CN108015800A - A kind of joint locking mechanism - Google Patents

Abstract

The present application provides a joint locking mechanism. The locking mechanism includes a first end cover, a second end cover, and an output shaft rotatably arranged between the first end cover and the second end cover. , a rotating rod rotatably arranged between the first end cover and the second end cover, a guide rod arranged between the first end cover and the second end cover, and the output shaft is fixed There is a friction disc, the first brake pad and the second brake pad are threadedly connected to the rotating rod, the rotation direction of the first brake pad and the second brake pad relative to the rotating rod is opposite, and the guide The rod passes through the first brake pad and the second brake pad, the first brake pad and the second brake pad are slidably arranged along the guide rod, and the first brake pad and the second brake pad The plates are located on both sides of the brake pads respectively, and compress the brake pads.

Description

A joint locking mechanism

technical field

The present application relates to a joint locking mechanism, in particular to a passive mechanical arm joint locking mechanism based on the disc brake principle.

Background technique

In recent years, with the mature application of medical robots such as da Vinci, medical robots have developed into an important branch of the field of robotics, and it is also an important research direction in the field of biomedical engineering. Nearly 30 years of medical robot research and clinical practice have shown that a huge obstacle that restricts medical robots from entering the clinic is the safety of robots, especially that robots are power-driven open-loop devices that directly interact with doctors and patients. This creates a lot of psychological pressure on many clinicians. Therefore, the development of passive robotic arms that do not require power to assist in navigation surgery or the installation of micro powered surgical robots has become the focus of medical robot research and development in recent years.

The core of the passive manipulator lies in the development of the joint locking mechanism. At present, the joint locking mechanism mainly adopts hydraulic, pneumatic, electromagnetic, mechanical and other methods. Due to the pollution of the operating room environment and the large size of the equipment, the hydraulic and pneumatic methods are very limited in application. The basic principle of electromagnetic locking is similar to that of power-off brakes, and the structure is simple, but the locking force is not high under micro conditions. Therefore, the purely mechanical locking joint locking mechanism is the most ideal way. The pure mechanical locking method has a simple structure and is easy to operate. The environment is polluted.

application content

In order to meet the demand for passive mechanical arms in medical clinics, the present application provides a modular passive mechanical arm joint locking mechanism.

In order to solve the above technical problems, the present application provides a joint locking mechanism, the locking mechanism includes a first end cover, a second end cover, rotatably arranged on the first end cover and the second end cover an output shaft between the covers, a rotating rod rotatably arranged between the first end cover and the second end cover, a guide rod arranged between the first end cover and the second end cover, The output shaft is fixed with a friction disc, the first brake pad and the second brake pad are screwed on the rotating rod, and the first brake pad and the second brake pad are relative to the direction of rotation of the rotating rod. On the contrary, the guide rod passes through the first brake pad and the second brake pad, and the first brake pad and the second brake pad are slidably arranged along the guide rod, and the first brake pad and the second brake pad are slidably arranged along the guide rod. The brake pad and the second brake pad are respectively located on both sides of the brake pad, and press the brake pad.

Preferably, the rotating rod is provided with a locking spring for applying a rotating force to the rotating rod, the locking spring is a torsion spring, one end is fixed on the first end cover, and the other end is fixed on the rotating rod.

Preferably, the locking mechanism further includes a manual unlocking assembly, and the manual unlocking assembly includes a swing rod whose end is fixedly connected to the rotating rod, and a rope connected to the swing rod.

Preferably, the manual unlocking assembly further includes a pulley bracket mounted on the first end cover, a first pulley and a second pulley mounted on the pulley bracket, and the direction of the rotation axis of the second pulley is the same as The linear directions where the rotation axes are located are perpendicular to each other, the rotation axis direction of the first pulley and the rotation axis direction of the second pulley are arranged perpendicular to each other, and the ropes go around the first pulley and the second pulley in turn Connect with described fork afterward.

