RU2664171C1 - Arm prosthesis for patients with the degree of amputation from fingers to the forearm, prosthesis of the wrist joint, which includes the hand prosthesis, the finger rod cable locking device of the hand prosthesis (3 options), the finger position combination control device of the hand prosthesis (2 options) - Google Patents

Abstract

FIELD: medicine.SUBSTANCE: group of inventions relates to the field of medical technology, namely to the active hand and forearm prostheses. Arm prosthesis for patients with a degree of amputation from the fingers to the forearm includes a hand prosthesis including the system of cables and pulleys, the forearm prosthesis and the wrist joint prothesis that connects the hand prosthesis to the forearm prosthesis. Wrist joint is formed by joining the hand and forearm by means of two flexible tubes with thickenings at the ends, each of which is fixed at one end in the wrist prosthesis, the other in the forearm prosthesis. Forearm contains the distal and proximal segments, which are connected by two flexible tubes that are fixed at both ends in the segments to be joined. Hand blocking device is installed in the hand. In the proximal segment of the forearm, there is the tension mechanism for the traction cable of the hand prosthesis and the hand unlocking angle regulator, which is a plate fixed to the surface of the proximal segment and configured with the possibility to extend beyond the segment and affect the hand blocking device installed, which is installed in the hand prosthesis. Hand prosthesis for the mentioned arm prosthesis includes the hand blocking device and the mechanical hand that comprises a metacarpus, the artificial fingers, which is connected to the metacarpus by means of joints and formed by the phalanges with channels that are connected with joints, through their channels the cables are stretched, the ends of which are fixed on the distal phalanxes and at the ends of the pulleys, which are connected by means of a cable with the cable tensioning unit. Joint, which connects the adjacent phalanges of the fingers and the phalanx with the metacarpus is an elastic elongated element with thickenings at the ends. On the metacarpus in the area of the base of the thumb there is a recess with coaxially fixed protrusions, in which the rotator is mounted with the formation of a rotation axis of the thumb, which is mounted on the rotator. On the one hand, the rotator contains denticles, which are located radially around the axis of thumb rotation. On one of the protrusions there is a spring, and around the other protrusion there are denticles on the wall of the recess, which, when the rotator is installed in the recess, engage with the denticles on the rotator. On the metacarpus between the fingers and the cable tension unit or between the cable tension unit and the proximal metacarpus portion there is provided with the finger combination control system, which includes at least one finger rod cable locking device, which is configured with the possibility to fix the cable. Prosthetic wrist joint for the mentioned arm prosthesis includes at least two flexible tubes with thickenings at the ends, each of which is fixed by means of screws with its one end in the hand prosthesis, with the other end – in the forearm prosthesis. Finger rod cable locking device of the mentioned hand prosthesis according to the first embodiment includes a hollow cylindrical body with a conical tip, a washer, between the cone-shaped tip and the washer there is a piston in the form of a hollow cylinder, the diameter of one end is equal to the diameter of the opening of the cylindrical body from the side of the cone-shaped tip and is movable in the opening of the housing, the other end abuts against the washer, the middle part of the piston has a diametrical wedge-shaped thickening. Spring is installed between the washer and the thickening of the piston. Ball bearing is radially installed in the internal channel of the piston. Cable passes through the channel, which is formed by the body cavity, the opening in the washer and the piston cavity. Device for locking the ropes of the fingers' rods of the mentioned hand prosthesis according to the second option includes the rack bar, onto which the rope cables are fixed on both sides, the rack wheel, which is mounted above the rack, which is in engagement with the teeth of the rack bar. Finger rod cable locking device of the mentioned hand prosthesis according to the third option includes the wedge, which is connected to the spring that is fixed in the hand body, where the cable passes between the wedge and the hand body. Finger position combination control system of the hand prosthesis according to the first option includes three lever-locking devices of the middle finger, of the ring finger and little finger, which are connected to the fingers by means of cables and connected by means of cables with the pulleys, with which by means of cables the locking device of the index finger is connected, two pulleys, which combine pairs of cables from the index and middle fingers, ring finger and little finger, are connected using the bar and are connected with cables to the locking device, which is combined by means of the lever with the thumb locking device, which is connected to the thumb with a ca

Description

The group of inventions relates to the field of medical technology, namely to active prostheses of the hand and forearm of the hands. This prosthesis is intended for children and adults with a degree of amputation from fingers to forearm. It is also suitable for patients with congenital defects of the hand and underdevelopment of the fingers.

The following solutions are known in the art.

Known prosthetic hand, including an artificial hand containing the body, the first finger, the block of the second or third fingers, the lever transmission, the drive function of the mobility of the "gripper-opening of the brush", as well as the mechanism of abduction-reduction of the second finger (RF patent No. 2472469, published 20.01. 2013).

A prosthetic arm is also known, including a mechanical hand containing a palm, artificial fingers formed by articulated hollow phalanges, veins for clenching artificial fingers into a fist, and return springs for straightening artificial fingers. The mechanical brush also contains a ratchet wheel with a pulley located under the ratchet wheel and having a perimeter groove to accommodate a bundle of veins, a ratchet dog, a ratchet for turning the ratchet wheel and a latch for holding the dog. At the same time, the veins for clenching the artificial fingers into a fist are fixed at the ends of the upper phalanges, skipped inside the artificial fingers, pass in the pulley of the ratchet wheel and are fixed in a cuff made with the possibility of installation above the elbow joint. Moreover, the artificial fingers are made with the possibility of clenching into a fist when bending the arm or turning the pulley with the help of a collar due to tension of the veins and with the possibility of straightening due to return springs, when straightening the arm or when the dog is disengaged from the ratchet tooth.

