CN112590160B

CN112590160B - Extrusion device for processing outer skin layer of insertion tube of endoscope

Info

Publication number: CN112590160B
Application number: CN202110227809.8A
Authority: CN
Inventors: 李奕; 孙平; 杨俊风
Original assignee: Daichuan Medical Shenzhen Co ltd
Current assignee: Daichuan Medical Shenzhen Co ltd
Priority date: 2021-03-02
Filing date: 2021-03-02
Publication date: 2021-06-04
Anticipated expiration: 2041-03-02
Also published as: CN112590160A

Abstract

The application provides an extrusion device for processing an outer skin layer of an endoscope insertion tube, wherein the endoscope insertion tube comprises an outer skin layer and a flexible tube body, the flexible tube body comprises a spiral tube and a woven layer sleeved on the outer side of the spiral tube, and the outer skin layer is coated outside the woven layer; the extrusion device comprises a molding unit, an extrusion unit and a surface treatment unit. The forming unit comprises a forming channel for the flexible pipe body to advance; the extrusion unit is communicated with the forming channel and is used for extruding the resin material into the forming channel so as to ensure that part of the resin material is coated on the surface of the flexible pipe body to form the outer skin layer and part of the resin material penetrates through the woven layer to be filled into the bending gap of the spiral pipe; the surface treatment unit is communicated with the forming channel and used for smoothing the surface of the outer skin layer coated on the flexible pipe body. The extrusion device of the application can produce the insertion tube with better smoothness on the surface.

Description

Extrusion device for processing outer skin layer of insertion tube of endoscope

Technical Field

The application relates to the field of manufacturing of endoscope insertion tubes, in particular to an extrusion device for processing an outer skin layer of an endoscope insertion tube.

Background

In the existing extrusion process for processing the outer skin layer of the insertion tube of the endoscope, water ripples are often formed on the surface of the outer skin layer of the insertion tube due to the extrusion process, so that the insertion tube is highly uncomfortable when being inserted into a subject.

The above information disclosed in this background section is only for enhancement of understanding of the background of the application and therefore it may contain information that does not constitute prior art that is already known to a person of ordinary skill in the art.

Disclosure of Invention

An object of the present application is to provide an extrusion apparatus for processing an outer skin layer of an endoscope insertion tube to improve smoothness of the surface of the insertion tube produced.

In order to solve the technical problem, the following technical scheme is adopted in the application:

according to an aspect of the present application, an extrusion apparatus for processing an endoscope insertion tube outer skin layer, an endoscope insertion tube includes an outer skin layer and a flexible tube body, the flexible tube body includes a spiral tube and a sheath, and is established a braid outside the spiral tube, the outer skin layer cladding is in an outside of the braid, the extrusion apparatus includes:

a forming unit comprising a forming channel for the flexible pipe body to travel;

an extrusion unit, communicating with the molding passage, for extruding a resin material into the molding passage, so that a part of the resin material is coated on the surface of the flexible pipe body to form the outer skin layer, and a part of the resin material penetrates through the woven layer and is filled into a bending gap of the spiral pipe;

and the surface treatment unit is communicated with the forming channel and is used for smoothing the surface of the outer skin layer coated on the flexible pipe body.

According to an embodiment of the application, the surface treatment unit comprises a scraping mould, the scraping mould comprises a base and an annular scraper arranged on the base, and the annular scraper is used for smoothing the uneven part of the surface of the outer skin layer.

According to an embodiment of the application, an included angle between the knife wall of the annular scraper and the extending direction of the forming channel is 30-60 degrees.

According to an embodiment of the present application, the extrusion unit includes a pressure extrusion unit, the pressure extrusion unit is configured to extrude a resin material in a molten state to the molding passage at an extrusion pressure greater than a preset pressure, and the resin material is coated on the surface of the flexible pipe body to form the outer skin layer;

the preset pressure is greater than or equal to a pressure required for the resin material to penetrate the woven layer to fill the bending gap of the spiral pipe.

According to an embodiment of the present application, the surface treatment unit comprises an atmospheric extrusion unit;

the normal pressure extrusion unit is used for extruding the resin material to the molding channel under normal pressure so as to smooth the pits formed on the surface of the outer skin layer.

According to an embodiment of the application, extrusion device still includes drying unit, drying unit set up in pressure extrude the unit with between the unit is extruded to the ordinary pressure to be used for the drying by pressure extrudes unit extrusion moulding's skin layer.

According to an embodiment of the application, the distance between the pressure extrusion unit and the normal pressure extrusion unit is 20cm-50 cm.

According to an embodiment of the application, the forming unit has a plurality of feed channels communicating with the forming channel; the feeding channels are divided into pressure feeding channels and normal-pressure feeding channels, wherein the pressure feeding channels are connected with extrusion ports of the pressure extrusion units; the pressure feeding channel and the normal-pressure feeding channel are sequentially arranged along the advancing direction of the flexible pipe body;

the outlet of the normal-pressure feeding channel is annular, the flexible pipe body covers the resin material and then penetrates through the outlet of the normal-pressure feeding channel, and the end edge of the side wall of the outlet of the normal-pressure feeding channel is used for smoothing uneven parts of the surface of the resin material covered on the flexible pipe body.

According to an embodiment of the application, the taper angle of the side wall forming the outlet of the normal-pressure feeding channel is 30-49 degrees;

the angle of taper of the side wall forming the outlet of the pressure feed channel is 50 DEG to 80 deg.

According to an embodiment of the application, the extrusion units are multiple, and the extrusion units correspondingly extrude resin materials with multiple hardnesses to the forming channel;

when the flexible pipe body moves in the formed channel, the front end pipe section and the rear end pipe section of the outer skin layer formed by extrusion are softer and harder by adjusting the discharging sequence of the extrusion units.

According to an embodiment of the present application, the extrusion apparatus further comprises a compounding zone;

the mixing area is communicated with the extrusion ports of the extrusion units and the molding channel, and a plurality of resin materials are mixed in the mixing area and then enter the molding channel;

and a mixing part is arranged in the mixing area to promote the mixing of the multiple resin materials.

