Overload protection mechanism based on tablet press

Abstract

The invention discloses an overload protection mechanism based on a tablet press, and relates to the technical field of tablet presses, the overload protection mechanism comprises a rotating tower, a main pressing wheel assembly and a pre-pressing wheel assembly are arranged above the rotating tower, and a stamping die is mounted on the rotating tower; the main pressure pneumatic overload protection system comprises a main pressure air cylinder which is connected with a main pressure wheel assembly through a main pressure air cylinder piston; the pre-pressing pneumatic overload protection system comprises a pre-pressing air cylinder which is connected with a pre-pressing wheel assembly through a pre-pressing air cylinder piston; the device further comprises a pneumatic control assembly. According to the overload protection mechanism based on the tablet press, the technical problem that an existing overload protection mechanism cannot achieve real-time overload protection on parts such as a main machine, a rotating tower, a pressing wheel and a mold of the tablet press is solved, and the main pressing wheel assembly can transfer the borne overload acting force to the main air cylinder; and the main pressure cylinder rapidly drives the main pressure wheel assembly to be lifted to a certain height through the main pressure cylinder piston, so that core parts in the tablet press are effectively prevented from being damaged due to overload, and real-time protection is realized.

Description

Technical Field

[0001] The invention relates to the technical field of tablet presses, and in particular to an overload protection mechanism based on a tablet press. Background Art

[0002] The solid dosage form industry is developing rapidly, and customers have put forward higher requirements for tablet production. Tablet presses face a high-speed, high-pressure production environment. With the continuous improvement of regulations, the requirements for equipment environmental protection and energy saving are becoming higher and higher. Due to the complexity of the production environment, the equipment may occasionally be overloaded during operation due to problems such as sticking, stacking, and debris filling. The core components of the tablet press, such as the punching die, pressing wheel, and turret, may be damaged due to overload.

[0003] In the prior art, overload protection is performed by adjusting the height position of the lower pressing wheel. Since the tablet press runs at high speed during the production process, it takes a certain response time from the occurrence of overload to the completion of the motor execution. During this execution time, the pressure still maintains an overload state, so it is impossible to achieve real-time overload protection for the tablet press mainframe, turret, pressing wheel, mold and other parts. On the other hand, the flexible overload protection of the main pressing wheel by using a hydraulic cylinder with adjustable support force generally requires special customization or the use of a hydraulic cylinder with a higher technical level, which increases the cost of the tablet press. Moreover, the long-term use of the hydraulic system will inevitably lead to the aging of seals and the leakage of hydraulic oil at positions such as pipe joints. Because the tablet press has parts such as molds that are in direct contact with materials such as tablets, the hydraulic system is at risk of contaminating raw materials and finished products. Therefore, an overload protection mechanism based on a tablet press is proposed to solve the above problems. Summary of the invention

[0004] The purpose of the present invention is to provide an overload protection mechanism based on a tablet press, which solves the technical problem that overload protection is performed by adjusting the height position of the lower pressing wheel, and a response time is required from the occurrence of overload to the completion of the motor execution, and real-time overload protection cannot be achieved for parts such as the tablet press main machine, turret, pressing wheel, and mold.

[0005] To achieve the above object, the present invention provides an overload protection mechanism based on a tablet press, comprising:

[0006] frame;

[0007] A turret is rotatably arranged on the frame, a main pressing wheel assembly and a pre-pressing wheel assembly are arranged above the turret, and a stamping die is installed on the turret, and the stamping die is used for stamping powder;

[0008] The main pressure pneumatic overload protection system comprises: a main pressure cylinder rotatably connected to the frame, the main pressure cylinder being connected to the main pressure wheel assembly via a main pressure cylinder piston;

[0009] The pre-pressing pneumatic overload protection system comprises: a pre-pressing cylinder rotatably connected to the frame, the pre-pressing cylinder being connected to the pre-pressing wheel assembly via a pre-pressing cylinder piston;

[0010] The pneumatic control component includes: an air tank, which is connected to the main pressure pneumatic overload protection system through a main pressure air supply pipeline, and the air tank is connected to the pre-pressure pneumatic overload protection system through a pre-pressure air supply pipeline, and the air tank is used to store compressed air.

[0011] Preferably, the upper end of the gas storage tank is connected to a two-way joint, the first end of the two-way joint is connected to a main pressure high-precision pressure regulating valve, and the main pressure high-precision pressure regulating valve is connected to the main pressure pneumatic overload protection system through a main pressure air supply pipeline, and the second end of the two-way joint is connected to a pre-pressure high-precision pressure regulating valve, and the pre-pressure high-precision pressure regulating valve is connected to the pre-pressure pneumatic overload protection system through a pre-pressure air supply pipeline.

[0012] Preferably, a one-way valve is provided at the lower end of the gas storage tank, and the one-way valve is connected to the gas source through a system gas supply pipeline.

[0013] Preferably, both the main pressure high-precision pressure regulating valve and the pre-pressure high-precision pressure regulating valve are provided with a pressure regulating valve operation screen, and the two pressure regulating valve operation screens are used to display the pressure of the main pressure high-precision pressure regulating valve and the pre-pressure high-precision pressure regulating valve, respectively, and both the pressure regulating valve operation screens are signal-connected to the control system.

[0014] Preferably, the frame is connected to the first fixed flange, the first fixed flange is rotatably connected to the first cylinder flange, the first cylinder flange is connected to the main pressure cylinder, the main pressure cylinder is connected to the first fixed seat through the main pressure cylinder piston, the first fixed seat is connected to the main pressure strain gauge, and the pre-pressure strain gauge is used to detect the pressure exerted on the main pressure wheel assembly.

