A passive multifunctional mechanical gripper based on bistable mechanism

Abstract

The present invention discloses a passive multifunctional mechanical gripper based on a bistable mechanism, comprising a frame and a bistable mechanism and a reset mechanism arranged on the frame; the bistable mechanism comprises a clamping jaw, a tension spring and an elastic rope; the two clamping jaws are respectively mounted on opposite sides of the frame and rotate around a pin shaft, and L-shaped arms are respectively provided on the opposite surfaces of the two clamping jaws, and the two L-shaped arms are respectively connected to the two ends of the tension spring; the two ends of a plurality of elastic ropes are respectively connected to the peripheral sides of the two clamping jaws; when the two clamping jaws are not subjected to external force, they are in an open steady state, and the tension spring is used to maintain stability; when the two clamping jaws are subjected to external force, the tension spring gradually bends until the steady state switches, and the clamping jaws enter a closed steady state; the reset mechanism is used to apply a thrust to the two L-shaped arms to reset the two clamping jaws to the open state; during use, this solution does not require an external energy source to control the retraction and clamping of the two clamping jaws, thereby effectively solving the problem that the existing manipulator must rely on an active drive device for clamping operations.

Description

Technical Field

[0001] The present invention relates to the technical field of manipulators, and in particular to a passive multifunctional manipulator gripper based on a bistable mechanism. Background Art

[0002] At present, the basic research of robotics technology is becoming increasingly mature and is widely used in many fields such as aerospace, industrial production, and food processing. However, as a typical example in the field of robotics, there are still some unresolved problems with mechanical grippers. For example, the grasping action of mechanical grippers relies on the drive of electronic equipment such as motors. Due to unavoidable situations such as mechanical lubrication, such mechanical grippers may cause certain forms of pollution to the operating environment, restricting their widespread application in fields such as medicine and food processing. However, as a mainstream form of alternative to manual operation, the function of mechanical grippers on production lines is indispensable. Therefore, it is of great significance to propose a passive multifunctional mechanical gripper that does not rely on any drive device to meet the current challenges. Summary of the Invention

[0003] The object of the present invention is to provide a passive multifunctional mechanical gripper based on a bistable mechanism to solve the problem that existing mechanical grippers must rely on active drive devices for clamping operations.

[0004] In order to solve the above technical problems, the present invention provides a passive multifunctional mechanical gripper based on a bistable mechanism, comprising a frame and a bistable mechanism and a reset mechanism arranged on the frame; the bistable mechanism comprises a clamping jaw, a tension spring and an elastic rope; the two clamping jaws are respectively rotatably installed on the opposite sides of the frame, and L-shaped arms are provided on the opposite surfaces of the two clamping jaws, and the two L-shaped arms are respectively connected to the two ends of the tension spring, so that when the two clamping jaws are opened, the tension spring is placed in the space surrounded by the two L-shaped arms; there are multiple elastic ropes, and the two ends of the multiple elastic ropes are respectively connected to the circumferential sides of the two clamping jaws; when the two clamping jaws are not subjected to external force, the tension spring is used to maintain the open state of the two clamping jaws; when the two clamping jaws are subjected to external force, the tension spring is used to drive the clamping jaws to close, and the multiple elastic ropes are used to maintain the clamping process from offset; the reset mechanism is used to apply thrust to the two L-shaped arms to reset the two clamping jaws to the open state.

[0005] In one embodiment, a plurality of mounting through holes are provided on a side of the frame away from the bistable mechanism.

[0006] In one embodiment, both of the clamping jaws are provided with a strip groove, and the two strip grooves form an obtuse angle with the two clamping jaws respectively; the two opposite sides of the frame are provided with pins, and the two pins pass through the two strip grooves respectively, and the two pins are respectively the rotation axes of the two clamping jaws.

[0007] In one embodiment, the two L-shaped arms include a long arm segment and a short arm segment vertically connected to each other, the opposite surfaces of the two clamps are respectively connected to the long arm segments, the two short arm segments are respectively extended toward the opposite long arm segments, and the tension spring is connected between the two short arm segments.

[0008] In one embodiment, the reset mechanism includes a button, a push rod, a push plate and a pressure spring; the button and the bistable mechanism are respectively arranged on opposite sides of the frame; one end of the push rod is connected to the button, and the other end of the push rod passes through the frame and is connected to the push plate; the push plate is placed opposite to the two L-shaped arms; the pressure spring is sleeved outside the push rod, and the pressure spring is compressed between the button and the frame.

[0009] In one embodiment, the reset mechanism further includes a graphite guide rail, and the graphite guide rail is sleeved outside the push rod.

