CN104565215A - Novel artificial hand flexible transmission control mechanism - Google Patents

Abstract

The invention discloses a novel artificial hand flexible transmission control mechanism, which is composed of a planetary gear mechanism, a switching mechanism, an artificial hand, and a hand clip; wherein, the planetary gear in the planetary gear mechanism adopts a double-connected planetary gear, and the sun gear directly cooperates with the input shaft As the input end, the internal gear is fixed on the shell of the artificial hand, and the planet carrier is fixedly connected with the sleeve as the output end; in the switching mechanism, the outer ring of the switching mechanism is directly fixed with the sleeve through screws as the input end, and the roller and output The shaft is used as the output end, and the shift fork is connected to the switching mechanism through the guide column. Through the joint action of the arc-shaped push rod and the spring, the guide column slides along the sliding groove, driving the artificial hand to open and close flexibly, realizing reliable, flexible and continuous switching . The artificial hand flexible transmission control mechanism adopts double planetary gear transmission, which minimizes the size while meeting the transmission ratio requirements, increases the degree of meshing, improves efficiency, and reduces noise.

Description

A New Type of Artificial Hand Flexible Transmission and Control Mechanism

technical field

The invention relates to a transmission mechanism of an artificial hand, in particular to a novel flexible transmission and manipulation mechanism of an artificial hand.

Background technique

At present, scholars at home and abroad have done a lot of research on myoelectrically controlled prosthetic hands, and have achieved certain results. The typical representative is the German OttoBack company. The SUVA myoelectric prosthetic hand developed by it is a single-degree-of-freedom three-finger prosthetic hand sll, and its control system includes two Road EMG signal processing part, excitation system and position control system; KnezoAkazwaa et al. of Kobe University in Japan developed a new type of myoelectric control bionic Kobe hand, which can imitate the dynamic characteristics of the neuromuscular control system of the human hand, so that the myoelectric hand can move through the fingers Position control system, force feedback, and variable gain in response to commands from the neuromuscular control system (A. Cranny, D.P.J. Cotton, P.H. Chappell, S.P. Beeby, N.M. White. Thick film force slide sensor prosthetic hand. Sensors and Actuators. A 123– 124 (2005) 162–171: R.G.E.Clement, K.E.Bugler, C.W.Oliver. Bionic prosthetic hands: A review of the state of the art and prospects for the future. The surgeon 9(2011) 336-340). Domestic research, such as the real-time control prosthetic hand of Harbin Institute of Technology ("Real-time control method of three-degree-of-freedom myoelectric prosthetic hand based on DSP", Acta Aeronautical Science, 2007, 28(5): 1257-1261); the self-adaptive ability of Tsinghua University Automatic switching booster mechanism. This mechanism uses a clutch to realize the function of switching speed, but there are two obvious deficiencies in it. First, the spring of the clutch is not easy to determine, and the fork with a large elastic force is not easy to move the roller. Cause slow action or even action failure; secondly, there is a rigid impact in the contact process between the roller and the outer ring, which produces vibration and noise, which does not achieve the desired effect for the user.

Contents of the invention

In order to avoid the shortcomings of the existing technology and overcome the problems of poor transmission reliability, long response time and slow movement of the artificial hand, the present invention proposes a novel artificial hand flexible transmission and control mechanism.

The technical solution adopted by the present invention to solve the technical problems is: comprising a planetary gear mechanism, a switching mechanism, an artificial hand, an incomplete gear, a worm wheel, a worm screw, and a hand clip, and it is characterized in that: the planetary gear mechanism comprises a double planetary gear, Small transmission ratio planetary gear mechanism, first output shaft, input shaft, second sun gear, planetary gear, first sun gear, first internal gear, planet carrier, electric motor, first double gear, second double gear, The high-speed sleeve, low-speed sleeve, the motor and the first output shaft are connected through a coupling, and the first output shaft cooperates with the second sun gear of the small transmission ratio planetary gear mechanism to drive the planetary gear to rotate. The first sun gear and the input shaft Fixed connection, the first internal gear is fixed on the artificial hand shell, the input shaft is fixedly connected to the high-speed sleeve, the planetary carrier is fixedly connected to the low-speed sleeve, and connected to the input shaft, the first sun gear drives the planetary carrier to rotate, double The second duplex gear of the planetary gear meshes with the first sun gear, and the first duplex gear of the duplex planetary gear meshes with the first internal gear; the small transmission ratio planetary gear mechanism is firmly connected with the hand clip;