According to an embodiment of the present application, the extrusion apparatus further comprises a retractor disposed at one side of the molding channel;

in the process of extruding the resin material by the extruding unit, the tractor is used for regulating and controlling the advancing speed of the flexible pipe body to be gradually reduced so that the thickness of the outer skin layer formed by extrusion is gradually increased.

According to an embodiment of the application, extrusion device still includes centering mould, centering mould follows flexible pipe body's axial is worn to establish in the flexible pipe body, and with tight fit between the flexible pipe body.

Through setting up the surface treatment unit in this application, carry out smooth processing to extrusion unit extrusion moulding's skin layer to the surface smoothness of the skin layer of producing has been improved. And because the surface smoothness of the outer skin layer is improved, the friction between the outer skin layer and the resin protective sleeve of the outer layer of the insertion tube is reduced, and the use frequency of the resin protective sleeve is improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The above and other objects, features and advantages of the present application will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.

FIG. 1 is a schematic diagram of an endoscope according to an exemplary embodiment of the present application.

FIG. 2 is a schematic structural view of an endoscope insertion sheath layer according to an exemplary embodiment of the present application.

Fig. 3 is a structural sectional view of a molding unit according to an exemplary embodiment of the present application.

Fig. 4 is a schematic diagram illustrating the structure of an extrusion apparatus according to an exemplary embodiment of the present application.

Fig. 5 is a block diagram illustrating the structure of an extrusion apparatus according to an exemplary embodiment of the present application.

Figure 6 is a schematic diagram of a flexible pipe body within a forming channel according to an example embodiment of the present application.

Fig. 7 is a structural cross-sectional view of a forming unit having a compounding area, according to an example embodiment of the present application.

FIG. 8 is a schematic view of a flow mixing cartridge, flow mixing channel, etc., shown in accordance with an example embodiment of the present application.

FIG. 9 is a schematic structural diagram illustrating a coil assembly according to one embodiment.

FIG. 10 is a schematic diagram illustrating another coil assembly according to one embodiment.

FIG. 11 is a schematic structural diagram illustrating another coil assembly in accordance with one embodiment.

1. An insertion portion; 2. an operation section; 11. an insertion tube; 12. a bending section; 21. a control knob; 22. a control button; 111. a flexible pipe body; 1111. a first spiral pipe; 1112. a second spiral pipe; 112. an outer skin layer; 31. a front end pipe section; 32. a rear end pipe section; 40. a molding unit; 41. an inner mold; 42. an outer mold; 43. an intermediate die; 432. inserting the cover; 441. a first feed channel; 442. a second feed channel; 452. a second feed cylinder; 451. a first feed cylinder; 46. forming a channel; 47. a mixing area; 481. a turbulent flow structure; 471. a mixing bin; 472. a mixed flow channel; 482. a stirring structure; 4771. a feed guide structure; 50. a pressure extrusion unit; 60. a surface treatment unit; 61. scraping the mold; 70. and (4) centering the die.

Detailed Description

While this application is susceptible of embodiment in different forms, there is shown in the drawings and will herein be described in detail only some specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the application and is not intended to limit the application to that as illustrated herein.

Thus, a feature indicated in this specification is intended to describe one of the features of an embodiment of the application and does not imply that every embodiment of the application must have the described feature. Further, it should be noted that this specification describes many features. Although some features may be combined to show a possible system design, these features may also be used in other combinations not explicitly described. Thus, the combinations illustrated are not intended to be limiting unless otherwise specified.

In the embodiments shown in the drawings, directional references (such as up, down, left, right, front, and rear) are used to explain the structure and movement of the various elements of the present application not absolutely, but relatively. These descriptions are appropriate when the elements are in the positions shown in the drawings. If the description of the positions of these elements changes, the indication of these directions changes accordingly.

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the examples set forth herein; rather, these example embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The drawings are merely schematic illustrations of the present application and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and thus their repetitive description will be omitted.

The preferred embodiments of the present application will be further described in detail below with reference to the accompanying drawings of the present specification.

The present embodiment first provides an insertion tube of an endoscope.

Referring to fig. 1, fig. 1 is a schematic diagram of an endoscope according to an exemplary embodiment.

The endoscope of the present embodiment includes an elongated insertion portion 1 inserted into a subject lumen and an operation portion 2 located at a rear end of the insertion portion 1. The operation unit 2 is connected to the insertion unit 1. Wherein, the front and back directions of the endoscope can be as follows: the end of the endoscope close to the subject is in the front direction, and the end of the endoscope close to the operator is in the rear direction. Here, the subject may be a human, an animal, or other inanimate structure.

The endoscope of the present embodiment may be a disposable endoscope. The disposable endoscope discards the polluted part after use, so that the sanitation degree of the endoscope can be improved, and the safe use of the examinee can be ensured. Since the operation part 2 and the insertion part 1 are contaminated during use, the operation part 2 and the insertion part 1 need to be discarded to ensure safe use of the endoscope.

The operation part 2 is approximately in a handle shape, is convenient for an operator to hold by hands and is convenient for forceful operation. The insertion section 1 includes an insertion tube 11 and a bent portion 12. The insertion tube 11 has a bent portion 12 at its distal end. From the operating portion 2, a pull wire (not shown) extends, which is drivingly connected to the bending portion 12 through the insertion tube 11. The curved portion 12 is provided with a plurality of serpentine structures rotatably connected to each other. The snake bone structure can rotate freely. The inner side wall of the snake bone structure is provided with a guide groove, and the traction wire penetrates through the guide groove to be connected with the snake bone structure in a traction manner. When the operation part 2 pulls the traction wire, the snake bone structure is driven to rotate or bend, so that the bending direction and the bending angle of the bending part 12 connected with the other end of the traction wire can be controlled. The curved portion 12 is curved to extend, and the insertion tube 11 is guided to move in the lumen.

