Under-actuated prosthetic finger device with multiple grasping modes

Abstract

The invention relates to the technical field of rehabilitation medical instruments, in particular to an underactuated prosthetic finger device with multiple grasping modes, which comprises a first knuckle, a second knuckle, a third knuckle and a connecting rod structure, the first knuckle, the second knuckle and the third knuckle are connected with one another through the connecting rod structure, a silica gel block is mounted at the bottom end of the second knuckle, and the silica gel block is mounted at the bottom end of the second knuckle. The finger further comprises a clamping mechanism and a taking and water absorbing mechanism, the clamping mechanism is arranged on the first knuckle, and the first knuckle is detachably provided with a rubber mounting block through the clamping mechanism. According to the prosthetic finger, sheet-shaped objects and small pill-shaped objects on a plane can be conveniently and stably taken, the taking stability of objects with water stains on the surfaces can be effectively improved, in addition, when objects prone to deformation or fragile are taken, the objects can be conveniently taken, and the objects can be conveniently taken. And the risk that the object slides down due to small force applied during grabbing is obviously reduced, so that the taking stability of the object which is easy to deform or fragile is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of rehabilitation medical devices, and particularly relates to an underactuated prosthetic finger device with multiple grasping methods. Background Art

[0002] A prosthetic finger device refers to an artificial device used to replace a missing or damaged finger of the human body. Its main purpose is to restore the appearance and function of the finger, and help the patient regain basic hand operation capabilities, such as grasping and pinching. According to different driving methods, prosthetic finger devices can be divided into passive type, semi-active type and active type. Passive prosthetic fingers mainly rely on external forces (such as the healthy hand) to assist movement. The semi-active type realizes a certain degree of autonomous movement through elastic elements or energy storage mechanisms. The active type is equipped with a power source (such as a motor) and can actively drive the finger to move. Among them, an underactuated prosthetic finger device refers to an active prosthetic finger device in which the number of drivers is less than the number of driven joints.

[0003] After retrieval, a Chinese patent with the patent publication number CN210077958U discloses a flexible prosthetic finger. This patent makes the finger generate flexibility when grasping an object by setting a shaft sleeve and an elastic connecting piece on the connecting rotating shaft of the upper joint and the lower joint, so as to better simulate the grasping performance of a real human hand. However, when in use, it is not convenient to grasp sheet-shaped objects and small pill-shaped objects on a plane. In addition, during the use of existing prosthetic fingers, when grasping easily deformable and fragile objects, since too much force cannot be applied during grasping, it is easy to slip during the grasping process. At the same time, if there is water on the surface of the object to be grasped, it will reduce the friction between the finger and the object, which will also easily cause the prosthetic finger to slip during the grasping process, and the practicability is not good. Summary of the Invention

[0004] The purpose of the present invention is to solve the problem that existing prosthetic finger devices have difficulty in grasping or poor grasping effect when performing taking operations on some objects, and to propose an underactuated prosthetic finger device with multiple grasping methods.

[0005] To achieve the above purpose, the present invention adopts the following technical solution: An underactuated prosthetic finger device with multiple grasping methods, including a first phalanx, a second phalanx, a third phalanx and a link structure. The first phalanx, the second phalanx and the third phalanx are all connected to each other through the link structure. A silica gel block is installed at the bottom of the second phalanx. It further includes: A clamping mechanism and a picking and absorbing mechanism. The clamping mechanism is arranged on the first finger joint. The first finger joint is detachably installed with a rubber mounting block through the clamping mechanism. The clamping mechanism is used to realize the convenient replacement of the rubber mounting block. The picking and absorbing mechanism is arranged on the rubber mounting block and is used to enable the prosthetic finger to stably pick up sheet-shaped objects and small pill-shaped objects and extract the water marks on the surface of the picked-up objects. A friction enhancement mechanism is arranged on the second finger joint and is used to enhance the friction between the prosthetic finger and the picked-up object.

[0006] Preferably, the clamping mechanism includes an embedding groove and an embedding block. The embedding groove is opened at one end of the third finger joint away from the second finger joint. A rotating component is installed on the embedding block, and the embedding block is connected to the rubber mounting block through the rotating component. The embedding block is inserted into the embedding groove, and grooves are opened on both sides of the embedding block. A first spring is installed in the grooves, and a triangular clamping block is connected to the grooves through the first spring. Sliding grooves are opened on both sides of the grooves. Two sliders are symmetrically installed on one side of the triangular clamping block facing the first spring, and the triangular clamping block is slidably connected in the sliding grooves through the sliders. Two pushing grooves are opened on the inner wall of the embedding groove, and the positions of the two pushing grooves correspond to the positions of the two grooves. The triangular clamping block is located in the pushing grooves. A pushing component is arranged in the third finger joint and the two pushing grooves to apply a thrust to the triangular clamping block.

[0007] Preferably, the rotating component includes an installation cavity. The installation cavity is opened at one end of the embedding block facing the rubber mounting block, and a motor is installed in the installation cavity. A transmission disk is installed at the output end of the motor, and the motor is connected to the rubber mounting block through the transmission disk. The outer side wall of the transmission disk is in contact with the inner wall of the installation cavity.

