Bar self-adaptive clamping jaw based on lever force amplifier

Abstract

The utility model discloses a bar self-adaptive clamping jaw based on a lever force amplifier. The clamping jaw comprises a base, two acting air cylinders arranged front and back are installed above the base, the bottoms of the two acting air cylinders are connected with two rotating rods extending front and back through two levers respectively, the front ends of the two rotating rods are connected with two rotating clamping arms respectively, and V-shaped guide grooves are formed in the tail ends of the two rotating clamping arms respectively. Two outer clamping arms are further installed on the side face of the front end of the base, the two outer clamping arms are arranged on the outer sides of the two rotating clamping arms respectively, and the two outer clamping arms and the two rotating clamping arms form two clamping jaws respectively. According to the bar self-adaptive clamping jaw based on the lever reinforcement mechanism, a high-precision clamping jaw is replaced by a common air cylinder, the lever reinforcement mechanism and a V-shaped guide groove are designed, cost is reduced, the bar self-adaptive clamping jaw has high clamping force and repeated positioning precision, cutters of various sizes can be compatible, and the bar self-adaptive clamping jaw is suitable for various kinds of tools. And surface oil stains and large dimensional deviation can be resisted.

Description

Technical Field

[0001] This utility model relates to the field of industrial robots, and in particular to an adaptive gripper for bar stock based on a lever amplification mechanism. Background Technology

[0002] In the field of automated tool grinding machine retrofitting, the gripper device for robotic tool handling directly affects grinding accuracy and production line economy. Currently, over 90% of applications use standard two-finger pneumatic grippers (such as the SMC MHZ2 series), and their technical challenges are concentrated in three aspects:

[0003] 1. Insufficient clamping force: The standard jaw adopts a direct-push cylinder structure. Under the condition of 0.5MPa air source, the output clamping force is generally less than 120N. When clamping heavy tools with a diameter of more than 30mm, it is easy to slip, which will cause the tool to have an axial movement of 0.05-0.1mm during the grinding process.

[0004] 2. High cost: The purchase cost of high-precision grippers (repeat positioning accuracy ±0.01mm) is often as high as 6,000-8,000 yuan per set, accounting for more than 60% of the total cost of the pick-and-place mechanism, thus limiting the automation upgrade of small and medium-sized enterprises;

[0005] 3. Poor adaptability: The rigid contact method of traditional parallel grippers is prone to 2°-5° angular displacement when there is oil or debris on the tool surface, which can easily lead to failure of robot hand-eye calibration. Utility Model Content

[0006] To address the aforementioned issues, this invention provides a bar stock adaptive gripper based on a lever-driven force-increasing mechanism. It replaces the high-precision gripper with a conventional cylinder and incorporates a lever-driven force-increasing mechanism and a V-shaped guide groove design, thereby reducing costs. It offers high clamping force and repeatability, is compatible with various sizes of cutting tools, and can withstand surface oil contamination and significant dimensional deviations.

[0007] According to one aspect of this utility model, a bar stock adaptive gripper based on a lever-assisted force-multiplying mechanism is provided, comprising a base, two actuating cylinders arranged front to back mounted on the top of the base, two rotating rods extending front to back connected to the bottom of the two actuating cylinders respectively via two levers, and two rotating clamping arms connected to the front ends of the two rotating rods respectively, with V-shaped guide grooves provided at the ends of the two rotating clamping arms; two outer clamping arms are also mounted on the front side of the base, the two outer clamping arms are respectively disposed outside the two rotating clamping arms and form two grippers with the two rotating clamping arms respectively;

[0008] The lever includes an upper connecting block, a lower connecting frame, and a fulcrum rod. The top of the upper connecting block is connected to the actuating cylinder, the bottom of the lower connecting frame is connected to the rotating rod, and the bottom of the upper connecting block and the top of the lower connecting frame are movably connected through the fulcrum rod. The length ratio of the upper connecting block to the lower connecting frame is 1:3.5.

[0009] In some embodiments, the rear end of the base is connected to a mounting flange. This is advantageous because the base, or even the entire bar stock adaptive gripper, can be mounted on the robot via the mounting flange.