The operation unit 2 is provided with a control knob 21. The control knob 21 is connected with the traction wire, and the control knob 21 is rotated to pull and move the traction wire. The control knob 21 may be a plurality of hand wheels. A plurality of hand wheels are coaxially arranged up and down. The finger of the operator can be used for poking.

Similarly, the operation unit 2 is provided with a control button 22. The control button 22 is in electrical communication with the pump set of the endoscope. The pump set of the endoscope is used for pumping gas or liquid and the like into the endoscope for the endoscope to use during use. The control button 22 can control the operating state of the pump unit. The working state of the pump group can comprise the switching of the pump group, the adjustment of parameters and the like.

The head end of the bending part 12 is provided with a light source and an image acquisition module. The image acquisition module is used for acquiring and obtaining image information in the cavity of the examinee. The medical staff diagnoses and treats the examinee according to the image information.

The insertion tube 11 is provided between the operation portion 2 and the bending portion 12. The insertion tube 11 has a certain flexibility to facilitate movement of the insertion tube 11 within the subject's lumen. Moreover, the outer surface of the insertion tube 11 is a smooth surface, so that on one hand, the friction force between the insertion tube 11 and the cavity can be reduced; on the other hand, the cavity of the examined person can be protected, and the examined person is prevented from being scratched.

In one embodiment, the insertion tube 11 includes a coil assembly, a braid and an outer sheath 112 disposed coaxially; the braid layer is disposed about the outside of the coil assembly and the outer skin layer 112 is disposed about the outside of the braid layer. In some cases, the braid may be omitted. In the embodiments described below, the braid and coil assembly will generally be a flexible tubular body 111. The outer sheath 112 is wrapped around the flexible pipe body 111.

FIG. 2 is a schematic structural view of an outer skin layer 112 of an endoscope insertion tube 11 according to an exemplary embodiment of the present application. Here, the outer skin layer 112 of the endoscope insertion tube 11 is tubular, and includes a rear end tube section 32 near the endoscope operation portion and a front end tube section 31 near the endoscope bending portion 12 in the axial direction of the outer skin layer 112.

In the following embodiments, an example of an extrusion device that can be used for processing the outer skin layer 112 of the endoscope insertion tube 11 will be described.

Here, the extrusion apparatus includes a molding unit 40, a pressure extrusion unit 50, and a surface treatment unit 60. The forming unit 40 has a forming passage 46 inside, and the forming passage 46 is used for the flexible pipe body 111 to travel; the forming channel 46 conforms to the shape of the flexible pipe body 111. The extruding unit is communicated with the molding passage 46, and is used for extruding the resin material into the molding passage 46, so that part of the resin material is coated on the surface of the flexible pipe body 111 to form the outer skin layer 112, and part of the resin material penetrates through the woven layer and is filled into the bending gap of the spiral pipe. The surface treatment unit 60 is communicated with the molding passage 46, and the surface treatment unit 60 is provided at a later stage of the pressure extrusion unit 50 for smoothing the surface of the resin material coated on the flexible pipe body 111.

In the present application, by providing the surface treatment unit 60, the outer skin layer 112 extrusion-molded by the extrusion unit is subjected to smoothing treatment, thereby improving the surface smoothness of the produced outer skin layer 112. And because the surface smoothness of the outer skin layer 112 is improved, the friction between the outer skin layer 112 and the resin protective sleeve on the outer layer of the insertion tube 11 is reduced, and the use frequency of the resin protective sleeve is improved.

Fig. 3 is a structural sectional view of the molding unit 40 according to an exemplary embodiment of the present application. In one embodiment of the structure of the forming unit 40, the forming unit 40 includes an inner mold 41, an outer mold 42, and at least one intermediate mold 43. A forming passage 46 is formed in the inner mold 41; the intermediate die 43 comprises a connected feed cylinder and an insert cap 432.

In this example, a first feeding passage 441 is formed between the side wall of the insertion cover 432 and the outer mold 42, and a second feeding passage 442 is formed between the side wall of the insertion cover 432 and the inner mold 41. The outer die 42 is provided with a first feeding cylinder 451, and the first feeding cylinder 451 is communicated with the first feeding channel 441; the feed cylinder of the intermediate die 43 serves as a second feed cylinder 452, and the second feed cylinder 452 communicates with the second feed passage 442. The forming unit 40 in this example has two feed channels. It will be appreciated that by providing the number of intermediate membranes, more than two feed channels may be formed.

In fig. 3, the outer surface of the inner mold 41 facing outward, the surface of the outer mold 42 facing inward, and the insertion cover 432 are each substantially in the shape of a hood with a pointed right end, and the right ends of the three are open. The resin material flowing out from the outlet of each feed passage flows in an omnidirectional manner at 360 ° to the forming passage 46, and coats the surface of the flexible pipe body 111 located in the forming passage 46. The outlets of the plurality of feed channels are arranged along the extension of the forming channel 46. Thus, as the flexible pipe body 111 passes through the forming tunnel 46, it passes through the outlet of each feed tunnel in turn.

In one embodiment, the flexible pipe 111 may travel in the molding passage 46 at a constant or variable speed, and the outlet shape of the resin material extruded into the molding passage 46 in the molding unit 40 is substantially annular to be wrapped from all directions of the flexible pipe 111.

Fig. 4 is a schematic diagram illustrating the structure of an extrusion apparatus according to an exemplary embodiment of the present application. In an embodiment, the surface treatment unit 60 includes a scraping mold 61, the scraping mold 61 includes a base and an annular scraper disposed on the base, the flexible pipe 111 covers the outer skin layer 112 and passes through the annular scraper, and the annular scraper is used for smoothing uneven portions of the surface of the outer skin layer 112.

Because the resin material is coated on the flexible pipe body 111, the outer skin layer 112 still has a certain plasticity, when the flexible pipe body 111 passes through the annular scraper, the protrusion on the outer skin layer 112 is smoothed, and the smoothed resin material is used for filling the concave part on the outer skin layer 112, so that the surface of the outer skin layer 112 is smooth.

