The present invention relates to a minimally invasive surgical instrument, and in particular, to a trocar sealing element.
A trocar is a surgical instrument, that is used to establish an artificial access in minimally invasive surgery (especially in rigid endoscopy). Trocars comprise in general a cannula and an obturator. The surgical use of trocars generally known as: first make the initial skin incision at the trocar insertion site, then insert the obturator into the cannula, and then together they facilitated penetration of the abdominal wall through incision into the body cavity. Once penetrated into the body cavity, the obturator is removed, and the cannula will be left as access for the instrument get in/out of the body cavity.
In rigid endoscopy surgery, it is usually necessary to establish and maintain a stable pneumoperitoneum for the sufficient surgical operation space. The cannula comprises a sleeve, an outer body, a seal membrane (also known as instrument seal) and a duck bill (also known as closure valve). Said cannula providing a channel for the instrumentation in/out of the, body cavity, said outer body connecting the sleeve, the duck bill and the seal membrane into a sealing system; said, duck bill normally not providing sealing for the inserted instrument, but automatically closing and forming a seal when the instrument is removed; said seal membrane accomplishing a gas-tight seal against the instrument when it is inserted.
In a typical endoscopic procedure, it is usually set up 4 trocars (access), i.e. 2 sets of small diameter cannula (normally 5 mm in diameter), and 2 sets of large diameter cannula (normally 10-12 mm in diameter). Instruments, in general passing through a small cannula are only for ancillary works; herein one large cannula as an endoscope channel, and the other large cannula as the main channel for surgeon to perform surgical procedures. Through said main channel thereof, 5 mm diameter instruments used in approximately 80% of the procedure, and said large cannula used in approximately 20% of the procedure; furthermore, 5 mm instruments and large diameter instruments need to be switched frequently. The small instruments are mostly used, so that the sealing reliability of which is more important. The large instruments are more preferably used in a critical stage of surgery (Such as vascular closure and tissue suturing), therein switching convenience and operational comfort are more important.
As illustrated in
As illustrated in
As illustrated in
The instrument inserted into the sealing membrane and moved during surgical procedure, there is large frictional resistance between the wrapped area and the inserted instrument. Said large frictional resistance is normally easy to cause the, seal inversion, poor comfort of performance, fatigue performance, even result in cannula insecurely fixed on the patient's abdominal wall etc., such that the performance of cannula assembly is affected.
Among the defects caused by the large frictional resistance, the seal inversion is one of the most serious problems that affecting the performance of the cannula. As illustrated in
The simplest way to reduce the frictional resistance is reducing the coefficient of friction between the two contacting surfaces with grease, but the reliability of this way is not good. During procedures, due to instruments long-term repeated scraping with the seal membrane and repeated switching, it is easy to erase the grease off and carried away, resulting in bad lubrication.
A protector assembly adjoined by a seal membrane is disclosed in U.S. Pat. No. 5,342,315. Said protector to permit the sharp edge of the instrument to pass through the opening in the seal membrane without causing damage to the seal membrane, and the surface friction coefficient of the protector assembly is smaller than the surface friction coefficient of the seal membrane, which results in less frictional drag, but the lip-adjacent area is normally not completely covered by the protector assembly.
A seal member with ribs (or projections) is disclosed in U.S. Pat. No. 5,827,228, that is a plurality of spaced ribs provided to extend outwardly from center hole to reduce surface contact between the inserted instrument and the seal member, and thereby reducing the frictional resistance, a similar ribs which disclosed in EP0994740 also reducing surface contact and strengthen the tensile of the seal member oriented to axial.
A sealing element comprising a flexible wall closed annularly with the edges foldable in a wave-like manner is disclosed in U.S. Pat. No. 7,842,014, wherein the wall bears a wave-like sealing lip and is a wavy pleated seal body, in such manner it can enlarge hoop circumference, and reduce the hoop force to a certain extent.
Chinese invention application CN101480354A (currently rejected) discloses a seal member containing an easily deformable groove, wherein is characterized in that it has a plurality of easily deformable grooves on the conical surface of the seal member from the sealing lip; said the thickness of the deformable groove wall is much smaller than the thickness of the conical surface wall, primary take advantage of the elongation of the deformable groove to accommodate the inserted large diameter instrument.
Although, in the prior art many solutions for reducing the frictional resistance have been disclosed, these solutions basically only propose measures from one certain factor affecting frictional resistance, the effect of which is small or not obvious. Some modifications solved a certain defects may lead to cause another bug. Such as, reinforcing ribs on the seal membrane to reduce surface contact, meanwhile strengthen the tensile of the seal membrane; or a deformable groove with a thickness much smaller than that of a truncated conical surface can cause the deformable groove to be easily damaged; due to the adoption of said wave-like sealing lip which enlarge hoop circumference, the sealing reliability will be sacrificed when a 5a mm diameter instrument is inserted, if the wave-like sealing lip is used but without enlarge hoop circumference, the wave-like sealing lip will lose its improvement effect. In summary there are many factors affecting the frictional resistance, and the comprehensive effects of various factors must be considered in the perspective of mechanics and tribology.