[0015] Preferably, the main pressure wheel assembly includes: a main pressure shaft, a first hydraulic tensioning sleeve is arranged on the outer peripheral side of the main pressure shaft, the first hydraulic tensioning sleeve is connected to the main pressure strain gauge, and a main pressure wheel is arranged on the outer peripheral side of the main pressure shaft, and the main pressure wheel is used to press the stamping die.

[0016] Preferably, the frame is connected to a second fixed flange, the second fixed flange is rotatably connected to a second cylinder flange, the second cylinder flange is connected to a pre-stress cylinder, the pre-stress cylinder is connected to a second fixed seat via a pre-stress cylinder piston, the second fixed seat is connected to a pre-stress strain gauge, and the pre-stress strain gauge is used to detect the pressure exerted on the pre-stress wheel assembly.

[0017] Preferably, the pre-stressing wheel assembly comprises: a pre-stressing shaft, a second hydraulic tensioning sleeve is arranged on the outer peripheral side of the pre-stressing shaft, the second hydraulic tensioning sleeve is connected to the pre-stressing strain gauge, and a pre-stressing wheel is arranged on the outer peripheral side of the pre-stressing shaft, and the pre-stressing wheel is used to press the stamping die.

[0018] Preferably, a first position detection sensor is provided on the side of the main pressure cylinder, and the first position detection sensor is used to detect the position state of the main pressure cylinder piston; a second position detection sensor is provided on the side of the pre-pressure cylinder, and the second position detection sensor is used to detect the position state of the pre-pressure cylinder piston.

[0019] Preferably, a lower main pressing wheel and a lower pre-pressing wheel are arranged below the stamping die, the lower main pressing wheel is arranged directly below the main pressing wheel, and the lower pre-pressing wheel is arranged directly below the pre-pressing wheel.

[0020] Compared with the above background technology, the present invention provides an overload protection mechanism based on a tablet press, which has the following beneficial effects:

[0021] (1) The main pressure pneumatic overload protection system of the present invention can provide overload protection for the core components such as the punching die, the pressing wheel, and the turret in the tablet press. When the force applied to the main pressing wheel assembly exceeds the set pressure, the main pressing wheel assembly will transfer the force applied to the main pressure cylinder. According to the force applied to the main pressing wheel assembly, the main pressure cylinder quickly drives the main pressing wheel assembly to a certain height through the main pressure cylinder piston, effectively avoiding damage to the core components such as the punching die, the pressing wheel, and the turret in the tablet press due to overload, and achieving real-time protection. The pre-pressure pneumatic overload protection system of the present invention also has the above beneficial effects.

[0022] (2) The main pressure pneumatic overload protection system and the pre-pressure pneumatic overload protection system of the present invention use compressed air as the medium, which can effectively avoid the risk of contaminating raw materials and finished products, and is more environmentally friendly. In addition, the tablet press itself needs compressed air to perform other actions. By supplying compressed air to the tablet press through an air storage tank, there is no need to introduce additional equipment such as an air compressor, which effectively reduces equipment costs. In addition, there are no parts that continuously consume air, which can reduce energy consumption and further save production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0024] FIG1 is a three-dimensional structural diagram of an overload protection mechanism provided by an embodiment of the present invention;

[0025] FIG2 is an axial schematic diagram of a main pressure pneumatic overload protection system provided by an embodiment of the present invention;

[0026] FIG3 is a schematic plan view of a pneumatic control assembly provided by an embodiment of the present invention;

[0027] FIG4 is a schematic diagram of the assembly of the main pressure pneumatic overload protection system and the stamping die provided in an embodiment of the present invention;

[0028] FIG5 is a partial cross-sectional schematic diagram of a main pressure pneumatic overload protection system provided by an embodiment of the present invention;

[0029] FIG6 is a cross-sectional schematic diagram of a main pressure pneumatic overload protection system provided by an embodiment of the present invention.

[0030] Specifically, 1-main pressure pneumatic overload protection system; 101-main pressure cylinder; 102-main pressure cylinder piston; 103-second air inlet connector; 104-first position detection sensor; 105-second exhaust connector; 106-first cylinder flange; 107-first pin shaft; 108-first rolling bearing; 109-first fixing flange; 110-nut; 111-first extension rod; 112-first fixing seat; 113-main pressure strain gauge; 114-first hydraulic tensioning sleeve; 115-strain gauge cable; 116-second pin shaft; 117-fourth rolling bearing;

[0031] 2-main pressing wheel assembly; 201-main pressing wheel; 202-end cover; 203-second rolling bearing; 204-main pressing shaft; 204A-main pressing shaft rotation center; 204B-main pressing wheel rotation center; 205-third rolling bearing; 206-main pressing end cover; 207-thrust bearing;

[0032] 301-top tower; 302-turret;

[0033] 4-Lower main pressure wheel;

[0034] 5-pneumatic control assembly; 501-first air inlet connector; 502-check valve; 503-air storage tank; 504-one-two connector; 505-main pressure high-precision pressure regulating valve; 505A-main pressure air pressure signal connector; 505B-pressure regulating valve operation panel; 505C-pressure regulating knob; 506-pre-pressure high-precision pressure regulating valve; 506A-pre-pressure air pressure signal connector; 5A-system air supply pipeline; 5B-main pressure air supply pipeline; 5C-pre-pressure air supply pipeline;

[0035] 6-Pre-pressure pneumatic overload protection system;

[0036] 7-Pre-pressing wheel assembly;

[0037] 8-lower pre-pressing wheel;

[0038] 9-stamping die; 91-upper punch; 92-middle die; 93-lower punch. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0041] As shown in FIG1 , an overload protection mechanism based on a tablet press comprises: a frame and a top tower 301 arranged on the frame, a turret 302, a pneumatic control assembly 5, a main pressure pneumatic overload protection system 1 and a pre-pressure pneumatic overload protection system 6. The main pressure wheel assembly 2 and the pre-pressure wheel assembly 7 are both arranged above the turret 302, and a stamping die 9 is installed on the turret 302, and the stamping die 9 is used to stamp powder.

