Automatic injection molding part taking manipulator and part taking stroke control method

Abstract

The invention discloses an automatic injection molding part taking manipulator and a part taking stroke control method. The automatic injection molding part taking manipulator comprises a base, a part suction seat is installed on the front face of the base in an embedded mode, a part groove matched with an injection molding part is formed in the front face of the part suction seat, and an angle adjusting mechanism is arranged on the back face of the base; the mechanical arm further comprises a negative pressure mechanism, the negative pressure mechanism comprises a negative pressure cavity formed in the base and first through holes communicated with the negative pressure cavity, the negative pressure cavity is communicated with external negative pressure equipment, and second through holes in one-to-one correspondence with the first through holes are formed in the suction piece base. The front face of the part suction base is aligned with the injection part and enables the injection part to be embedded into the part groove, the negative pressure equipment enables the negative pressure cavity to form negative pressure, and the injection part is sucked through the negative pressure under communication of the first through hole and the second through hole and attached to the part groove. The negative-pressure automatic part taking mode is adopted, excessive pressure cannot be applied to the injection molding part, and therefore damage to the injection molding part can be effectively reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of manipulators, and in particular relates to an automatic injection molded part picking manipulator and a picking stroke control method. Background Art

[0002] Injection molding is an important process widely used in the production of plastic products in modern manufacturing. With the continuous development of automation technology, robots have become an indispensable equipment in injection molding production lines, responsible for taking out hot injection molded parts from molds. Although existing technologies have made certain progress in improving production efficiency and reducing labor costs, there are still some problems that need to be solved.

[0003] When existing manipulators clamp hot injection molded parts, they often use traditional clamping methods, which can easily cause damage to the injection molded parts during the execution process. The main reasons include the following:

[0004] 1. Excessive clamping force: The clamping force of existing manipulators is relatively rough during the clamping process and cannot be flexibly adjusted according to the material and shape of the injection molded parts. As a result, the manipulator may exert excessive pressure on the injection molded parts during the clamping process, causing surface scratches or shape deformation;

[0005] 2. Influence of heat conduction: The temperature of the injection molded parts is high when they are ejected from the mold. The clamping part of the existing manipulator often does not consider the influence of heat conduction on the material properties. When the manipulator clamps the hot parts, it may cause local overheating of the material, thereby affecting the physical properties and appearance of the injection molded parts;

[0006] 3. Insufficient motion trajectory control: In existing control systems, the motion trajectory design of the robot is often relatively simple and cannot effectively adapt to injection molded parts of different shapes and sizes. Instability during movement may lead to improper clamping and aggravate damage to the injection molded parts.

[0007] In summary, the problem in the prior art that hot injection molded parts are easily damaged by the robot gripping them needs to be solved urgently. Summary of the invention

[0008] The present invention aims at solving the problems in the prior art and proposes the following technical solutions:

[0009] The automatic take-out robot for injection molded parts comprises a base, a suction seat is embedded in the front of the base, a slot matching the injection molded parts is provided on the front of the suction seat, and an angle adjustment mechanism is provided on the back of the base;

[0010] The manipulator further includes a negative pressure mechanism, which includes a negative pressure cavity opened inside the base and a through hole 1 connected thereto, the negative pressure cavity is connected to an external negative pressure device, and a through hole 2 corresponding to the through hole 1 is opened on the suction seat;

[0011] The front side of the suction seat is aligned with the injection molded part and embeds it into the part groove. The negative pressure device forms a negative pressure in the negative pressure cavity. When through hole one and through hole two are connected, the negative pressure absorbs the injection molded part and fits it into the part groove.

[0012] As a preferred embodiment of the above technical solution, a foundation pit is opened on the front side of the base, and the foundation pit and the suction piece seat are matched.

[0013] As a preferred embodiment of the above technical solution, a fixing part is integrally fixedly connected to the suction seat, a mounting groove matched with the fixing part is provided on the front side of the base, and the fixing part is fixedly installed on the mounting groove by bolts.

[0014] As a preferred embodiment of the above technical solution, a three-way pipe is installed on the outer wall of the base, one end of the three-way pipe is connected to the negative pressure chamber, and the other two ends of the three-way pipe are respectively installed with a connecting pipe and a solenoid valve.

[0015] As a preferred embodiment of the above technical solution, the angle adjustment mechanism includes a fixing plate fixedly connected to the back of the base, a column rod is fixedly connected to the other side of the fixing plate, both ends of the column rod are jointly rotatably sleeved with an adapter seat, and a driving assembly is arranged on the adapter seat.