The closest analogue of the patented solution is a prosthesis of the hand, including a mechanical hand containing a palm, artificial fingers formed by articulated phalanges with channels through which cables are stretched, the ends of which are fixed to the upper phalanges, and channels through which gum is stretched, pinched by screws in of each phalanx, four fingers are combined in pairs through a system of cables and two pulleys combined by cables and a third pulley, which is combined with the thumb by means of three s and the fourth pulley connected via a cable to the cable tensioning unit, a protrusion with the axis of rotation of the thumb is made on the mechanical brush in the area of the base of the thumb, the base of the thumb is installed on the protrusion with cloves fixed on the protrusion by means of a spring and a button located in the cavity of the brush opposite the base of the thumb, while the base of the thumb is rotatable around the axis of rotation of the thumb.

The technical problem to be solved by the group of inventions is the need to expand the functionality of mechanical prostheses of the hand.

The technical result of the patented group of inventions is to increase the number of types of performed grips, gestures and manipulation of objects.

The claimed technical result is ensured by the design of the prosthesis of the hand, including the prosthesis of the hand, the prosthesis of the forearm and the prosthesis of the wrist joint connecting the prosthesis of the hand with the prosthesis of the forearm, The prosthesis of the wrist joint is formed by connecting the prosthesis of the hand and the prosthesis of the forearm through at least two flexible tubes with thickenings at the ends, each of which is fixed with one end in the prosthesis of the hand, the other in the prosthesis of the forearm, the prosthesis of the forearm contains at least two segments, connected at least one flexible tube.

The hand prosthesis includes a hand lock device and a mechanical hand containing a metacarpus, artificial fingers connected to the metacarpus by joints formed by phalanges connected by joints with channels through which cables are stretched, the ends of which are fixed to the distal phalanges and at the ends of pulleys connected by a cable with knot of a tension of cables. The joint connecting adjacent phalanges of the fingers and phalanx with the metacarpus is an elastic elongated element with thickenings at the ends. On the metacarpus in the region of the base of the thumb there is a recess with coaxially mounted protrusions, in which a rotator is installed with holes in which the protrusions enter to form the rotation axis of the thumb mounted on the rotator, while on one side the rotator contains teeth located radially around the rotation axis thumb, a spring is installed on one of the protrusions, and teeth are located around the other protrusion on the recess wall, which, when the rotator is installed in the recess, mesh with the teeth on the rotator. On the metacarpal between the fingers and the cable tensioning unit or between the cable tensioning unit and the proximal part of the metacarpus there is a control system for combining the position of the fingers, including at least one device for locking the cable rods, made with the possibility of fixing the cable.

Rod cables laid inside Teflon tubes placed inside the cable channels.

The phalanx of the finger is made of two parts, between which a thickened area of the joint is located and which are connected together by means of a bolt.

The surface of the distal phalanx and part of the proximal phalanx facing the palm of the palm have lining made of soft elastic material.

Part of the surface of the phalanx facing the palm is embossed.

The finger traction cable locking system according to the first embodiment includes a hollow cylindrical body with a cone-shaped tip, a washer fixed to the body, a piston in the form of a hollow cylinder is mounted between the cone-shaped tip and the washer, the diameter of one end is equal to the diameter of the hole of the cylindrical body from the side of the cone-shaped tip and is movable in the hole, the other end abuts the washer, the middle part of the piston has a diametrical wedge-shaped thickening, between the washer and the thickening of the piston Lena spring, in the inner piston channel a ball bearing is radially mounted.

The cable passes through the channel formed by the body cavity, the hole in the washer and the piston cavity.

The piston in the part facing the conical tip of the housing is connected to the lever-button.

The finger traction cable locking system according to the second embodiment includes a toothed rack, on which rods are fixed on both sides, a ratchet is installed above the rack, which is engaged with the rack teeth.

The finger traction cable locking system according to the third embodiment includes a wedge connected to a spring fixed in the brush body, while the cable passes between the wedge and the brush body.

The finger position combination control system according to the first embodiment includes three devices for locking the middle finger, ring finger and little finger connected by a lever, connected to the fingers by cables and connected by cables to the pulleys, to which the index finger locking device is connected via cables, two pulleys that combine in pairs cables from the index and middle fingers, ring finger and little finger, connected by a bar and connected by cables to a locking device, combined e via a lever with the thumb lock device connected to the thumb cable.

The finger position combination control system according to the second embodiment includes three middle finger, ring finger and little finger locking devices connected by a lever, connected to the fingers by cables and connected by cables to the pulleys, to which the index finger locking device is connected via cables, two pulleys that combine in pairs cables from the index and middle fingers, ring finger and little finger, connected by a bar and connected by cables to a locking device, combined e via a lever with the thumb lock device connected to the thumb cable.