Preferably, a first sleeve and a second sleeve are fixedly sleeved on the rotating rod, the first brake pad is screwed to the first sleeve, and the second brake pad is connected to the first sleeve. The second sleeve threaded connection described above.

Preferably, the first brake pad and the second brake pad are provided with a first through hole for the rotation rod to pass through, a second through hole for the guide rod to pass through, and a second through hole for the output shaft to pass through. Through the recessed area that is recessed away from the output shaft, the opposite surfaces of the first brake pad and the second brake pad are also provided with installation grooves, and friction plates are arranged in the installation grooves.

A joint locking mechanism described in the present application is a passive mechanical arm joint locking mechanism for medical operations, and realizes joint locking. Under the action of no external force, the first brake pad and the second brake pad press against the friction disc to lock the output shaft, and the output shaft stops rotating. The locking spring can apply a rotating force to the rotating rod, so that the rotating rod has a tendency to rotate, so that the first brake pad and the second brake pad have a tendency to move toward each other, thereby pressing against the friction disc. When an external force is applied to the rotating rod and the rotating rod is rotated in the opposite direction, the first brake pad and the second brake pad move away from each other, away from the friction disc, and the output shaft starts to rotate. The locking mechanism of the present application adopts the principle of butterfly brakes. Under normal circumstances, the torque of the spring is used to drive the screw drive to narrow the gap between the brake pads, lock the brake pads, and realize the locking of the output shaft of the joint. In addition, the locking mechanism is unlocked in a rope-driven manner, the rope is pulled, and the unlocking swing lever is rotated to drive the screw drive to increase the gap of the brake pads, loosen the brake pads, and realize the unlocking of the joint output shaft.

Description of drawings

Fig. 1 is a schematic structural view of a joint locking mechanism described in the present application;

Fig. 2 is a partial structural schematic diagram of a joint retraction mechanism described in the present application;

Fig. 3 is a partial structural schematic diagram of a joint retraction mechanism described in the present application;

Fig. 4 is a schematic structural view of the brake pad described in the present application,

Among them: 11. The first end cover; 12. The second end cover; 21. The rotating rod; 22. The first sleeve; 23. The second sleeve; 31. The first brake pad; 32. The second brake pad; 4 , guide rod; 5, locking spring; 61, friction disc; 81, first pulley; 82, second pulley; 83, pulley support; 84, rope; 85, swing bar; 311, first through hole; 312, The second through hole; 313, the installation groove; 314, the friction plate; 315, the depressed area.

Detailed ways

The application will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the application and implement it, but the examples given are not intended to limit the application.

As shown in the figure, it is a joint locking mechanism, and the locking mechanism includes a first end cover 11, a second end cover 12, and rotatably arranged on the first end cover 11 and the second end cover. 12 between the output shaft, rotatably arranged between the first end cover 11 and the second end cover 12 21, arranged between the first end cover 11 and the second end cover 12 Between the guide rod 4, the output shaft is fixed with a friction disc 61, the first brake pad 31 and the second brake pad 32 are threaded on the rotation rod 21, and the first brake pad 31 and the second brake pad 32 are screwed together. The rotation direction of the brake pads 32 relative to the rotating rod 21 is opposite, the guide rod 4 passes through the first brake pads 31 and the second brake pads 32, and the first brake pads 31 and the second brake pads The piece 32 is slidably arranged along the guide rod 4, and the first brake piece 31 and the second brake piece 32 are respectively located on two sides of the brake piece, and press the brake piece. A locking spring 5 for applying a rotational force to the rotating rod 21 is provided on the rotating rod 21. The locking spring 5 is a torsion spring, one end of which is fixed on the first end cover 11, and the other is One end is fixed on the said rotating rod 21. The locking spring 5 can apply a rotational force to the rotating rod 21, so that the rotating rod 21 has a tendency to rotate, so that the first brake pad 31 and the second brake pad 32 have a tendency to move toward each other, thereby pressing against the friction disc 61. The locking mechanism of the present application adopts the principle of butterfly brake. Under normal circumstances, the torque of the spring is used to drive the screw drive to narrow the gap between the brake pads, lock the brake pads, and realize the locking of the output shaft of the joint.