[0016] As a preferred embodiment of the above technical solution, a mechanical arm is fixedly connected to a side of the adapter away from the base.

[0017] As a preferred embodiment of the above technical solution, the driving assembly includes a motor fixedly mounted on an adapter, the output shaft of the motor is fixedly connected to a rotating shaft, the other end of the rotating shaft is fixedly connected to a gear plate 1, one end of the column rod is fixedly connected to a gear plate 2, and gear plate 2 and gear plate 1 are meshing for transmission.

[0018] A method for controlling a pickup stroke, the method for controlling a pickup stroke is applied to the above-mentioned automatic pickup robot for injection molded parts, and the method for controlling a pickup stroke comprises the following steps:

[0019] S1, pre-assembly stage: select a suction seat that matches the injection molded part, and install the back of the suction seat in the foundation pit on the front of the base in an embedded manner. During installation, align the fixing part with the installation groove and fix it with bolt threads;

[0020] S2, alignment stage: based on the PID control algorithm and path planning formula, the robot is moved to the position of the produced injection molded part, and the injection molded part is inserted into the part slot;

[0021] S3, automatic part removal stage: the negative pressure mechanism works, and the negative pressure device forms negative pressure in the negative pressure chamber. When through hole 1 and through hole 2 are connected, the negative pressure absorbs the injection molded part and fits it into the part groove. Finally, the moving manipulator places the injection molded part in the desired position.

[0022] As a preferred embodiment of the above technical solution, the PID control algorithm formula is:

[0023]

[0024] Where u(t) is the control output, i.e., the output signal of the controller at time t, which is used to adjust the control amount of the robot or system behavior; K p is the proportional gain; e(t) is the current error, defined as the difference between the target value and the actual value; K i It is the integral gain, which is used to eliminate the steady-state error. It accumulates past errors to adjust the control output to ensure that the system eventually reaches the target value. is the integral term, which represents the accumulation of errors from time 0 to the current time t. The system adjusts the persistent errors. K d is the derivative gain, which is used to predict future error changes. It adjusts the control output based on the rate of change of the current error; It is a differential term, which indicates the rate of change of the current error with respect to time.

[0025] As a preferred embodiment of the above technical solution, the path planning formula is:

[0026] nn

[0027] B(t)=(1-t)P0+nt(1-t)P1+...+t n P n ;

[0028] Among them, B(t) represents the position of the path point calculated under parameter t, and this point is on the motion trajectory of the robot; t is a parameter, and the range is usually [0,1]. When t = 0, B(0) corresponds to the starting point; when t = 1, B(1) corresponds to the ending point. By changing t, it is used to obtain different points on the path; n is the order of the Bezier curve, which determines the number of control points of the curve. A Bezier curve of order n has n+1 control points; P0 is the starting control point; P1 is the intermediate control point; P n The ending control point.

[0029] The beneficial effects of the present invention are:

[0030] 1. Compared with the traditional method of "clamping the injection molded part to take out the part", the negative pressure automatic taking out of the present invention will not apply excessive pressure to the injection molded part, thereby effectively reducing the damage to the injection molded part; at the same time, the second through hole in the present invention includes a part located in the part groove and a part located outside the part groove, wherein the second through hole located in the part groove can provide gas negative pressure, so that the injection molded part fits and is adsorbed in the part groove, and the second through hole located outside the part groove can also provide negative pressure airflow to extract the heat dissipated by the injection molded part, thereby playing a good auxiliary heat dissipation role for the injection molded part;

[0031] 2. In the robot picking stroke control method of the present invention, the control performance can be optimized according to the system requirements based on the PID control algorithm to ensure the accuracy and stability of the robot when performing tasks; the path planning based on the Bezier curve can effectively control the movement trajectory of the robot in the picking process to ensure the accuracy and smoothness of the operation; by adjusting the position of the control point, the picking path can be optimized according to the specific application requirements, making the path smoother and reducing the probability of the injection molded parts falling out of the slot. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The figure shows a front perspective structural diagram of the automatic injection molded part removal robot in Example 1;

[0033] Figure 2 The figure shows a schematic diagram of the back three-dimensional structure of the automatic take-out robot for injection molded parts in Example 1;

[0034] Figure 3 The figure shows a schematic diagram of the three-dimensional structure of the suction seat in the automatic taking-out robot for injection molded parts in Example 1;

[0035] Figure 4 Shown is a cross-sectional view of the internal structure of the base in the automatic injection molded part removal robot in Example 1.

