Biopsy forceps for endoscope

Abstract

The invention discloses biopsy forceps for an endoscope, and belongs to the technical field of medical instruments, the biopsy forceps comprise a handle, a forceps seat, an outer sheath tube, a driving wire, two forceps heads and two flexible driving parts, one end of the forceps seat is provided with a mounting groove, and the other end of the forceps seat forms a connecting end; each plier head comprises a plier opening body, a rotating arm and a guide surface are formed at the lower end of each plier opening body, the periphery of each rotating arm is a circular cylindrical surface, a fixing hole is formed in each plier head, and the rotating arms of the two plier heads are hinged in the mounting groove of the plier seat through a hinge pivot after being mutually folded; the flexible driving piece comprises a straight part and a bent part, and the bent part is wound on the circular cylindrical surface of the inner side of the corresponding rotating arm and is connected with the fixing hole of the jaw body; when the driving wire moves forwards or backwards to drive the flexible driving piece to be driven, the flexible driving piece is restrained to transmit power in the axial direction to drive the two forceps heads to be opened or closed. The biopsy forceps have the advantages of being large in jaw opening degree, large in meshing force, convenient and fast to operate and small in structural size.

Description

Technical Field

[0001] The invention belongs to the technical field of medical instruments, and in particular relates to a biopsy forceps used for an endoscope. Background Art

[0002] In early medical practice, doctors tried to use some simple tools to obtain diseased tissue in the body for pathological analysis, but these tools were not specially designed for living sampling. For example, they might try to use simple instruments such as ordinary tweezers or pliers, but they had great deficiencies in accuracy, safety and applicability. The tools of this period could hardly reach the lesion site accurately and obtain sufficient and high-quality tissue samples, and they were prone to damage the surrounding normal tissues.

[0003] With the birth and continuous development of endoscopic technology, biopsy forceps that match it began to appear. The currently commonly used endoscopic biopsy forceps are mainly rigid connecting rod structures. Although the connecting rod structure itself has the advantage of good reliability, the connecting rod structure of the complete clamp head is relatively complex and contains multiple connecting rod parts, which to a certain extent limits the miniaturization design of the biopsy forceps; for some particularly narrow cavities or small lesions, there may be problems such as being too large or too long to reach or inconvenient to operate; at the same time, during the bite process of the biopsy forceps with a rigid connecting rod structure, the angle of the clamp head continues to decrease, and its transmission connecting rod and the clamp head tend to be collinear, and the transmission angle of the connecting rod approaches the "dead point". Most of the force transmitted by the connecting rod passes through the rotation center of the clamp head, making it impossible for the clamp head to obtain a greater bite force. This defect will affect the grasping effect of tissue samples during clinical use, and may cause tissue tearing and bleeding, incomplete sampling, or inability to obtain enough tissue for pathological examination, resulting in patient pain and increased surgical costs. Summary of the invention

[0004] Technical problem to be solved: In view of the shortcomings of biopsy forceps in the prior art, the present invention provides a biopsy forceps for endoscopes, which has a large jaw opening, a strong bite force and a small structural size under the same specifications, has few components, a small turning radius of the forceps head, and is easy to operate.

[0005] Technical solution: The biopsy forceps for endoscope described in the present invention include: handle; A clamp seat, wherein two connecting plates are disposed opposite to each other at one end of the clamp seat, a mounting groove is formed between the two connecting plates, and connecting pin holes communicating with the mounting groove are disposed opposite to each other on the two connecting plates; a connecting end is formed at the other end of the clamp seat, and a guide channel communicating with the mounting groove is provided at the connecting end; An outer sheath tube, wherein a driving wire is arranged inside the outer sheath tube, and both ends of the outer sheath tube are respectively fixedly connected to the connecting ends of the handle and the clamp seat; one end of the driving wire is connected to the handle, and the other end of the driving wire extends into the guide channel; Two pliers heads are arranged to cooperate with each other, the pliers heads include a jaw body, a rotating arm and a guide surface are formed at the lower end of the jaw body, the outer periphery of the rotating arm is a circular cylinder, and the axis of the rotating arm is provided with a hinge hole; the pliers heads are provided with a fixing hole at the connection between the jaw body and the root of the rotating arm, and the fixing hole extends from the inner side of the jaw body to the outer side of the jaw; the rotating arms of the two pliers heads are overlapped with each other and hinged in the mounting groove of the pliers seat through a hinge pivot, the circular cylinders of the rotating arms of the two pliers heads are arranged correspondingly to the guide surfaces of the pliers heads, and a channel for the flexible driving member to pass through is formed between the circular cylinder and the corresponding guide surface; Two flexible driving members are respectively arranged corresponding to the corresponding pliers heads, the flexible driving members are tough, can be bent but cannot be compressed axially, and after installation, they include a straight part and a curved part, one end of the two straight parts is fixedly connected to the free end of the driving wire through a connecting part, and the curved part is wound around the inner circular cylindrical surface of the corresponding rotating arm and connected to the fixing hole of the jaw body; When the driving wire moves forward or backward to drive the flexible driving member to move, the flexible driving member is constrained to transmit power along the axial direction to drive the two clamp heads to open or close.