[0008] Preferably, the pushing component includes two pressing plates and two force application grooves. The two force application grooves are opened inside the third finger joint, and through holes are provided on the outer side of both force application grooves. The radius of the through holes is smaller than the radius of the force application grooves, and a pressing block is arranged in the through holes. A limiting block is installed on the outer wall of the pressing block, and the pressing block is slidably connected in the force application grooves through the limiting block. A connecting rod and a second spring are installed at the inner end of the pressing block facing inward, and the pressing block is connected to the inner wall of the force application groove through the second spring. The inner end of the connecting rod penetrates through the inner wall of the force application groove and is fixedly connected to the pressing plate. The pressing plate is slidably connected in the pushing groove. The height of the pushing groove is greater than the height of the groove, and the height of the pushing groove corresponds to the height of the pressing plate.

[0009] Preferably, the water-absorbing and picking mechanism includes two silicone sheets and a plurality of micro-suction cups. The plurality of micro-suction cups are respectively fixedly embedded at the top end of the rubber mounting block and at one end away from the third phalanx. Connecting plates are installed at the top ends of the two silicone sheets, and the two silicone sheets are symmetrically installed on the rubber mounting block through the connecting plates. There is a separation component on the rubber mounting block, and the rubber mounting block is connected with two silicone strips through the separation component. The two silicone strips are in contact with each other, and the outer sides of the two silicone strips are respectively in contact with the two silicone sheets. The silicone sheets and the silicone strips are both located below the rubber mounting block, and a plurality of branch grooves are opened at the bottom ends of the silicone sheets and the silicone strips. The positions of the plurality of branch grooves on the silicone sheets and the silicone strips correspond to each other. A plurality of main grooves are opened at the bottom end of the silicone strip. A water-absorbing component is arranged on the rubber mounting block, the silicone strip and the main groove for sucking the water liquid in the main groove and the branch groove.

[0010] Preferably, the main groove and the branch groove are arranged in a cross-shaped intersection, and the width of the main groove is greater than the width of the branch groove.

[0011] Preferably, the separation component includes two strip-shaped grooves. The two strip-shaped grooves are both opened at the bottom end of the rubber mounting block, and a first electric telescopic rod is installed inside each of the two strip-shaped grooves. The output ends of the two first electric telescopic rods face in opposite directions, and a transmission plate is installed on each of them. The bottom ends of the two transmission plates are respectively fixedly connected to the top ends of the two silicone strips, and the two transmission plates are located close to one side where the two silicone strips are in contact. Strip-shaped plates are installed at the opposite ends of the two transmission plates, and the two strip-shaped plates are respectively installed at the top ends of the two silicone strips.

[0012] Preferably, the water-absorbing component includes a square groove, an L-shaped connecting block and two through grooves. The square groove is opened at the bottom end of the rubber mounting block, and a water tank is installed on the inner side wall of the square groove. The L-shaped connecting block is installed at the bottom end of the rubber mounting block, and a second electric telescopic rod is installed on the L-shaped connecting block. The output end of the second electric telescopic rod penetrates through the bottom end of the water tank and is fixedly connected to a piston. The piston is hermetically slidably connected in the water tank; The two through grooves are respectively opened at one end of the two silicone strips. A plurality of square tubes are installed on the inner bottom wall of the through groove. A plurality of connecting tubes are installed at the bottom end of the square tube. The bottom ends of the plurality of connecting tubes penetrate through the inner bottom wall of the through groove and are located in the main groove. A second one-way tube and a plurality of first one-way tubes are installed at the top end of the water tank. The end of the second one-way tube away from the water tank is located in the gap between the rubber mounting block and the silicone strip. The ends of the plurality of first one-way tubes away from the water tank penetrate through the top walls of the two silicone strips and are respectively connected to the plurality of square tubes. The first one-way tube, the second one-way tube and the connecting tube are all flexible hoses.

[0013] Preferably, the friction enhancement mechanism comprises a mounting groove and a connecting belt, the mounting groove is provided at the top of the second knuckle, a micro air pump is installed in the mounting groove, an L-shaped fixing plate is installed at the end of the second knuckle away from the first knuckle, a yielding groove is provided on the L-shaped fixing plate, and two support plates are symmetrically installed on the bottom end of the L-shaped fixing plate, the two support plates are connected to a rotating shaft for common rotation, and a strip air bag is fixedly wound around the rotating shaft; A connecting hose is installed at the output end of the micro air pump, and the end of the connecting hose away from the micro air pump passes through the inner wall of the installation groove and is connected to the strip air bag through the give way groove. One end of the connecting belt is fixedly connected to the top of the strip air bag near the edge, and a plurality of fixing strips are fixedly connected to the connecting belt. A second magnetic plate is installed on the side of the connecting belt away from the second finger joint, and the sides of the connecting belt and the fixing strip facing the second finger joint are in contact with the strip air bag. A first magnetic plate is installed at the bottom end of the L-shaped fixed plate, and two volute springs are installed on the rotating shaft, and the rotating shaft is connected to the L-shaped fixed plate through the volute spring.