[0036] In the figure: 10, base; 11, foundation pit; 12, installation groove; 13, negative pressure chamber; 14, through hole one; 20, suction seat; 21, slot; 22, fixing part; 221, 23, bolt; 31, through hole two; 33, three-way pipe; 34, connecting pipe; 35, solenoid valve; 40, mechanical arm; 50, angle adjustment mechanism; 51, fixing plate; 52, column; 53, adapter; 54, motor; 55, rotating shaft; 56, gear disc one; 57, gear disc two. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments.

[0038] Example

[0039] like Figure 1 , Figure 2 As shown, the automatic take-up robot for injection molded parts comprises a base 10, a suction seat 20 is embedded in the front of the base 10, a slot 21 adapted to the injection molded parts is provided on the front of the suction seat 20, and an angle adjustment mechanism 50 is provided on the back of the base 10;

[0040] The manipulator also includes a negative pressure mechanism, which includes a negative pressure chamber 13 opened inside the base 10 and a through hole 14 connected thereto, the negative pressure chamber 13 is connected to an external negative pressure device, and a through hole 2 31 corresponding to the through hole 14 is opened on the suction seat 20;

[0041] Before working, the manipulator of the present invention selects a suction seat 20 that is compatible with the injection molded part, and installs the back side of the suction seat 20 in an embedded manner in the foundation pit 11 on the front side of the base 10. During installation, the fixing part 22 is aligned with the installation groove 12 and is threadedly fixed by bolts 23; then the manipulator is moved to the position of the produced injection molded part, and the injection molded part is inserted into the part groove 21, and then the negative pressure mechanism works, and the negative pressure device causes the negative pressure chamber 13 to form a negative pressure. Under the connection between the through hole 14 and the through hole 2 31, the negative pressure absorbs the injection molded part and makes it fit the part groove 21, and finally the manipulator is moved to place the injection molded part in the desired position. Compared with the traditional method of "clamping the injection molded parts to pick up the parts", the negative pressure automatic picking up of the present invention will not apply excessive pressure to the injection molded parts, thereby effectively reducing the damage to the injection molded parts; at the same time, the second through hole 31 in the present invention includes a part located in the part groove 21 and a part located outside the part groove 21, wherein the second through hole 31 located in the part groove 21 can provide gas negative pressure, so that the injection molded parts are fitted and adsorbed in the part groove 21, and the second through hole 31 located outside the part groove 21 can also provide negative pressure airflow to extract the heat dissipated by the injection molded parts, thereby playing a good auxiliary heat dissipation role for the injection molded parts.

[0042] A foundation pit 11 is provided on the front of the base 10, and the foundation pit 11 is adapted to the suction seat 20. It should be noted that different suction seats 20 have the same external shape and are adapted to the foundation pit 11, and only the slots 21 are different and adapted to different injection molded parts; thus, the robot arm of the present invention can be adapted to different injection molded parts, and has wider adaptability.

[0043] like Figure 3 As shown, a fixing portion 22 is integrally fixedly connected to the suction seat 20 , and a mounting groove 12 matched with the fixing portion 22 is provided on the front of the base 10 , and the fixing portion 22 is fixedly installed on the mounting groove 12 by bolts 23 .

[0044] like Figure 1 , Figure 4As shown, a three-way pipe 33 is installed on the outer wall of the base 10, one end of the three-way pipe 33 is connected to the negative pressure chamber 13, and the other two ends of the three-way pipe 33 are respectively installed with a connecting pipe 34 and a solenoid valve 35. In this embodiment, the connecting pipe 34 is connected to an external vacuum pump. When the negative pressure is taken out, the solenoid valve 35 is closed, and the vacuum pump works to extract the internal gas of the negative pressure chamber 13 to form a negative pressure inside, thereby forming a negative pressure in the through hole 1 14 and the through hole 2 31, thereby realizing the automatic negative pressure taking out; when unloading, the vacuum pump is closed, and the solenoid valve 35 is opened to balance the internal air pressure of the negative pressure chamber 13, the through hole 1 14, and the through hole 2 31, thereby realizing the unloading of the injection molded parts.

[0045] The angle adjustment mechanism 50 includes a fixing plate 51 fixedly connected to the back of the base 10, a column 52 fixedly connected to the other side of the fixing plate 51, and an adapter 53 is provided on both ends of the column 52 for rotation, and a driving assembly is provided on the adapter 53. The driving assembly includes a motor 54 fixedly installed on the adapter 53, the output shaft of the motor 54 is fixedly connected to a rotating shaft 55, the other end of the rotating shaft 55 is fixedly connected to a toothed disc 1 56, and one end of the column 52 is fixedly connected to a toothed disc 2 57, and the toothed disc 2 57 and the toothed disc 1 56 are meshed for transmission.