In one embodiment, the angle between the wall of the annular scraper and the direction of extension of the forming channel 46 is 30 ° to 60 °. The outer skin layer 112 with the uneven surface of the flexible pipe body 111 can be effectively leveled at a smaller included angle, abrasion to the edge of the annular scraper is reduced, and the annular scraper can still keep a better scraping effect under long-time work. Moreover, the scraped resin material is accumulated on the blade wall of the annular scraper, so the scraped resin material can slide down along the inclined blade wall to be filled in the pits on the outer skin layer 112, and the smoothing effect on the outer skin layer 112 is improved.

Referring to fig. 5 and 9, fig. 5 is a block diagram illustrating a structure of an extrusion apparatus according to an exemplary embodiment of the present application, and a dotted line in fig. 5 indicates a traveling direction of the flexible pipe body 111. FIG. 9 is a schematic structural diagram illustrating a coil assembly according to one embodiment. The first spiral 1111 in fig. 9 is the spiral in the above embodiment. In one embodiment, the extruding unit includes a pressure extruding unit 50, and the pressure extruding unit 50 is configured to extrude the resin material in a molten state to the forming channel 46 at an extruding pressure greater than a preset pressure, and the resin material is coated on the surface of the flexible pipe body 111 to form the outer skin layer 112.

Here, the preset pressure is greater than or equal to the pressure required to fill the extruded resin material penetrating the braid into the bending gap of the first spiral tube 1111.

Based on the pressure extrusion unit 50, when the resin material can be extruded, the resin material is allowed to fill into the bending gap of the first spiral pipe 1111 wrapped in the braid through the braid. The second spiral pipe 1112 corresponding to the shape of the bending gap is formed after the resin material filled in the bending gap of the first spiral pipe 1111 is solidified. The second coil 1112 and the first coil 1111 together form a coil assembly.

In one embodiment, the pressure extrusion unit 50 includes a feed cylinder having an inlet for receiving the resin material in a molten state and an outlet in direct or indirect communication with the shaping channel 46. A pressurizing device is provided at the inlet or outlet of the feed passage for increasing the extrusion pressure of the feed cylinder to increase the pressure of the resin material into the forming passage 46, so that the resin material can penetrate the braid to fill into the bending gap of the first spiral pipe 1111, forming the second spiral pipe 1112 in the above-described spiral pipe assembly.

In another embodiment, the pressure extrusion unit 50 comprises an extruder, by which the extrusion pressure is regulated. Generally, an extruder processes a solid extrusion raw material into a molten state by heating and extruding, and then directly or indirectly extrudes a resin material into the molding passage 46 at a specific extrusion pressure or extrusion speed.

In one embodiment, there are a plurality of pressure extrusion units 50, and a plurality of pressure extrusion units 50 correspondingly extrude resin materials with various hardness, and each pressure extrusion unit 50 is correspondingly connected with one feeding channel. By adjusting the discharge sequence of the plurality of pressure extrusion units 50 as the flexible pipe body 111 travels within the forming channel 46, it is possible to achieve a softer front end section 31 and a harder rear end section 32 of the extruded outer skin layer 112.

The extrusion pressure of the pressure extrusion unit 50 is large so that the extruded resin material penetrates the braid to be filled into the bending gap of the first spiral pipe 1111 to form the second spiral pipe 1112. However, in practice, it has been found that the compression ratio of the resin material is high due to the large extrusion pressure, and the resin material exhibits the phenomena of the pits, the protrusions, and the waves due to the intermittent elastic expansion after being coated on the surface of the flexible pipe body 111. Therefore, the surface treatment unit in the present application can reduce the problem of molding smoothness caused by the use of a large extrusion pressure.

Here, the process of the surface treatment unit 60 is located after the pressure extrusion unit 50, that is, as the pipe body travels, the pressure extrusion unit 50 first coats the resin material on the flexible pipe body 111 with an extrusion pressure greater than a preset pressure to form the outer skin layer 112. At this time, the outer skin layer 112 is not yet solidified and still has plasticity. Subsequently, the flexible pipe body 111 is advanced to the surface treatment unit 60, and the surface treatment unit 60 smoothes the waviness, unevenness, and the like of the outer skin layer 112, thereby improving the surface smoothness of the outer skin layer 112 finally molded.

The pressure extruding unit 50 is provided in this application to enable the extruded resin material to penetrate the braid to be filled into the bending gap of the first spiral pipe 1111 to constitute a double spiral pipe structure with the first spiral pipe 1111. A coil assembly. The second spiral pipe 1112 formed of a resin material is soft, and the first spiral pipe 1111 made of a rigid material is hard; the soft and hard spiral tube fit allows the spiral ring of the softer second spiral tube 1112 to be disposed between the bending gaps of the spiral ring of the hard first spiral tube 1111, thereby improving the stability of torque transmission and providing a large selection space for the soft and hard disposition of the hard first spiral tube 1111. And because the flexible second spiral pipe 1112 formed by extruding the resin material is embedded in the hard first spiral pipe 1111, the spiral pipe assembly has better rotation capability and is convenient to bend and move flexibly in the detected body.

In addition, since the pressure extrusion unit 50 is adopted, the surface treatment unit 60 is further provided, and the surface treatment unit 60 further smoothes the surface of the resin material coated on the flexible pipe body 111, so that the surface defect degree of the outer skin layer 112 caused by the adoption of large extrusion pressure is reduced.

The second spiral pipe 1112 can be formed simultaneously when the outer skin layer 112 of the insertion pipe 11 is processed, the position reliability of each part inside the insertion pipe 11 is improved, the processing process is simple, and the processing efficiency is high.