The whole set of design features of the claimed prosthesis of the hand is aimed at expanding the functionality of the prosthesis by increasing the number of types of grip, gestures and manipulations and is suitable for people with paired amputation.

The mechanism of rotation of the thumb provides rotation and fixation of the position of the thumb without buttons of levers and locks, which allows people with paired amputation to use the prosthesis and extends the number of performed contractions and the functionality of the prosthesis.

The locking device allows you to grab the item and manipulate it without using a second hand, because after capture, the brush does not open. Functionality increases as in other prostheses, it is necessary to hold the wrist or elbow in a certain position, which greatly restricts movements and does not allow to manipulate objects without using a second hand. Function is necessary for people with paired amputation.

The design of the wrist joint and forearm has three degrees of freedom, as the wrist joint of a living hand and absolutely does not limit the freedom of the wrist joint and forearm. In similar prostheses, the wrist joint has only one degree of freedom and does not allow a person to manipulate objects in the wrist joint.

Gesture switching device. Allows you to choose the type of grip, which extends the functionality of the prosthesis and equates the active traction prosthesis in functionality with electromechanical prostheses. The prosthesis has the ability to mechanically program any set of grips.

Rod cables pass through Teflon tubes, which reduces the friction of the rods on the brush body, increases efficiency, prosthesis resource and grip force.

Mechanical fuses are made in the form of rubber joints, the design of which prevents mechanical destruction of the fingers and disengages the phalanges during overloads.

Next, the solution is illustrated by reference to the figures, which show the following.

FIG. 1 is a general view of the construction of a finger.

FIG. 2 - types of finger joints.

FIG. 3 - composition of the finger joint

FIG. 4 - a joint in the form of a thin-walled element with corrugated stiffeners.

FIG. 5 - structure of the finger.

FIG. 6 - structure of the finger.

FIG. 7 - the structure of the finger.

FIG. 8 - finger with overlays.

FIG. 9 - the structure of the body of the finger.

FIG. 10 is a general view of a mechanical brush.

FIG. 11 is a General view of the base of the thumb with the rotator of the thumb.

FIG. 12 is a general view of the base of the thumb.

FIG. 13 is a general view of the thumb.

FIG. 14 is a general view of the prosthetic arm in various positions.

FIG. 15 is a general view of the prosthetic arm in various positions.

Fig - a General view of the device locks rods in the first embodiment.

FIG. 17 is a diagram of the connection of the cables from the fingers and the linkage locking device according to the first embodiment.

FIG. 18 is a variant of the connection diagram of the cables from the fingers and the linkage locking device according to the first embodiment.

FIG. 19 is a variant of the connection diagram of the cables from the fingers and the linkage locking device according to the second embodiment.

FIG. 20 - cable locking device with a lever-button.

FIG. 21 is a top view of the linkage locking system of the second embodiment.

FIG. 22 is a side view of the link locking system according to the second embodiment.

FIG. 23 - linkage locking device according to the second embodiment in the unlocked state.

FIG. 24 - linkage locking device according to the second embodiment in the unlocked state and in the locked state.

FIG. 25 is a general view of the linkage locking system according to the third embodiment.

FIG. 26 is a general view of the prosthetic arm.

FIG. 27 is a sectional view of a prosthetic arm.

FIG. 28 - cable tensioning mechanism.

FIG. 29 - prosthetic arm mounted on the patient's arm.

FIG. 30 - sectional mechanical brush.

FIG. 31 - sectional view of a Teflon tube and cable.

FIG. 32 - types of combinations of positions of the fingers - grips.

FIG. 33 is a second embodiment of a control system for combinations of finger positions.

FIG. 34 is a first embodiment of a finger position combination control system.

FIG. 35 is a second embodiment of a control system for combinations of finger positions without locking channels.

FIG. 36 is a second embodiment of a control system for combinations of finger positions with lock channels.

FIG. 37 is a second embodiment of a control system for combinations of finger positions with lock channels.

In the prosthesis, the design of the finger consists of two phalanges: distal 1 and proximal 2. The fingers are attached to the body of the brush in the area of the base of the finger 3.

The phalanges are connected with each other and with the brush using rubber joints 4. At the ends of the rubber joints there are thickenings 5, with which the joint is fixed in the phalanges and the brush.

The bulges 5 can have different shapes: a circle, a rectangle, a triangle, a hexagon (Fig. 2).

The thickening 5, taking into account its deformation, should be such that, under a load close to maximum: destroying the phalanx and fastening the phalanx with the joint, the rubber joint is disconnected from the phalanx before they collapse. Immediately before reaching such a maximum load (90..95% of the maximum load that the phalanx can withstand without destruction), the joint disengages from the phalanx, i.e. the rubber joint is detached from the phalanx and hand, to prevent destruction of the fingers. The positive effect is that the joint with a thickening is a mechanical safety device that prevents mechanical destruction of the finger. The joints of the fingers are the most fragile part of the prosthesis and most often fail. The rubber joint increases the reliability of the prosthesis due to the fact that it prevents fracture during critical loads.

To reduce deformation across and twisting deformation, the joint can consist of two materials with different stiffness: soft material 7, 2 - more rigid and elastic material 6 or vice versa (Fig. 3).