[0014] Preferably, a porous plate is detachably mounted at the top opening of the mounting groove, and the length of the connecting hose corresponds to the length of the strip airbag.

[0015] Compared with the prior art, the advantages of the present invention are: 1. The present invention, through the provision of a water-absorbing mechanism, can not only utilize the adsorption of a micro suction cup and the clamping of a silicone strip to enable the prosthetic finger to conveniently and stably grasp sheet-like objects and small pill-like objects on a plane, but can also utilize the opening of grooves at the bottom of the silicone sheet and the silicone strip and the extraction of water marks on the surface of the object to be grasped to increase the friction between the silicone sheet and the silicone strip and the object, and effectively reduce the interference of water stains on the grasping operation of the prosthetic finger, thereby effectively improving the grasping stability of objects with water marks on the surface.

[0016] 2. The present invention, through the provision of a friction enhancing mechanism, can utilize the pulling out and expansion of the strip airbag to fill the gap between the prosthetic finger and the object when picking up easily deformable or fragile objects, thereby increasing the contact area between the prosthetic finger and the object, that is, effectively increasing the friction between the prosthetic finger and the object, and further significantly reducing the risk of the object slipping due to small force applied during grasping, that is, effectively improving the stability of picking up easily deformable or fragile objects.

[0017] 3. The present invention, through the setting of the snap-fit ​​mechanism, can use the pressing of the pressing block to quickly and conveniently complete the replacement of the fingertip part of the prosthetic finger (i.e., the rubber mounting block and the various mechanisms thereon) when the fingertip part of the prosthetic finger is damaged, thereby reducing the cost of replacement of damaged parts, and the replacement operation can be completed with one hand. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the overall structure of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention; Figure 2 Schematic diagram of the disassembly of the second phalanx and the porous plate structure of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention; Figure 3 Schematic diagram of the micro air pump and the silicone block structure of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention; Figure 4 Schematic diagram of the bar-shaped airbag and the scroll spring structure of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention; Figure 5 Schematic diagram of the rubber mounting block and the micro air pump of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention; Figure 6 Cross-sectional view of the rubber mounting block, the silicone sheet and the embedded block structure of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention; Figure 7 is Figure 6 Enlarged view of the structure at A in Figure 8 Schematic diagram of the disassembly of the rubber mounting block, the silicone sheet and the embedded block structure of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention; Figure 9 Schematic diagram of the water tank, the first one-way tube and the second one-way structure of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention; Figure 10 Cross-sectional view of the rubber mounting block structure of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention; Figure 11 Schematic diagram of the bottom structure of the silicone sheet and the silicone strip of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention; Figure 12 Cross-sectional view of the silicone strip structure of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention; Figure 13 Cross-sectional view of the water tank and the piston structure of an underactuated prosthetic finger device with multiple grasping methods proposed by the present invention.

[0019] In the figure: 1. First finger joint; 2. Second finger joint; 3. Third finger joint; 4. Linkage structure; 5. Rubber mounting block; 6. Silicone sheet; 7. Mounting groove; 8. Perforated plate; 9. Micro air pump; 10. Silicone block; 11. L-shaped fixing plate; 12. Strip-shaped airbag; 13. Rotating shaft; 14. Volute spring; 15. First magnetic plate; 16. Second magnetic plate; 17. Connecting belt; 18. Fixed strip; 19. Micro suction cup; 20. Silicone strip; 21. Embedded block; 22. Motor; 23. Driving disc; 24. Triangular clamping block; 25. Pressing block; 26. Extrusion plate; 27. First electric telescopic rod; 28. Driving plate; 29. Water tank; 30. First one-way tube; 31. Second one-way tube; 32. Main groove; 33. Branch groove; 34. Connecting tube; 35. Square tube; 36. Second electric telescopic rod; 37. Piston. Detailed implementation mode

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0021] Refer to Figures 1 to 8 , an underactuated prosthetic finger device with multiple grasping methods, including a first finger joint 1, a second finger joint 2, a third finger joint 3 and a linkage structure 4. The first finger joint 1, the second finger joint 2 and the third finger joint 3 are all connected to each other through the linkage structure 4. The linkage structure 4 is used to enable the first finger joint 1, the second finger joint 2 and the third finger joint 3 to cooperate and achieve bending and grasping behaviors. And the linkage structure 4 is a prior art, and its specific structural design will not be elaborated here. A clamping mechanism is provided on the first finger joint 1, and a rubber mounting block 5 is detachably mounted on the first finger joint 1 through the clamping mechanism. The clamping mechanism is used to realize the convenient replacement of the rubber mounting block 5. A silicone block 10 is installed at the bottom end of the second finger joint 2. The clamping mechanism includes an embedding groove and an embedding block 21. The embedding groove is opened at one end of the third finger joint 3 away from the second finger joint 2. A rotating component is installed on the embedding block 21, and the embedding block 21 is connected to the rubber mounting block 5 through the rotating component. The embedding block 21 is inserted into the embedding groove, and grooves are opened on both sides of the embedding block 21. A first spring is installed in the grooves, and the grooves are connected to a triangular clamping block 24 through the first spring. Sliding grooves are opened on both sides of the grooves. Two sliders are symmetrically installed on one side of the triangular clamping block 24 facing the first spring, and the triangular clamping block 24 is slidably connected in the sliding grooves through the sliders. Two pushing grooves are opened on the inner wall of the embedding groove, and the positions of the two pushing grooves correspond to the positions of the two grooves. The triangular clamping block 24 is located in the pushing grooves. A pushing component is arranged in the third finger joint 3 and the two pushing grooves, and is used to apply a thrust to the triangular clamping block 24.

