JPH0679799B2 - Rotary powder compression molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a rotary powder compression molding machine for compressing a powder material in a die of a rotary disk through an upper punch and a lower punch to mold tablets and the like. In particular, the present invention relates to an improvement in the structure for detecting the squeak of the upper punch.

[Prior Art] As shown in FIG. 6, the upper punch 1 of the rotary powder compression molding machine is
The rotary table 2 is supported by the upper punch slide hole 3 so as to be able to move up and down, and the vertical movement is made by following the cam surface 5 of the upper punch guide track 4 arranged on the upper side of the rotary disk 2. The upper punch guide track 4 was fixed to the fixed upper frame 6.

Further, in order to prevent galling, wear, and seizure of the cam surface 5 due to the crease of the upper punch 1, the crease detecting means 7 shown in FIG. 6 is conventionally arranged along the descending portion 5a of the cam surface 5. ing. The detection means 7 supports a detection plate 11 along the descending portion 5a via a leaf spring 10 on a base 9 bolted to the upper frame 6 via a spacer 8 and near the back surface of the detection plate 11. Detector switch located at 12
Is fixed to the upper frame 6 and formed.

According to the squeak detection means 7, the detection plate 11 is normally separated from the detection switch 12. When the upper pestle 1 is creaked due to the increase of the sliding resistance in the upper pestle sliding hole 3 and the smooth lowering due to its own weight cannot be performed, the head of the upper pestle 1 detects the detection plate.
Upon hitting 11, the leaf spring 10 is displaced as a fulcrum as shown by the chain double-dashed line in FIG. Therefore, the detection switch 12 is pressed by the detection plate 11. In this way, the snarl of the upper punch 1 can be detected, and the detection signal is used for ensuring safety such as machine stop.

[Problems to be Solved by the Invention] As described above, in conventional squeak detection, it is only possible to deal with squeak when the upper punch is lowered. By the way, the creaking of the upper pestle 1 is not only caused by the increase of the sliding resistance due to the intrusion of dust into the upper pestle sliding hole 3, but also the running out of the lubricating oil or the upper pestle sliding hole 3 due to the sliding. It is also caused by twisting due to a tilting phenomenon of the upper punch 1 due to wear of the upper punch 1. However, problems such as galling and seizure of the head of the upper punch 1 with respect to the cam surface 5 are more likely to occur in the rising portion of the upper punch 1 than in the lowering portion. However, the conventional configuration is not effective for preventing troubles in this part. Moreover, since the head of the upper punch 1 slides on the annular cam surface 5,
However, this rotation is also hindered by the various causes of squeaking described above, and as a result, troubles such as galling or seizure of the head of the upper punch 1 with respect to the cam surface 5 may occur. However, the conventional configuration is not effective as a countermeasure against this point.

An object of the present invention is to obtain a rotary powder compression molding machine capable of reliably preventing problems such as galling, seizure, and abrasion of the upper punch with respect to the upper punch guide track.

[Means for Solving the Problems] In order to achieve the above object, in the rotary powder compression molding machine according to the invention of claim 1, a large number of dies and as many upper and lower punches as the dies can be moved up and down. And a rotary disc supporting the upper and lower punches, and an annular cam surface for moving the upper punch upward and downward. The rotary disc is located between the rotary disc and an upper frame arranged above the rotary disc, and can be finely moved in the circumferential direction. Has an upper punch guide track arranged on the above and a descending slope similar to the descending part of the cam surface,
An upper punch lowering device located at the descending portion and fixed to the upper punch guide track, and an engaging portion provided on the upper punch guide track,
A stopper portion which is attached to the fixing member and is located on the side where the upper punch guide track is moved with respect to the engagement portion due to the occurrence of squeezing of the upper punch, the stopper portion facing the engagement portion, and the engagement portion and the stopper portion. An urging body sandwiched between the movable shaft, a movable shaft having one end engaged with the engaging portion and the other end loosely inserted in the through hole of the stopper, and pushed by the movable shaft. A crease detecting means that is formed with a detection element and that detects a movement in the circumferential direction of the upper punch guide orbit due to the creaking as a displacement amount above a certain degree, and based on the crease detection by the crease detecting means It is intended to prevent the trouble about the upper punch between the upper punch guide track and the upper punch.