[0010] The beneficial effects of the present invention are as follows:

[0011] Since the two jaws are in the open steady state in the bistable state when no external force is applied, the tension spring is used to maintain the open state of the two jaws. Therefore, the two jaws can be controlled to move in the open state to the position where clamping is required. Moreover, since the tension spring gradually bends and stretches when the two jaws are subjected to external force, the steady-state switching mechanism will be triggered when the stretching exceeds a critical value, and the jaws enter the closed steady state in the bistable state. Since the steady-state switching process is time-consuming and has large deformation, the jaws can achieve rapid closing and grasping in this process. Therefore, by controlling the movement of the two jaws so that the jaws touch the object to be clamped, the two jaws will automatically close and clamp the object to be clamped. In this process, no external driving device is required as an energy source to control the closing and clamping of the two jaws, thereby effectively solving the problem that the existing manipulator must rely on an active driving device for clamping operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for use in the implementation. Obviously, the drawings described below are only some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0013] Figure 1 It is a structural diagram provided by an embodiment of the present invention;

[0014] Figure 2 yes Figure 1 Schematic diagram of the structure of the gripper in the closed state;

[0015] Figure 3 yes Figure 1 Schematic diagram of the amplified structure of the bistable mechanism;

[0016] Figure 4 yes Figure 2 Schematic diagram of the amplified structure of the bistable mechanism;

[0017] Figure 5 yes Figure 1 A schematic diagram of an enlarged structure of a reset mechanism;

[0018] Figure 6 It is a schematic structural diagram of the reset principle of the reset mechanism provided by an embodiment of the present invention.

[0019] The reference numerals are as follows:

[0020] 10. Frame; 11. Mounting hole; 12. Latch;

[0021] 20. Bistable mechanism; 21. Gripping jaw; 22. Tension spring; 23. Elastic rope; 24. L-shaped arm; 241. Long arm section; 242. Short arm section; 25. Strip groove;

[0022] 30. Reset mechanism; 31. Push button; 32. Push rod; 33. Push plate; 34. Pressure spring; 35. Graphite guide rail. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0024] The present invention provides a passive multifunctional mechanical gripper based on a bistable mechanism, which is implemented as follows: Figures 1 to 6As shown, the machine comprises a frame 10 and a bistable mechanism 20 and a reset mechanism 30 provided on the frame 10; the bistable mechanism 20 comprises a clamping jaw 21, a tension spring 22 and an elastic rope 23; the two clamping jaws 21 are respectively mounted on opposite sides of the frame 10 and rotate around the latch 12, and L-shaped arms 24 are provided on the opposite surfaces of the two clamping jaws 21, and the two L-shaped arms 24 are respectively connected to the two ends of the tension spring 22, so that when the two clamping jaws 21 are opened, the tension spring 22 is placed in the space surrounded by the two L-shaped arms 24; there are multiple elastic ropes 23, and the two ends of the multiple elastic ropes 23 are respectively connected to the peripheral sides of the two clamping jaws 21; when the two clamping jaws 21 are not subjected to external force, the two ends of the elastic ropes 23 are respectively connected to the peripheral sides of the two clamping jaws 21; When in use, the two jaws 21 are in the open steady state in the bistable state, and the tension spring 22 is used to maintain the open state of the two jaws 21; when the two jaws 21 are subjected to external force, the tension spring 22 gradually bends and stretches. When the elongation exceeds the critical value, the steady-state switching mechanism will be triggered, and the two jaws 21 will enter the closed steady state in the bistable state. Due to the characteristics of the stable-state switching process being short in time and large in deformation, the two jaws 21 can achieve rapid closing and grasping in this process, and the multiple elastic ropes 23 at this time are used to maintain the clamping process from offset; the reset mechanism 30 is used to apply thrust to the two L-shaped arms 24 to reset the two jaws 21 to the open state.

[0025] The passive multifunctional mechanical gripper mentioned above includes two stable states. The first one is Figure 1 and Figure 3 As shown, at this time, the tension spring 22 is clamped in the two L-shaped arms 24 in a stable state, so that the two clamping jaws 21 are in an open state; once the clamping jaws 21 are subjected to external forces, such as lateral thrust, vertical thrust, etc., Figure 2 and Figure 4 As shown, the tension spring 22 will be pulled by the clamping jaws and gradually bend and stretch. When the stretch exceeds a critical value, the steady-state switching mechanism will be triggered. At this time, the tension spring 22 will apply tension to the two L-shaped arms 24, so that the two clamping jaws 21 are quickly retracted. The elastic rope 23 continues to pull the two clamping jaws 21 during the process to ensure that the two clamping jaws 21 move stably in the preset direction without deviation during the retraction process, thereby achieving effective clamping of the object.

[0026] To restore the bistable mechanism 20 to its original state, the reset mechanism 30 only needs to apply a thrust to the two L-shaped arms 24 to reset the tension spring 22 to the position of the initial stable state. Therefore, the reset mechanism 30 can be implemented using various push rods 32 and telescopic rod structures.

[0027] Obviously, after adopting the above embodiment, the two jaws 21 can be controlled to move in an open state to the position where clamping is required, and then by controlling the two jaws 21 to move, the jaws 21 touch the object to be clamped, and the two jaws 21 will automatically close and clamp the object to be clamped; in this process, there is no need for an external drive device as an energy source to control the closing and clamping of the two jaws 21, thereby effectively solving the problem that the existing manipulator must rely on an active drive device for clamping operations.

[0028] like Figure 1 As shown, in this embodiment, a plurality of mounting through holes 11 are preferably provided on a side of the frame 10 away from the bistable mechanism 20 .