The switching mechanism includes switch A, switch B, pin A, pin B, friction block, spring, outer sleeve, roller, arc push rod, guide column, torsion spring, sleeve concave tooth groove, dial Fork, the second output shaft, switcher A and switcher B have the same structure, the outer sleeve of switcher A is fixedly connected with the high-speed sleeve, the outer sleeve of switcher B is fixedly connected with the low-speed sleeve, and the second output shaft is connected with The roller is fixedly connected through the shaft hole; the friction block is composed of multiple sector blocks, the friction block is fixed in the sliding groove of the roller, the spring is installed in the positioning hole on the roller, the other end of the spring is connected to the friction block, and the guide post is fixed on the On the roller, the shift fork is connected to the roller through the pin B. There are U-shaped grooves at both ends of the shift fork to cooperate with the guide column, and the guide column slides in the U-shaped groove; one end of the torsion spring is fixedly connected with the output shaft, and the other end is connected with the pin B connection, one end of the arc-shaped push rod is connected with the pin A on the roller, and is connected with the pin at the bottom end of the friction block to form a rotating pair, the roller at the other end of the arc-shaped push rod is in contact with the arched working surface of the shift fork, in the spring Under the action of the arc-shaped push rod, the friction block slides up and down along the sliding groove, the convex teeth of the friction block cooperate with the concave tooth grooves of the outer sleeve, the switch A engages, the convex teeth of the friction block and the outer sleeve The grooves of the sleeve are separated, and the switch B is disengaged; the switching mechanism cooperates with the worm, worm wheel and incomplete gear through the second output shaft to drive the artificial hand to open and close.

The friction block is made of rubber material, and the coefficient of friction is 0.7-0.9.

Beneficial effect

The new artificial hand flexible transmission control mechanism proposed by the present invention adopts double planetary gear transmission, which minimizes the volume and occupies space while meeting the transmission ratio requirements; at the same time, it increases the degree of meshing overlap and improves efficiency. Reduced noise. The switching mechanism composed of switcher A and switcher B is adopted. Firstly, the top of the friction block of the switcher uses scattered seven sector blocks to ensure that it can still fully cooperate with the sleeve after wear and tear during manufacturing, installation and use. High reliability is achieved; secondly, the tooth-shaped protrusion at the top of the fan-shaped block is made of special rubber material, which not only increases the friction coefficient with the concave tooth groove of the sleeve, but also has a friction coefficient of 0.7-0.9, and its own plasticity makes it Fully fitting the tooth-shaped groove increases the friction force area and improves the friction efficiency; finally, the rubber material is used to reduce the weight of the components, reduce the vibration and impact during contact, and reduce the noise; thus achieving better The function of flexible transmission. The arc-shaped push rod is well integrated with the principle of leverage, and the friction block can be pushed with a small force, and it can be tightly combined with the sleeve to have a good effect, which improves the response sensitivity and efficiency; secondly, the arc The shaped end uses small rollers to contact the working surface of the shift fork, and uses rolling instead of sliding, which reduces the friction of the contact surface and improves the efficiency. The transmission mechanism is continuous, reliable, agile and efficient.

Description of drawings

A new artificial hand flexible transmission and manipulation mechanism of the present invention will be further described in detail in conjunction with the accompanying drawings and embodiments.

Fig. 1 is a schematic diagram of the flexible transmission and manipulation mechanism of the artificial hand of the present invention.

Fig. 2 is a sectional view of switch A of the flexible transmission and manipulation mechanism of the artificial hand of the present invention.

Fig. 3 is a sectional view of the switch B of the flexible transmission and manipulation mechanism of the artificial hand of the present invention.

Fig. 4 is a schematic diagram of a switch of the flexible transmission and manipulation mechanism of the artificial hand of the present invention.