Further, in order to achieve the same object, in the rotary powder compression molding machine according to the invention of claim 2, a rotation supporting a large number of dies and the same number of dies as the dies capable of moving up and down respectively. A disc and an annular cam surface for raising and lowering the upper punch, and is located between the rotary disc and an upper frame disposed above the rotary disc and is disposed so as to be finely movable in the circumferential direction. It is provided on the upper punch guiding track and the upper punch lowering device which has the same descending slope as that of the lower part of the cam surface and is fixed to the upper punch guiding track at the descending part. And an engaging portion, a stopper portion which is attached to the fixing member, is disposed on the side where the upper punch guide track is moved based on the occurrence of squeezing of the upper punch with respect to the engaging portion, and the engaging portion is in pressure contact. It is formed with a pressure-electricity converter provided on the stopper portion having a protrusion. A crease detecting means for detecting, as a pressure, a circumferential movement of the upper pestle guide orbit due to the crease as a pressure, and the upper pestle guide trajectory and the upper pestle based on the crease detection by the crease detecting means. It is intended to prevent the trouble about the above-mentioned upper punch between and.

[Operation] In a rotary powder compression molding machine, if dust is introduced into the upper punch sliding hole of the rotary disc or the upper punch is twisted due to tilting of the upper punch, etc. The head of the punch strongly pushes the cam surface of the upper punch guide track in the rotating direction of the turntable.
Similarly, in the descending part of the cam surface that lowers the upper punch,
The head of the upper punch hits the upper punch lowering device fixed to the upper punch guiding track, and this head strongly pushes the upper punch guiding track in the rotating direction of the turntable via the upper punch lowering device. Also, if the rotation of the upper punch is hindered by the twisting of the upper punch, the head of the upper punch comes into sliding contact with the cam surface without rotating, and the frictional resistance between them increases. As a result, the force for turning the upper punch guide path increases. By the way, since the upper punch guide track can make slight movements in the circumferential direction, when the force acting on the upper punch guide track due to the squeezing of the upper punch exceeds a predetermined value as described above, the upper punch guide track moves around its circumference. Rotate a little in the direction. Such fine movements in the circumferential direction of the upper punch guide track are detected by the squeak detecting means.

That is, in claim 1, when the force for turning the upper punch guide track due to the bending of the upper punch becomes larger than the biasing force of the biasing body, the movable shaft is pushed by the engaging portion against the biasing force. Since it is moved, the detecting element is pushed via this movable shaft, and thereby the change in the position of the upper punch guide track is transmitted to the detecting element. Therefore, when the position change becomes equal to or more than a certain value, the movement, that is, a fine movement in the circumferential direction of the upper punch guiding path due to the squeezing to a certain value or more is detected by the detection element.

Further, in the present invention, the force for turning the upper punch guide track by the bending of the upper punch is applied to the pressure receiving portion of the pressure-electricity converter through the engaging portion. The circumferential movement of the guide track is detected as pressure by the pressure-electricity converter. Therefore, when the upper punch guide track is finely moved in the circumferential direction above a certain level due to the squeak, an electric value corresponding to the pressure applied to the pressure receiving portion at that time is detected by the pressure-electric converter.

As described above, in the first and second aspects, the squeak of the upper punch can be detected. Therefore, in order to prevent troubles about the upper punch between the upper punch guide track and the upper punch, this molding machine performs trouble prevention processing such as stopping the operation of the machine, based on the detection of the squeak. It can be carried out.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

Reference numeral 21 in FIG. 3 denotes an upper frame arranged and fixed above a fixed lower frame (not shown) of the main body frame, and the four corners of these two frames are connected to each other through columns (not shown). Support cylinder 22 on the upper surface of the lower frame
Is attached, and various lower punch driving members that are located around the cylindrical body 22 and that move the lower punch 23 up and down are provided. Incidentally, in FIG. 3, only the lower punch lowering track 24 is shown as the lower punch driving member.