[0029] After adopting this setting method, the passive multifunctional mechanical gripper can be fixed to the mechanical arm or other device where it is needed by using screws and bolts passing through the mounting through-holes 11 .

[0030] like Figure 1 、 Figure 3 and Figure 6 As shown, in this embodiment, it is preferred that both jaws 21 are provided with strip grooves 25, and the two grooves 25 form an obtuse angle with the two jaws 21; the frame 10 is provided with pins 12 on opposite sides, and the two pins 12 pass through the two grooves 25 respectively, and the two pins 12 are the rotation axes of the two jaws 21.

[0031] After adopting this arrangement, a larger movement space can be provided for the two clamping jaws 21, so that the two clamping jaws 21 can be brought closer together, thereby strengthening the clamping force on the object.

[0032] like Figure 3 As shown, this embodiment preferably provides two L-shaped arms 24 including a long arm section 241 and a short arm section 242 vertically connected to each other, the opposite surfaces of the two clamping jaws 21 are respectively connected with the long arm section 241, the two short arm sections 242 are respectively extended toward the opposite long arm sections 241, and a tension spring 22 is connected between the two short arm sections 242.

[0033] like Figure 1 、 Figure 5 and Figure 6 As shown, this embodiment preferably provides a reset mechanism 30 including a button 31, a push rod 32, a push plate 33 and a pressure spring 34; the button 31 and the bistable mechanism 20 are respectively arranged on opposite sides of the frame 10; one end of the push rod 32 is connected to the button 31, and the other end of the push rod 32 passes through the frame 10 and is connected to the push plate 33; the push plate 33 is placed opposite to the two L-shaped arms 24; the pressure spring 34 is sleeved on the outside of the push rod 32, and the pressure spring 34 is compressed between the button 31 and the frame 10.

[0034] For example, in the initial state, the pressure spring 34 will push the button 31 upward, thereby driving the push plate 33 and the two L-shaped arms 24 to separate from each other to avoid affecting the state conversion of the bistable mechanism 20; and when the bistable mechanism 20 needs to be changed to the open state, the button 31 can be pressed downward to drive the push plate 33 to move downward until it contacts the two L-shaped arms 24, thereby pushing the two clamping jaws 21 back to the open state.

[0035] like Figure 1 、 Figure 5 and Figure 6 As shown, in this embodiment, the reset mechanism 30 preferably further includes a graphite guide rail 35 , and the graphite guide rail 35 is sleeved outside the push rod 32 .

[0036] After adopting this configuration, the friction force generated by the push rod 32 during the movement can be reduced, so that the push rod 32 can move more smoothly in the graphite guide rail 35.

[0037] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A passive multifunctional mechanical gripper based on a bistable mechanism, characterized in that: It comprises a frame and a bistable mechanism and a reset mechanism arranged on the frame; The bistable mechanism includes a clamping jaw, a tension spring, and an elastic rope; the two clamping jaws are rotatably mounted on opposite sides of the frame, and L-shaped arms are provided on the opposing surfaces of the two clamping jaws. The two L-shaped arms are respectively connected to the two ends of the tension spring, so that when the two clamping jaws are opened, the tension spring is placed in the space surrounded by the two L-shaped arms; there are multiple elastic ropes, and the ends of the multiple elastic ropes are respectively connected to the peripheral sides of the two clamping jaws; The two L-shaped arms include a long arm section and a short arm section that are perpendicularly connected to each other, the long arm sections are connected to the opposite surfaces of the two clamping jaws, the two short arm sections extend toward the opposite long arm sections, and the tension spring is connected between the two short arm sections; When the two clamping jaws are not subjected to external force, the tension spring is used to maintain the open state of the two clamping jaws; When the two clamping jaws are subjected to external force, the tension spring is used to drive the clamping jaws to close, and the multiple elastic ropes are used to maintain the clamping process without deviation; The reset mechanism is used to apply a thrust to the two L-shaped arms so as to reset the two clamping jaws to an open state.

2. The passive multifunctional mechanical gripper according to claim 1, characterized in that: A plurality of mounting through holes are provided on a side of the frame away from the bistable mechanism.

3. The passive multifunctional mechanical gripper according to claim 1, characterized in that: The two clamping jaws are each provided with a strip groove, and the two strip grooves form an obtuse angle with the two clamping jaws respectively; The two opposite sides of the frame are each provided with a latch, and the two latches respectively pass through the two strip-shaped grooves, and the two latches are respectively the rotation axes of the two clamping claws.

4. The passive multifunctional mechanical gripper according to claim 1, characterized in that: The reset mechanism includes a button, a push rod, a push plate and a pressure spring; The button and the bistable mechanism are respectively arranged on two opposite sides of the frame; One end of the push rod is connected to the button, and the other end of the push rod passes through the frame and is connected to the push plate; The push plate is placed opposite to the two L-shaped arms; The pressure spring is sleeved outside the push rod, and the pressure spring is compressed between the button and the frame.

5. The passive multifunctional mechanical gripper according to claim 4, characterized in that: The reset mechanism further includes a graphite guide rail, which is sleeved outside the push rod.

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