Also, to reduce deformation across and twisting deformation, the joint has a structure as a thin-walled element with corrugated stiffeners or ribs in the form of honeycombs (Fig. 4).

To close the finger, the cable rod 9 is used. The cable rod passes through the brush and phalanxes of the finger along the channels 8. To close the finger, pull the cable 9, leaving the brush and mounted on the proximal phalanx (pos. 13 - place of cable attachment to the proximal phalanx) or on the distal phalanx (pos. 11 - the place of attachment of the cable to the distal phalanx). Opening the finger and returning to its original position occurs under the influence of elastic tension in bent rubber joints when releasing the cable.

Two design options for finger drives with cables can be implemented:

1 - One cable passes through both phalanges and is fixed in the distal phalanx;

2 - Each of the two phalanges in the finger has a separate phalanx cable (Fig. 6). The upper phalanx is connected by a cable 9, passing in the channel through the distal phalanx 1, with the base of the finger 12 and a brush. The distal phalanx is connected to another cable 9, which comes out of the brush and is attached to the distal phalanx.

In both finger designs, the cable rod can be attached to the finger through the spring 10. The spring imitates the elastic tension of the tendons in the finger and accumulates compression energy, which improves grip and prevents objects from slipping out of the hand. The spring can be either cylindrical in tension (pos. 10 in Figs. 5, 6), or in the form of a V-shaped elastic metal wire (pos. 10 in Fig. 7), for which the rod engages.

The surface of the upper phalanx and the lower part of the lower phalanx have rubber pads 14 and 15, silicone or other soft-elastic material, to prevent the object of capture from slipping. Also, the lower surface of the phalanges has a relief of 16.

Each phalanx consists of two parts 17 and 18. The two parts of the phalanx are interconnected by a bolt 19, press and fix the rubber joints. Places where the bolts are visible are closed with rubber pads 20. When the finger is overloaded and the phalanges are disengaged, the finger easily reassembles. To assemble the finger, you only need to unscrew the bolt and insert the rubber joint back into the phalanx. Also, thanks to this design, bolts and other structural elements are not visible from the outside of the finger.

Thumb rotation.

In all active prostheses, the position of the thumb is fixed in one position, there is no rotation and, therefore, active prostheses can only perform one wide cylindrical grip (Fig. 32). But the thumb is the most mobile and strongest finger out of five on the hand. Almost 80% of all motor skills of the hand are provided by the thumb. If a person loses his thumb, then you will not be able to perform almost 80% of all grips and manipulations with objects, and if you lose one of the other four fingers, then you will not be able to perform only about 20% of manipulations. This suggests that prostheses in which the thumb is fixed can perform 4 times less grips of different types compared to our prosthesis, which has the ability to rotate the thumb (Fig. 10) and perform clamping of the subterminal-lateral or pulp lateral opposition (Fig. 32).

The device and principle of operation of the thumb rotation system.

On the mechanical brush 21, in the region of the base of the thumb, there are two protrusions 26 through which the axis of rotation of the thumb 24 passes. The axis of rotation of the thumb is located at an angle α equal to from 0 ° to 80 ° relative to the position of the brush 25. A rotator is mounted on the protrusions 26 22 of the thumb, which rotates around the axis of rotation, leaning on the protrusions 26. On the rotator there is a thumb 23 of the prosthesis, which also rotates around the axis of rotation with the rotator. The rotator on the one hand has teeth 29 located radially around the axis of rotation of the thumb. On the contrary, on the brush in the area of the base of the thumb, also radially around the axis of rotation of the thumb, are the teeth 28. The spring 27 is always in a compressed state and presses the rotator of the thumb 22 to the teeth of the brush 29. Thus, the teeth of the rotator 29 are in contact with the teeth brushes 28 and are engaged with them, which leads to the fixation of the rotator with the thumb around the axis of rotation at an angle from 0 ° to 90 ° relative to the initial extreme position. In order to rotate the rotator with the thumb around the axis of rotation 24, it is necessary to apply force to the thumb along the direction of rotation: clockwise or counterclockwise 30. The level of force that must be applied to rotate the rotator depends on the stiffness of the spring 27, the quantity and the shape of the teeth 29 and 28. The stiffer the spring, the stronger it presses the rotator with the teeth to the teeth of the brush and the more force must be applied to disengage the gear mesh and rotate the rotator. When the force is applied to the thumb around the axis of rotation necessary to rotate the rotator with the thumb, then the rotator 22 is shifted to the side of the spring 27 and compresses it. The teeth of the rotator and the teeth of the brush diverge, the engagement disappears between them and the rotator rotates by one tooth, turning thumb 23 with it. After turning one tooth, the rotator returns to the teeth with the brush teeth under the action of a compressed spring. If the force applied to rotate the rotator continues to act on it, then the trip procedure is repeated and the rotator rotates by one clove. This will continue until the force ceases to act on the rotator with the thumb. In the rotator there is a channel through which the cable 9 passes, closing the thumb.

Due to the rotation of the thumb around the axis of rotation, it has an additional degree of freedom, which leads to an increase in the number of possible grips by four times compared with prostheses in which it is not possible to rotate the thumb relative to the hand. The prosthesis can perform wide grips, grips of flat objects and even the capture of long thin objects, such as a ballpoint pen for writing or a toothbrush. This design of rotation of the thumb allows you to rotate and lock the thumb in one motion without pressing the lock button or lock. This is very important for people with amputation paired on both hands and allows them to adjust the angle of rotation. Also, when capturing an object, when the thumb presses on the subject of gripping, the rotator will press against the teeth of the brush and increase the engagement force, which prevents involuntary rotation of the thumb.

