CN211220700U - Snake arm three degrees of freedom wrist joint - Google Patents

Abstract

The utility model relates to a three-degree-of-freedom wrist joint of a serpentine arm, which comprises a bracket, a slewing motor and a differential mechanism. The motor, the end of the output shaft of the differential motor is fixedly installed with a bevel gear A, the pitch axis is horizontally placed above the bevel gear A, and the bevel gear B and bevel gear C meshing with the bevel gear A are fixed on the pitch axis. After being rotatably connected with the bracket, a yaw shaft is arranged between the pitch shafts on both sides, and the two ends of the yaw shaft are respectively connected with the pitch shaft for rotation. The installation shaft is installed on the yaw shaft, and the installation shaft is sleeved with bevel gears C on both sides for meshing transmission. The bevel gear D, the joint of the present invention can realize three different types of motion: yaw, pitch and rotation. The pitch and yaw are driven by two motors together, and the ratio of the output torque to the self-weight of the joint is large, which can effectively reduce the weight and reduce the volume. The rotation is directly driven by the motor, and the control is simple.

Description

Snake arm three degrees of freedom wrist joint

technical field

The utility model relates to a three-degree-of-freedom wrist joint of a serpentine arm.

Background technique

A snake robot is a robot that can imitate the movement of snakes. Rigid-structured snake robots can be modular, through the concatenation of single-degree-of-freedom modules or multi-degree-of-freedom modules of the same or similar structure. Common joint connection forms of snake robots include parallel connection, orthogonal connection, universal joint, and P-R connection. The joints of these four types of joints of the snake-like robot are generally single-degree-of-freedom or two-degree-of-freedom, and the dexterity of the snake-like robot is limited. However, the existing multi-degree-of-freedom joints are often bulky and difficult to be widely used.

Utility model content

The utility model proposes a three-degree-of-freedom wrist joint of a serpentine arm.

The solution adopted by the utility model to solve the technical problem is that a serpentine arm three-degree-of-freedom wrist joint includes a bracket, a rotary motor that drives the bracket to rotate, and a differential mechanism installed on the bracket, and the middle part of the lower side of the bracket is fixedly installed on the rotary The end of the output shaft of the motor;

The differential mechanism includes a differential motor symmetrically arranged on both sides of the slewing mechanism, a bevel gear A is fixedly installed at the end of the output shaft of the differential motor, and a pitch axis is placed horizontally above the bevel gear A, and the pitch axis is from the outside. The bevel gear B and the bevel gear C meshed with the bevel gear A are fixedly installed in the built-in in turn. The outer end of the pitch shaft is rotatably connected to the bracket through the bearing seat. The two ends of the yaw shaft are respectively connected to the pitch shafts on both sides through the bearing A. The middle part of the yaw shaft extends radially outward from the installation shaft. The installation shaft is sleeved with a bevel gear D which meshes with the bevel gear C on both sides. Gear D is rotatably matched with the installation shaft through bearing B.

Further, the bracket includes a bracket A and a bracket B, the bracket A includes a bottom plate, the left and right sides of the bottom plate are provided with side plates, the pitch axis is mounted on the side plates, the differential motor is mounted on the underside of the bottom plate, and the slewing motor is mounted on the bracket B. On the upper side, the bracket B is connected and fixed with the upper joint part, and the output shaft of the rotary motor is connected and fixed with the bottom plate.

Further, the output shaft of the rotating electrical machine is fixedly installed with a flange plate, and the flange plate is connected and fixed with the bottom plate by screws.

Further, the bevel gear A is sleeved on the output shaft of the differential motor, the side of the shaft of the bevel gear A is provided with a threaded hole for installing a set screw, and the bevel gear is locked on the output shaft of the differential motor through the set screw. The inner end of the bevel gear B abuts the inner end of the bevel gear C, the outer end of the bevel gear B abuts the shoulder on the pitch axis, the outer end of the bevel gear C abuts the sleeve, the sleeve is sleeved on the pitch axis, and the yaw shaft The ends are respectively sleeved on the inner ends of the pitch shafts on both sides, a bearing A is arranged between the yaw shaft and the pitch shaft, the bearing A abuts the sleeve, and the inner side of the end of the yaw shaft is provided with a shoulder for positioning the bearing A.

