Rapid automatic tool changing device for mechanical arm

Abstract

The invention discloses a mechanical arm rapid automatic tool changing device which comprises a tool chuck, a tool releasing frame, a tool magazine, a pneumatic clamping jaw and a lifting air cylinder, the tool chuck is used for clamping and releasing a tool, and the tool releasing frame is used for extruding the tool chuck to open the tool chuck, so that the tool is in a movable state; the tool chuck and the tool release frame on the locking module press each other, so that the tool chuck is opened, the pneumatic clamping jaw is used for clamping the tool, and then the lifting air cylinder is used for placing the tool into the corresponding tool magazine. And then the pneumatic clamping jaw and the lifting air cylinder are used for moving the tool to the opened tool chuck in reverse, the tool is successfully installed, automatic tool changing of the tool is achieved, and the defects that manual tool changing is unsafe and the tool changing efficiency is low are overcome. The automatic tool changing device is easy to operate, the whole clamping step is high in automation degree, the structure is simple, and the tool changing efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of tool changing, and in particular relates to a rapid and automatic tool changing device for a mechanical arm. Background Art

[0002] Traditional tool changing devices generally use fixed rotary hydraulic devices. This type of tool changing device has a slow speed, a long tool changing time, and a large footprint, which limits the freedom and workspace of the robot arm processing. In addition, traditional tool changing technology has the disadvantages of high cost, long cycle, low safety, and cannot meet the existing robot arm composite processing requirements. If the tool is changed manually, a series of problems will arise, such as small tool changing space, poor tool changing environment, and low tool changing efficiency. Robot arm tool changing technology can ensure a smooth tool changing process in different tasks.

[0003] Quickly and accurately change the tool, avoid manual tool change, reduce the waste of non-processing time, and achieve high-efficiency and automated production. Therefore, the application of robot tool change technology is becoming more and more extensive. But at the same time, the requirements for the accuracy and reliability of the robot arm are getting higher and higher, and its corresponding structure is becoming more and more complex.

[0004] Compared with other automatic tool changing devices for robot arms, the present invention has a simpler structure, lower manufacturing cost, and lower precision requirements for the robot arm. The present invention is designed based on the principle of manual tool changing, and can quickly realize the disassembly and assembly of the tool, avoid manual tool changing, and improve processing efficiency. Summary of the invention

[0005] The purpose of the present invention is to provide a robot arm fast automatic tool changing device to solve the above-mentioned problems.

[0006] To achieve the above object, the present invention provides the following technical solutions: a mechanical arm fast automatic tool changing device, comprising a tool chuck, a tool stripping rack, a tool magazine, a pneumatic clamp and a lifting cylinder, wherein the tool chuck is used to clamp and release the tool, and the tool stripping rack is used to press the tool chuck against each other, thereby opening the tool chuck and making the tool movable;

[0007] The pneumatic clamp is used to clamp the tool, and cooperates with the lifting cylinder to realize the separation and combination of the tool and the tool chuck;

[0008] The tool chuck is composed of a mechanical arm adapter end, a clamping spring, a clamping block, a tool chuck housing, a steel ball, a fixing ring, a reset spring, and a steel ball holder. The mechanical arm transports the tool chuck to the top of the tool stripper rack. The tool chuck housing contacts the upper surface of the U-shaped groove of the tool stripper rack and generates an extrusion force that compresses the reset spring. The steel ball is arranged in a conical hole on the circumference of the steel ball holder and can move freely. The tool chuck can adjust the clamping force by increasing or decreasing the thickness of the adjustment gasket between the clamping spring and the clamping block.

[0009] Preferably, the tool stripper allows the tool to enter its U-shaped groove, and the tool chuck shell rests on the U-shaped groove of the tool stripper. A magnet is embedded in the tool chuck, and the magnet is used to generate attraction for the tool so that the tool will not fall. The pneumatic clamp located at the bottom of the tool clamps the tool, and the tool is driven by the descent of the lifting cylinder to separate from the tool chuck. There are 4 tool strippers, corresponding to 4 different types of tool holes in the tool magazine.

[0010] Preferably, the tool magazine has a total of 4 tool holes arranged side by side, each of which is used to install different types of tools.