Link cable locking device (3 options).

In traction prostheses, when pulling the pull ropes, the hand closes and remains in this position while the ropes are pulled. As soon as the tension of the cables is removed, the fingers will return to their original state. For example, the tension of the cables and the closing of the hand occurs when the hand is tilted in the wrist joint relative to the forearm, and the opening of the hand occurs when the hand returns to its original state (Fig. 14). The prosthesis can hold the object only while the hand is bent in the wrist joint, which limits the movement and manipulation of the object, because when moving in the wrist joint, the prosthesis opens and the object falls out.

In the prosthesis there is a mode of operation in which the hand closes when pulling the cable ropes, and when the cable tension is removed, the brush does not open, but remains in the closed position (Fig. 15). The principle of operation is that the prosthesis includes a locking device for rods, which allows the ropes to move freely in the direction from the fingers towards the forearm, which leads to the closing of the fingers, but does not allow the ropes to move in the opposite direction from the forearm to the fingers for their discoveries. Those. the brush can only close and maintain the position of the fingers in the closed state. The positive effect is that a person after closing the brush and grabbing the subject does not apply force to hold the subject. Also, after capturing an object, a person can expand the wrist in the wrist joint (lower image in Fig. 15) and manipulate the captured object by rotating and tilting the wrist in the wrist joint. In other traction prostheses, when the hand is extended, the fingers open, and the object falls out of the grip (upper image in Fig. 15). To capture and hold an object, it is necessary to constantly apply force and keep the hand bent in the wrist joint, which is very inconvenient and does not allow you to manipulate the object using the wrist joint.

Three design variants of the linkage locking device can be implemented, which include an element in which the cable is fixed and an element that fixes the cable in a predetermined position until it is unlocked.

The first option includes a cylindrical housing 40 (Fig. 16), which tapers at one end and includes a cone-shaped tip 33. A fixed support in the form of a washer 34 is installed or screwed into the casing. The spring 35 pushes away from the washer 34 and pushes the piston 37 toward 41 all the time. the conical end 33 of the cylindrical body 40. The piston 37 is a wedge-shaped cylinder, that is, the wall contracts from the center of the cylinder to the edge. The piston is made in the form of a hollow cylinder, the diameter of one end is equal to the diameter of the hole of the cylindrical body from the side of the conical tip and made with the possibility of movement in the hole, the other end abuts the washer, the middle part of the piston has a diametrical wedge-shaped thickening, a spring is installed between the washer and the thickening of the piston, A ball bearing 36 is radially mounted in the piston’s inner channel. A finger traction cable 9 passes through the center of the piston and the entire linkage locking device. The principle of operation is to then if you pull the cable in the direction 39 of the closing of the brush, the cable will freely pass through the locking device, and the brush will close. If you pull the cable in the opposite direction, in the opening direction of the brush 39, then the piston 37 after the cable 9 will move towards 41 of the tapering end 33 of the housing 40. The walls of the tapering end 33 of the housing 40 will press on the ball bearings 36, which in turn will compress cable 9, block and prevent it from moving in the direction of brush opening 41. The stronger the force with which the cable is pulled, the stronger the cable-pull will be compressed and blocked by ball bearings. To unlock the draft cable, it is necessary to move the piston 37 to the side opposite from the tapering body, i.e. in the direction of closing 39. This can be done in two ways:

- pull the cable in the direction of closing the brush 39;

- by pressing on the part of the piston 37, protruding outside the housing of the locking device, from the tapering side of the housing 33 towards the opening of the brush 41. To push the piston, use the bar, lever 43. The devices for locking the cable rods are located in the brush or forearm. If the prosthesis uses an automatically adaptable gripper system (described in RF patent No. 160806 “Hand prosthesis”), then the cable-locking devices can be located both after the automatically adapted gripper system (Fig. 18) and before the automatically adapted gripper system ( Fig. 19). Where an automatically adaptable gripper system connects the first and second, third and fourth fingers through the pulleys in pairs. Pulleys are connected by a barbell. This design is very simple and reliable. The wedge-shaped shape and principle of operation of the housing and piston of the linkage locking device create a reliable and strong locking of the cable with very small dimensions of the locking device. The locking device is silent and does not create the sounds of mechanical shocks, clicks, the sounds of friction and squeaking. Ball bearings 36 prevent the traction cable from wearing off from friction and biting, and also help to unlock the cable with minimal force to unlock.