Moreover, the outer skin layer 112 and the second spiral pipe 1112 formed by the processing mode are of an integrated structure, so that the stress can be mutually transmitted, and the stress can also be mutually transmitted between the second spiral pipe 1112 and the first spiral pipe 1111, so that when the insertion pipe 11 is bent, the stress on the spiral pipe assembly can be transmitted to the outer skin layer 112, and the working stability of the spiral pipe assembly is ensured.

In summary, the extrusion apparatus of the present application can simultaneously extrude the outer skin layer 112 forming the insertion tube 11 and perfect the structure of the coil assembly, and can improve the surface flatness of the outer skin layer 112. The produced insertion tube 11 has good controllability and mobility in the subject.

In one embodiment, the surface treatment unit 60 comprises an atmospheric extrusion unit; the atmospheric pressure extrusion unit is configured to extrude a resin material to the molding passage 46 at an atmospheric pressure to fill the pits formed on the surface of the outer skin layer 112. The resin material extruded at normal pressure can form a relatively smooth coating layer on the flexible pipe body 111, which will cover the uneven outer skin layer 112 previously extruded by the pressure extrusion unit 50, improving the smoothness of the surface of the finally formed outer skin layer 112.

The atmospheric extrusion unit may have the same structure as the pressure extrusion unit 50, and a pressurizing device is not required to be provided. The feeding cylinder extrudes the resin material at normal pressure. The "normal pressure" means that the extruded resin material is not subjected to pressure interference, or the resin material is extruded at a normal atmospheric pressure, or the extrusion pressure is set according to an empirical value so that the extruded resin material is coated on the flexible tube body 111 with good smoothness.

Further, the extrusion device further comprises a drying unit, wherein the drying unit is located between the pressure extrusion unit 50 and the normal pressure extrusion unit and is used for drying the outer skin layer 112 extruded and formed by the pressure extrusion unit 50, so that the outer skin layer 112 is slightly dried and solidified, and the resin material extruded by the normal pressure extrusion unit can naturally flow smoothly on the outer skin layer 112, thereby improving the smoothing effect on the outer skin layer 112.

The drying unit may be a heater, a blower, or the like disposed between the pressure extrusion unit 50 and the atmospheric extrusion unit.

In one embodiment, the spacing between the atmospheric extrusion unit and the pressure extrusion unit 50 is 20cm to 50cm, such that a drying zone is formed between the surface treatment unit 60 and the pressure extrusion unit.

This length setting can make just advance at the in-process in dry zone through extruding unit extrusion moulding's skin layer 112, can dry slightly and solidify, is favorable to subsequent ordinary pressure to extrude unit to the skin layer 112 that dry slightly solidifies, carries out smoothing processing, improves smooth effect.

It should be understood that a plurality of atmospheric pressure extrusion units 50 may be provided to smooth the surface of the outer skin layer 112 a plurality of times.

In another embodiment, the forming unit 40 has a plurality of feed channels in communication with the forming channel 46; the plurality of feeding channels are divided into pressure feeding channels and normal-pressure feeding channels, wherein the pressure feeding channels are connected with extrusion ports of the pressure extrusion units; the pressure feeding channel and the normal pressure feeding channel are sequentially arranged along the advancing direction of the flexible pipe body 111; the outlet of the normal pressure feeding passage is annular, and the flexible pipe body 111 passes through the outlet of the normal pressure feeding passage after being coated with the resin material, so that the end edge of the side wall of the outlet of the normal pressure feeding passage is formed to smooth the uneven part of the surface of the resin material coated on the flexible pipe body 111.

Referring to fig. 3 and 6, fig. 6 is a schematic structural view of the flexible pipe body 111 in the forming channel 46 according to an exemplary embodiment of the present application, and a dotted line indicates a traveling direction of the flexible pipe body 111. Here, two feeding channels are provided, and for example, when the flexible pipe body 111 is moved to the right, one feeding channel near the left side is used for communicating with the pressure extrusion unit 50 having a large extrusion pressure, and the other feeding channel near the right side is not fed. At this time, the outlet of the right feeding passage is used to form a "hoop" structure, which is hooped on the outer circumference of the flexible pipe body 111 to scrape the uneven part on the pipe section which is already coated with the resin material.

In this embodiment, the sidewall taper angle α forming the outlet of the atmospheric feed channel can be set to 30 ° -49 °; the sidewall taper angle beta forming the outlet of the pressure feed channel is 50 DEG to 80 deg. A smaller taper angle can effectively smooth out uneven portions of the surface of the formed skin layer 112.

In the related art, the outer skin layer 112 is generally formed by extruding a resin material using an extruder. The skin layer 112 thus formed is of the same hardness at different pipe sections. In the present application, a plurality of extrusion units are provided in an extrusion apparatus, the plurality of extrusion units extruding resin materials of a plurality of hardnesses correspondingly, by adjusting the discharge sequence of the plurality of extrusion units as the flexible pipe body 111 travels within the profiled passage 46, in the processing process of the outer skin 112 of the insertion tube 11, the front end tube section 31 of the outer skin 112 of the insertion tube 11 is made soft, the rear end tube section 32 is made hard, the soft and hard configuration similar to that of the spiral tube component is formed, therefore, under the condition of ensuring that the requirement on the overall flexibility of the front end pipe section 31 of the insertion pipe 11 is not changed, the scheme of the application can reduce the requirement on the flexibility of the front end pipe section 31 of the spiral pipe assembly, this allows the front end section 31 of the coil assembly to be set relatively hard, thereby ensuring that torque is stably transmitted to the foremost end of the front end section 31, and further improving the controllability of the front end section 31 of the insertion tube 11.

Specifically, in one example, the first discharge order of the plurality of extrusion units may be determined according to the order of the hardness of the resin material in the plurality of feed channels. During the process that the flexible pipe body 111 advances in the forming channel 46, the plurality of extrusion units are controlled to sequentially extrude the resin material onto the flexible pipe material in the first discharging order, so that the outer skin layer 112 formed by extrusion has a plurality of hardness sections, and the hardness of the plurality of hardness sections is sequentially increased or decreased.