The locking mechanism further includes a manual unlocking assembly, and the manual unlocking assembly includes a swing rod 85 whose end is fixedly connected to the rotating rod 21 , and a rope 84 connected to the swing rod 85 . The manual unlocking assembly also includes a pulley bracket 83 installed on the first end cover 11, a first pulley 81 and a second pulley 82 installed on the pulley bracket 83, and the rotation of the second pulley 82 The direction of the axis is perpendicular to the direction of the straight line where the axis of rotation is located, the direction of the axis of rotation of the first pulley 81 is perpendicular to the direction of the axis of rotation of the second pulley 82, and the direction of the axis of rotation of the second pulley 82 is arranged perpendicularly. A pulley 81 and a second pulley 82 are connected with the swing bar 85 afterward. When it needs to be unlocked, it is only necessary to pull the rope 84, turn the unlocking swing lever 85, and the first brake pad 31 and the second brake pad 32 will move away from each other to drive the screw drive to increase the gap between the brake pads and realize the unlocking of the joint output shaft. When the rope 84 is released and the external force is removed, the rotating rod 21 rotates under the action of the locking spring 5, and the first brake pad 31 and the second brake pad 32 move towards the direction close to each other, and the rotating rod 21 is locked again.

The first sleeve 22 and the second sleeve 23 are fixedly sleeved on the rotating rod 21, the first brake pad 31 is threadedly connected with the first sleeve 22, and the second brake pad 32 is threadedly connected with the second sleeve 23. In a preferred embodiment, both ends of the first sleeve 22 and the second sleeve 23 are provided with protruding rings, and the protruding rings can prevent the first brake pad 31 and the second brake pad 32 from Break away from the sleeve, and when the rope 84 is pulled, the first brake pad 31 and the second brake pad 32 will not break away from the sleeve because the tension is too large.

Both the first brake pad 31 and the second brake pad 32 are provided with a first through hole 311 for the rotation rod 21 to pass through, a second through hole 312 for the guide rod 4 to pass through, The recessed area 315 for the output shaft to pass through is recessed away from the output shaft. The opposite surfaces of the first brake pad 31 and the second brake pad 32 are also provided with a mounting groove 313, and the installation groove 313 A friction plate 314 is provided. After the old friction lining 314 wears out, a new friction lining 314 can be replaced.

The working principle of the joint locking mechanism of the present application is as follows:

The present invention is a manually controlled medical passive mechanical arm joint locking mechanism, which is driven by a rope 84 . When the locking mechanism has no external force applied, due to the action of the locking spring 5 , the output shaft is compressed by the first brake pad 31 and the second brake pad 32 , and is in a static state. When an external force is applied, driven by the rope 84, the first brake pad 31 and the second brake pad 32 loosen the output shaft, and the output shaft rotates.

The first brake pad 31 and the second brake pad 32 are respectively designed with left and right helical threads, and the first sleeve 22 and the second sleeve 23 for gap adjustment matched with the first brake pad 31 and the second brake pad 32 are also designed correspondingly. right-handed thread. The first sleeve 22 and the second sleeve 23 are fixed on the rotating rod 21, and the rotating rod 21, the first sleeve 22 and the second sleeve 23 function as a screw rod as a whole. When the rotating rod 21 rotates, the first sleeve 22 and the second sleeve 23 also rotate together, so that the first brake pad 31 and the second brake pad 32 with different helical directions are in the first sleeve 22 and the second sleeve. The cylinder 23 moves closer to or apart from each other.