[0022] Refer to Figures 6 to 8The rotating assembly includes a mounting cavity, which is opened at one end of the embedding block 21 facing the rubber mounting block 5, and a motor 22 is installed in the mounting cavity. A transmission disc 23 is installed at the output end of the motor 22, and the motor 22 is connected to the rubber mounting block 5 through the transmission disc 23. The outer wall of the transmission disc 23 is in contact with the inner wall of the mounting cavity. This contact setting helps to reduce the torque borne by the motor 22 during operation, thereby reducing the burden of the motor 22 and extending the service life of the motor 22. The pushing assembly includes two extrusion plates 26 and two force application grooves, and the two force application grooves are opened inside the third finger joint 3 , and both force-applying grooves are penetrated with a through opening on the outward side, the through opening radius is smaller than the radius of the force-applying groove, and a pressing block 25 is arranged in the through opening, a limit block is installed on the outer wall of the pressing block 25, and the pressing block 25 is slidably connected in the force-applying groove through the limit block, a connecting rod and a second spring are installed at the inward end of the pressing block 25, and the pressing block 25 is connected to the inner wall of the force-applying groove through the second spring, the inward end of the connecting rod passes through the inner wall of the force-applying groove, and is fixedly connected with an extrusion plate 26, the extrusion plate 26 is slidably connected in the advancement groove, the advancement groove height is greater than the groove height, and the advancement groove height corresponds to the extrusion plate 26 height.

[0023] Reference Figure 1 as well as Figures 5 to 12 , a water-taking mechanism is provided on the rubber mounting block 5, which is used to enable the prosthetic finger to stably take sheet-like objects and small pill-like objects and to extract water marks on the surface of the taken objects. The water-taking mechanism includes two silicone sheets 6 and a plurality of micro suction cups 19. The plurality of micro suction cups 19 are respectively fixedly embedded in the top of the rubber mounting block 5 and the end away from the third finger joint 3. A connecting plate is installed on the top of the two silicone sheets 6, and the two silicone sheets 6 are symmetrically installed on the rubber mounting block 5 through the connecting plate. A separation component is provided on the rubber mounting block 5, and the rubber mounting block 5 is connected to two silicone strips 20 through the separation component. The two silicone strips 20 are in contact with each other, and the two silicone strips 20 are respectively connected to the two silicone strips 20 on their outward sides. The two silicone strips 20 are in contact with each other, and the separation component is used to separate the two silicone strips 20 from each other. The silicone strip 6 and the silicone strip 20 are both located below the rubber mounting block 5. The separation component includes two strip grooves, and the two strip grooves are both opened at the bottom end of the rubber mounting block 5. The first electric telescopic rods 27 are installed inside the two strip grooves. The output ends of the two first electric telescopic rods 27 face oppositely and are both installed with transmission plates 28. The bottom ends of the two transmission plates 28 are respectively fixedly connected to the top ends of the two silicone strips 20, and the two transmission plates 28 are located close to the side where the two silicone strips 20 are in contact. The opposite ends of the two transmission plates 28 are installed with strip plates, and the two strip plates are respectively installed on the top ends of the two silicone strips 20.

[0024] Reference Figures 8 to 13, multiple support grooves 33 are provided at the bottom ends of the silica gel sheet 6 and the silica gel strip 20. The positions of the multiple support grooves 33 on the silica gel sheet 6 and the silica gel strip 20 correspond to each other. Multiple main grooves 32 are provided at the bottom end of the silica gel strip 20. The main grooves 32 and the support grooves 33 are arranged in a cross shape, and the width of the main grooves 32 is greater than the width of the support grooves 33. A water absorption component is provided on the rubber mounting block 5, the silica gel strip 20 and the main grooves 32 for absorbing the water liquid in the main grooves 32 and the support grooves 33. The water absorption component includes a square groove, an L-shaped connecting block and two through grooves. The square groove is provided at the bottom end of the rubber mounting block 5, and a water tank 29 is installed on the inner side wall of the square groove. The L-shaped connecting block is installed at the bottom end of the rubber mounting block 5, and a second electric telescopic rod 36 is installed on the L-shaped connecting block. The output end of the second electric telescopic rod 36 penetrates through the bottom end of the water tank 29 and is fixedly connected with a piston 37. The piston 37 is hermetically and slidably connected in the water tank 29. The two through grooves are respectively provided at one end of the two silica gel strips 20. A plurality of square tubes 35 are installed on the inner bottom wall of the through grooves. A plurality of connecting tubes 34 are installed at the bottom ends of the square tubes 35. The bottom ends of the plurality of connecting tubes 34 all penetrate through the inner bottom wall of the through grooves and are located in the main grooves 32. The relatively large width setting of the main grooves 32 facilitates the installation of the connecting tubes 34. A second one-way tube 31 and a plurality of first one-way tubes 30 are installed at the top end of the water tank 29. The end of the second one-way tube 31 away from the water tank 29 is located in the gap between the rubber mounting block 5 and the silica gel strip 20. The ends of the plurality of first one-way tubes 30 away from the water tank 29 penetrate through the top walls of the two silica gel strips 20 and are respectively connected with the plurality of square tubes 35. The first one-way tube 30, the second one-way tube 31 and the connecting tube 34 are all flexible tubes.