The second embodiment of the locking device (Fig. 21) consists of a rail with teeth 44 on which ropes of rods 9 are fixed. The length of the rail is equal to the length of the rope, which must be pulled out to completely close the finger. A ratchet 45, which is meshed with the teeth of the rack, is installed above the rack with teeth. When the brush is closed, the cable pulls the bar with teeth 44 in the direction 46 of the wrist joint 47. Due to the inclination of the teeth of the bar and ratchet, the ratchet tooth rises up when the tooth of the bar goes through and does not interfere with the movement of the bar in direction 46 of the wrist joint during closing of the wrist. While the ratchet 45 is engaged with the teeth of the rack 44, it does not allow the cable rod 9 with the rod 44 to move in the direction of opening of the fingers and blocks the cable rod. To unlock the cable and open the brush, you must raise the ratchet 45 to disengage the teeth of the rack 44 and the ratchet. Then the cable-rod with the rail will move freely in the direction of the opening of the brush. To raise the ratchet and unlock the traction cable, it is necessary that the lever 49 rotates, press the ratchet and lift it.

The third design option is a simplified version of the first design and is a wedge 50, pressed by a spring 51 to the housing of the brush 21. The wedge allows the cable-pull to move freely in one direction when closing the brush. With the movement of the cable-traction during the opening of the brush, the wedge 50 presses the cable traction 9 to the housing 21 and blocks it.

To unlock the brush and open it in all three variants of the design of the cable-traction blocking device, it is necessary to turn the brush upwards in the wrist joint by an angle from 20 ° to 90 ° relative to the initial position (Fig. 24) or tilt to the right, to the left of an angle of 20 ° to 70 ° relative to the forearm. The angle at which the brush opens is adjusted using the controller (Fig. 16 and Fig. 26).

Forearm and wrist joint.

The forearm of the prosthesis is the part of the prosthesis that is attached to the forearm of the arm and consists of three separate segments / parts 52. If necessary, the middle segment can be removed and then the forearm will consist of two segments: distal and proximal. A tube 53 of silicone or another flexible polymer having an elastic tensile strain passes through each segment, on both sides. One end of the flexible tube is attached to the distal segment. The other end of the tube is attached to the brush. To fix the tube have a thickening at the ends. The tubes are also fixed by screws 54. The connection using the flexible tube of the hand and the forearm segment adjacent to the hand forms a movable wrist joint 47.

In the extreme segment is the mechanism 55 of the tension of the cable rods and the roller 56 of the mechanism of tension of the cables. Traction cables 9, which cover the brush, are mounted on the slider of the traction tension mechanism 55, pass through all segments of the forearm 52 and enter the brush 21. The traction tension mechanism slider 57 has a threaded hole into which screw 58 is screwed. The screw is connected to the mechanism roller cable tension 56. When turning the roller 56, the screw is screwed in or out of the slider, as a result of which the slider moves forward or backward and pulls or loosens the cable tension.

On the sides of each segment 52 there are slots for belts 59. Belts 60 are fixed in these slots, with the help of which the forearm of the prosthesis is fixed on the forearm of the human arm 61.

In the segment that adjoins the hand, it connects to it and forms a wrist joint 47, the brush unlocking angle adjuster 62 is installed on top. The angle of rotation of the brush up or left and right, at which the regulator 62 acts on the locking device of the pull ropes 63, the cable fixation is removed, and the brush opens, the angle of the necessary rotation for the impact of the plate of the regulator 62 on the lock 63 is adjusted using the position of the unlock controller. The further the regulator is pulled out of the segment and the closer it is to the brush, the smaller the angle of rotation of the brush relative to the forearm is necessary in order to unlock the brush and open it.

Compared to a solid forearm or a stump sleeve, other prostheses, which have only one degree of freedom in the wrist joint, severely constrain and restrict hand movements, the forearm of this design has three degrees of freedom in the wrist joint relative to the forearm and one degree of freedom in the forearm relative to the shoulder, which completely repeats the functionality and mobility of the wrist joint and forearm of the living arm, which increases the functionality of the prosthesis and the convenience of its use. Since the wrist joint of the prosthesis is a combination of the hand and forearm using a flexible tube, the hand can move relative to the forearm in three planes: 1 - tilts up and down; 2 - turns to the right and left; 2 - rotation of pronation and supination (possible directions of movement are shown by arrows in Fig. 26). This is possible due to the elastic extension of the tube. When the pronation and supination brushes are rotated, the radial bones of the forearm also perform pronation and supination. One-piece designs of the forearm and stump sleeve do not allow pronation and supination. This design of the forearm, due to the flexible tubes passing through the segments, allows pronation and supination of the forearm of the hand due to the fact that each segment of the forearm of the prosthesis can move along the path of pronation and supination relative to the adjacent segment. In this case, the forearm of the prosthesis does not lose traction with the forearm of the hand and the prosthesis is securely fixed to the hand due to the fact that each segment of the forearm of the prosthesis has its own belt, fixed in the cutouts of the segment with which it is fixed on the forearm of the hand. Also, a forearm consisting of segments is easier to adjust to the individual sizes of the forearm of a person’s hands during manufacture and repair in the future during operation.

Teflon tubes.

Cable rods pass from the forearm to the fingers of the prosthesis through the channels in the brush of the prosthesis. Due to the large length of the channels and their complex and curved trajectory, a large surface area of contact between the ropes of the rods with the brush of the prosthesis appears, which leads to a high coefficient of sliding friction, loss of efficiency, rapid wear of parts of the brush of the prosthesis and ropes of rods from friction. Resistance to human effort also appears when closing the hand. To reduce the coefficient of friction between the traction cable and the surface of the channel through which the traction cable passes, PTFE (polytetrafluoroethylene, Teflon or PTFE) tubes 75 pass through the prosthesis brush channels 8 over the entire length of the traction cable. Traction cables 9 pass inside the PTFE (Teflon) tubes 75. Thus, tie rods have contact only with PTFE (polytetrafluoroethylene, Teflon or fluoroplastic) tubes.