Further, the outer end of the installation shaft is locked with a retaining ring, the inner side of the large end opening of the bevel gear D is provided with a shoulder for locating the bearing B, the bearing B abuts the retaining ring, and the shaft end of the bevel gear D is evenly distributed with several Threaded holes for mounting end effectors.

Further, the rotary motor and the differential motor are both DC motors

Compared with the prior art, the utility model has the following beneficial effects: simple structure, reasonable design, many degrees of freedom, flexible movement, compact structure, and can realize three different types of movements of deflection, pitch and rotation, and pitch and deflection are composed of two. Driven by two motors together, the ratio of the output torque to the self-weight of the joint is large. The same driving force can be provided by a smaller motor, which can effectively reduce the weight and volume. The rotational freedom is directly driven by the motor, and the control is simpler.

Description of drawings

The utility model patent is further described below in conjunction with the accompanying drawings.

Figure 1 is a schematic diagram of the overall structure of the wrist joint;

Figure 2 is a front view of the wrist joint;

Figure 3 is the right side view of the wrist joint;

Figure 4 is a top view of the wrist joint;

FIG. 5 is a cross-sectional view of the transmission part of the differential mechanism.

In the figure: 1- bracket A; 2- differential motor; 6- bevel gear A; 8- side plate; 9- bearing seat; 11- washer; 15- pitch shaft; 16- bevel gear B; 17- bevel gear C; 18 - sleeve; 19 - deflection shaft; 20 - bevel gear D; 22 - retaining ring; 24 - rotary motor; 26 - bracket B; 27 - flange.

Detailed ways

The present utility model will be further described below with reference to the accompanying drawings and specific embodiments.

As shown in Figure 1-5, a serpentine arm three-degree-of-freedom wrist joint includes a bracket, a slewing motor that drives the bracket to rotate, and a differential mechanism installed on the bracket. The middle of the lower side of the bracket is fixedly installed on the output shaft of the slewing motor. end;

The differential mechanism includes a differential motor symmetrically arranged on both sides of the slewing mechanism, a bevel gear A is fixedly installed at the end of the output shaft of the differential motor, and a pitch axis is placed horizontally above the bevel gear A, and the pitch axis is from the outside. The bevel gear B and the bevel gear C which mesh with the bevel gear A and the bevel gear C are fixed and installed in sequence. The bevel gear B and the big end of the bevel gear C are in close contact. A deflection shaft is arranged between the shafts, and the two ends of the deflection shaft are respectively connected to the pitch shafts on both sides through the bearing A. The installation shaft extends radially outward from the middle of the deflection shaft. The bevel gear C on the side meshes with the bevel gear D of the transmission, and the bevel gear D rotates with the installation shaft through the bearing B.

In this embodiment, the bracket A and the bracket B, the bracket A includes a bottom plate, the left and right sides of the bottom plate are provided with side plates, the pitch axis is mounted on the side plates, the differential motor is mounted on the underside of the bottom plate, and the slewing motor is mounted on the bracket On B, the bracket B is connected and fixed with the previous joint part, and the output shaft of the rotary motor is connected and fixed with the bottom plate.

In this embodiment, the pitch axis is installed on the side plate through the bearing C, the side plate is fixedly installed with a sleeve member in the lateral direction, the inner bottom plate of the sleeve member is provided with a gasket, the bearing C is installed in the sleeve member, and the gasket Axial positioning of bearing C is achieved.

In this embodiment, each bearing is a miniature bearing.

In this embodiment, the output shaft of the rotating electrical machine is fixedly installed with a flange plate, and the flange plate is connected and fixed with the bottom plate by screws.

In this embodiment, the bevel gear A is sleeved on the output shaft of the differential motor, the side of one shaft of the bevel gear A is provided with a threaded hole for installing a set screw, and the bevel gear is locked on the differential motor through the set screw On the output shaft of the bevel gear B, the inner end of the bevel gear B abuts the inner end of the bevel gear C, the outer end of the bevel gear B abuts the shoulder on the pitch axis, the outer end of the bevel gear C abuts the sleeve, and the sleeve is sleeved on the pitch axis, The two ends of the yaw shaft are respectively sleeved on the inner ends of the two sides of the pitch shaft. A bearing A is arranged between the yaw shaft and the pitch shaft.