[0006] Preferably, the center distance between the fixing hole provided on the jaw body and the hinge hole of the rotating arm is 0.5~5mm.

[0007] Preferably, the jaw body is provided with a slot outside the fixing hole, and the distal end of the bent portion is provided with a limiting end mounted in the slot.

[0008] Preferably, a pressure relief hole communicating with the inside and outside of the jaws is provided in the center of the jaw body.

[0009] Preferably, the connecting end is provided with a connecting counterbore at the outer end of the guide channel, the inner diameter of the connecting counterbore is larger than the diameter of the guide channel, and one end of the outer sheath tube is fixedly connected in the connecting counterbore.

[0010] Preferably, the diameters of the straight portion and the curved portion of the flexible driving member are 0.1-0.5 mm, and the diameter of the limiting end is larger than the diameter of the curved portion.

[0011] Compared with the prior art, the present invention has the following beneficial effects: 1. In terms of power transmission, the biopsy forceps of the present invention drive the clamp head body to open and close through its rotating arm through a flexible driving member. The flexible driving member and the corresponding rotating arm cooperate with each other in the same way as the principle of pulley transmission, so that the driving pulling force can be directly transmitted to the clamp head body through the flexible driving rod. The angle between the direction of the force and the force arm can be almost vertical, and the angle will not decrease during the opening and closing process, so that the clamp head body maintains the maximum force component during the biting process, and there is no "dead point" of the rigid connecting rod mechanism, which improves the pulling force transmission efficiency of the biopsy forceps, enhances the biting force of the jaw body, and makes the living tissue sampling process smooth and accurate; 2. The flexible driving member only needs to occupy a very small movement space of the clamp seat. The power is transmitted to the flexible driving rod through the driving wire to act on the central fixing hole of the jaw body, with the hinged pivot as the fulcrum. The power arm of the clamp head bites and the resistance arm formed by the bite point are on the same side of the fulcrum, making the length of the clamp head shorter than that of the rigid connecting rod clamp head, which can greatly shorten the length of the clamp head and better adapt to the sampling of various narrow cavities; 3. The jaws of the biopsy forceps have a large opening, strong bite force and small structural size under the same specifications. It has few components, a small turning radius of the forceps head, and is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the three-dimensional structure of the biopsy forceps of the present invention in an open state; Figure 2 for Figure 1 The front view of the structure of the middle biopsy forceps in the closed state; Figure 3 for Figure 1 Schematic diagram of the three-dimensional structure of the middle clamp seat; Figure 4 for Figure 1 A schematic diagram of the three-dimensional structure of the middle clamp head; Figure 5 for Figure 1 Schematic diagram of the structure of the flexible driving part; Figure 6 for Figure 2 The middle section view shows the biopsy forceps in the closed position; Figure 7 for Figure 1 Cross-sectional view of the biopsy forceps in the open position.

[0013] Figure numerals: 100, biopsy forceps; 1, forceps seat; 11, connecting end; 12, connecting plate; 13, mounting slot; 14, connecting pin hole; 15, connecting countersunk hole; 2, forceps head; 21, shear jaws; 22, fixing hole; 23, slot; 24, rotating arm; 25, overflow hole; 26, hinge hole; 27, guide surface; 3, flexible driving member; 31, straight portion; 32, bent portion; 33, limit end; 4, hinge pivot; 5, outer sheath; 6, driving wire; 7, connecting portion. DETAILED DESCRIPTION

[0014] To make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the following will be combined with the attached Figures 1 to 7 The technical solutions of the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0015] like Figure 1~2 As shown, the present invention discloses a biopsy forceps for endoscope, wherein the biopsy forceps 100 comprises a handle (not shown in the figure), a forceps seat 1, an outer sheath 5, two forceps heads 2 arranged in opposite cooperation with each other, and two flexible driving members 3 respectively arranged corresponding to the corresponding forceps heads 2.

[0016] like Figure 3 As shown, two connecting plates 12 are arranged opposite to each other at one end of the clamp seat 1, a mounting groove 13 is formed between the two connecting plates 12, and connecting pin holes 14 communicating with the mounting groove 13 are arranged opposite to each other on the two connecting plates 12. A connecting end 11 is formed at the other end of the clamp seat 1, and a guide channel 16 communicating with the mounting groove 13 is provided at the connecting end 11, and the driving wire 6 can pass through the guide channel 16 to connect with the flexible driving member 3. A connecting countersunk hole 15 is arranged at the outer end of the guide channel 16 at the connecting end 11, and the inner diameter of the connecting countersunk hole 15 is larger than the diameter of the guide channel 16, and one end of the outer sheath 5 is fixedly connected in the connecting countersunk hole 15.