PTFE (polytetrafluoroethylene, teflon or fluoroplastic) tubes have a low coefficient of sliding friction, which leads to a decrease in the friction of the tie rods with the surface of the channels, an increase in efficiency and a decrease in the wear of the tie rods and the prosthesis brush due to friction.

Control system for the combination of the position of the fingers (gestures).

All active prostheses can perform only one grip and a wide cylindrical gesture (Fig. 32a) when all fingers are closed simultaneously. There is no way to select and execute one gripe from a set of grips / gestures or close several fingers out of five.

This prosthesis implements a system of grips / gestures. The main grips / gestures that can be implemented:

- The index finger (Fig. 32b). With this grip, all fingers are closed except the index finger. This gesture is necessary for pressing buttons and working with the keyboard of a personal computer, the touch screen of a smartphone and tablet. Also, this grip "index finger" allows you to perform centered grips;

- Two-fingered or three-fingered pinch (Fig. 32b, 32g, 32d). With this grip, the thumb closes with the index finger or thumb, index and middle.

The principle of the grips / gestures system is to block the closure of individual fingers: one or more. You can mechanically program any gesture by blocking different combinations of fingers. Finger closure occurs when the cables are pulled. To perform a gesture, it is necessary to block some cables and not allow them to move and close their fingers, while others do not block and let the cables close their fingers.

Two design options for the gesture system can be implemented.

The first design is the locking of the ropes of rods by means of a device for blocking rods (Fig. 16), which is installed so that the locking device (Fig. 16) with the piston 37 not pressed, blocks and stops the rope of the rod during closing of the finger. Link lock device for the gesture system is installed in the brush in front of the adaptive gripping system 65. That is, traction cable when moving from the finger to the forearm, first passes through the locking device of the gesture system 64, then the adaptive capture system 65, then through the locking system 63.

Gesture / grip “exposed index finger” is carried out using the rod lock device 64, which blocks the movement of the rod cable 9 of the index finger 68 during the closing of the brush. Thus, when the brush is closed, all fingers except the index finger are closed, and a gesture / grip is obtained: the index finger is 68. To switch the grip on and off, the exposed index finger uses the button / lever 67, which presses the lock piston 37 and disengages the grip, or releases the piston and engages the grip of the exposed index finger.

Gesture / grip “pinch” is carried out similarly to the “exposed index finger” grip, only the locking device blocks the cables of the little finger, the ring finger and the middle finger 69 with a double-fingered pinch. To turn the grip on and off, use the button / lever 70, which presses the pistons 37 of the device locks and disables the tong, or releases the pistons and turns on the tongs.

The second design - with the help of 9 anchors fixed on ropes-rods, a polyhedron, for example, a hexagon 71, and a plate 72 with cutouts 73, the ropes-rods will be locked or unlocked when a gesture is selected. When grips / gestures are disabled, all fingers close and are not locked. Therefore, the ropes with fixed anchors 71 move in the direction shown by the arrows in FIG. 35 is free in the channels of the gesture / grip plate 72, nothing blocks them.

Gesture / grip "pinch" (Fig. 32b) is carried out by blocking the anchors and ropes-rods of the little finger, the ring finger and, with a double-fingered pinch, middle finger (Fig. 36). In the grip position “pinch” there are no channels in the plate 72, along which the anchors of the little finger, the ring finger and, with the double-fingered pinch, move the middle finger, and these fingers are blocked. Only the thumb, index finger and, with a three-fingered pinch, the middle finger can be closed.

Gesture / grip "exposed index finger" (Fig. 32B) is carried out by locking the anchor and the cable-pull of the index finger (Fig. 37). There are no channels in the plate along which the index finger anchor moves, and the index finger is blocked. All other fingers except the index finger close.

When connecting the channels of the three grips / gestures (pinch (Fig. 36-2), the exposed index finger (Fig. 37-2) and the free closing of all fingers (Fig. 35-2),) in one plate of grips / gestures, we get a plate three grips / gestures (Fig. 33 pos. 72). In the initial position of the plate, the prosthesis includes a grip / gesture “free closing of all fingers”, when the plate is shifted to the right from the initial position, the grip / gesture “exposed index finger” is turned on, and when shifted to the left of the initial position, the grip / gesture “pinch” is turned on. Thus, by shifting the plate, the user selects a gripper / gesture. The displacement of the plate should be carried out both when turning the brush to the right and left in the wrist joint, and manually with the second hand. The plate is fixed in the selected position, and to change the position you need to apply a certain force.

Choosing a grasp / gesture, the user of the prosthesis can perform much more actions than an active prosthesis with one coverage. With the gesture system, the functionality of the active prosthesis increases to the level of complex electromechanical prostheses with an external energy source.