Fig. 7 is a structural cross-sectional view of a forming unit 40 having a compounding area 47 according to an exemplary embodiment of the present application. In an embodiment, when there are a plurality of extrusion units, the extrusion apparatus further comprises a compounding zone 47. The mixing area 47 is communicated with the extrusion ports of the extrusion units and is communicated with the forming channel 46, and the various feeding channels enter the mixing area 47 to be mixed and then enter the forming channel 46; a mixing member is provided in the mixing area 47 to uniformly mix the resin materials of various hardnesses.

As will be understood based on the structure of the molding unit 40, the end of the insertion cover 432 of the middle mold 43 away from the feeding cylinder may be provided with a gap from the molding passage 46, so that a material mixing zone 47 is formed between the insertion cover 432, the outer mold 42 and the inner mold 41. Therefore, the resin material flowing out of the outlet of each feed channel flows to the mixing zone 47 in an omnidirectional direction of 360 °. The resin material is mixed by the mixing area 47 and then flows to the forming channel 46 gradually, and the surface of the flexible pipe body 111 in the forming channel 46 is coated with the resin material.

For the resin material used for forming the outer skin layer 112 of the endoscope insertion tube 11, the resin material in a molten state is viscous, and the hardness of the resin material entering from each feeding channel is different, so that after entering the mixing area 47, the mixing degree of the various resin materials is low, and the resin material which is not uniformly mixed is extruded on the surface of the outer skin layer 112, so that the hardness and the strength of the same cross section of the outer skin layer 112 are different, thereby affecting the transmission of torque and the flexibility of the front end tube section 31, and further causing troubles to operators using the endoscope.

Therefore, in the present embodiment, a mixing member is provided in the mixing area 47 to promote mixing of a plurality of resin materials and improve uniformity of mixing of the respective resin materials.

In an embodiment, the material mixing part is a turbulent flow structure 481 disposed in the material mixing area 47, and an extending direction of the turbulent flow structure 481 forms an included angle with a flowing direction of the resin material flowing through the turbulent flow structure 481.

Further, in order to improve the turbulent flow effect, a plurality of turbulent flow structures 481 may be disposed on both the surface of the outer mold 42 and the surface of the inner mold 41.

In one embodiment, the spoiler structure 481 is plate-shaped and curved. The arc-shaped turbulent flow structure 481 has certain guidance for the resin material, and can change the flow direction of the resin material flowing through the turbulent flow structure 481 to a greater extent, so that turbulent flow is formed between the resin materials, and the degree of mixing between the resin materials is promoted.

Fig. 8 is a schematic view of a mixing bowl 471, a mixing channel 472, etc., shown in accordance with an example embodiment of the present application. In another embodiment with respect to the mixing member, the extrusion device includes a mixing bowl 471, a plurality of feed guides 4771 disposed on the mixing bowl 471, and a mixing tube disposed on the underside of the mixing bowl 471; a mixing region 47 is formed in the mixing bin 471, a feeding channel is formed in the feeding guide structure 4771, and a mixed flow channel 472 is formed in the mixed flow pipe.

The mixing member is a stirring structure 482 arranged in the mixing area 47, and the stirring structure 482 rotates and mixes resin materials with various hardness in the mixing area 47; the extrusion device further comprises a flow mixing channel 472 communicating with the outlet of the mixing silo 471, the outlet of the flow mixing channel 472 communicating with the shaping channel 46.

In this embodiment, the stirring structure 482 may include a stirring rod having a propeller structure thereon to stir-mix the plurality of resin materials in the mixing zone 47. The stirring structure 482 may be configured with a driving member, such as a motor, a cylinder, etc., to drive the stirring rod to rotate and control the rotation speed of the stirring rod, so as to adaptively adjust the rotation speed of the stirring rod according to the amount of the resin material and the type of the resin material in the material mixing area 47, thereby improving the uniformity of material mixing.

Also, in this embodiment, the stirring structure 482 performs primary mixing, and the mixing channel 472 performs secondary mixing. The mixing channel 472 is elongated. In one aspect, the elongated configuration of the mixing channel 472 can further promote mixing between the resin materials. On the other hand, the resin material speed after the stirring structure 482 mixes is very fast, and the mixed flow passageway 472 can adjust resin material's speed and pressure, and the speed is very fast when avoiding the cladding of resin material on flexible pipe body 111, and produces the ripple, influences and extrudes the quality.

In one embodiment, the mixing channel 472 is curved, and the resin material moves in a curve in the mixing channel 472. Specifically, the mixing channel 472 is helical. The helical structure can carry out the flow distance of great extension resin material with less volume, improves the compounding effect.

The export of mixed flow pipe can be connected to a mould, has the water conservancy diversion passageway that is the tube-shape in this mould, and this water conservancy diversion passageway extends along left right direction, and the right side narrows down gradually, and the right-hand member portion of water conservancy diversion passageway is uncovered, and communicates with shaping passageway 46, and the resin material that consequently the export of water conservancy diversion passageway flows out is at the periphery wall of flexible body 111 with 360 omnidirectional cladding. As the flexible pipe body 111 travels within the molding passage 46, the resin material flowing out of the annular mouth of the feed passage coats the entire outer peripheral surface of the flexible pipe body 111.

In the above embodiment, the extrusion unit is plural. In the following examples, one extrusion unit is exemplified.

In one embodiment, one of the extrusion units, the extrusion apparatus further includes a retractor disposed at one side of the forming channel 46; the tractor serves to regulate the traveling speed of the flexible pipe body 111 within the forming passage 46 to be gradually reduced during the extrusion of the resin material by the extrusion unit, so that the thickness of the outer skin layer 112 formed by extrusion is gradually increased.

It should be understood that in the case of a constant extrusion speed, the smaller the traveling speed of the flexible pipe body 111, the greater the amount of resin material coated on the surface of the flexible pipe body 111 in the pipe body length direction. The traveling speed of the flexible pipe body 111 is gradually reduced and the thickness of the outer skin layer 112 correspondingly formed is gradually changed from thick to thin.