[0042] As shown in Figure 2, the main pressure pneumatic overload protection system 1 includes: a main pressure cylinder 101 rotatably connected to the frame, the main pressure cylinder 101 is connected to the main pressure wheel assembly 2 through the main pressure cylinder piston 102. During the operation of the equipment, when the force applied to the main pressure wheel assembly 2 exceeds the set pressure, the main pressure wheel assembly 2 will transfer the force applied to the main pressure cylinder 101. According to the force applied to the main pressure wheel assembly 2, the main pressure cylinder 101 quickly drives the main pressure wheel assembly 2 to a certain height through the main pressure cylinder piston 102, effectively avoiding damage to core components such as the stamping die 9, pressure wheel, turret 302 in the tablet press due to overload.

[0043] At the same time, the pre-pressing pneumatic overload protection system 6 includes: a pre-pressing cylinder, which is rotatably connected to the frame, and the pre-pressing cylinder is connected to the pre-pressing wheel assembly 7 through the pre-pressing cylinder piston. When the force applied to the pre-pressing wheel assembly 7 exceeds the set pressure, the pre-pressing wheel assembly 7 will transfer the force applied to the pre-pressing cylinder. According to the force applied to the pre-pressing wheel assembly 7, the pre-pressing cylinder quickly drives the pre-pressing wheel assembly 7 to a certain height through the main pressure cylinder piston 102, thereby further avoiding damage to core components such as the stamping die 9, pressing wheel, turret 302 in the tablet press due to overload.

[0044] It should be noted that the main pressure cylinder 101 and the pre-pressure cylinder will not have the problem of response delay, and can better realize real-time protection of core components such as molds, pressure wheels, and turrets 302.

[0045] The pneumatic control component 5 includes: an air tank 503, which is mainly used to store compressed air. The air tank 503 can be used to quickly replenish the main pressure cylinder 101 and the pre-pressure cylinder to ensure the stability of the air pressure of the rear-end air-using components. The air tank 503 is connected to the main pressure cylinder 101 through the main pressure air supply pipeline 5B, and the air tank 503 is connected to the pre-pressure cylinder through the pre-pressure air supply pipeline 5C. When the main pressure cylinder 101 and the pre-pressure cylinder need to be restored to their initial positions after being overloaded, the compressed air is respectively replenished to the main pressure cylinder 101 and the pre-pressure cylinder through the air tank 503. In addition, a system air supply pipeline 5A is set at the lower end of the air tank 503, and compressed air is transported to the air tank 503 through the system air supply pipeline 5A to ensure that the compressed air in the air tank 503 is always sufficient, further ensuring the stability of the air pressure of the rear-end air-using components.

[0046] It should be noted that the pressure of the gas storage tank 503 is higher than the pressure of the main pressure cylinder 101 and the pre-pressure cylinder, so there will be no excessive pressure drop and untimely gas replenishment during the gas replenishment process.

[0047] When in use, while the turret 302 rotates at high speed, the main pressing wheel assembly 2 and the pre-pressing wheel assembly 7 cooperate with the stamping die 9 to complete the stamping of the powder. When the force exerted by the stamping die 9 on the main pressing wheel assembly 2 exceeds the set pressure, the main pressing wheel assembly 2 will transfer the force exerted on it to the main pressing cylinder 101. According to the force exerted on the main pressing wheel assembly 2, the main pressing cylinder 101 quickly drives the main pressing wheel assembly 2 to a certain height through the main pressing cylinder piston 102. When the force exerted by the stamping die 9 on the pre-pressing wheel assembly 7 exceeds the set pressure, the pre-pressing wheel assembly 7 will transfer the force exerted on it to the pre-pressing cylinder. According to the force exerted on the pre-pressing wheel assembly 7, the pre-pressing cylinder quickly drives the pre-pressing wheel assembly 7 to a certain height through the pre-pressing cylinder piston. This prevents the core components such as the stamping die 9, pressing wheel, and turret 302 in the tablet press from being damaged due to overload.

[0048] As shown in Figure 3, the upper end of the air storage tank 503 is connected to a two-way joint 504, the first end of the two-way joint 504 is connected to a main pressure high-precision pressure regulating valve 505, and the main pressure high-precision pressure regulating valve 505 is connected to the main pressure pneumatic overload protection system 1 through the main pressure air supply pipeline 5B. Specifically, the upper end of the main pressure cylinder 101 is provided with a second air inlet joint 103, and the main pressure high-precision pressure regulating valve 505 is connected to the second air inlet joint 103 through the main pressure air supply pipeline 5B. The set pressure of the main pressure wheel assembly 2 can be accurately adjusted through the main pressure high-precision pressure regulating valve 505, and correspondingly, the upper end of the main pressure cylinder 101 is provided with a second exhaust joint 105. The second exhaust connector 105 discharges the compressed air inside the main pressure cylinder 101, and the second end of the one-to-two connector 504 is connected to the pre-pressure high-precision pressure regulating valve 506, and the pre-pressure high-precision pressure regulating valve 506 is connected to the pre-pressure pneumatic overload protection system 6 through the pre-pressure air supply pipeline 5C. Specifically, a third air inlet connector is provided at the upper end of the pre-pressure cylinder, and the pre-pressure high-precision pressure regulating valve 506 is connected to the third air inlet connector through the pre-pressure air supply pipeline 5C. The set pressure of the pre-pressure wheel assembly 7 can be accurately adjusted through the pre-pressure high-precision pressure regulating valve 506, and correspondingly, a third exhaust connector is provided at the upper end of the pre-pressure cylinder, and the compressed air inside the pre-pressure cylinder is discharged through the third exhaust connector.