[0046] The angle adjustment mechanism 50 is used to adjust the offset angle of the base 10, so as to facilitate the base 10 and the front side of the suction seat 20 to better fit the injection molded part; the working principle of the angle adjustment mechanism 50 is: the motor 54 drives the rotating shaft 55 to rotate, and the rotation of the rotating shaft 55 drives the column rod 52 and the fixed plate 51 to rotate under the meshing transmission of the gear plate 1 56 and the gear plate 2 57, thereby playing the role of adjusting the offset angle of the base 10.

[0047] The robotic arm 40 is fixedly connected to a side of the adapter 53 away from the base 10 .

[0048] A method for controlling a pickup stroke is provided. The method for controlling a pickup stroke is applied to the above-mentioned automatic pickup robot for injection molded parts. The method for controlling a pickup stroke comprises the following steps:

[0049] S1, pre-assembly stage: select a suction seat 20 that matches the injection molded part, and install the suction seat 20 in an embedded manner on the back side of the foundation pit 11 on the front side of the base 10. During installation, the fixing part 22 is aligned with the installation groove 12 and is threadedly fixed by bolts 23;

[0050] S2, alignment stage: based on the PID control algorithm and the path planning formula, the robot is moved to the position of the produced injection molded part, and the injection molded part is inserted into the part slot 21;

[0051] S3, automatic picking stage: the negative pressure mechanism works, and the negative pressure device forms negative pressure in the negative pressure chamber 13. When the through hole 14 and the through hole 2 31 are connected, the negative pressure absorbs the injection molded part and makes it fit the part groove 21. Finally, the moving manipulator places the injection molded part in the desired position.

[0052] The PID control algorithm formula is:

[0053]

[0054] Where u(t) is the control output, i.e., the output signal of the controller at time t, which is used to adjust the control amount of the robot or system behavior; K p is the proportional gain; e(t) is the current error, defined as the difference between the target value and the actual value; K i It is the integral gain, which is used to eliminate the steady-state error. It accumulates past errors to adjust the control output to ensure that the system eventually reaches the target value. is the integral term, which represents the accumulation of errors from time 0 to the current time t. The system adjusts the persistent errors. K d is the derivative gain, which is used to predict future error changes. It adjusts the control output based on the rate of change of the current error; It is a differential term, which indicates the rate of change of the current error with respect to time.

[0055] The PID control algorithm provides an effective control strategy by combining the three control methods of proportional, integral and differential. The adjustment of each parameter can optimize the control performance according to the needs of the system and ensure the accuracy and stability of the manipulator when performing tasks.

[0056] The path planning formula is:

[0057] nn

[0058] B(t)=(1-t)P0+nt(1-t)P1+...+t n P n ;

[0059] Among them, B(t) represents the position of the path point calculated under parameter t, and this point is on the motion trajectory of the robot; t is a parameter, and the range is usually [0,1]. When t = 0, B(0) corresponds to the starting point; when t = 1, B(1) corresponds to the ending point. By changing t, it is used to obtain different points on the path; n is the order of the Bezier curve, which determines the number of control points of the curve. A Bezier curve of order n has n+1 control points; P0 is the starting control point; P1 is the intermediate control point; P n The ending control point.

[0060] In the robot picking stroke control method, the path planning of the Bezier curve can effectively control the motion trajectory of the robot during the picking process, ensuring the accuracy and smoothness of the operation. By adjusting the position of the control point, the picking path can be optimized according to specific application requirements, making the path smoother and reducing the probability of the injection molded part falling from the part slot 21.

[0061] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them.

Claims

1. Automatic injection molded parts removal robot, characterized in that: The invention comprises a base (10), a suction seat (20) is embedded in the front of the base (10), a slot (21) adapted to the injection molded part is provided on the front of the suction seat (20), and an angle adjustment mechanism (50) is provided on the back of the base (10); The manipulator further comprises a negative pressure mechanism, wherein the negative pressure mechanism comprises a negative pressure chamber (13) opened inside the base (10) and a through hole (14) connected thereto, the negative pressure chamber (13) is connected to an external negative pressure device, and a through hole (31) corresponding one-to-one to the through hole (14) is opened on the suction seat (20); The front side of the suction seat (20) is aligned with the injection molded part and embeds it into the part groove (21); the negative pressure device forms a negative pressure in the negative pressure chamber (13); and when the through hole 1 (14) and the through hole 2 (31) are connected, the negative pressure sucks the injection molded part and makes it fit into the part groove (21).