As described above, when the pressure extruding unit 50 extrudes the resin material at a large pressure, the resin material may be forced under pressure into the tube of the first spiral tube 1111, thereby affecting the normal installation of the endoscope guide wire, the instrument tube, and the air water path.

Here, the extrusion device further includes a centering mold 70, and the centering mold 70 is configured to extend into the flexible pipe body 111 and tightly fit with the flexible pipe body 111. The centering die 70 travels with the flexible pipe body 111 within the forming channel 46.

Here, "tight fit" means that a certain tooling pressure is provided between the centering die 70 and the flexible pipe body 111 to minimize a gap between an outer surface of the centering die 70 and an inner surface of the flexible pipe body 111. Therefore, during the extrusion process, even if the extrusion pressure of the pressure extrusion unit 50 is excessively large, the resin material is stopped at the centering die 70 without entering into the tube of the flexible tube body 111, so that the resin material can be uniformly filled in the bending gap of the first spiral tube 1111.

After the extrusion is completed, in order to facilitate the removal of the centering die 70 from the flexible pipe body 111, the centering die may be provided as an inflation die which facilitates the removal from the flexible pipe body 111 by deflating to reduce the volume.

In another embodiment, it may be further provided that the surface of the centering die is coated with a non-stick coating to repel the resin material. Therefore, after the extrusion is completed, the centering die 70 is withdrawn without being subjected to the viscous force of the resin material, and the structural stability of the extruded outer skin layer 112 and the coil assembly is ensured.

In the following examples, examples of the outer skin layer 112 of the insertion tube 11 of the present application will be described. By using the extrusion apparatus in the above embodiment, the outer skin layer 112 having a smooth surface can be processed, and the hardness of the rear end pipe section 32 of the outer skin layer 112 can be made greater than that of the front end pipe section 31.

Specifically, in one embodiment, the endoscope insertion tube 11 and the outer skin layer 112 are tubular and include a rear end tube section 32 near the endoscope operation portion 2 and a front end tube section 31 near the endoscope bending portion 12 in the axial direction of the outer skin layer 112.

The front and

rear sections

31, 32 are understood to mean the sections near the front end of the insertion tube 11 and the sections near the rear end of the insertion tube 11. The lengths of the front and

rear pipe sections

31 and 32 are not necessarily equal. It will also be understood that the entire insertion tube 11 is composed of a front end tube section 31 and a rear end tube section 32 in this order. The front end section 31 of the insertion tube 11 includes the front end section 31 having the outer sheath 112, the front end section 31 of the braid, and the front end section 31 of the helical tube assembly. The rear end section 32 of the insert tube 11 also includes the rear end section 32 having the outer skin 112, the rear end section 32 of the braid, and the rear end section 32 of the coil assembly. In some embodiments, the entire insertion tube 11 is made up of, in order, a front end tube section 31, a middle tube section, and a rear end tube section 32; the hardness of the intermediate section is between the hardness of the front section 31 and the hardness of the rear section 32.

In the following embodiments, examples of the coil assembly of the present application will be explained. By using the extrusion apparatus in the above-described embodiment, it is possible to manufacture the outer skin layer 112 for wrapping the spiral tube assembly in the following embodiments, or to manufacture the second spiral tube 1112 and the outer skin layer 112 in the spiral tube assembly.

The coil assembly has a rear end pipe section 32 near the endoscope operating section 2, and a front end pipe section 31 near the endoscope bending section 12; the spiral pipe assembly comprises a plurality of spiral pipes which are coaxially arranged and have the same spiral direction; a plurality of spiral pipes spirally extend from the rear end pipe section 32 to the front end pipe section 31 in parallel; the plurality of coils are of different hardness from one another and the hardness of the rear section 32 of at least one coil is greater than the hardness of the front section 31 of that coil such that the hardness of the rear section 32 of the coil assembly is greater than the hardness of the front section 31 of the coil assembly.

In one example, the plurality of spiral pipes may be arranged in parallel in the axial direction of the spiral pipe assembly, illustratively, the spiral pipe is formed by a plurality of strips having a certain width by means of spiral, the plurality of strips are arranged in sequence in the axial direction of the spiral pipe assembly in the width direction thereof before the spiral is not formed, and then the plurality of strips extend in a spirally surrounding manner in the front-rear direction together to form a case where the plurality of spiral pipes extend spirally in parallel.

In another example, a plurality of strips are stacked in the radial direction of the coil assembly, and thereafter, the plurality of strips collectively extend in a spirally circulating manner in the front-rear direction to form a case where a plurality of coils extend spirally in parallel.

Referring to fig. 9, fig. 9 is a schematic structural diagram of a coil assembly according to an embodiment. In a particular embodiment, the coil assembly includes a first coil 1111 and a second coil 1112, the first coil 1111 having a hardness greater than the second coil 1112, the first coil 1111 including a plurality of consecutive first coil loops, the second coil 1112 including a plurality of consecutive second coil loops; a bending gap is formed between every two adjacent first spiral rings; wherein the second spiral rings of the second spiral pipe 1112 are disposed in the bending gaps of the first spiral rings of the first spiral pipe 1111 in a one-to-one correspondence.

In particular, the bending gap is present between the end edges of adjacent first helical rings, it being understood that the bending gap as a whole is also substantially helical. The second coil 1112 is fittingly disposed in the bending gap to form a double spiral structure with the first coil 1111.

In one embodiment, the width of each bending gap in the front end section 31 of the first spiral pipe 1111 in the axial direction of the first spiral pipe 1111 is greater than the width of each bending gap in the rear end section 32 of the first spiral pipe 1111.

Referring to fig. 10, fig. 10 is a schematic structural diagram of another coil assembly according to an embodiment. In one embodiment, the bending gap of the first spiral tube 1111 increases in sequence from the rear end toward the front end.