[0017] A driving wire 6 is arranged in the outer sheath tube 5. The outer sheath tube 5 can adopt a spring tube, a polymer outer tube or a composite braided sheath tube and other structures. Any outer sheath tube that can meet the pushing performance, bending performance and inner cavity retention requirements can be used. It has excellent expansion and deformation performance and can protect the driving wire 6. The two ends of the outer sheath tube 5 are respectively fixedly connected to the connecting end 11 of the handle and the clamp seat 1. One end of the driving wire 6 is connected to the handle, and the other end of the driving wire 6 extends into the guide channel 16. The driving wire 6 can be tensioned or relaxed by the handle, and the handle adopts the existing technology to realize the driving function.

[0018] like Figure 4As shown, the pliers head 2 includes a jaw body 21, a rotating arm 24 and a guide surface 27 are formed at the lower end of the jaw body 21, the rotating arm 24 and the guide surface 27 each occupy approximately 1 / 2 of the width of the jaw body 21, the outer periphery of the rotating arm 24 is a circular cylindrical surface 28, and the axis of the rotating arm 24 is provided with a hinge hole 26 for the installation of the hinge pivot 4. The pliers head 2 is provided with a fixing hole 22 at the connection between the jaw body 21 and the root of the rotating arm 24, the fixing hole 22 extends from the inner side of the jaw body 21 to the outer side of the jaw, the center distance between the fixing hole 22 provided in the jaw body 21 and the hinge hole 26 of the rotating arm 24 is 0.5~5mm, and the jaw body 21 is provided with a card slot 23 at the outer side of the fixing hole 22. The rotating arms 24 of the two clamp heads 2 are overlapped with each other and hinged in the mounting groove 13 of the clamp seat 1 through the hinge pivot 4. The circular cylindrical surfaces 28 of the rotating arms 24 of the two clamp heads 2 are arranged correspondingly to the guide surfaces 27 of the clamp heads 2, and a channel for the flexible driving member to pass through is formed between the circular cylindrical surfaces 28 and the corresponding guide surfaces 27, so that the two jaw bodies 21 can be opened or closed along the hinge pivot 4. A pressure relief hole 25 connecting the inside and outside of the jaws is arranged in the center of the jaw body 21 to meet the discharge of body fluids that may be generated when sampling living tissue and avoid shearing difficulties caused by liquid pressure.

[0019] like Figure 5 As shown, the flexible driving member 3 has toughness, it can be bent but cannot be compressed axially, and after installation, it includes a straight portion 31 and a curved portion 32, one end of the two straight portions 31 is fixedly connected to the free end of the driving wire 6 through the connecting portion 7, the curved portion 32 is wound around the inner circular cylindrical surface 28 of the corresponding rotating arm 24 and connected to the fixing hole 22 of the jaw body 21, and the distal end of the curved portion 32 is provided with a limit end 33 clamped in the card slot 23; it should be noted that the flexible driving member 3 and the jaw body 21 can also be fixed by welding, which can realize the driving of the flexible driving member 3 and the jaw body 21. Among them, the diameters of the straight portion 31 and the curved portion 32 of the flexible driving member 3 are 0.1~0.5mm, and the diameter of the limit end 33 is larger than the diameter of the curved portion 32. In the normal state, the curved parts 32 of the two flexible driving members 3 are correspondingly supported on the circular cylindrical surface 28 of the rotating arm 24 of the pliers head 2, so that the two pliers heads 2 are in an open state; when sampling is required, the flexible driving member 3 is deformed by pulling the driving wire 6 by the handle, and the two jaw bodies 21 are driven to rotate and close along the hinge pivot 4 to achieve the sampling operation, that is, the driving wire 6 drives the flexible driving member 3 forward or backward to drive the flexible driving member 3 to transmit power axially to drive the two pliers heads 2 to open or close. It should be noted that the flexible driving member 3 can be made of metal ropes, steel wires, nickel-titanium wires, etc., or can be made of polymer wires with a certain strength such as PET wires, nylon wires, aramid braided wires, etc., or made of braided wires of composite materials. The flexible driving member 3 and the fixing hole 22 of the pliers head 2 can be fixedly connected by welding, bonding, riveting, etc.