Claims (16)

1. A prosthetic arm for patients with a degree of amputation from fingers to the forearm, including a prosthetic hand, including a cable and pulley system, a prosthetic forearm and a wrist prosthesis connecting the wrist prosthesis with a forearm prosthesis, characterized in that the wrist prosthesis is formed by connecting the prosthetic joint hands and prosthesis of the forearm by means of at least two flexible tubes with thickenings at the ends, each of which is fixed at one end in the prosthesis of the hand, the other in the prosthesis of the forearm, forearm soda neighs the distal and proximal segments, connected by two flexible tubes fixed at both ends in the segments to be connected, the hand lock device is installed in the hand, the hand prosthesis traction cable tension mechanism and the hand unlock angle adjuster, which is a plate fixed to the arm, are installed in the proximal segment of the forearm the surface of the proximal segment and made with the possibility of extension beyond the segment and the impact on the device blocking the brush installed in the prosthesis of the hand p ki. 2. The prosthetic arm according to claim 1, characterized in that the tubes are attached to the segments of the forearm and to the prosthetic hand using screws. 3. The prosthetic arm according to claim 1, characterized in that each segment of the forearm has a slot for the belt. 4. A hand prosthesis for a hand prosthesis according to claim 1, comprising a hand lock device and a mechanical hand containing a metacarpus, artificial fingers connected to the metacarpus by joints, formed by phalanges connected by joints with channels through which cables are stretched, the ends of which are fixed to the distal phalanges and at the ends of pulleys connected by a cable to a cable tensioning unit, characterized in that the joint connecting adjacent phalanxes of the fingers and phalanx to the metacarpus is an elongated elastic el A dent with thickenings at the ends, on the metacarpal in the region of the base of the thumb, a recess is made with coaxially mounted protrusions in which the rotator is mounted to form the rotation axis of the thumb mounted on the rotator, while on the one hand the rotator contains teeth located radially around the rotation axis of the thumb finger, a spring is installed on one of the protrusions, and teeth are located around the other protrusion on the recess wall, which, when the rotator is installed in the recess, mesh with the teeth on the rotator, on the metacarpus between Alzen node and tension cables or tension wires between the node and the proximal part of the metacarpal posted control system combination of finger positions comprising at least one thrust finger rope lock device configured to lock the cable. 5. The prosthetic hand according to claim 4, characterized in that the ropes of the rods are laid inside the Teflon tubes placed inside the channels for the ropes. 6. The prosthetic hand according to claim 4, characterized in that the phalanx of the finger is made of two parts, between which a thickened area of the joint is located and which are connected to each other by means of a bolt. 7. The prosthesis of the hand according to claim 4, characterized in that the surface of the distal phalanx and part of the proximal phalanx facing the palm have lining made of soft elastic material. 8. The prosthesis of a hand according to claim 7, characterized in that a part of the surface of the phalanx facing the palm is made in relief. 9. The wrist joint prosthesis for a hand prosthesis according to claim 1, characterized in that it includes at least two flexible tubes with thickenings at the ends, each of which is screwed to one end in the wrist prosthesis and the other in the forearm prosthesis. 10. The device for locking the ropes of the fingers of the fingers of the prosthesis of the hand according to claim 4, characterized in that it includes a hollow cylindrical body with a conical tip, a washer fixed to the body, a piston in the form of a hollow cylinder is installed between the conical tip and the washer, the diameter of one end is equal to the diameter of the hole of the cylindrical body from the side of the conical tip and made with the possibility of movement in the hole of the body, the other end abuts the washer, the middle part of the piston has a diametrical wedge-shaped thickening A spring is installed between the washer and the piston thickening, a ball bearing is radially mounted in the inner channel of the piston, the cable passes through the channel formed by the body cavity, the hole in the washer and the piston cavity. 11. The device for locking the cables of the finger rods according to claim 10, characterized in that the piston in the part facing the outside of the conical tip of the housing is connected to a lever-button. 12. The device for locking the ropes of the fingers of the fingers of the prosthesis of the hand according to claim 4, including a toothed rack on which ropes of rods are fixed on both sides, a ratchet is installed above the rack, which is engaged with the teeth of the rack. 13. The device for locking the cables of the finger rods according to claim 12, characterized in that it includes a lever mounted above the ratchet, made with the possibility of lowering and raising the ratchet. 14. The device for locking the ropes of the fingers of the fingers of the prosthesis of the hand according to claim 4, characterized in that it includes a wedge connected to a spring fixed in the body of the brush, while the cable passes between the wedge and the body of the hand. 15. The control system for the combination of the position of the fingers of the prosthesis of a hand according to claim 4, characterized in that it includes three locking devices for locking the middle finger, ring finger and little finger connected by a lever, connected to the fingers by means of cables and connected by cables to pulleys with which by cables a locking device for the index finger is connected, two pulleys combining in pairs the cables from the index and middle fingers, the ring finger and little finger, are connected by a barbell and connected by cables to a locking device integrated by means of a lever with a thumb locking device connected to the thumb by a cable. 16. The control system for the combination of the position of the fingers of the prosthetic hand according to claim 4, characterized in that it includes an elongated plate with transverse channels through which the cables pass from the fingers to the pulleys, a polyhedron is fixed to each cable in the channel area, while the channels have branches, the dimensions of which correspond to the dimensions of the polyhedron, and the plate is made with the possibility of displacement along a straight, perpendicular axis of the channel, and at least one device for locking the cables of the rods of the fingers, made with the possibility of fixing wire rope.

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