[0049] By setting the pressure in advance through the main pressure high-precision pressure regulating valve 505 and the pre-pressure high-precision pressure regulating valve 506, the overload protection force can be flexibly adjusted, and the overall overload protection mechanism can be adapted to various working scenarios. It should be noted that the set pressure is less than the pressure on the main pressure roller assembly 2 and the pre-pressure roller assembly before the core components such as the mold, the pressure roller, and the turret 302 are damaged due to overload.

[0050] In one embodiment of the present invention, a one-way valve 502 is provided at the lower end of the gas storage tank 503, wherein the upper end of the gas inlet joint and the system gas supply pipeline 5A are connected to the first gas inlet joint 501, the one-way valve 502 is connected to the first gas inlet joint 501, and the lower end of the system gas supply pipeline 5A is connected to the gas source of the tablet press, and the gas source delivers compressed air to the gas storage tank 503 through the system gas supply pipeline 5A. It should be noted that when other components of the equipment consume gas, a pressure drop will occur, which will affect the compressed air pressure of the system gas supply pipeline 5A, and the extreme In this case, the pressure of the main pressure pneumatic overload protection system 1 will be too low and the equipment cannot work normally. The one-way valve 502 is used to limit the compressed air to enter the air storage tank 503 only from the system air supply pipeline 5A, but not from the air storage tank 503 to enter the system air supply pipeline 5A. This can avoid the situation where the 5A system air supply pressure suddenly decreases, which causes the main pressure pneumatic protection system and the pre-pressure pneumatic overload protection system 6 to fail to work, so as to ensure the stability of the air supply pressure of the main pressure pneumatic overload protection system 1 and the pre-pressure pneumatic overload protection system 6.

[0051] Both the main pressure high-precision pressure regulating valve 505 and the pre-pressure high-precision pressure regulating valve 506 are provided with a pressure regulating valve operation screen 505B, and the display accuracy of the pressure regulating valve operation screen 505B is 0.001Mpa. The two pressure regulating valve operation screens 505B are used to display the pressure of the main pressure high-precision pressure regulating valve 505 and the pre-pressure high-precision pressure regulating valve 506 respectively, and the two pressure regulating valve operation screens 505B are both connected to the control system by signal, and the control system signal is connected to the main pressure high-precision pressure regulating valve 505 and the pre-pressure high-precision pressure regulating valve 506, and instructions can be issued to the control system through the pressure regulating valve operation screen 505B, and then the main pressure high-precision pressure regulating valve 505 and the pre-pressure high-precision pressure regulating valve 506 are adjusted through the control system.

[0052] Among them, the main pressure high-precision pressure regulating valve 505 and the pre-pressure high-precision pressure regulating valve 506 can realize independent adjustment of the set pressure of the main pressure protection force and the pre-pressure protection force. The main pressure high-precision pressure regulating valve 505 is provided with a main pressure air pressure signal connector 505A, and the pressure regulating valve operation screen 505B outputs an electrical signal to the outside through the main pressure air pressure signal connector 505A, and feeds back the current pressure of the main pressure high-precision pressure regulating valve 505 to the control system. In addition, the main pressure high-precision pressure regulating valve 505 is provided with a pressure regulating knob 505C, and by turning the pressure regulating knob 505C, the pressure of the output air pressure of the main pressure high-precision pressure regulating valve 505 can be adjusted, and the adjustment accuracy is 0.001Mpa.

[0053] At the same time, the main pressure high-precision pressure regulating valve 505 and the pre-pressure high-precision pressure regulating valve 506 both have pressure switch functions. When there is no pressure in the compressed air system, an alarm signal will be generated and fed back to the control system to achieve alarm shutdown.

[0054] In one embodiment of the present invention, a preset program can also be written into the control system, and the system control automatically calculates the corresponding current overload protection force according to the main pressure high-precision pressure regulating valve 505 or the pre-pressure high-precision pressure regulating valve 506, and displays it in the control system. In specific applications, if the current system only needs to protect the main pressure, choose to stop enabling the relevant preset program of the pre-pressure overload protection system. If the current system has two main pressures or two pre-pressures, add a one-to-two joint 504 to the main pressure air supply pipeline 5B or the pre-pressure air supply pipeline 5C to provide compressed air for the main pressure cylinder 101 or the pre-pressure cylinder.

[0055] It should be noted that the pre-pressure high-precision pressure regulating valve 506 is provided with a pre-pressure air pressure signal connector and a corresponding pressure regulating knob, that is, the pre-pressure high-precision pressure regulating valve 506 has the same function as the main pressure high-precision pressure regulating valve 505 .

[0056] As shown in FIG4 , in one embodiment of the present invention, a turret 302 is provided in the tablet press, and a punching die 9 is provided on the turret 302, and the punching die 9 includes: an upper punch 91, a middle die 92 and a lower punch 93 arranged sequentially from top to bottom, and a drive shaft is coaxially arranged at the axis position of the turret 302, and the drive shaft rotates with the drive turret 302, wherein a plurality of die cavities are arranged in an array on the top surface of the middle die 92, and the upper punch 91 can move up and down in the turret 302, and the lower punch 93 can move up and down in the turret 302, and the upper punch 91 and the lower punch 93 enter the die cavity to extrude the powder. The above features are relatively mature prior art, so they are not described in detail.