The support cylinder 22 rotatably supports the drive shaft 26 via a pair of upper and lower bearings (only the upper bearing is shown) 25 provided inside the support cylinder 22 so as to be spaced apart from each other. The lower end of the drive shaft 26 is connected to the output end of a rotary drive device (not shown) built in the lower frame, and the upper end of the drive shaft 26 rotates on the protrusion 21a of the upper frame 21 via the bearing 27. It is supported freely.

A turntable 31 that is rotated together with the drive shaft 26 is supported on an upper portion of the drive shaft 26 protruding from the support cylinder 22. The turntable 31 is formed by connecting an upper rotary body 31a and a lower rotary body 31b with a large number (only one is shown) of bolts 32. The inner peripheral portion of the upper rotating body 31a has a collar portion 26a of the drive shaft 26.
Is mounted via a ring-shaped seat 33, and the turntable 31 is passed through an upper rotor 31a and a plurality of bolts 34 (only one is shown) screwed into the collar portion 26a. Drive shaft
It is connected to 26. In FIG. 3, reference numeral 35 is a ring plate having an upright portion on the inner circumference, and 36 is an oil seal.

The upper rotary body 31a is provided with an upper punch guide collar 38 for guiding the vertical movement of the upper punch 37. On the lower rotating body 31b, the lower punch 2
A lower punch guide collar 39 for guiding the lifting and lowering of 3 is provided, and a die mounting collar 40 is provided between the flange 39 and the guide collar 38.

On the upper punch guide collar 38, a large number of upper punch slide holes 41 (only one is shown in FIG. 3) are located on the same circle drawn with the drive shaft 26 as the center, and are arranged at predetermined intervals. It is provided corresponding to the number of punches 37. An upper punch 37 is vertically pierced through each of the sliding holes 41.

The lower punch guide collar 39 also has a large number of lower punch slide holes 42 (only one is shown in FIG. 3) located on the same circle drawn around the drive shaft 26 at predetermined intervals. It is provided corresponding to the number of 23. The lower pestle 23 is vertically pierced through each of the lower pestle sliding holes 42.

The same number of dies 43 as the number of punches are attached to the mortar attachment collar 40 at predetermined intervals. The punch tip of the lower punch 23 is inserted into the die 43 to form the bottom of the die hole, and the upper punch
The punch tip of 37 is inserted into and removed from the die hole from above,
The powder material is compression-molded in the mortar 43 by the up-and-down movement of 7,23.

An upper punch guide track 45 for moving the upper punch 37 up and down is arranged between the upper frame 21 and the turntable 31. This orbit 45
Is formed of a ring-shaped track base 46 in plan view and a ring-shaped track body 48 in plan view connected to a peripheral portion of the base 46 with a large number of bolts (only one shown) 47.

The track base 46 is supported by the drive shaft 26 via a bearing 49 so as to be rotatable in the circumferential direction. An annular cam surface 51 with which the head of the upper punch 37 contacts is formed on the track body 48. The cam surface 51 has a rising portion 51a and a lowering portion 51b as shown in FIGS.
And an upper horizontal portion 51c that connects the upper ends of these two portions 51a and 51b.
And a lower horizontal portion 51d that connects the lower ends of the both portions 51a and 51b to each other. In FIG. 2, the angle range of θ _{1 corresponds to} the rising portion 51a, θ _{2 corresponds} to the descending portion 51b, θ _{3 corresponds} to the upper horizontal portion 51c, and θ ₄ corresponds to the lower horizontal portion 51d.