2. The automatic injection molded parts removal robot according to claim 1, characterized in that: A foundation pit (11) is provided on the front side of the base (10), and the foundation pit (11) and the suction piece seat (20) are matched.

3. The automatic take-out robot for injection molded parts according to claim 1, characterized in that: A fixing portion (22) is integrally fixedly connected to the suction seat (20), a mounting groove (12) matching the fixing portion (22) is provided on the front side of the base (10), and the fixing portion (22) is fixedly mounted on the mounting groove (12) by means of bolts (23).

4. The automatic injection molded parts removal robot according to claim 1, characterized in that: A three-way pipe (33) is installed on the outer wall of the base (10), one end of the three-way pipe (33) is connected to the negative pressure chamber (13), and the other two ends of the three-way pipe (33) are respectively installed with a connecting pipe (34) and a solenoid valve (35).

5. The automatic injection molded parts removal robot according to claim 1, characterized in that: The angle adjustment mechanism (50) comprises a fixing plate (51) fixedly connected to the back side of the base (10), a column (52) fixedly connected to the other side of the fixing plate (51), an adapter seat (53) being rotatably sleeved at both ends of the column seat (52), and a driving assembly being arranged on the adapter seat (53).

6. The automatic take-out robot for injection molded parts according to claim 5, characterized in that: A side of the adapter (53) away from the base (10) is fixedly connected to a mechanical arm (40).

7. The automatic take-out robot for injection molded parts according to claim 5, characterized in that: The driving assembly comprises a motor (54) fixedly mounted on an adapter (53), the output shaft of the motor (54) being fixedly connected to a rotating shaft (55), the other end of the rotating shaft (55) being fixedly connected to a toothed disc 1 (56), one end of the column rod (52) being fixedly connected to a toothed disc 2 (57), and the toothed disc 2 (57) and the toothed disc 1 (56) being meshed for transmission.

8. A method for controlling a pickup stroke, characterized in that: The picking stroke control method is applied to the automatic picking robot for injection molded parts described in any one of claims 1 to 7, and the picking stroke control method comprises the following steps: S1, pre-assembly stage: select a suction seat (20) that matches the injection molded part, and install the suction seat (20) in an embedded manner on the back side in the foundation pit (11) on the front side of the base (10). During installation, the fixing part (22) is aligned with the installation groove (12) and is threadedly fixed by bolts (23); S2, alignment stage: based on the PID control algorithm and the path planning formula, the robot arm is moved to the position of the produced injection molded part, and the injection molded part is inserted into the part slot (21); S3, automatic part removal stage: the negative pressure mechanism works, and the negative pressure device forms a negative pressure in the negative pressure chamber (13). When the through hole 1 (14) and the through hole 2 (31) are connected, the negative pressure absorbs the injection molded part and makes it fit into the part groove (21). Finally, the moving manipulator places the injection molded part in the desired position.

9. A method for controlling the pickup stroke according to claim 8, characterized in that: The PID control algorithm formula is: Where u(t) is the control output, i.e., the output signal of the controller at time t, which is used to adjust the control amount of the robot or system behavior; K p is the proportional gain; e(t) is the current error, defined as the difference between the target value and the actual value; K i It is the integral gain, which is used to eliminate the steady-state error. It accumulates past errors to adjust the control output to ensure that the system eventually reaches the target value. is the integral term, which represents the accumulation of errors from time 0 to the current time t. The system adjusts the persistent errors. K d is the derivative gain, which is used to predict future error changes. It adjusts the control output based on the rate of change of the current error; It is a differential term, which indicates the rate of change of the current error with respect to time.

10. A method for controlling a pickup stroke according to claim 8, characterized in that: The path planning formula is: B(t)=(1-t) n P0+nt(1—t) n P1+...+t n P n ; Among them, B(t) represents the position of the path point calculated under parameter t, and this point is on the motion trajectory of the robot; t is a parameter, and the range is usually [0,1]. When t = 0, B(0) corresponds to the starting point; when t = 1, B(1) corresponds to the ending point. By changing t, it is used to obtain different points on the path; n is the order of the Bezier curve, which determines the number of control points of the curve. A Bezier curve of order n has n+1 control points; P0 is the starting control point; P1 is the intermediate control point; P n The ending control point.

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