[0011] Preferably, when the pneumatic clamp clamps the tool to be disassembled, the lifting cylinder drives the clamp and the tool to move downward, and transports the tool from the tool joint to the tool hole of the tool magazine to complete the removal of the tool. When the pneumatic clamp clamps the tool to be installed, the lifting cylinder drives the pneumatic clamp and the tool to move upward, and transports the tool from the tool magazine into the tool chuck to complete the installation of the tool.

[0012] Preferably, the lifting cylinder is loaded with 4 pneumatic grippers, and the two work together to complete the disassembly and installation of the tool. The entire action process is controlled by PLC. The PLC sends signals to control the opening and closing of the pneumatic gripper relay and the lifting cylinder intermediate relay, and the two relays control the opening and closing of the lifting cylinder and the pneumatic gripper respectively.

[0013] Preferably, the mechanical arm drives the end locking module to move to position the tool hole and lift the locking module, and cooperates with the automatic tool changing device to realize automatic tool changing.

[0014] Preferably, the pneumatic clamp and the lifting cylinder are connected by a clamping cylinder base plate, and the clamping cylinder base plate and the lifting cylinder are connected by long bolts, so that the pneumatic clamp, the clamping cylinder base plate and the lifting cylinder work as a whole, the tool magazine and the lifting cylinder base are connected by double-headed studs, and the lifting cylinder base and the tool stripping rack base are connected by long threads, so that the tool magazine, the lifting cylinder base and the tool stripping rack base are a whole.

[0015] Technical effects and advantages of the present invention: Compared with the common tool changing device, the present invention opens the tool chuck by pressing the tool chuck and the tool stripper on the locking module, clamps the tool with the pneumatic clamp, and then places the tool into the corresponding tool library with the lifting cylinder. In turn, the pneumatic clamp and the lifting cylinder are used to move the tool to the opened tool chuck, and the tool is successfully installed, realizing automatic tool changing, overcoming the shortcomings of unsafe manual tool changing and low tool changing efficiency. The automatic tool changing device is easy to operate, the entire clamping step has a high degree of automation, and the structure is simple, which improves the tool changing efficiency and reduces the production cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The overall structure diagram of the automatic tool changing device of the present invention;

[0017] Figure 2 A full cross-sectional view of the tool chuck of the present invention showing the tool in a loosened and clamped state respectively;

[0018] Figure 3 The cylinder and gripper control circuit diagram of the present invention;

[0019] Figure 4 The PLC control module interface of the present invention;

[0020] Figure 5 The robot arm control module interface of the present invention;

[0021] Figure 6 An exploded view of the automatic tool changing device of the present invention;

[0022] Figure 7 Schematic diagram of the pneumatic clamp of the present invention clamping a tool;

[0023] Figure 8 Schematic diagram of the lifting cylinder of the present invention sending the tool into the tool library;

[0024] Fig. 9 Schematic diagram of the pneumatic clamping jaws and lifting cylinder of the present invention sending the tool into the tool chuck. DETAILED DESCRIPTION

[0025] 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.

[0026] The present invention provides Figure 1-Figure 9 A robot arm fast automatic tool changing device as shown in Figure 1As shown, it includes five parts, namely, a tool stripping frame 3, a tool magazine 8, a pneumatic clamp 2, a lifting cylinder 1, and a tool chuck 5. The tool stripping frame 3 is used to open the tool chuck 5, so that the tool 4 and the tool chuck 5 can be separated and combined; the tool magazine 8 is used to place four different tools 4; the pneumatic clamp 2 is used to clamp the tool 4, and cooperates with the lifting cylinder 1 to realize the separation and combination of the tool 4 and the tool chuck 5; the lifting cylinder 1 is used to move the tool 4 and the pneumatic clamp 2 back and forth from the tool chuck 5 to the tool magazine 8 to complete the removal and installation of the tool.