On the upper surface of the track base 46, an upward engaging portion 50 located in the angle range of θ ₃ is projected by welding, and an upper punch lowering device 52 is located substantially in the angle range of θ _2. It is bolted. The lower surface 52a of the lowering device 52 has a descending slope similar to that of the descending portion 51b as shown in FIG. Then, the upper punch lowering device 52 moves the lower side of the lower surface 52a to the upper punch 3
It is provided along the movement locus L of the upper punch 37 so that the head of 7 passes (see FIG. 2).

The protrusion 21a of the upper frame 21 is provided with a squeak detecting means 55 shown in FIGS. 1 and 2. This means 55 includes a stopper portion 56 that is opposed to the engaging portion 50 and protrudes from the side surface of the protrusion 21a, a movable shaft 57 that is provided by loosely inserting a through hole 56a of the stopper portion 56, and a biasing force. Coil spring as body 58
And a limit switch 59 as a detection element.

The stopper portion 56 is located on the side where the upper punch guide track 45 is moved with respect to the engaging portion 50 when the upper punch 37 is snarled, and is provided so as to face the engaging portion 50. The movable shaft 57 has a stepped structure, the small-diameter tip part of which is loosely inserted into the through hole 56a of the engaging part 50, and the step part is on the surface of the engaging part 50 facing the stopper part 56. Engaged. A retaining member 60 is bolted to this tip portion. A coil spring 58 around which the movable shaft 57 is wound is sandwiched between the engaging portion 50 and the stopper portion 56. The spring 58 urges the engaging portion 50 in the direction of arrow A in FIG. 1, and the force thereof prevents the upper punch guide track 45 from unintentionally rotating.

As described above, the squeak detecting means 55 has a function of holding the upper punch guide track 45 in a stationary state, and also has a coil spring 58.
A slight rotation in the circumferential direction of the upper punch guide track 45 within the bending range of
That is, it is configured to allow a slight movement. The arrow B in FIGS. 1 and 2 indicates the direction of rotation of the turntable 31.

The limit switch 59 is fixed to the side surface of the protrusion 21a with its actuator portion 59a in contact with the head 57a of the movable shaft 57. This switch 59 has a normally open contact structure, and by closing this contact, the operation of this rotary tablet machine is prevented in order to prevent problems such as galling, seizure, and abrasion of the upper punch. The signal to stop is obtained.

The upper frame 21 is located within the angle range of θ ₄ and has an upper punch.
An upper roll (see FIGS. 1 and 2) 61 for applying a pressing force to 37 is attached. Further, a lower roll (not shown) which is paired with the upper roll 61 and which applies a pressing force to the lower punch 23 is also attached.

In the normal molding state of this rotary tableting machine, the upper punch guide track is generated by the spring force of the coil spring 58 of the squeak detecting means 55.
Since 45 is held stationary, the upper punch 37 moves its head to the cam surface of the upper punch guide track 45 during one rotation of the turntable 31, that is, during one forming cycle indicated by S in FIG. It is moved up and down by rolling contact with 51 and passing through each part 51a to 51d of the cam surface 51. At the same time, the lower punch 23 is also moved up and down in time with the vertical movement of the upper punch 37 by the lower punch driving member such as the lower punch lowering track 24 during the one molding cycle S.
Therefore, the powder material is compression-molded in the die 43 by the vertical movement of the upper and lower punches 37, 23.

By the way, when the upper punch 37 begins to crease due to the inclination of the upper punch 37 due to the intrusion of dust into the upper punch sliding hole 41 or the abrasion, or the oil running out, etc. Problems such as galling, seizure, and abrasion of the upper punch 37 can be reliably prevented.

That is, when the upper punch 37, which is moved together with the turntable 31, ascends, the upper punch 37 fails to rise due to the squeezing of the upper punch 37, and the upper punch 37 moves up the cam surface 51 of the stationary upper punch guide track 45. The part 51a is not smoothly driven and the upper punch 3
The head of 7 has a force F greater than the biasing force of the coil spring 58.
_{At 1} (see FIG. 1), the upper punch guide track 45 is strongly pushed in the rotating direction of the turntable 31.