Fig. 5 is a schematic diagram of the separation of the convex teeth of the friction block and the grooves of the inner concave teeth of the outer sleeve according to the present invention.

Fig. 6 is a schematic diagram of the engagement between the convex teeth of the friction block and the concave teeth grooves in the outer sleeve according to the present invention.

Fig. 7 is a schematic diagram of the engagement of the switcher A of the flexible transmission and manipulation mechanism of the artificial hand of the present invention.

Fig. 8 is a schematic diagram of disengaging switcher B of the flexible transmission and manipulation mechanism of the artificial hand of the present invention.

Fig. 9 is a schematic diagram of disengaging switcher A of the flexible transmission and manipulation mechanism of the artificial hand of the present invention.

Fig. 10 is a schematic diagram of the engagement of the switcher B of the flexible transmission and manipulation mechanism of the artificial hand of the present invention.

Fig. 11 is a schematic diagram of the transmission of the flexible transmission and manipulation mechanism of the artificial hand of the present invention.

In the picture:

1. Artificial hand 2. Incomplete gear 3. Worm gear 4. Worm 5. Screw 6. Shift fork 7. High speed sleeve 8. Low speed sleeve 9. First internal gear 10. First double gear 11. Second double Coupled gear 12. Planet carrier 13. First sun gear 14. Hand clamp 15. Motor 16. Bolt 17. Limit ring 18. Second internal gear 19. Planetary gear 20. Key A 21. Second sun gear 22. Screw Hole 23. Key 24. Sleeve concave tooth groove 25. Friction block 26. Pin A 27. Pin B 28. Torsion spring 29. Spring 30. Sliding groove 31. Shaft hole 32. U-shaped groove 33. Guide column 34 .Arc-shaped push rod 35.Outer sleeve 36.Roller 37.First output shaft 38.Input shaft 39.Small transmission ratio planetary gear mechanism 40.Double planetary gear 41.Switcher A 42.Switcher B43.Second Output shaft

Detailed ways

This embodiment is a novel artificial hand flexible transmission and manipulation mechanism.

Referring to Figures 1 to 11, the artificial hand flexible transmission control mechanism is composed of a planetary gear mechanism, a switching mechanism, an artificial hand, and a hand clip. The myoelectric control signal generated by the brain is transmitted to the control circuit of the motor. After the control circuit outputs the control signal to the motor, the motor starts to work, and the speed is output to the planetary gear mechanism through the output shaft. The planetary gear mechanism includes a double planetary gear 40, a small transmission ratio planetary gear mechanism 39, a first output shaft 37, an input shaft 38, a second sun gear 21, a planetary gear 19, a first sun gear 13, a first internal gear 9, Planet carrier 12, motor 15, first double gear 10, second double gear 11, high-speed sleeve 7, low-speed sleeve 8; motor 15 is connected with the first output shaft 37 through a coupling, and the first output shaft 37 Cooperate with the second sun gear 21 of the small transmission ratio planetary gear mechanism 39 to drive the planetary gear 19 to rotate; the first sun gear 13 is fixedly connected with the input shaft 38, the first internal gear 9 is fixed on the artificial hand housing, and the input shaft 38 It is fixedly connected with the high-speed sleeve 7, drives the high-speed sleeve 7 to rotate and output speed I, and drives the first sun gear 13 of the planetary gear mechanism to rotate together as the input end. The second double gear 11 of the double planetary gear 40 meshes with the first sun gear 13, and the first double gear 10 of the double planetary gear 40 meshes with the first internal gear 9; the planet carrier 12 is used as the output end and the low-speed sleeve 8 fixed connections. The high speed input by the first sun gear 13 drives the planetary carrier 12 to rotate after deceleration, because the planetary carrier 12 is fixedly connected with the low-speed sleeve 8 through the key 23, and then drives the low-speed sleeve 8 to rotate, and the output speed II. The rotational speed output by the motor 15 is divided into two parts: output rotational speed I and output rotational speed II, which respectively drive the high-speed sleeve 7 and the low-speed sleeve 8 to rotate, making them rotate at different rotational speeds. The key A20 in the small transmission ratio planetary gear mechanism 39 plays a transmission role, and the limit ring 17 is used for positioning, and the small transmission ratio planetary gear mechanism 39 is fixedly connected with the hand clip 14 by bolts 16 .