[0027] like Figure 2 As shown in (a), at this time, the tool chuck 5 is in a loosened state. The tool chuck consists of the following parts. The robot arm adapter end 2.1, the steel ball holder 2.2, the reset spring 2.3, the fixing ring 2.4, the steel ball 2.7, the tool chuck housing 2.8, the clamping block 2.9, and the clamping spring 2.10. When the robot arm 7 sends the tool chuck 5 to the top of the U-shaped groove 2.6 of the tool stripping rack, the tool chuck housing 2.8 and the U-shaped groove 2.6 of the tool stripping rack are squeezed against each other. The tool chuck housing 2.8 is subjected to an upward squeezing force from the U-shaped groove 2.6 of the tool stripping rack, so that the reset spring 2.3 is squeezed. The tool chuck housing 2.8 does not squeeze the steel ball 2.7 inward, and the steel ball 2.7 can move freely in the conical hole on the circumference of the steel ball holder 2.2. The tool 4 can move freely in the radial direction in the inner hole of the steel ball holder 2.2. The tool chuck 5 is in a loosened state and can change tools freely;

[0028] The mechanical arm adapter end 2.1 is connected to the steel ball holder 2.2 by interference connection, and the two sides of the clamping spring 2.10 are in direct contact with the mechanical arm adapter end 2.1 and the clamping block 2.9. The clamping block 2.9 is located on the steel ball holder 2.2. The tool chuck housing 2.8 is sleeved on the outside of the steel ball holder 2.2 and the reset spring 2.3, and is clearance-matched with the steel ball holder 2.2. The upper and lower surfaces of the reset spring 2.3 are in contact with the steel ball holder 2.2 and the tool chuck housing 2.8. When the tool chuck is in the loose state, the steel ball 2.7 can move freely in the tapered hole on the circumference of the steel ball holder 2.2. When the tool chuck is in the clamping state, the steel ball 2.7 is squeezed by the tool chuck housing 2.8, is restricted in the tapered hole of the steel ball holder 2.2 and is in direct contact with the groove of the tool 4, and together with the steel ball holder 2.2, completes the locking of the tool.

[0029] like Figure 2(b) shows that the tool chuck 5 is in a clamped state. When the tool chuck 5 leaves the tool stripper 3 and there is no external force acting on the tool chuck housing 2.8, the reset spring 2.3 pushes the tool chuck housing 2.8 toward the fixing ring 2.4, and the steel ball 2.7 is squeezed by the tool chuck housing 2.8 and confined in the tapered hole. At this time, the tool 4 in the inner hole of the steel ball holder 2.2 is positioned by the inner hole of the steel ball holder 2.2 and the steel ball 2.7, and the clamping force is provided by the clamping block 2.9. At this time, the tool chuck 5 is in a locked state. The tool chuck 5 adjusts the clamping force by increasing or decreasing the thickness of the gasket between the clamping spring 2.10 and the clamping block 2.9.

[0030] like Figure 3 As shown in the figure, the main control lines are the control gas line and signal line of the cylinder. The two gas lines for controlling opening and closing are connected to the cylinder, and the signal line is connected to the PLC. The PLC sends signals to control the opening and closing of the pneumatic gripper relay and the intermediate relay of the lifting cylinder, and the relay controls the opening and closing of the lifting cylinder and the pneumatic gripper respectively. The air compressor compresses the gas to provide power, and the oil-water separator is used to remove moisture and impurities in the compressed air to protect the solenoid valve and other pneumatic equipment from moisture and impurities. Figure 4 This is a schematic diagram of the PLC control module.

[0031] like Figure 5 As shown, the robot arm control module is as follows. The robot arm is mainly responsible for moving to the tool change point to squeeze the tool chuck and the tool stripper frame to open the tool chuck and is responsible for the lifting and lowering of the locking module. The control part of the tool change process is as follows:

[0032] The specific control process of tool disassembly is as follows: by inputting the program, the robot arm moves the tool to be replaced to the tool change point where the tool hole indicator light is green, and squeezes the tool chuck and the tool stripper so that the tool chuck is in an open state; the PLC control module sends a signal to control the opening and closing of the lifting cylinder relay, and the lifting cylinder relay controls the reversing of the lifting cylinder solenoid valve, so that the lifting cylinder rises to a fixed position, and then the PLC control module sends a signal to control the opening and closing of the pneumatic gripper relay, and the pneumatic gripper relay controls the reversing of the gripper solenoid valve, so that the pneumatic gripper clamps the tool; the PLC control module sends a signal to control the opening and closing of the lifting cylinder relay, and the lifting cylinder relay controls the reversing of the lifting cylinder solenoid valve, so that the lifting cylinder descends to a fixed position to send the tool to the corresponding tool hole, and the tool hole indicator light turns red, and then the PLC control module sends a signal to control the opening and closing of the pneumatic gripper relay, and the pneumatic gripper relay controls the reversing of the pneumatic gripper solenoid valve, so that the pneumatic gripper releases the tool.

[0033] The specific control process of installing the tool is as follows: by inputting the program, the robotic arm moves to the tool change point above the tool hole to be installed where the tool library status displays a green light, so that the tool chuck is squeezed against the tool stripper to open the tool chuck; the PLC control module sends a signal to control the opening and closing of the pneumatic gripper relay, and the gripper relay controls the reversal of the gripper solenoid valve, so that the pneumatic gripper clamps the tool to be installed, and then the PLC control module sends a signal to control the opening and closing of the lifting cylinder relay, and the lifting cylinder relay controls the reversal of the cylinder solenoid valve, thereby causing the lifting cylinder to rise and send the tool to be installed to the tool chuck; after the tool is installed, the PLC control module sends a signal to control the opening and closing of the pneumatic gripper relay, and the gripper relay controls the reversal of the gripper solenoid valve, so that the pneumatic gripper releases the tool to be installed, and then the PLC control module sends a signal to control the opening and closing of the lifting cylinder relay, and the lifting cylinder relay controls the reversal of the cylinder solenoid valve, thereby causing the lifting cylinder to descend to its original position; the robotic arm leaves the tool change area and returns to the working area.

[0034] like Figure 6 The figure shows an exploded view of the automatic tool changing device. The tool magazine 8 is connected to the lifting cylinder base 3.2 by a stud 3.3; the stripping tool holder base 3.11 is connected to the lifting cylinder base 3.2 by an M12 long hexagonal bolt 3.10, so that the tool magazine 8, the lifting cylinder base 3.2 and the stripping tool holder base 3.11 become a whole. The clamping cylinder base plate 3.7 and the pneumatic clamp 2 are connected by an M3 hexagonal bolt 3.6; the clamping cylinder base plate 3.7 and the lifting cylinder piston 3.1 are connected by an M10 hexagonal bolt 3.6 and an M10 hexagonal nut 3.4, so that the lifting cylinder piston 3.1, the clamping cylinder base plate 3.7 and the pneumatic clamp 2 become a whole. The cross section of the bottom surface of the stripping tool holder 3 is a square, so it is inserted into the square hole of the stripping tool holder base 3.11 for fixing.

[0035] Based on the above structural scheme, the main clamping principle of the automatic tool changing device in this example is:

[0036] like Figure 2As shown in (a), the robot arm 7 sends the tool 4 into the corresponding U-shaped groove 2.6 of the tool stripping rack. Since the diameter of the tool chuck shell 2.8 is larger than the width of the U-shaped groove 2.6 of the tool stripping rack, and the diameter of the tool 4 is smaller than the width of the U-shaped groove 2.6 of the tool stripping rack, the tool 4 can enter the U-shaped groove 2.6 of the tool stripping rack, and the tool chuck 5 contacts the upper surface of the U-shaped groove 2.6 of the tool stripping rack. The robot arm 7 presses the tool chuck 5 against the upper surface of the U-shaped groove 2.6 of the tool stripping rack, so that the tool chuck shell 2.8 of the tool chuck 5 is lifted up, the reset spring 2.3 is compressed, and the tool chuck shell 2.8 does not squeeze the steel ball 2.7 inward. The steel ball 2.7 can move freely in the tapered hole on the circumference of the steel ball holder 2.2, so that the tool chuck 5 is opened. Since the tool chuck 5 has a magnet embedded in it, it has a smaller attraction to the tool 4, so the tool 4 will not fall immediately. Figure 8 As shown, when the tool chuck 5 is opened, the pneumatic clamp 2 begins to clamp the end of the tool 4. After the pneumatic clamp 2 clamps the tool 4, the lifting cylinder 1 descends and puts the tool 4 into the corresponding tool magazine 8. This process is the process of sending the tool to be disassembled to the tool magazine.