The action of this force F ₁ causes the engaging portion 50 to approach the stopper portion 56 while compressing the coil spring 58, and the upper punch guide track 45 is finely moved in the circumferential direction thereof.
Is pushed to the limit switch 59 side. The movable shaft 57 includes a through hole 50a of the engaging portion 50 and a through hole 56a of the stopper portion 56.
Since they are penetrated with play, the movable shaft 57 can move together with the upper punch guide track 57 due to the play. Therefore, since the limit switch 59 is pushed through the displacement of the movable shaft 57, the switch 59 is closed and the operation of the machine is stopped.

When the upper punch 37 descends, the upper punch 37 keeps substantially the same height due to a poor lowering due to the squeezing of the upper punch 37, so that its head is separated from the descending portion 51b of the cam surface 51 and the upper punch 37 is lowered. Guide track 45
The lower face 52a of the upper punch lowering device 52 fixed to the upper punch lowering device 52 is hit, and a force F ₂ larger than the urging force of the coil spring 58 is exerted via the lowering device 52.
(See FIG. 1), the upper punch guide track 45 is strongly pushed along the rotation direction of the turntable 31. Due to the action of this force F ₂ , the squeak detection means 55 in the same manner as in the case of the above-mentioned rise failure
Detects that the upper punch guide path 45 has moved slightly in the circumferential direction. Therefore, the operation of the machine is stopped.

Furthermore, not only when the upper punch 37 is moving up and down,
Even during other horizontal movements, that is, when moving in the range of the angles θ ₃ and θ ₄ , due to the squeezing of the upper punch 37,
When the rotation of the upper punch 37 is blocked, the cam surface 51
On the other hand, the head of the upper punch 37 slides, and the frictional resistance between them increases. Therefore, the force for rotating the upper punch guide track 45 increases, and the force causes the upper punch guide track 45 in the stationary state to slightly move in the circumferential direction against the biasing force of the coil spring 58. The snarl is detected by the means 55 and the operation of the machine is stopped.

That is, as described above, the cam surface 51 of the upper punch guide track 45 is
Since it is possible to detect the squeezing of the upper punch 37 in all the areas of the above, it is possible to surely prevent troubles such as galling, seizure, and abrasion of the upper punch 37 with respect to the upper punch guide track 45.

The present invention is not limited to the above embodiment.

For example, as the detection element, a potentiometer 64 such as a displacement converter or a differential transformer connected to the movable shaft 57 as shown in FIG. 4 may be used instead of the limit switch, or not shown. May use a proximity switch.

As shown in FIG. 6, the squeaking detection means 55 includes a stopper portion 56, a pressure-electric converter 65 such as a load cell or a piezoelectric element attached to the stopper portion 56, and the converter portion 65 that serves as the stopper portion 56.
It may be formed by another stopper portion 66 protrudingly provided on the protrusion 21a between and. Incidentally, g in FIG. 6 indicates a gap. In this case, the engaging portion 50 provided on the upper punch guide track 45 is in contact with the pressure receiving projection 65a of the pressure-electricity converter 65.

Therefore, in this example, a force for rotating the upper punch guide track 45 in the circumferential direction based on the bending of the upper punch is applied to the pressure-electricity converter 65 via the engaging portion 50. Therefore, the fine movement of the upper punch guide path 45 is detected as the electric value of the pressure converted by the pressure-electric converter 65, not the displacement amount.

Further, in the above-mentioned one embodiment, the upper punch guide track 45 is rotatably supported with respect to the drive shaft 26 so that it can be finely moved, but the present invention is not limited to this, and the upper punch guide track 45 is rotatably attached to the upper frame 21 or the turntable 31. It doesn't matter.

Further, the fixing member to which the squeak detecting means is attached is not limited to the upper frame, but may be a member connected to the pillar of the main body frame.