One end of the locking spring 5 is fixed on the first end cover 11 , and the other end is fixed on the swing rod 85 . The fork 85 is fixed with the rotating rod 21. The end of the fork 85 is connected to the rope 84. When the rope 84 is stressed, the fork 85 rotates to compress the locking spring 5, and simultaneously drives the rotation bar 21 and the first sleeve 22 and the second sleeve 23 to rotate, thereby making the first The brake pad 31 and the second brake pad 32 are separated from each other. The output shaft turns. When the active force is withdrawn, the locking spring 5 resets, and now the first brake pad 31 and the second brake pad 32 move closer again, and the output shaft stops rotating. Fork 85 only does the swing arm motion perpendicular to output shaft in this device.

The rope 84 passes through the grooves of the first pulley 81 and the second pulley 82 sequentially, and under the action of the first pulley 81 and the second pulley 82 , the turning of force is realized. Two pulleys are fixed on the pulley bracket 83.

The joint locking mechanism of the present invention includes two working states: 1. When no external force is applied, under the force of the locking spring 5, the first brake pad 31 and the second brake pad 32 press the friction disc 61 of the output shaft, The structure is locked. 2. When an external force is applied, the swing rod 85 swings to compress the locking spring 5, the first brake pad 31 and the second brake pad 32 leave the friction disc 61 of the output shaft, and the output shaft rotates. After the force is withdrawn, the locking spring 5 resets, and the mechanism is locked again.

The above-mentioned embodiments are only preferred embodiments for fully describing the present application, and the protection scope of the present application is not limited thereto. Equivalent substitutions or transformations made by those skilled in the art on the basis of the present application are all within the protection scope of the present application. The protection scope of the present application shall be determined by the claims.

Claims (6)

1. A joint locking mechanism, characterized in that, the locking mechanism comprises a first end cover, a second end cover, a rotatably arranged between the first end cover and the second end cover The output shaft, the rotating rod rotatably arranged between the first end cover and the second end cover, the guide rod arranged between the first end cover and the second end cover, the output The shaft is fixed with a friction disc, and the first brake pad and the second brake pad are threadedly connected to the rotating rod, and the rotation direction of the first brake pad and the second brake pad is opposite to that of the rotating rod. The guide rod passes through the first brake pad and the second brake pad, and the first brake pad and the second brake pad are slidably arranged along the guide rod, and the first brake pad and the second brake pad are slidably arranged. The two brake pads are respectively located on both sides of the brake pad, and press the brake pad. 2. A joint locking mechanism according to claim 1, wherein a locking spring for applying a rotational force to the rotating rod is provided on the rotating rod, and the locking spring It is a torsion spring, one end is fixed on the first end cover, and the other end is fixed on the rotating rod. 3. A joint locking mechanism according to claim 2, wherein said locking mechanism further comprises a manual unlocking assembly, said manual unlocking assembly includes an end fixed to said rotating rod The fork that connects, the rope that is connected with described fork. 4. A joint locking mechanism according to claim 3, wherein the manual unlocking assembly further comprises a pulley bracket mounted on the first end cover, a first pulley bracket mounted on the pulley bracket The pulley and the second pulley, the direction of the rotation axis of the second pulley is perpendicular to the direction of the straight line where the rotation axis is located, the direction of the rotation axis of the first pulley is mutually perpendicular to the direction of the rotation axis of the second pulley It is arranged vertically, and the said rope is connected with the said pendulum after going around the first pulley and the second pulley in turn. 5. A joint locking mechanism according to claim 2, wherein a first sleeve and a second sleeve are fixedly sleeved on the rotating rod, and the first brake pad and the The first sleeve is threadedly connected, and the second brake pad is threadedly connected with the second sleeve. 6. A joint locking mechanism as claimed in claim 5, characterized in that, the first brake pad and the second brake pad are provided with a first through hole for the rotation rod to pass through, for The second through hole through which the guide rod passes, the recessed area for the output shaft to pass through and is recessed away from the output shaft, and the opposite surface of the first brake pad and the second brake pad is also provided with a mounting The groove, the friction plate is arranged in the installation groove.