[0037] like Figure 2 As shown in (a), the robot arm 7 moves the tool chuck 5 to the position of the tool magazine 8 to be replaced, so that the tool chuck housing 2.8 contacts the upper surface of the U-shaped groove 2.6 of the tool stripper, and the robot arm 7 presses the tool chuck 5 on the upper surface of the U-shaped groove 2.6 of the tool stripper, so that the tool chuck housing 2.8 is lifted up, the reset spring 2.3 is compressed, the tool chuck housing 2.8 does not squeeze the steel ball 2.7 inward, and the steel ball 2.7 can move freely in the tapered hole on the circumference of the steel ball holder 2.2, so that the tool chuck 5 is in an open state. Fig. 9 As shown, the pneumatic clamp 2 clamps the tool 4 to be replaced, and the lifting cylinder 1 sends the tool 4 to be replaced into the tool chuck 5. Since the tool chuck 5 has an embedded magnet, the tool 4 will not fall after the pneumatic clamp 2 is released. Figure 2 As shown in (b), when the robot arm 7 leaves the tool stripping frame 3, since there is no U-shaped groove 2.6 of the tool stripping frame to squeeze the tool chuck housing 2.8, the reset spring 2.3 pushes the tool chuck housing 2.8 toward the fixing ring 2.4, and the steel ball 2.7 is squeezed by the tool chuck housing 2.8 and is confined in the tapered hole. At this time, the tool 4 in the inner hole of the steel ball holder 2.2 is positioned by the inner hole and the steel ball 2.7, and the clamping force is provided by the clamping block 2.9. At this time, the tool 4 is in a clamped state, and the tool replacement is successful. The robot arm 7 leaves the tool changing area and enters the working area.

[0038] Based on the above principles, the specific automatic tool changing process includes the following steps:

[0039] Step 1: If Figure 2As shown in (a), the robot arm 7 sends the tool chuck 5 to the top of the U-shaped groove 2.6 of the tool stripping frame, and the tool chuck housing 2.8 in the tool chuck 5 is squeezed by the U-shaped groove 2.6 of the tool stripping frame and is lifted up, and the return spring 2.3 is compressed so that the tool chuck housing 2.8 no longer squeezes the steel ball 2.7 inwardly, and the steel ball 2.7 can move freely in the tapered hole on the circumference of the steel ball holder 2.2, so that the tool chuck 5 is in an open state. Since the tool chuck 5 has an embedded magnet, it has an attraction to the tool 4, so the tool 4 will not fall off;

[0040] Step 2: If Figure 8 As shown, the pneumatic clamp 2 clamps the tool 4, and the lifting cylinder 1 drives the pneumatic clamp 2 to move downward to send the tool 4 into the corresponding tool magazine 8, and then the pneumatic clamp releases the tool;

[0041] Step 3: The robot arm 7 moves to the top of the U-shaped groove 2.6 of the tool holder of the tool 4 to be replaced, and repeats step 1, so that the tool chuck 5 is in the open state;

[0042] Step 4: Fig. 9 As shown, the pneumatic clamp 2 clamps the tool 4 to be replaced; after the lifting cylinder 1 drives the pneumatic clamp 2 to send the tool 4 to be replaced into the tool chuck 5, the pneumatic clamp 2 releases the tool 4. Since the tool chuck 5 has a magnet embedded in it, it has an attraction to the tool 4, so the tool will not fall off;

[0043] Step 5: If Figure 2 As shown in (b), the robot arm 7 leaves the upper surface of the U-shaped groove 2.6 of the tool stripper. At this time, the tool chuck housing 2.8 will not be squeezed by the upper surface of the U-shaped groove 2.6 of the tool stripper. Under the action of the reset spring 2.3, the tool chuck housing 2.8 is pushed toward the fixing ring 2.4, and the steel ball 2.7 is squeezed by the tool chuck housing 2.8 and confined in the tapered hole. The clamping block 2.9 provides a clamping force to the tool 4, so that the tool 4 is in a clamped state and keeps the tool 4 stable. After the tool 4 is replaced, the robot arm 7 enters the working area and continues to work.