[0025] Refer to Figures 1 to 4, a friction enhancement mechanism is installed on the second finger joint 2 for enhancing the friction between the prosthetic finger and the object being grasped. The friction enhancement mechanism includes an installation groove 7 and a connecting belt 17. The installation groove 7 is opened at the top end of the second finger joint 2, and a micro air pump 9 is installed in the installation groove 7. A porous plate 8 is detachably installed at the opening of the top end of the installation groove 7. The porous plate 8 is used to protect the micro air pump 9 from external physical damage and also allows external gas to smoothly enter the installation groove 7 and be extracted and utilized by the micro air pump 9. At one end of the second finger joint 2 away from the first finger joint 1, an L-shaped fixing plate 11 is installed. A relief groove is opened on the L-shaped fixing plate 11, and two support plates are symmetrically installed at the bottom end of the L-shaped fixing plate 11. A rotating shaft 13 is rotatably connected between the two support plates. A strip-shaped airbag 12 is fixedly wound around the rotating shaft 13. The output end of the micro air pump 9 is installed with a connecting hose. The end of the connecting hose away from the micro air pump 9 penetrates through the inner wall of the installation groove 7 and passes through the relief groove to be connected to the strip-shaped airbag 12, and the length of the connecting hose corresponds to the length of the strip-shaped airbag 12. One end of the connecting belt 17 is fixedly connected to the top end of the strip-shaped airbag 12 near the edge, and a plurality of fixing strips 18 are fixedly connected to the connecting belt 17. A second magnetic plate 16 is installed on the side of the connecting belt 17 away from the second finger joint 2, and the sides of the connecting belt 17 and the fixing strips 18 facing the second finger joint 2 are both in contact with the strip-shaped airbag 12. A first magnetic plate 15 is installed at the bottom end of the L-shaped fixing plate 11. Two volute springs 14 are installed on the rotating shaft 13, and the rotating shaft 13 is connected to the L-shaped fixing plate 11 through the volute springs 14.

[0026] When the present invention is in use, the first finger joint 1, the second finger joint 2, and the third finger joint 3 can be driven to rotate through the link structure 4, so as to realize the grasping and taking of an object. Since the fingertip part of the prosthetic finger (i.e., the rubber mounting block 5 and various mechanisms thereon) comes into contact with the external object more frequently than other positions, this part is more likely to be damaged. If the entire prosthetic finger is replaced after damage, the cost will be too high. Therefore, when the fingertip position is damaged and needs to be replaced, the two pressing blocks 25 are squeezed into the third finger joint 3. When the pressing blocks 25 are pressed, the pressing plate 26 will squeeze the triangular locking block 24, so that the triangular locking block 24 enters the groove on the embedding block 21. Since the height of the pushing groove is greater than the height of the groove and the height of the pushing groove corresponds to the height of the pressing plate 26, the pressing plate 26 can be prevented from entering the groove. Then, the rubber mounting block 5 is pulled outwards, so that the embedding block 21 is disengaged from the embedding groove in the third finger joint 3. At this time, the pressing blocks 25 and the pressing plate 26 both return to their original positions under the action of the second spring.

[0027] After that, take a new rubber mounting block 5 and insert the embedding block 21 on it into the embedding groove in the third phalanx 3. At this time, the triangular clamping block 24 will be clamped in the propulsion groove in the embedding groove under the action of the first spring, so that the replacement of the fingertip part on the prosthetic finger can be completed quickly and conveniently, reducing the cost of damage replacement. Moreover, this replacement operation can be completed with one hand. The shape of the triangular clamping block 24 is set to ensure that the embedding block 21 can smoothly enter the embedding groove in the third phalanx 3.