[0057] As shown in Figures 5 and 6, a top tower 301 is arranged on the frame, and the top tower 301 is connected to the first fixed flange 109, and the first fixed flange 109 is rotatably connected to the first cylinder flange 106. Specifically, the first cylinder flange 106 is connected to the first fixed flange 109 through the first pin shaft 107, and the first rolling bearing 108 is arranged on the outer peripheral side of the first pin shaft 107, and the first pin shaft 107 can rotate freely relative to the first rolling bearing 108, wherein the first rolling bearing 108 can select a needle bearing or a cylindrical roller bearing, and a fourth rolling bearing 117 is arranged between the first fixed seat 112 and the main pressure strain gauge 113, and the fourth rolling bearing 117 can select a needle bearing or a cylindrical roller bearing, so as to reduce the friction between the first fixed seat 112 and the main pressure strain gauge 113, and further increase the response speed of the overload protection of the main pressure cylinder 101.

[0058] It should be noted that when the force applied to the main pressure wheel 201 reaches the limit value, the first fixed seat 112 rotates relative to the main pressure strain gauge 113. Similarly, when the force applied to the first fixed seat 112 reaches the limit value, the first fixed flange 109 can rotate relative to the first cylinder flange 106, thereby effectively ensuring the stability of the main pressure wheel 201 when pressing the stamping die 9.

[0059] In addition, the first cylinder flange 106 is connected to the main pressure cylinder 101 through a plurality of bolt rods, the main pressure cylinder 101 is connected to the first fixing seat 112 through the main pressure cylinder piston 102, and the first fixing seat 112 is connected to the main pressure strain gauge 113, which is used to detect the pressure on the main pressure wheel assembly 2. Among them, a Wheatstone bridge strain gauge is attached to the main pressure strain gauge 113, and the electrical signal feeds back the pressure signal to the control system through the strain gauge cable 115.

[0060] The main pressing wheel assembly 2 includes: a main pressing shaft 204, which is an eccentric shaft. A first hydraulic tensioning sleeve 114 is arranged on the outer peripheral side of the main pressing shaft 204. The first hydraulic tensioning sleeve 114 is connected to the main pressure strain gauge 113. A main pressing wheel 201 is arranged on the outer peripheral side of the main pressing shaft 204. The main pressing wheel 201 is used to press the stamping die 9. Specifically, the main pressing wheel 201 is used to press the upper punch 91 directly below it. It should be noted that when the first hydraulic tensioning sleeve 114 is in a tensioned state, the main pressure shaft 204 is fixedly connected to the main pressure strain gauge 113. At this time, the main pressure shaft 204 cannot rotate relative to the main pressure strain gauge 113. When the main pressure wheel 201 is subjected to force, the main pressure shaft 204 generates torque, which is transmitted to the main pressure strain gauge 113 through the first hydraulic tensioning sleeve 114. The torque is converted into an upward thrust at the position of the first fixed seat 112, and the thrust is finally borne by the main pressure cylinder 101; when the first hydraulic tensioning sleeve 114 is in a loosened state, the main pressure shaft 204 is rotatably connected to the main pressure strain gauge 113.

[0061] The main pressure wheel 201 is radially fixed to the main pressure wheel rotation center 204B on the main pressure shaft 204 through the third rolling bearing 205. The main pressure wheel 201 is further axially fixed to the main pressure wheel rotation center 204B through two end covers 202 and a thrust bearing 207. The main pressure shaft 204 is connected to the assembly shell through the second rolling bearing 203 and the third rolling bearing 205. The second rolling bearing 203 and the third rolling bearing 205 can be selected as needle bearings or cylindrical roller bearings to reduce the friction of the main pressure shaft 204 rotating along the main pressure shaft rotation center 204A, improve the detection accuracy of the main pressure strain gauge 113, and improve the response time of the signal in the strain gauge cable 115.

[0062] In addition, a main pressure end cover 206 is provided at the right end of the assembly housing, and the main pressure end cover 206 is connected to the main pressure strain gauge 113 through the first hydraulic tension sleeve 114. At this time, the main pressure shaft 204 rotates along the main pressure shaft rotation center 204A. When the main pressure wheel 201 is subjected to a force in the direction of 201F, the force will act on the main pressure wheel rotation center 204B. At this time, the main pressure shaft 204 will generate torque along the main pressure shaft rotation center 204A, and the torque will be transmitted to the main pressure strain gauge 113 through the first hydraulic tension sleeve 114, and the force will be applied to the first fixed seat 112 through the first pin 107 and the rolling bearing. The force acts on the main pressure cylinder piston 102 through the first extension rod 111 and the nut 110. That is, the force of the stamping die 9 finally acts on the main pressure cylinder piston 102, and the direction of the force finally acting on the main pressure cylinder 101 is 102A.

[0063] It should be noted that when the main pressure cylinder piston 102 moves upward along the direction 102A, the compressed air pressure inside the main pressure cylinder 101 increases and acts on the main pressure air supply pipeline 5B of the main pressure high-precision pressure regulating valve 505. The output side pressure of the main pressure high-precision pressure regulating valve 505, that is, the side of the main pressure air supply pipeline 5B, cannot be higher or lower than the set pressure of the main pressure high-precision pressure regulating valve 505. When the main pressure air supply pipeline 5B increases, the high-precision pressure regulating valve will automatically exhaust and release pressure to keep the pressure of the main pressure air supply pipeline 5B the same as the set pressure of the main pressure high-precision pressure regulating valve 505. When the pressure of the main pressure air supply pipeline 5B decreases, the high-precision pressure regulating valve will automatically replenish air to keep the pressure of the main pressure air supply pipeline 5B the same as the set pressure of the main pressure high-precision pressure regulating valve 505, so as to ensure that the main pressure wheel assembly 2 and the pre-pressure wheel assembly 7 can stably assist the stamping die 9 in stamping the powder stably.