The switching mechanism is composed of switcher A41, switcher B42, pin A26, pin B27, friction block 25, spring 29, outer sleeve 35, roller 36, arc push rod 34, guide column 33, torsion spring 28, sleeve The concave tooth groove 24, the shift fork 6, and the second output shaft 43 are composed; the switcher A has the same structure as the switcher B, and the high-speed sleeve 7 and the low-speed sleeve 8 pass through the outer sleeve 35 of the switcher A41 and the switcher B42 respectively. The screws are fixedly connected together as the input terminal. The second output shaft 43 is fixedly connected with the roller 36 through the shaft hole 31 . The friction block 25 is composed of a plurality of sector blocks, the friction block 25 is fixedly connected in the sliding groove of the roller 36, the spring is installed in the positioning hole on the roller 36, the other end of the spring is connected to the friction block, and the guide column 33 is fixed on the roller 36 , the shift fork 6 is connected with the roller 36 through the pin B27, there are U-shaped grooves at both ends of the shift fork to cooperate with the guide column 33, and the guide column 33 slides in the U-shaped groove; one end of the torsion spring 28 is fixedly connected with the output shaft 43, and the other One end is connected with the pin B27, one end of the arc-shaped push rod 34 is connected with the pin A26 on the roller 36, and is connected with the pin at the bottom end of the friction block 25 to form a rotating pair, and the roller at the other end of the arc-shaped push rod 34 is connected with the shift fork 6 The arched working surface contacts; the friction block 25 slides up and down along the sliding groove 30 under the action of the spring 29 and the arc push rod 34; the friction block is made of rubber material, and the friction coefficient is 0.7-0.9.

At the beginning, the shift fork 6 of the switcher A41 is at the left limit position of the U-shaped groove 32. At this time, the roller of the arc-shaped push rod 34 is in contact with the lower end surface of the working surface of the shift fork 6. Under the action of the spring 29, the friction The convex teeth of the block 25 cooperate with the sleeve concave tooth groove 24 of the outer sleeve 35, and the switch A41 engages; the shift fork 6 of the switch B42 is at the right limit position of the U-shaped groove 32, and at this time, the arc push rod 34 The roller of the roller is in contact with the high-end surface of the working surface of the shift fork 6, the convex tooth of the friction block 25 is separated from the sleeve concave tooth groove 24 of the outer sleeve 35, and the switch B 42 is disengaged; the sliding groove 30 on the roller 36 makes the friction Block 25 slides up and down, and makes roller 36 do rotary motion simultaneously. The second output shaft 43 passes through the axle hole 31 on the roller 36 and is connected together with the roller 36 of the switcher A 41 and the switcher B 42 through the cooperation of the key. Since the switcher A41 is engaged, the switcher B42 is disengaged, and the switcher A41 The outer sleeve 35 of the output shaft 35 transmits the output speed I to the switch A 41, and the outer sleeve of the switch B 42 cannot transmit the output speed II to the switch B42, so the speed of the output shaft 43 is the speed of the switch A41 at this time, which comes from The output speed I is relatively high; at this time, the whole mechanism is in a high-speed rotation state, and it directly drives the artificial hand 1 to close quickly through the worm 4, the worm wheel 3 and the incomplete gear 2.

