mounting portion 5. And even if the removable cover 21 is greatly worn due to contact with the powder feeder 25 or the like, the wear resistance of the upper surface 5c of the mortar mounting portion 5 can be apparently reproduced by replacing the cover 21, for example. Therefore, in this reproduction, it is not necessary to repair the rotating disk 1 itself, such as polishing the upper surface 5c of the mortar mounting portion 5 and then again applying the wear resistance treatment to the upper surface 5c.
[0037]
Therefore, the cost of the tableting machine A can be reduced. Even when the cover 21 is subjected to wear resistance, the shape and the heat capacity are much smaller than those of the rotating disk 1, so that quenching can be easily and inexpensively performed, and the cost is high. It will not be.
[0038]
In the tableting machine A, the back surfaces of the covers 21 that are closely overlapped with the upper surface 5 c of the mortar mounting portion 5 are supported by the upper surface 5 c of the mortar mounting portion 5. Furthermore, the force in the circumferential direction of the mortar mounting portion 5 due to the fitting between the mortar fitting hole 22 and the upper end portion of the mortar 7, that is, the circumferential force applied from the feeder 25 and the like by relative movement with the powder feeder 25 and the like Is supported so as not to move in the same direction. In addition, it is attracted and held by the mortar mounting portion 5 so as not to move upward by the magnetic force of each permanent magnet 23.
[0039]
Each cover 21 attached in this way can be removed from the mortar attachment portion 5 by artificially applying an upward external force over the magnetic force to each cover 21 when the cover 21 is exchanged. it can. In this case, as shown in FIG. 1B, if the upper surface of the peripheral portion of the mortar mounting portion 5 is processed into an oblique shape and a wedge-shaped gap is provided between the rear surface of the cover 21, a screwdriver or the like is provided in this gap. When the removal tool is inserted and positioned on the back side of the cover 21, the removal tool is triggered, so that the cover 21 can be removed without fear of being deformed. Alternatively, a plurality of grooves extending in the radial direction of the rotating disk 1 are provided on the upper surface 5c and the outer periphery of the mortar mounting portion 5, and the outer periphery of the mortar mounting portion 5 is disposed in these grooves. By inserting the rod-shaped removal tool from the bottom of the cover 21 and positioning it on the back side of the cover 21, the cover 21 can be removed without causing the deformation of the cover 21 by causing the removal tool.
[0040]
Contrary to the removal of the cover 21, a new cover 21 or an existing cover 21 that has been turned over is placed on the mortar mounting portion 5 while being fitted to the mortar 7 at a predetermined position, whereby the mortar is attached by the magnetic force of the permanent magnet 23. Each cover 21 can be attached to the upper surface 5 c of the mortar mounting portion 5 by being attracted to the portion 5.
[0041]
As described above, each cover 21 can be easily attached and detached without the troublesome work of tightening and removing a large number of bolts, and the workability thereof is good.
[0042]
And since each cover 21 is attached to the mortar attachment part 5 without requiring a bolt, it is not necessary to provide each cover 21 with a recess for accommodating the head of the bolt or a screw hole for screwing the bolt. If necessary, the thickness of each cover 21 can be reduced to 1 mm to 3 mm, for example. Thus, when each thin cover 21 is attached on the mortar mounting part 5 of the small rotary tableting machine A, for example, the thickness of the mortar mounting part 5 is set so as not to impair the support strength of the mortar fixing bolt 8. It is possible to stop. Of course, the large rotary tableting machine A has a thick mortar mounting portion 5, so that the present invention can be carried out by attaching a cover 21 having a thickness larger than the above.
[0043]
Further, in this embodiment, since each cover 21 is symmetrical, when one surface is worn, it is attached to the upper surface 5c of the mortar mounting portion 5 with the other side turned upside down so that the other surface becomes the front. Both front and back sides of the cover 21 can be used. Therefore, it is excellent in that the life of each cover 21 can be doubled.
[0044]
In addition, in the present embodiment, each cover 21 is a simple flat plate, and no permanent magnet 23 is attached to each cover 21, so the configuration of the cover 21 is simple. Therefore, the processing of the cover 21 is easy and the cost can be reduced. In addition, both the front and back surfaces of the cover 21 can be used as described above, and it is also excellent in that the permanent magnet is not discarded when the cover 21 is replaced.
[0045]