[0044] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A robot arm fast automatic tool changing device, characterized in that: It includes a tool chuck, a tool stripping rack, a tool magazine, a pneumatic clamp and a lifting cylinder. The tool chuck is used to clamp and release the tool. The tool stripping rack is used to press the tool chuck against each other, thereby opening the tool chuck and making the tool movable. The pneumatic clamp is used to clamp the tool, and cooperates with the lifting cylinder to realize the separation and combination of the tool and the tool chuck; The tool chuck is composed of a mechanical arm adapter end, a clamping spring, a clamping block, a tool chuck shell, a steel ball, a fixing ring, a reset spring, and a steel ball holder. The mechanical arm adapter end is connected to the steel ball holder by an interference connection. Both sides of the clamping spring are in direct contact with the mechanical arm adapter end and the clamping block. The clamping block is located on the steel ball holder. The tool chuck shell is sleeved on the outside of the steel ball holder and the reset spring, and is clearance-matched with the steel ball holder. The upper and lower surfaces of the reset spring are in contact with the steel ball holder and the tool chuck shell. The mechanical arm transports the tool chuck to the top of the tool stripping rack. The tool chuck shell is in contact with the upper surface of the U-shaped groove of the tool stripping rack and generates an extrusion force that compresses the reset spring. The steel ball is arranged in a conical hole on the circumference of the steel ball holder and can move freely. The tool chuck achieves adjustable clamping force by increasing or decreasing the thickness of the adjustment gasket between the clamping spring and the clamping block.

2. A robot arm fast automatic tool changing device according to claim 1, characterized in that: The tool stripper allows the tool to enter its U-shaped groove, and the tool chuck shell rests on the U-shaped groove of the tool stripper. A magnet is embedded in the tool chuck, and the magnet is used to generate attraction for the tool so that the tool will not fall. The pneumatic clamp located at the bottom of the tool clamps the tool, and the tool is driven by the descent of the lifting cylinder to separate from the tool chuck. There are 4 tool strippers, corresponding to 4 different types of tool holes in the tool library.

3. The robot arm fast automatic tool changing device according to claim 1, characterized in that: The tool magazine has a total of 4 tool holes arranged side by side, where different types of tools are installed respectively.

4. The robot arm fast automatic tool changing device according to claim 1, characterized in that: When the pneumatic clamp clamps the tool to be disassembled, the lifting cylinder drives the clamp and the tool to move downward, and transports the tool from the tool joint to the tool hole in the tool magazine to complete the removal of the tool. When the pneumatic clamp clamps the tool to be installed, the lifting cylinder drives the pneumatic clamp and the tool to move upward, and sends the tool from the tool magazine into the tool chuck to complete the installation of the tool.

5. The robot arm fast automatic tool changing device according to claim 1, characterized in that: The lifting cylinder is equipped with four pneumatic grippers, and the two work together to complete the removal and installation of the tool. The entire action process is controlled by PLC. The PLC sends signals to control the opening and closing of the pneumatic gripper relay and the lifting cylinder intermediate relay. The two relays control the opening and closing of the lifting cylinder and the pneumatic gripper respectively.

6. The robot arm fast automatic tool changing device according to claim 1, characterized in that: The mechanical arm drives the end locking module to move to position the tool hole and lift the locking module, and cooperates with the automatic tool changing device to realize automatic tool changing.

7. The robot arm fast automatic tool changing device according to claim 1, characterized in that: The pneumatic clamp and the lifting cylinder are connected by a clamping cylinder base plate, and the clamping cylinder base plate and the lifting cylinder are connected by long bolts, so that the pneumatic clamp, the clamping cylinder base plate and the lifting cylinder work as a whole. The tool magazine and the lifting cylinder base are connected by double-headed studs, and the lifting cylinder base and the tool stripping rack base are connected by long threads, so that the tool magazine, the lifting cylinder base and the tool stripping rack base are a whole.

Images