In this embodiment, the outer end of the installation shaft is locked with a retaining ring, the inner side of the large end opening of the bevel gear D is provided with a shoulder for locating the bearing B, the bearing B abuts the retaining ring, and the shaft end of the bevel gear D is both There are several threaded holes for installing the end effector.

In this embodiment, the rotary motor and the differential motor are both DC motors

The motion of the three-degree-of-freedom wrist joint of the snake-shaped arm is as follows:

Pitching motion: The two rotary motors rotate at the same speed and in the same direction, so that the two bevel gears C move at the same speed and in the same direction, and the bevel gear D rotates around the axis of the pitching axis to realize the pitching action of the joint;

Deflection motion: The two rotary motors rotate in opposite directions at the same speed, so that the two bevel gears C move in opposite directions at the same speed, and the bevel gear D rotates around the axis of the deflection axis to realize the deflection action of the joint;

Rotary motion: The rotary motor drives the bracket to rotate to realize the rotary motion of the joint;

Compound motion: The differential rotation of the two rotary motors makes the two bevel gears C perform differential motion, and the bevel gear D rotates around the axis of the pitch axis and the axis of the yaw axis at the same time to realize the compound motion of the joints for pitch and yaw.

The preferred embodiments listed above further describe the purpose, technical solutions and advantages of the present invention in detail. It should be understood that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (6)

1. A three-degree-of-freedom wrist joint with a snake-shaped arm is characterized in that: the differential mechanism is arranged on the bracket, and the middle part of the lower side surface of the bracket is fixedly arranged at the tail end of an output shaft of the rotary motor;

the differential mechanism comprises differential motors which are arranged on two sides of the swing mechanism in a bilateral symmetry mode, bevel gears A are fixedly mounted at the tail ends of output shafts of the differential motors, a pitch shaft is transversely arranged above the bevel gears A, bevel gears B and bevel gears C which are in meshing transmission with the bevel gears A are fixedly mounted on the pitch shaft from the outside to the inside in sequence, the outer ends of the pitch shafts are in rotating connection with the support through bearing seats, deflection shafts which are coaxial with the pitch shafts are arranged between the pitch shafts on the two sides, two ends of each deflection shaft are in rotating connection with the pitch shafts on the two sides through bearings A respectively, mounting shafts extend outwards from the middle parts of the deflection shafts in the radial direction, bevel gears D which are in meshing transmission with the bevel gears C on the two sides are sleeved.

2. The serpentine arm three-degree-of-freedom wrist joint according to claim 1, wherein: the support includes support A, support B, and support A includes the bottom plate, and the bottom plate left and right sides is equipped with the curb plate, and the every single move axle is installed on the curb plate, and differential motor installs at the bottom plate downside, and rotary motor installs on support B, and support B is connected fixedly with last joint spare, and rotary motor's output shaft is connected fixedly with the bottom plate.

3. The serpentine arm three-degree-of-freedom wrist joint according to claim 2, wherein: and the output shaft of the rotating motor is fixedly provided with a flange plate, and the flange plate is fixedly connected with the bottom plate through screws.

4. The serpentine arm three-degree-of-freedom wrist joint according to claim 1, wherein: the bevel gear A is sleeved on an output shaft of the differential motor, a threaded hole used for installing a set screw is formed in one side face of the bevel gear A, the bevel gear is locked on the output shaft of the differential motor through the set screw, the inner end of the bevel gear B abuts against the inner end of the bevel gear C, the outer end of the bevel gear B abuts against a shaft shoulder on the pitch shaft, the outer end of the bevel gear C abuts against a sleeve, the sleeve is sleeved on the pitch shaft, two ends of a deflection shaft are respectively sleeved at the inner ends of the pitch shafts on two sides, a bearing A is arranged between the deflection shaft and the pitch shaft, the bearing A abuts against the sleeve, and a shaft shoulder used.

5. The serpentine arm three-degree-of-freedom wrist joint according to claim 1, wherein: the installation axle outer end lock solid has the retaining ring, and the main aspects trompil inboard of bevel gear D is offered and is used for fixing a position bearing B's shaft shoulder, and bearing B supports and leans on the retaining ring, and bevel gear D's axle head equipartition has a plurality of screw holes that are used for installing end effector.

6. The serpentine arm three-degree-of-freedom wrist joint according to claim 1, wherein: the rotary motor and the differential motor are both direct current motors.

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