FIG. 5 shows a second embodiment of the present invention. Since this embodiment basically has the same configuration as that of the first embodiment, the same components are denoted by the same reference numerals as those of the first embodiment, description of the configuration and operation thereof will be omitted, and different portions will be described below. Will be described.
[0046]
In the second embodiment, the end portions 21 a and 21 b of the cover 21 are formed obliquely so that the joined portions of the adjacent covers 21 intersect with the radial direction centered on the axis of the rotary shaft 2. It is configured. In accordance with this configuration, the arrangement of some permanent magnets is changed so as to extend over both the joined end portions 21a and 21b. The configuration other than the points described above is the same as that of the first embodiment including the configuration not shown in FIG.
[0047]
Also in the second embodiment, the problem of the present invention can be solved for the same reason as in the first embodiment. In addition, as described above, the end portions 21a and 21b are slanted so that the lower end surface of the powder scraper plate (which extends in the radial direction) of the powder feeder is adjacent to the adjacent end portions 21a and 21b. There is no contact with the entire joint at once. Therefore, it is preferable at the point which can eliminate more reliably the possibility that the edge parts 21a and 21b may peel off based on the contact between the powder supply and the cover 21.
[0048]
【The invention's effect】
According to the first aspect of the present invention, it is possible to easily attach and detach the cover for preventing wear of the mortar mounting portion of the rotating disk without requiring the trouble of tightening or removing a large number of bolts. Since it is possible to attach the cover onto the die mounting portion of the compression molding machine without impairing the support strength of the mortar bolt, it is possible to provide a rotary powder compression molding machine that can be applied to various models.
[0049]
According to the second aspect of the present invention, the rotary powder that the magnetic attraction means is not discarded along with the replacement of the cover, the cover structure is simple and its processing is easy, and the cost of the cover can be reduced. A compression molding machine can be provided.
[0050]
According to the invention of claim 3, since the end portions of the adjacent covers are magnetically attracted to the upper surface of the die mounting portion by the magnetic attraction means, the rotary powder compression molding machine capable of preventing the end portions of the cover from being lifted up. Can provide.
[Brief description of the drawings]
FIG. 1A is a sectional view showing a part of a rotary tableting machine according to a first embodiment of the present invention. (B) is sectional drawing which expands and shows the mortar circumference of the rotary tableting machine of FIG. 1 (A).
FIG. 2 is a cross-sectional view showing a relationship between a mortar mounting portion provided in the rotary tableting machine of FIG. 1 and a cover attached to and detached from the mortar mounting portion.
FIG. 3 is an exploded perspective view showing a relationship between a part of a mortar mounting portion included in the rotary tableting machine of FIG. 1 and a cover attached to and detached from the mortar mounting portion.
4A to 4C are different sectional views taken along line ZZ in FIG. 2. FIG.
FIG. 5 is a cross-sectional view showing a relationship between a mortar mounting portion provided in a rotary tableting machine according to a second embodiment of the present invention and a cover attached to and detached from the mortar mounting portion.
[Explanation of symbols]
A ... Tableting machine (rotary powder compression molding machine)
DESCRIPTION OF SYMBOLS 1 ... Turntable 2 ... Upper iron attaching part 5 ... Die attaching part 5c ... Upper surface 7 of the die attaching part ... Dice 8 ... Die bolt 21 ... Cover 21a, 21b ... End 22 of cover ... Die fitting hole 23 ... Permanent Magnet (magnetic attraction means)

Claims (3)

A plurality of covers having a mortar fitting hole for fitting a large number of mortars to the mortar mounting portion using a mortar fixing bolt screwed from the outer peripheral surface of the mortar mounting portion of the rotating disk, In the rotary powder compression molding machine detachably attached to the upper surface of the mortar mounting part,
The rotary powder compression molding machine, wherein the cover is attached and held to the mortar mounting portion by magnetic force. 2. The rotary powder compression molding according to claim 1, wherein the cover is made of a metal magnetic material, and a plurality of magnetic attraction means for magnetically attracting the cover is embedded in the mortar mounting portion. Machine. 3. The rotary powder compression molding machine according to claim 2, wherein a part of the magnetic attraction means is disposed between the ends of the adjacent covers.

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