After the artificial hand 1 grasps the object, it continues to be blocked, causing the torsion spring 28 with one end fixed on the second output shaft 43 to be twisted and deformed. One end of the torsion spring 28 is fixed on the pin B27 of the shift fork 6, and when it is twisted and deformed, the shift fork 6 is moved by the pin B27. Due to the guiding effect of the guide post 33 on the roller 36 , the shift fork 6 starts to move in the matching direction between the U-shaped groove 32 and the guide post 33 . After the action is completed, the shift fork 6 of the switcher A41 is in the right limit position of the U-shaped groove 32. During this process, the arc-shaped push rod 34 rotates slightly around the pin A26, the roller end of the arc-shaped push rod 34 directly contacts the high-end surface of the working surface of the shift fork 6, and the convex teeth of the friction block 25 and the sleeve of the outer sleeve 35 The barrel grooves 24 separate. The shift fork 6 of the switcher B42 is at the left extreme position of the U-shaped groove 32. At this time, the roller end of the arc-shaped push rod 34 is directly in contact with the lower end of the working surface of the shift fork 6. Under the action of the spring 29, the friction block The convex teeth of 25 and the sleeve concave tooth groove 24 of the outer sleeve 35 are closely fitted together, and the switch B is engaged. Since the switcher A 41 is disengaged and the switcher B 42 is engaged, the outer sleeve 35 of the switcher B42 successfully transmits the output speed II to the switcher B42, but the outer sleeve 35 of the switcher A41 cannot transmit the rotational speed to the switcher A41 , so the rotational speed of the second output shaft 43 is the rotational speed of the roller 36 of the switcher B42, which comes from the output rotational speed II, the rotational speed is relatively low, but the torque is relatively large. At this time, the whole mechanism is in a low-speed rotation state, achieving the effect of deceleration and force increase. The second output shaft 43 drives the artificial hand 1 to slowly grasp the target object through the worm screw 4, the worm wheel 3 and the incomplete gear 2; when the incomplete gear 2 turns out of the work area, the artificial hand 1 no longer closes, maintaining the existing The state of grasping the target object, then the brain generates a myoelectric control signal to control the motor 15 to stop, and the process of grabbing the target object is completed.

Claims (2)

1. a novel artificial hand Flexible Transmission operating mechanism, comprises planetary wheeling mechanism, switching mechanism, artificial hand, partial gear, worm gear, worm screw, hand presss from both sides, and it is characterized in that: described planetary wheeling mechanism comprises compound planet gear, close steps planetary gears, first output shaft, power shaft, second sun gear, planetary gear, first sun gear, first internal gear, planet carrier, motor, first duplicate gear, second duplicate gear, high speed sleeve, low speed sleeve, motor is connected by shaft coupling with the first output shaft, first output shaft coordinates with the second sun gear of close steps planetary gears, drive planetary gear rotates, first sun gear and power shaft are connected, first internal gear is fixed on artificial hand housing, power shaft and high speed sleeve are connected, planet carrier and low speed sleeve are connected, and be connected with power shaft, first sun gear drives planet carrier to rotate, and the second duplicate gear of compound planet gear engages with the first sun gear, and the first duplicate gear of compound planet gear engages with the first internal gear, close steps planetary gears and the clamping company of hand,

Described switching mechanism comprises switch A, switch B, pin A, pin B, brake pad, spring, outer sleeve, roller, arc push rod, lead, torsion spring, the recessed teeth groove of sleeve, shift fork, the second output shaft, switch A is identical with switch B structure, outer sleeve and the high speed sleeve of switch A are connected, outer sleeve and the low speed sleeve of switch B are connected, and the second output shaft and roller are connected by shaft hole matching; Brake pad is made up of multiple secter pat, brake pad is connected in the slide slot of roller, spring fitting is on roller in locating hole, the spring other end is connected on brake pad, lead is fixed on roller, shift fork is connected with roller by pin B, and shift fork two ends have U-type groove to coordinate with lead, and lead is sliding in U-type groove; One end and output shaft fixed connection, the other end is connected with pin B, and arc push rod one end is connected with the pin A on roller, and connects into revolute pair with the pin of brake pad bottom, and the roller of the arc push rod other end contacts with the arch working face of shift fork; Under the effect of spring and arc push rod, brake pad slides up and down along slide slot, the convex tooth of brake pad and the recessed tooth socket fit of sleeve of outer sleeve, and switch A engages, and the convex tooth of brake pad is separated with the recessed teeth groove of the sleeve of outer sleeve, and switch B throws off; Switching mechanism is coordinated with worm screw, worm gear and partial gear by the second output shaft, drives artificial hand folding.

2. novel artificial hand Flexible Transmission operating mechanism according to claim 1, is characterized in that: described brake pad adopts elastomeric material, and coefficient of friction is 0.7 ~ 0.9.