In one embodiment, for the first coil 1111, the wall thickness of the first coil loop in the rear section 32 is greater than the wall thickness of the first coil loop in the front section 31.

In one embodiment, the wall thickness of the first helical ring decreases in a direction from the rear end toward the front end.

Referring to fig. 11, fig. 11 is a schematic structural diagram of another coil assembly according to an embodiment. In one embodiment, for the first coil 1111, the width of the first coil loop in the rear section 32 is greater than the width of the first coil loop in the front section 31.

In one embodiment, the hardness of the front section 31 of the second coil 1112 is less than the hardness of the rear section 32 of the second coil 1112.

In one embodiment, the second coil 1112 is made of a resin material including a composition of one or more of TPU (Thermoplastic polyurethane elastomers), polyester, nylon, rubber, or silicone.

In the present application, the coil assembly is formed by a plurality of coils with different hardness, wherein the hardness of the rear end section 32 of at least one coil is greater than that of the front end section 31 of the coil, so that the hardness of the rear end section 32 of the coil assembly is greater than that of the front end section 31 of the coil assembly; the harder rear end tube section 32 facilitates torque transfer to the front end tube section 31, and the softer front end tube section 31 can facilitate flexible bending within the subject.

In addition, in the present application, the plurality of spiral pipes are arranged in parallel, so that the transmission of torque from the rear pipe section 32 to the front pipe section 31 is further facilitated, the controllability of the front pipe section 31 of the insertion pipe 11 is improved, and the operation reliability of the insertion pipe 11 is improved.

In conclusion, the present application achieves both reliability in handling the insertion tube 11 and flexibility in movement of the insertion tube 11.

In order to realize the structure of the coil assembly, in the manufacturing process, the first coil 1111 is firstly processed, wherein the first coil 1111 has a plurality of continuous first coil rings, and a bending gap is formed between two adjacent first coil rings along the axial direction of the first coil rings; then, a braid is processed at the outer side of the first spiral pipe 1111; finally, a resin material is injected into the bending gap of every two adjacent first spiral rings in the first spiral pipe 1111 through the woven layer by using an extrusion device to form a second spiral pipe 1112 through extrusion; the first coil 1111 and the second coil 1112 are of different hardness and the rear section 32 is harder than the front section 31 for at least one of the first coil 1111 and the second coil 1112 such that the hardness of the coil assembly rear section 32 is greater than the hardness of the coil assembly front section 31.

While the present application has been described with reference to several exemplary embodiments, it is understood that the terminology used is intended to be in the nature of words of description and illustration, rather than of limitation. As the present application may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.

Claims

1. An extrusion device for processing an outer skin layer of an endoscope insertion tube, wherein the endoscope insertion tube comprises an outer skin layer and a flexible tube body, the flexible tube body comprises a spiral tube and a woven layer sleeved outside the spiral tube, and the outer skin layer is coated outside the woven layer; characterized in that the extrusion device comprises:

the surface treatment unit is communicated with the forming channel and is used for smoothing the surface of the outer skin layer coated on the flexible pipe body;

the surface treatment unit comprises a scraping mould, the scraping mould comprises a base and an annular scraper arranged on the base, and the annular scraper is used for smoothing uneven parts of the surface of the outer skin layer; the included angle between the knife wall of the annular scraper and the extension direction of the forming channel is 30-60 degrees; or

The extrusion unit comprises a pressure extrusion unit, the pressure extrusion unit is used for extruding a resin material in a molten state to the forming channel at an extrusion pressure greater than a preset pressure, and the resin material is coated on the surface of the flexible pipe body to form the outer skin layer; the preset pressure is greater than or equal to the pressure required for enabling the resin material to penetrate through the woven layer to be filled into the bending clearance of the spiral pipe; the forming unit has a plurality of feed channels in communication with the forming channel; the feeding channels are divided into pressure feeding channels and normal-pressure feeding channels, wherein the pressure feeding channels are connected with extrusion ports of the pressure extrusion units; the pressure feeding channel and the normal-pressure feeding channel are sequentially arranged along the advancing direction of the flexible pipe body; the outlet of the normal-pressure feeding channel is annular, the flexible pipe body is coated with the resin material and then penetrates through the outlet of the normal-pressure feeding channel, and the end edge of the side wall of the outlet of the normal-pressure feeding channel is formed and used for smoothing uneven parts of the surface of the resin material coated on the flexible pipe body; the taper angle of the side wall forming the outlet of the normal-pressure feeding channel is 30-49 degrees; the angle of taper of the side wall forming the outlet of the pressure feed channel is 50 DEG to 80 deg.

2. The extrusion apparatus of claim 1, wherein the surface treatment unit comprises an atmospheric extrusion unit;

3. The extrusion apparatus of claim 2, further comprising a drying unit disposed between the pressure extrusion unit and the atmospheric extrusion unit for drying the outer skin layer extruded by the pressure extrusion unit.

4. The extrusion apparatus of claim 2, wherein the distance between the pressure extrusion unit and the atmospheric extrusion unit is 20cm-50 cm.

5. The extrusion apparatus according to claim 1, wherein the extrusion unit is plural, and plural extrusion units correspondingly extrude resin materials of plural hardnesses to the forming passage;

when the flexible pipe body moves in the forming channel, the front end pipe section and the rear end pipe section of the outer skin layer formed by extrusion are softer and harder by adjusting the discharging sequence of the extrusion units.

6. The extrusion apparatus of claim 5, further comprising a compounding zone;

7. The extrusion apparatus of claim 1, further comprising a retractor disposed to one side of the shaping channel;

in the process that the extrusion unit extrudes the resin material, the tractor is used for regulating and controlling the advancing speed of the flexible pipe body to be gradually reduced so as to enable the thickness of the outer skin layer formed by extrusion to be gradually increased.

8. The extrusion apparatus as claimed in claim 1, further comprising a centering die, wherein the centering die is axially inserted into the flexible pipe body and is tightly fitted with the flexible pipe body.