[0010] In some embodiments, two vertical side plates are respectively installed on the left and right sides of the base, and the two actuating cylinders are installed between the upper parts of the two side plates. The advantage is that a specific method for installing the two actuating cylinders on the base is described.

[0011] In some embodiments, the base has a through groove running vertically through the middle, and two through holes at both the front and rear ends. Both rotating rods are located within the through groove, with their front and rear ends passing through the respective through holes. The advantage is that it further describes the specific structure of the base.

[0012] In some embodiments, the V-groove has a 90° opening and is hard chrome plated. Its advantage lies in describing the specific structure of the V-groove, which, during use, contacts the tool to achieve automatic centering.

[0013] In some embodiments, cushioning pads are mounted on the rear sides of both rotating grippers. This is advantageous because the cushioning pads can elastically deform during clamping to accommodate surface foreign objects or dimensional fluctuations. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of a bar stock adaptive gripper based on a lever force amplification mechanism according to one embodiment of the present invention;

[0015] Figure 2 for Figure 1 The diagram shows the structure of the base.

[0016] Figure 3 for Figure 1 The diagram shows the structure after removing the base and side panels.

[0017] In the diagram: 1. Base; 2. Actuating cylinder; 3. Lever; 4. Rotating rod; 5. Rotating clamping arm; 6. Cutting tool; 11. Mounting flange; 12. Side plate; 13. Through groove; 14. Through hole; 31. Upper connecting block; 32. Lower connecting frame; 33. Pivot rod; 51. V-shaped guide groove; 52. Outer clamping arm. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings.

[0019] like Figure 1-3 As shown, the adaptive gripper for bar stock includes a base 1. One end of the base 1 (designated as the rear end, and the other end as the front end) is connected to a mounting flange 11, allowing it to be mounted on a robot via the mounting flange 11. Two vertical side plates 12 are mounted on both sides of the base 1 (referred to as the left and right sides). Two actuating cylinders 2, arranged front and rear, are mounted side-by-side between the upper parts of the two side plates. The actuating cylinders 2 are ordinary cylinders, with a unit price of less than 1000 yuan.

[0020] The two working cylinders 2 have a cylinder diameter of 32mm, a stroke of 50mm, and an air source pressure of 0.5~0.7MP. At the bottom of the two working cylinders 2, two rotating rods 4 extending forward and backward are connected by two levers 3 respectively, and two rotating clamping arms 5 are connected to the front end of the two rotating rods 4 respectively.

[0021] In addition, V-shaped guide grooves 51 are provided at the ends of both rotating clamping arms 5. The groove openings are 90° and their surfaces are plated with hard chrome with a plating thickness of 0.05cm and a hardness of HRC60 or higher. The V-shaped guide grooves 51 can use the principle of geometric self-centering to control the repeatability accuracy within ±0.015mm.

[0022] like Figure 2 As shown, the base 1 has a through groove 13 running vertically through the middle, and both rotating rods 4 are located in the through groove 13. The base 1 has two through holes 14 at both the front and rear ends, and the front and rear ends of the two rotating rods 4 pass through the through holes 14 respectively.

[0023] In addition, two outer clamping arms 52 are installed on the front side of the base 1. The two outer clamping arms 52 are respectively located on the outside of the two rotating clamping arms 5, and form two grippers with the two rotating clamping arms 5 respectively. That is, when the two rotating clamping arms 5 rotate, they can clamp the tool 6 with the adjacent outer clamping arms 52 respectively. The V-shaped guide groove 51 contacts the outer circular surface of the tool 6 to achieve automatic centering, and the opening and closing range of the grippers can smoothly accommodate tools 6 with a diameter of 3 to 16 mm.

[0024] Preferably, both rotating clamping arms 5 are fitted with buffer pads (not shown in the figure) made of polyurethane material with a Shore hardness of 80A on their rear sides. The buffer pads are 3mm thick and have a pre-compression of 0.5mm. The buffer pads are capable of elastic deformation during clamping to accommodate surface foreign objects or dimensional fluctuations.