[0064] When the depth of the upper punch 91 at the position of the main pressing wheel 201 needs to be adjusted, the first hydraulic tension sleeve 114 is adjusted to the loose state, and the main pressing shaft 204 can rotate freely relative to the main pressure strain gauge 113; the upper main pressing shaft 204 is rotated by a certain angle, the height position of the rotation center of the pressing wheel changes, and the height position of the main pressing wheel 201 coaxially arranged at the rotation center of the pressing wheel changes until the height position of the upper punch 91 reaches the set position, and the adjustment of the depth of the upper punch 91 is completed; when the adjustment of the depth of the upper punch 91 is completed, the first hydraulic tension sleeve 114 is adjusted to the tightened state, and the main pressing shaft 204 and the first hydraulic tension sleeve 114 are fixedly connected to transmit torque normally. That is, when adjusting the depth of the upper punch 91, it is only necessary to loosen and tighten the first hydraulic tension sleeve 114, which is convenient to operate and saves operation time. Moreover, when adjusting the depth of the upper punch 91, the support position of the main pressure strain gauge 113 will not change, so there will be no problem of inaccurate main pressure signal.

[0065] The top tower 301 is connected to the second fixed flange, and the second fixed flange is rotatably connected to the second cylinder flange. Specifically, the second cylinder flange is connected to the second fixed flange through the second pin shaft 116, and the second rolling bearing 203 is arranged on the outer peripheral side of the second pin shaft 116. The second pin shaft 116 can rotate freely relative to the second rolling bearing 203. The second cylinder flange is connected to the pre-stress cylinder through a plurality of bolt rods, and the pre-stress cylinder is connected to the second fixed seat through the pre-stress cylinder piston. The second fixed seat is connected to the pre-stress strain gauge, and the pre-stress strain gauge is used to detect the pressure on the pre-stress wheel assembly 7. Among them, the pre-stress strain gauge is also pasted with a Wheatstone bridge strain gauge, and the electrical signal feeds back the pressure signal to the control system through the strain gauge cable 115.

[0066] The pre-stressing wheel assembly 7 includes: a pre-stressing shaft, a second hydraulic tensioning sleeve is arranged on the outer peripheral side of the pre-stressing shaft, the second hydraulic tensioning sleeve is connected to the pre-stressing strain gauge, a pre-stressing wheel is arranged on the outer peripheral side of the pre-stressing shaft, and the pre-stressing wheel is used to press the stamping die 9, specifically, the pre-stressing wheel is used to press the upper punch 91 directly below it. It should be noted that when the second hydraulic tensioning sleeve is in a tensioned state, the pre-stressing shaft is fixedly connected to the pre-stressing strain gauge; when the second hydraulic tensioning sleeve is in a loosened state, the pre-stressing shaft is rotatably connected to the pre-stressing strain gauge. Furthermore, the step of adjusting the depth of the upper punch 91 at the position of the pre-stressing wheel is the same as the step of adjusting the depth of the upper punch 91 at the position of the main pressing wheel 201, so it will not be described in detail.

[0067] In addition, a first extension rod 111 is provided at the bottom end of the main pressure cylinder piston 102, and the main pressure cylinder piston 102 is connected to the first fixing seat 112 through the first extension rod 111. Similarly, a second extension rod is provided at the bottom end of the pre-pressure cylinder piston, and the pre-pressure cylinder piston is connected to the second fixing seat through the second extension rod. The length of the first extension rod 111 and the length of the second extension rod are set according to the requirements to ensure that the main gear assembly can stably press the upper punch 91 at the corresponding position directly below.

[0068] A first position detection sensor 104 is provided on the side of the main pressure cylinder 101. The first position detection sensor 104 is used to detect the position state of the main pressure cylinder piston 102. When an overload state occurs, the first position detection sensor 104 can detect the movement of the piston along the direction 102A, and feed back an alarm signal to the control system, which is further processed by the control system. At the same time, a second position detection sensor is provided on the side of the pre-pressure cylinder. The second position detection sensor is used to detect the position state of the pre-pressure cylinder piston. When the position of the main pressure cylinder piston 102 or the position of the pre-pressure cylinder piston changes, the first position detection sensor 104 and the second position detection sensor can respectively quickly feed back the detected data to the control system, which is further processed by the control system.

[0069] It should be noted that both the first position detection sensor 104 and the second position detection sensor are kept in a normally closed state. When the first position detection sensor 104 detects the position of the main pressure cylinder piston 102, the contact is opened and an alarm signal is given. When the entire cable of the first position detection sensor 104 is damaged, or the plug is not connected, or the position of the first position detection sensor 104 is incorrect, the control system is always in a normally open alarm signal, which effectively improves the safety of the equipment.