[0028] When it is necessary to pick up small pill-shaped objects on a plane (such as pills, capsules, etc.), by controlling the two first electric telescopic rods 27, the two transmission plates 28 and the strip plates on the two transmission plates 28 move away from each other, so that the two silica gel strips 20 are separated from each other, and the two silica gel sheets 6 are respectively extruded (since silica gel is an elastic material, the silica gel sheets 6 being extruded will undergo elastic deformation, so that the two silica gel strips 20 can be smoothly separated from each other). Subsequently, place the pill-shaped object in the gap between the two silica gel strips 20, and then control the first electric telescopic rod 27 to make the two transmission plates 28 and the two strip plates move closer to each other, so that the two silica gel strips 20 start to move towards each other until the pill-shaped object is picked up, thus realizing the stable picking up of small pill-shaped objects. In addition, during the process of the two silica gel strips 20 separating from each other, the first one-way tube 30 has enough extra length to adapt to the movement of the silica gel strips 20 (the first one-way tube 30 is a flexible tube).

[0029] When it is necessary to pick up sheet-shaped objects on a plane or dropped on the ground, by controlling the motor 22, the transmission disk 23 can be rotated, and the rotation of the transmission disk 23 drives the rubber mounting block 5 and the silica gel sheet 6 to rotate until both the rubber mounting block 5 and the silica gel sheet 6 rotate 180 degrees. Since a plurality of micro suction cups 19 are fixedly embedded at the top of the rubber mounting block 5, the rotated rubber mounting block 5 can make the micro suction cups 19 on it face the sheet-shaped object, and the sheet-shaped object can be picked up from the plane or the ground through the adsorption of the plurality of micro suction cups 19, thus realizing the stable picking up of the sheet-shaped object. Moreover, if it is necessary to pick up small sheet-shaped objects, there is no need to control the motor 22. Just make the third phalanx 3 tilt downward under the action of the link structure 4, and use the micro suction cup 19 fixedly embedded at one end of the rubber mounting block 5 away from the third phalanx 3 to adsorb and pick up the small sheet-shaped object.

[0030] When it is necessary to use the prosthetic finger to pick up an object with water marks on the surface (such as a cup with water drops on the surface), the silicone sheet 6 and the silicone strip 20 will contact the surface of the object and apply pressure, and under the squeezing of the silicone sheet 6 and the silicone strip 20, the water marks on the surface of the object will be squeezed out and dispersed, and under the action of capillary phenomenon, they will be guided into the branch groove 33 in the silicone sheet 6 and the branch groove 33 and the main groove 32 in the silicone strip 20, and then the second electric telescopic rod 36 is controlled to make the piston 37 in the water tank 29 move downward (normally, the piston 37 in the water tank 29 is at the top). Since the multiple first one-way tubes 30 are respectively connected to the multiple square tubes 35, and the multiple square tubes 35 are connected through the connecting tube 3 4 is connected to the main groove 32. Therefore, when the piston 37 moves downward, the water in the main groove 32 will be sucked by the connecting pipe 34 and will be sucked into the water tank 29 through the connecting pipe 34, the square pipe 35 and the first one-way pipe 30 in sequence. In this process, since the main groove 32 and the branch grooves 33 are arranged in a cross shape, the water in the branch grooves 33 will be gathered into the main groove 32 under the suction of the connecting pipe 34 and finally be sucked into the water tank 29 together. Then, the piston 37 is moved up a certain distance by controlling the second electric telescopic rod 36, and the air above the piston 37 in the water tank 29 is discharged through the second one-way pipe 31 (the first one-way pipe 30 and the second one-way pipe 31 can only flow in one direction).

[0031] Afterwards, by repeatedly moving the piston 37 up and down, the water in the main groove 32 and the branch groove 33 can be continuously extracted and stored in the water tank 29. This process can significantly reduce the moisture content between the silicone sheet 6 and the silicone strip 20 and the surface of the object, thereby effectively reducing the interference of water stains on the grasping operation of the prosthetic finger, and thus effectively improving the stability of picking up objects with water stains on the surface. The opening of the main groove 32 and the branch groove 33 can also increase the friction between the silicone sheet 6 and the silicone strip 20 and the object, thereby further improving the stability of picking up the object.

[0032] When it is necessary to pick up deformable or fragile objects, pull the strip-shaped airbag 12 in the direction of the third phalanx 3. At this time, the rotating shaft 13 rotates with the pulling of the strip-shaped airbag 12, and the two scroll springs 14 can twist the rotating shaft 13 to make the pulled strip-shaped airbag 12 in a straight state. Under the action of the pulling force, the second magnetic plate 16 on the connecting belt 17 will separate from the first magnetic plate 15 at the bottom of the L-shaped fixing plate 11 (normally, the second magnetic plate 16 and the first magnetic plate 15 are in a state of mutual adsorption). When the strip-shaped airbag 12 is pulled to the silica gel strip 20, turn up the connecting belt 17 and multiple fixing strips 18, and control the first electric telescopic rod 27 to make the two silica gel strips 20 clamp and fix the fixing strips 18. Then turn on the micro air pump 9 and inflate the strip-shaped airbag 12 through the connecting hose, so that the strip-shaped airbag 12 expands (since the length of the connecting hose corresponds to the length of the strip-shaped airbag 12, the pulled strip-shaped airbag 12 will not affect the gas transmission of the connecting hose), thereby filling the gap between the prosthetic finger and the object (that is, increasing the contact area between the prosthetic finger and the object), and then improving the friction between the prosthetic finger and the object.