[0020] Working principle or working method of the present invention: like Figure 6-7 As shown, in terms of power transmission, the biopsy forceps of the present invention drive the clamp head 2 body to open and close through its rotating arm 24 through the flexible driving member 3. The flexible driving member 3 and the corresponding rotating arm 24 cooperate with each other on the principle of pulley transmission, so that the driving tension can be directly transmitted to the clamp head 2 body through the flexible driving rod. The angle between the direction of the force and the force arm can be almost vertical, and the angle will not decrease during the opening and closing process, so that the clamp head 2 body maintains the maximum force component during the biting process, and there is no "dead point" of the rigid connecting rod mechanism, which improves the tension transmission efficiency of the biopsy forceps, enhances the biting force of the jaw body 21, and makes the living tissue sampling process smooth and accurate. The flexible driving member 3 only occupies a very small movement space of the clamp seat 1. The power is transmitted to the flexible driving rod through the driving wire 6 to act on the central fixing hole 22 of the jaw body 21, with the hinge pivot 4 as the fulcrum. The power arm that is equivalent to the bite of the clamp head 2 and the resistance arm formed by the bite point are on the same side of the fulcrum, so that the length of the clamp head 2 is shorter than that of the rigid connecting rod clamp head 2, which can greatly shorten the length of the clamp head 2 and better adapt to sampling of various narrow cavities.

[0021] The above are preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A biopsy forceps for an endoscope, characterized in that: Biopsy forceps (100) includes: handle; A clamp seat (1), wherein two connecting plates (12) are disposed opposite to each other at one end of the clamp seat (1), a mounting groove (13) is formed between the two connecting plates (12), and connecting pin holes (14) communicating with the mounting groove (13) are disposed opposite to each other on the two connecting plates (12); a connecting end (11) is formed at the other end of the clamp seat (1), and a guide channel (16) communicating with the mounting groove (13) is provided at the connecting end (11); An outer sheath tube (5), wherein a driving wire (6) is arranged inside the outer sheath tube (5), and both ends of the outer sheath tube (5) are respectively fixedly connected to the connecting ends (11) of the handle and the clamp seat (1); one end of the driving wire (6) is connected to the handle, and the other end of the driving wire (6) extends into the guide channel (16); Two pliers (2) are arranged to cooperate with each other, the pliers (2) comprising a jaw body (21), a rotating arm (24) and a guide surface (27) formed at the lower end of the jaw body (21), the outer periphery of the rotating arm (24) being a circular cylindrical surface (28), and the axis of the rotating arm (24) being provided with a hinge hole (26); the pliers (2) being provided with a fixing hole (22) at the connection between the jaw body (21) and the root of the rotating arm (24), the fixing hole (22) extending from the inner side of the jaw body (21) to the outer side of the jaw; the rotating arms (24) of the two pliers (2) are overlapped with each other and are hingedly connected in the mounting groove (13) of the pliers seat (1) through a hinge pivot (4), the circular cylindrical surfaces (28) of the rotating arms (24) of the two pliers (2) being arranged correspondingly to the guide surface (27) of the pliers (2), and a channel for a flexible driving member to pass through is formed between the circular cylindrical surface (28) and the corresponding guide surface (27); Two flexible driving members (3) are respectively arranged corresponding to the corresponding pliers heads (2), the flexible driving members (3) are tough and can be bent but cannot be axially compressed, and after installation, they include a straight portion (31) and a curved portion (32), one end of the two straight portions (31) is fixedly connected to the free end of the driving wire (6) through a connecting portion (7), and the curved portion (32) is wound around the inner circular cylindrical surface (28) of the corresponding rotating arm (24) and connected to the fixing hole (22) of the jaw body (21); When the driving wire (6) moves forward or backward to drive the flexible driving member (3) to move, it constrains the flexible driving member (3) to transmit power in the axial direction to drive the two clamp heads (2) to open or close.

2. The biopsy forceps for endoscope according to claim 1, characterized in that: The center distance between the fixing hole (22) provided in the jaw body (21) and the hinge hole (26) of the rotating arm (24) is 0.5-5 mm.

3. The biopsy forceps for endoscope according to claim 2, characterized in that: The jaw body (21) is provided with a slot (23) outside the fixing hole (22), and the distal end of the bent portion (32) is provided with a limiting end (33) which is mounted in the slot (23).

4. The biopsy forceps for endoscope according to claim 1, characterized in that: A pressure relief hole (25) communicating with the inside and outside of the jaws is provided in the center of the jaw body (21).

5. The biopsy forceps for endoscope according to claim 1, characterized in that: The connecting end (11) is located at the outer end of the guide channel (16) and is provided with a connecting countersunk hole (15). The inner diameter of the connecting countersunk hole (15) is larger than the diameter of the guide channel (16), and one end of the outer sheath tube (5) is fixedly connected in the connecting countersunk hole (15).

6. The biopsy forceps for endoscope according to claim 3, characterized in that: The diameters of the straight portion (31) and the curved portion (32) of the flexible driving member (3) are 0.1-0.5 mm, and the diameter of the limiting end (33) is greater than the diameter of the curved portion (32).

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