[0070] As shown in Fig. 4 and Fig. 5, a first air inlet connector 501 is provided on the main pressure cylinder 101, and the first air inlet connector 501 is connected to the main pressure high-precision pressure regulating valve 505 through the main pressure air supply pipeline 5B. The main pressure high-precision pressure regulating valve 505 provides compressed air of a certain pressure to the main pressure cylinder piston 102, wherein the compressed air pressure in the main pressure cylinder 101 is the output pressure of the main pressure high-precision pressure regulating valve 505, and the compressed air pushes the main pressure cylinder piston 102 to generate a thrust along the direction 102B. When the thrust generated by the compressed air is greater than the thrust generated by the force 201F acting on the main pressure cylinder piston 102, the pressing wheel is in a normal state, providing a supporting force for the stamping die 9 to press the tablet. When the thrust generated by the compressed air is less than the thrust generated by 201F acting on the main pressure cylinder piston 102, it is an overload state, and the main pressure cylinder piston 102 will move upward along the direction 102A, and the first extension rod 111 and the first fixed seat 112 connected to the main pressure cylinder piston 102 will move upward. At this time, the main pressure strain gauge 113 will rotate along the main pressure axis rotation center 204A, and the pressure roller rotation center will rotate upward along the main pressure roller rotation center 204B. Since the main pressure roller 201 is coaxial with the main pressure roller rotation center 204B, the main pressure roller 201 will move upward. At the same time, the first fixed seat 112 and the main pressure strain gauge 113 will produce relative rotation, the first fixed flange 109 and the first cylinder flange 106 will produce relative rotation, and the main pressure cylinder piston 102 will move with multiple degrees of freedom to reduce the impact force on itself. When the overload state ends, the main pressure cylinder piston 102 will automatically move downward along the direction 102B to the lowest position and return to the initial state.

[0071] As shown in Figure 1, a lower main pressing wheel 4 and a lower pre-pressing wheel 8 are arranged below the stamping die 9, wherein the lower main pressing wheel 4 is arranged directly below the main pressing wheel 201, and the lower pre-pressing wheel 8 is arranged directly below the pre-pressing wheel. The pre-pressing wheel presses the upper punch 91, and the lower pre-pressing wheel 8 presses the lower punch 93, so that the powder filled in the mold cavity is preliminarily extruded. Further, the main pressing wheel 201 presses the upper punch 91, and the lower main pressing wheel 4 presses the lower punch 93, so that the powder filled in the mold cavity is extruded again. The upper punch 91 finally transmits the pressure to the main pressure pneumatic protection system through the main pressing wheel assembly 2, and finally transmits it to the top tower 301.

[0072] In one embodiment of the present invention, guide rail grooves are provided on the side of the main pressure cylinder 101 and the side of the pre-pressure cylinder, and the first position detection sensor 104 and the second position detection sensor are respectively slidably connected to the corresponding guide rail grooves. The first position detection sensor 104 and the second position detection sensor can be fixed at different positions of the guide rail grooves according to different working conditions, and the positions of the first position detection sensor 104 and the second position detection sensor can be flexibly adjusted, thereby improving the overall application range of the first position detection sensor 104 and the second position detection sensor.

[0073] In the second embodiment of the present invention, the first position detection sensor 104 selects a normally closed contact, and the first position detection sensor 104 is adjusted to the highest point along the direction of 102A, that is, when the main pressure cylinder piston 102 runs to the extreme position along the direction of 102A, the first position detection sensor 104 can generate an alarm signal. When the main pressure cylinder piston 102 is within the entire stroke range, except for the highest point position, the first position detection sensor 104 will not generate an alarm signal at other positions. When the constant pressure pressing function is used, the main pressure cylinder 101 generates a fixed thrust through the main pressure high-precision pressure regulating valve 505, and a constant thrust is applied to the main pressure wheel 201 through the main pressure overload protection system and the main pressure wheel assembly 2. During the tableting process, the upper punch 91 exerts a thrust on the main pressure wheel 201 along the direction 201F. When the thrust of the upper punch 91 is about to exceed the set pressure, it will push the main pressure wheel 201 upward, and finally push the main pressure cylinder piston 102 upward, so as to achieve the constant force on the upper punch 91, and finally achieve the constant pressure tableting function of the main pressure overload protection system. The so-called constant pressure tableting function is to adjust the pressure during constant pressure tableting by adjusting the main pressure high-precision pressure regulating valve 505, and provide a constant tableting force for the main pressure wheel 201, and do not provide a tableting force higher than the set pressure. Similarly, the constant pressure tableting function of the pre-pressure overload protection system can also be achieved by adopting the above method to the pre-pressure pneumatic overload protection system 6.

[0074] When the present invention is used, while the turret 302 rotates at high speed, the main pressing wheel assembly 2 and the pre-pressing wheel assembly 7 cooperate with the stamping die 9 to complete the stamping of the powder. When the force exerted by the stamping die 9 on the main pressing wheel 201 exceeds the set pressure, the main pressing wheel 201 transfers the force exerted on it to the main pressing cylinder 101 through the first hydraulic tension sleeve 114 and the main pressure strain gauge 113. According to the force exerted on the main pressing wheel 201, the main pressure cylinder 101 quickly drives the first fixed seat 112 to rise to a certain height through the main pressure cylinder piston 102. The first fixed seat 1 12 drives the main pressure wheel 201 to quickly rise to a certain height through the main pressure strain gauge 113 and the first hydraulic tensioning sleeve 114. When the force exerted on the pre-pressing wheel by the stamping die 9 exceeds the set pressure, the pre-pressing wheel will transfer the force exerted on it to the pre-pressing cylinder through the second hydraulic tensioning sleeve and the pre-pressing strain gauge. According to the force exerted on the pre-pressing wheel, the pre-pressing cylinder quickly drives the first fixed seat 112 to rise to a certain height through the pre-pressing cylinder piston. The first fixed seat 112 drives the pre-pressing wheel to quickly rise to a certain height through the pre-pressing strain gauge and the second hydraulic tensioning sleeve.