[0033] When grasping and picking up deformable or fragile objects with the prosthetic finger, since too much force cannot be applied during grasping, it is easy to slip during the grasping process. The inflated strip-shaped airbag 12 can increase the friction between the prosthetic finger and the object, thus significantly reducing the risk of the object slipping. After using the strip-shaped airbag 12, control the micro air pump 9 to pump out the gas in the strip-shaped airbag 12 to make it return to the flat state. Then control the first electric telescopic rod 27 to remove the fixing strip 18 from between the two silica gel strips 20 and reset the connecting belt 17 and the fixing strip 18. Under the action of the scroll spring 14 on the rotating shaft 13, the strip-shaped airbag 12 will be wound up by the rotating shaft 13. As the strip-shaped airbag 12 is gradually wound up, the second magnetic plate 16 on the fixing strip 18 gradually approaches and finally contacts and adsorbs the first magnetic plate 15, thus completing the fixing after the strip-shaped airbag 12 is wound up and reset.

[0034] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An underactuated prosthetic finger device with multiple grasping modes, comprising a first finger joint (1), a second finger joint (2), a third finger joint (3) and a connecting rod structure (4), wherein the first finger joint (1), the second finger joint (2) and the third finger joint (3) are interconnected via the connecting rod structure (4), and a silicone block (10) is installed at the bottom end of the second finger joint (2), characterized in that: Also includes: A clamping mechanism and a water-taking and absorbing mechanism, the clamping mechanism being arranged on a first finger joint (1), the first finger joint (1) being detachably mounted with a rubber mounting block (5) via the clamping mechanism, the clamping mechanism being used to realize convenient replacement of the rubber mounting block (5), the water-taking and absorbing mechanism being arranged on the rubber mounting block (5) and being used to enable the prosthetic finger to realize stable picking up of sheet-like objects and small pill-like objects and to extract water marks on the surface of the picked up object; A friction enhancing mechanism is provided on the second finger joint (2) and is used to enhance the friction between the prosthetic finger and the object being picked up.

2. The underactuated prosthetic finger device with multiple grasping modes according to claim 1, characterized in that: The clamping mechanism comprises an embedding groove and an embedding block (21), wherein the embedding groove is formed at an end of the third finger joint (3) away from the second finger joint (2), a rotating assembly is mounted on the embedding block (21), and the embedding block (21) is connected to the rubber mounting block (5) via the rotating assembly, the embedding block (21) is inserted into the embedding groove, and grooves are formed on both sides of the embedding block (21), a first spring is mounted in the groove, and the groove is connected to a triangular clamping block (24) via the first spring, and sliding grooves are formed on both sides of the groove, two sliding blocks are symmetrically mounted on one side of the triangular clamping block (24) facing the first spring, and the triangular clamping block (24) is slidably connected in the sliding groove via the sliding blocks, two thrust grooves are formed on the inner wall of the embedding groove, and the positions of the two thrust grooves correspond to the positions of the two grooves, the triangular clamping block (24) is located in the thrust groove, and a thrust assembly is provided in the third finger joint (3) and the two thrust grooves for applying thrust to the triangular clamping block (24).

3. The underactuated prosthetic finger device with multiple grasping modes according to claim 2, characterized in that: The rotating assembly comprises a mounting cavity, the mounting cavity being opened at one end of the embedding block (21) facing the rubber mounting block (5), and a motor (22) being mounted in the mounting cavity, a transmission disc (23) being mounted at the output end of the motor (22), and the motor (22) being connected to the rubber mounting block (5) via the transmission disc (23), and an outer wall of the transmission disc (23) being arranged in contact with an inner wall of the mounting cavity.

4. The underactuated prosthetic finger device with multiple grasping modes according to claim 2, characterized in that: The pushing assembly comprises two extrusion plates (26) and two force-applying grooves, the two force-applying grooves being arranged inside the third finger joint (3), and the two force-applying grooves are both provided with through openings on the outward side, the through opening radius being smaller than the radius of the force-applying groove, and a pressing block (25) being arranged in the through opening, a limit block being installed on the outer wall of the pressing block (25), and the pressing block (25) being slidably connected in the force-applying groove through the limit block, a connecting rod and a second spring being installed at the inward end of the pressing block (25), and the pressing block (25) being connected to the inner wall of the force-applying groove through the second spring, the inward end of the connecting rod passing through the inner wall of the force-applying groove and being fixedly connected with an extrusion plate (26), the extrusion plate (26) being slidably connected in the pushing groove, the height of the pushing groove being larger than the height of the groove, and the height of the pushing groove corresponding to the height of the extrusion plate (26).