[0025] like Figure 3As shown, lever 3 includes an upper connecting block 31, a lower connecting frame 32 and a fulcrum rod 33. The top of the upper connecting block 31 is connected to the piston rod of the actuating cylinder 2, the bottom of the lower connecting frame 32 is connected to the rotating rod 4, and the bottom of the upper connecting block 31 and the top of the lower connecting frame 32 are movably connected by the fulcrum rod 33.

[0026] The length ratio of the upper connecting block 31 to the lower connecting frame 32 is 1:3.5. For example, if the length of the upper connecting block 31 is 20mm, then the length of the lower connecting frame 32 is 70mm. That is, the ratio of the distance of the fulcrum rod 33 from the actuating cylinder 2 to its distance from the rotating rod 4 is 1:3.5, thus achieving a force amplification ratio of 1:3.5. Assuming the original clamping force is 120N, it can be increased to 420N through the lever 3.

[0027] The adaptive bar gripper based on a lever-assisted force-multiplying mechanism of this utility model has the following advantages:

[0028] 1. Lower cost: By using ordinary cylinders instead of high-precision grippers, the cost per set is reduced to less than 2,000 yuan, a cost reduction of 70%;

[0029] 2. High clamping force: Through the lever force amplification mechanism, the clamping force is 3.5 times that of traditional direct-push grippers;

[0030] 3. High repeatability: The V-shaped guide groove design enables a repeatability of ±0.015mm, meeting the requirements of precision grinding;

[0031] 4. High adaptability: Compatible with cutting tools with diameters of 3 to 16 mm, and can withstand surface oil stains and dimensional deviations of ±1.5 mm.

[0032] The above descriptions are merely some embodiments of this utility model. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of this utility model, and all such modifications and improvements fall within the protection scope of this utility model.

Claims

1. A bar stock adaptive gripper based on a lever-assisted force-multiplying mechanism, characterized in that: The system includes a base (1), on which two actuating cylinders (2) are mounted in a front-to-back configuration. The bottom of each of the two actuating cylinders (2) is connected to two rotating rods (4) extending in the front and back via two levers (3). Two rotating clamping arms (5) are connected to the front ends of the two rotating rods (4). V-shaped guide grooves (51) are provided at the ends of the two rotating clamping arms (5). Two outer clamping arms (52) are also mounted on the front side of the base (1). The two outer clamping arms (52) are respectively located on the outside of the two rotating clamping arms (5) and form two clamping claws with the two rotating clamping arms (5). The lever (3) includes an upper connecting block (31), a lower connecting frame (32), and a fulcrum rod (33). The top of the upper connecting block (31) is connected to the actuating cylinder (2), and the bottom of the lower connecting frame (32) is connected to the rotating rod (4). The bottom of the upper connecting block (31) and the top of the lower connecting frame (32) are movably connected through the fulcrum rod (33). The length ratio of the upper connecting block (31) and the lower connecting frame (32) is 1:3.

5.

2. The bar stock adaptive gripper based on a lever-assisted force-multiplying mechanism according to claim 1, characterized in that: The rear end of the base (1) is connected to a mounting flange (11).

3. The bar stock adaptive gripper based on a lever-assisted force-multiplying mechanism according to claim 1, characterized in that: Two vertical side plates (12) are installed on the left and right sides of the base (1), and two actuating cylinders (2) are installed between the upper parts of the two side plates (12).

4. The bar stock adaptive gripper based on a lever-assisted force-multiplying mechanism according to claim 1, characterized in that: The base (1) has a through groove (13) running vertically through the middle, and two through holes (14) at both the front and rear ends. The two rotating rods (4) are located in the through groove (13) and pass through each of the through holes (14) at their front and rear ends respectively.

5. The bar stock adaptive gripper based on a lever-assisted force-multiplying mechanism according to claim 1, characterized in that: The V-shaped guide groove (51) has a 90° opening and is plated with hard chrome.

6. The bar stock adaptive gripper based on a lever-assisted force-multiplying mechanism according to claim 1, characterized in that: Both of the rotating clamps (5) are fitted with buffer pads on their rear sides.

Images