[0075] In summary, the main pressure pneumatic overload protection system 1 and the pre-pressure pneumatic overload protection system 6 are used to protect the core components of the tablet press, such as the stamping die 9, the pressing wheel, the turret 302, etc., from being damaged due to overload. Moreover, the set pressure is adjusted by the main pressure high-precision pressure regulating valve 505 and the pre-pressure high-precision pressure regulating valve 506, and the overload force has the advantage of linear adjustment. When the equipment is overloaded and exceeds the set pressure, the main pressure cylinder piston 102 will immediately act to complete the protection. There is no response time, and the overload protection responds quickly, which can better achieve real-time protection. It is suitable for high-speed and high-pressure production environments of tablet presses and occasions with constant pressure tableting requirements. The structure has a good protection effect on the mold and the pressing wheel.

[0076] It should be noted that, in this specification, relational terms such as first and second are merely used to distinguish one entity from other entities, but do not necessarily require or imply any actual relationship or order between these entities.

[0077] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core ideas of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. An overload protection mechanism based on a tablet press, characterized in that: include: frame; A turret is rotatably arranged on the frame, a main pressing wheel assembly and a pre-pressing wheel assembly are arranged above the turret, and a stamping die is installed on the turret, and the stamping die is used for stamping powder; The main pressure pneumatic overload protection system comprises: a main pressure cylinder rotatably connected to the frame, the main pressure cylinder being connected to the main pressure wheel assembly via a main pressure cylinder piston; The pre-pressing pneumatic overload protection system comprises: a pre-pressing cylinder rotatably connected to the frame, the pre-pressing cylinder being connected to the pre-pressing wheel assembly via a pre-pressing cylinder piston; The pneumatic control component includes: an air tank, which is connected to the main pressure pneumatic overload protection system through a main pressure air supply pipeline, and the air tank is connected to the pre-pressure pneumatic overload protection system through a pre-pressure air supply pipeline, and the air tank is used to store compressed air.

2. The overload protection mechanism based on a tablet press according to claim 1, characterized in that: The upper end of the gas storage tank is connected to a two-way joint, a first end of the two-way joint is connected to a main pressure high-precision pressure regulating valve, and the main pressure high-precision pressure regulating valve is connected to the main pressure pneumatic overload protection system through a main pressure air supply pipeline, and the second end of the two-way joint is connected to a pre-pressure high-precision pressure regulating valve, and the pre-pressure high-precision pressure regulating valve is connected to the pre-pressure pneumatic overload protection system through a pre-pressure air supply pipeline.

3. An overload protection mechanism based on a tablet press according to claim 2, characterized in that: A one-way valve is arranged at the lower end of the gas storage tank, and the one-way valve is connected to the gas source through the system gas supply pipeline.

4. The overload protection mechanism based on a tablet press according to claim 3, characterized in that: The main pressure high-precision pressure regulating valve and the pre-pressure high-precision pressure regulating valve are both provided with pressure regulating valve operation screens, and the two pressure regulating valve operation screens are respectively used to display the pressures of the main pressure high-precision pressure regulating valve and the pre-pressure high-precision pressure regulating valve, and both the pressure regulating valve operation screens are signal-connected to the control system.

5. An overload protection mechanism based on a tablet press according to any one of claims 1 to 4, characterized in that: The frame is connected to the first fixed flange, the first fixed flange is rotatably connected to the first cylinder flange, the first cylinder flange is connected to the main pressure cylinder, the main pressure cylinder is connected to the first fixed seat through the main pressure cylinder piston, the first fixed seat is connected to the main pressure strain gauge, and the pre-pressure strain gauge is used to detect the pressure exerted on the main pressure wheel assembly.

6. The overload protection mechanism based on a tablet press according to claim 5, characterized in that: The main pressure wheel assembly includes: a main pressure shaft, a first hydraulic tension sleeve is arranged on the outer peripheral side of the main pressure shaft, the first hydraulic tension sleeve is connected to the main pressure strain gauge, and a main pressure wheel is arranged on the outer peripheral side of the main pressure shaft, and the main pressure wheel is used to press the stamping die.

7. An overload protection mechanism based on a tablet press according to any one of claims 1 to 4, characterized in that: The frame is connected to the second fixed flange, the second fixed flange is rotatably connected to the second cylinder flange, the second cylinder flange is connected to the pre-stressing cylinder, the pre-stressing cylinder is connected to the second fixed seat through the pre-stressing cylinder piston, the second fixed seat is connected to the pre-stressing strain gauge, and the pre-stressing strain gauge is used to detect the pressure exerted on the pre-stressing wheel assembly.

8. An overload protection mechanism based on a tablet press according to claim 7, characterized in that: The pre-pressing wheel assembly includes: a pre-pressing shaft, a second hydraulic tensioning sleeve is arranged on the outer peripheral side of the pre-pressing shaft, the second hydraulic tensioning sleeve is connected to the pre-pressure strain gauge, and a pre-pressing wheel is arranged on the outer peripheral side of the pre-pressing shaft, and the pre-pressing wheel is used to press the stamping die.

9. The overload protection mechanism based on a tablet press according to claim 5, characterized in that: A first position detection sensor is provided on the side of the main pressure cylinder, and the first position detection sensor is used to detect the position state of the main pressure cylinder piston; a second position detection sensor is provided on the side of the pre-pressure cylinder, and the second position detection sensor is used to detect the position state of the pre-pressure cylinder piston.

10. An overload protection mechanism based on a tablet press according to any one of claims 1 to 4, characterized in that: A lower main pressing wheel and a lower pre-pressing wheel are arranged below the stamping die, wherein the lower main pressing wheel is arranged directly below the main pressing wheel, and the lower pre-pressing wheel is arranged directly below the pre-pressing wheel.

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