5. The underactuated prosthetic finger device with multiple grasping modes according to claim 1, characterized in that: The water-taking and absorbing mechanism comprises two silicone sheets (6) and a plurality of micro suction cups (19), wherein the plurality of micro suction cups (19) are respectively fixedly embedded in the top of the rubber mounting block (5) and an end away from the third finger joint (3), the tops of the two silicone sheets (6) are both provided with connecting plates, and the two silicone sheets (6) are symmetrically installed on the rubber mounting block (5) via the connecting plates, the rubber mounting block (5) is provided with a separation component, and the rubber mounting block (5) is connected to two silicone strips (20) via the separation component, the two silicone strips (20) are in contact with each other, and the two silicone strips (20) face outwards. One side is in contact with two silicone sheets (6), respectively. The silicone sheet (6) and the silicone strip (20) are both located below the rubber mounting block (5), and a plurality of branch grooves (33) are provided at the bottom ends of the silicone sheet (6) and the silicone strip (20). The positions of the plurality of branch grooves (33) on the silicone sheet (6) and the silicone strip (20) correspond to each other. A plurality of main grooves (32) are provided at the bottom end of the silicone strip (20), and a water absorbing component is provided on the rubber mounting block (5), the silicone strip (20) and the main groove (32) for absorbing water in the main groove (32) and the branch groove (33).

6. The underactuated prosthetic finger device with multiple grasping modes according to claim 5, characterized in that: The main groove (32) and the branch groove (33) are arranged in a cross shape, and the width of the main groove (32) is greater than the width of the branch groove (33).

7. The underactuated prosthetic finger device with multiple grasping modes according to claim 5, characterized in that: The separation component comprises two strip grooves, the two strip grooves are both opened at the bottom end of the rubber mounting block (5), and a first electric telescopic rod (27) is installed inside the two strip grooves, the output ends of the two first electric telescopic rods (27) face oppositely, and a transmission plate (28) is installed on both sides, the bottom ends of the two transmission plates (28) are respectively fixedly connected to the top ends of the two silicone strips (20), and the two transmission plates (28) are located close to the side where the two silicone strips (20) are in contact, and the opposite ends of the two transmission plates (28) are both installed with a strip plate, and the two strip plates are respectively installed on the top ends of the two silicone strips (20).

8. The underactuated prosthetic finger device with multiple grasping modes according to claim 5, characterized in that: The water absorption assembly comprises a square groove, an L-shaped connecting block and two through grooves, the square groove is opened at the bottom end of the rubber mounting block (5), and a water tank (29) is installed on the inner side wall of the square groove, the L-shaped connecting block is installed at the bottom end of the rubber mounting block (5), and a second electric telescopic rod (36) is installed on the L-shaped connecting block, the output end of the second electric telescopic rod (36) passes through the bottom end of the water tank (29) and is fixedly connected to a piston (37), and the piston (37) is sealingly slidably connected in the water tank (29); The two through grooves are respectively penetrated and opened at one end of the two silicone strips (20); a plurality of square tubes (35) are installed on the inner bottom wall of the through groove; a plurality of connecting tubes (34) are installed at the bottom end of the square tubes (35); the bottom ends of the plurality of connecting tubes (34) all penetrate the inner bottom wall of the through groove and are located in the main groove (32); a second one-way tube (31) and a plurality of first one-way tubes (30) are installed at the top end of the water tank (29); an end of the second one-way tube (31) away from the water tank (29) is located in the gap between the rubber mounting block (5) and the silicone strip (20); an end of the plurality of first one-way tubes (30) away from the water tank (29) penetrates the top walls of the two silicone strips (20) and is respectively connected to the plurality of square tubes (35); the first one-way tube (30), the second one-way tube (31) and the connecting tube (34) are all hoses.

9. The underactuated prosthetic finger device with multiple grasping modes according to claim 1, characterized in that: The friction enhancing mechanism comprises a mounting groove (7) and a connecting belt (17); the mounting groove (7) is provided at the top of the second finger joint (2), and a micro air pump (9) is installed in the mounting groove (7); an L-shaped fixing plate (11) is installed at the end of the second finger joint (2) away from the first finger joint (1); a clearance groove is provided on the L-shaped fixing plate (11), and two support plates are symmetrically installed at the bottom end of the L-shaped fixing plate (11); the two support plates are rotatably connected to a rotating shaft (13), and a strip air bag (12) is fixedly wound around the rotating shaft (13); The output end of the micro air pump (9) is provided with a connecting hose, the end of the connecting hose away from the micro air pump (9) passes through the inner wall of the installation groove (7), and passes through the clearance groove to be connected to the strip air bag (12), one end of the connecting belt (17) is fixedly connected to the top of the strip air bag (12) near the edge, and a plurality of fixing strips (18) are fixedly connected to the connecting belt (17), a second magnetic plate (16) is installed on the side of the connecting belt (17) away from the second finger joint (2), and the sides of the connecting belt (17) and the fixing strips (18) facing the second finger joint (2) are in contact with the strip air bag (12), a first magnetic plate (15) is installed on the bottom end of the L-shaped fixing plate (11), two volute springs (14) are installed on the rotating shaft (13), and the rotating shaft (13) is connected to the L-shaped fixing plate (11) via the volute springs (14).

10. The underactuated prosthetic finger device with multiple grasping modes according to claim 9, characterized in that: A porous plate (8) is detachably mounted at the top opening of the mounting groove (7), and the length of the connecting hose corresponds to the length of the strip-shaped airbag (12).

Images