[Advantages of the Invention] In the rotary powder compression molding machine of the present invention described above, the force of the upper punch trying to rotate the upper punch guide orbit in the circumferential direction due to the squeezing of the upper punch is moved in the circumferential direction of this orbit. Is detected as the displacement amount or pressure to detect the creases of the upper punch, so that even if the creases of the upper punch are generated at any position, it is possible to reliably detect the creases. Therefore, problems such as galling, seizure, and abrasion of the upper punch with respect to the upper punch guide track can be reliably prevented.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 is an expanded view of FIG. 2, and FIG. 2 is an upper punch guide track and an upper punch disposed around it. FIG. 3 is a plan view showing the positional relationship of the squeaky detecting parts and the like, and FIG. 3 is a longitudinal sectional view showing a part of the rotary tableting machine. FIG. 4 and FIG. 5 are diagrams showing the configurations of different modified examples of the squeak detecting means shown in FIG. FIG. 6 is an expanded view showing the configuration around the conventional squeak detecting means. 21 …… Upper frame (fixing member), 21 …… Lower punch, 31 ……
Rotating disk, 37 …… Upper punch, 43 …… Mortar, 45 …… Upper punch guide track,
50 …… engagement part, 51 …… cam surface, 51b …… falling part, 52 ……
Upper punch lowering device, 55 …… Screw detection means, 56 …… Stopper part,
50a, 56a ... through hole, 57 ... movable shaft, 58 ... coil spring (biasing body), 59 ... limit switch (detection element), 64
...... Potentiometer (detection element), 65 ...... Pressure-electric converter, 65a ...... Pressure receiving part, 66 ...... Other stopper parts.

Claims (2)

[Claims] 1. A rotary disk supporting a plurality of dies and an upper pestle and a lower pestle of the same number as these dies, respectively, and an annular cam surface for moving the upper pestle up and down. It has an upper punch guide track, which is located between the upper frame arranged above the rotating disk and is capable of fine movement in the circumferential direction, and a descending slope similar to that of the descending part of the cam surface. Upper punch lowering device which is located on the upper punch guide track and is fixed to the upper punch guide track, an engaging portion provided on the upper punch guide track, and a bending of the upper punch with respect to the engaging part attached to the fixing member. A stopper portion located on the side where the upper punch guide track is moved on the basis of the occurrence and facing the engaging portion, a biasing body sandwiched between the engaging portion and the stopper portion, and one end portion of the engaging portion. A movable shaft that is engaged with the mating portion and has the other end loosely inserted in the through hole of the stopper portion, and And a crease detecting means for detecting a movement in the circumferential direction of the upper pestle guiding track which is more than a certain amount due to the crease as a displacement amount, and the crease detecting means A rotary powder compression molding machine, characterized in that troubles about the upper punch between the upper punch guide track and the upper punch are prevented based on the detection of squeak. 2. A rotary disk having a plurality of dies and supporting upper and lower punches of the same number as the dies, respectively, and an annular cam surface for moving the upper punch up and down. It has an upper punch guide track, which is located between the upper frame arranged above the rotating disk and is capable of fine movement in the circumferential direction, and a descending slope similar to that of the descending part of the cam surface. Upper punch lowering device which is located on the upper punch guide track and is fixed to the upper punch guide track, an engaging portion provided on the upper punch guide track, and a bending of the upper punch with respect to the engaging part attached to the fixing member. Formed by a pressure-electricity converter attached to the stopper part having a stopper part arranged on the side where the upper punch guide track is moved on the basis of occurrence and a pressure receiving projection part with which the engaging part abuts The circumferential movement of the upper punch guide orbit due to the squeezing above a certain level is used as pressure. A squeak detecting means for detecting is provided, and troubles about the upper punch between the upper pestle guide track and the upper pestle are prevented based on the squeak detection by the squeaking detection means. The rotary powder compression molding machine.