The seal membrane is preferably produced from rubber such as natural rubber, silicone or polyisoprene, its mechanical properties including super elastic and viscoelastic. Although the mechanical model of the rubber deformation process is complicated, it can still apply the generalized Hooke's law to describe approximatively its elastic behavior; and Newton's internal friction law to describe the viscous behavior. Research suggests that the main factors affecting the friction of the two surfaces in contact between the rubber and the instrument include: the smaller the friction coefficient of said two surfaces, the smaller the friction is; the better lubrication condition of said two surfaces in contact, the friction smaller is; the smaller normal pressure of said two surfaces, the friction smaller is. Comprehensively considering the above factors, the present invention proposes better solutions for reducing the frictional resistance between the seal membrane and the inserted instrument.
In addition to said frictional resistance greatly affecting the performance of the cannula assembly, the stick-slip of the seal membrane is another main factor affecting the performance of trocar. Said stick-slip means that when the instrument moves longitudinally in the sleeve, the sealing lip and lip-adjacent area sometimes are relatively statically attached to the instrument (at this point, the friction between the instrument and the seal membrane is mainly static friction.); but sometimes it produced a relatively slippery phenomenon with the instrument (at this point, the friction between the instrument and the seal membrane is mainly dynamic friction.); and said static friction is much greater than said dynamic friction. The two frictions alternately occur, which causes the movement resistance and speed of the instrument in the seal membrane to be unstable. It is easy to be understood for those skilled in the art, that in minimally invasive surgery the surgeon can only use surgical instruments to touch (feel) the patient's organs and observe a part of the working head of the instruments through endoscopic image system. In this case where the vision is limited and it cannot be touched, the surgeon typically uses the feedback of the resistance when moving instruments as one of the information to judge whether the operation is abnormal nor not. The stick-slip affects the comfort of operation, the accuracy of positioning, and even induces the surgeon to make false judgment.
During the surgical application of the cannula, the stick-slip is difficult to avoid, but can be, reduced. Researches have shown that said stick-slip is affected by two main factors: one is that the smaller the difference between the maximum static friction and the dynamic friction, the weaker the stick-slip is; the other is that the larger the axial tensile stiffness of the seal membrane, the weaker the stick-slip is. Avoiding excessive the hoop force between the seal membrane and the instrument, reducing the two surfaces contacted, maintaining good lubrication, respectively, can reduce the difference between the maximum static friction and the dynamic friction, thereby reducing stick-slip, meanwhile, increasing the axial tensile stiffness of the seal membrane also helps to reduce the stick-slip phenomenon. The invention also proposes measures for improving stick-slip.
In summary, so far, there is no cannula that can effectively solve the said problems.
One object of the invention is to solve the problem of the seal inversion from another perspective: take measures to reduce the probability of the seal inversion, at the same time, completely solve the problem of complete jam, and take measures to reduce frictional resistance and improve comfort of performance after inversion.
To design an integral invertible trocar seal assembly need to solve two major hazards caused by the inversion of the seal membrane described in the background of the invention. One of the main hazards caused by the inversion of the seal membrane is that the elastic material accumulates between the instrument and the floating ring (the center hole of the outer body) abject to the seal membrane, resulting in blockage, the occurrence of which hazard is mainly due to the lack of reserved clearance for inversion In one aspect of the present invention, designing a seal system for trocar: includes an upper body, a lower body, a center hole axially aligned with said upper body and said lower body, also includes a seal membrane assembly mounted between said upper body and said lower body. Said seal membrane assembly comprises a seal membrane, a protection device, the first retainer ring and the second retainer ring. Said seal membrane comprises a distal aperture, an inner seal body, a flange, an outer floating portion and a proximal end. Said protection device comprises a flange and a protector said seal membrane and said protect device are sandwiched between the first retainer ring and the second retainer ring, and one side of the flange of said protection device is in close contact with the flange of said seal membrane, while the other side in close contact with the first retainer ring. The geometric size of said first retainer ring conforms to the following equation:
R
i
≥R
in
+T
s
+T
p+δ
H≥H
s
+ΔL
Another main hazard caused by the, inversion of the seal membrane is that it causes iction to abnormally increase and unstable the instrument when moving out from the patient's body, and affect the comfort of use. There are two main factors: first, the function of the protector after the inversion is completely lost, the wrapped area on the back of the instrument and the seal membrane increases, which leads to frictional resistance increased; second, the large frictional resistance after inversion is prone to “stick-slip” phenomenon.
Therefore, it is necessary to design a trocar seal membrane, which comprises a proximal opening, a distal aperture, and a sealing wall from the distal aperture extending, to the proximal opening, said distal aperture formed by a sealing lip for accommodating the inserted instrument arid forming a gas-tight seal. Said the sealing wall includes a proximal surface and a distal surface. Said seal membrane can ensure a reliable seal for the inserted 5 mm instrument, and reduce frictional resistance and improve stick-slip when a large-diameter instrument is inserted.
As described in the background, the wrapped area formed by the sealing lip and the lip-adjacent area when a large diameter instrument inserted, is the major factor cause of frictional resistance. For reducing said frictional resistance, comprehensive consideration should be given such as reducing the radial stress between the instrument and the seal membrane, reducing said wrapped area, and reducing the actual contact area of the two surfaces. It is easy to understand for those skilled, in the art that in accordance with the generalized Hooke's law and Poisson effect, enlarge hoop circumference, and reduce hoop strain (stress), thereby reducing radial strain (stress). But it should be noted that it is impossible to enlarging the hoop circumference in order to reduce the strain of the sealing lip which will result in reduced sealing reliability when applying 5 mm instruments. Since the stress in the lip-adjacent area is highly concentrated when applying a large diameter instrument, the hoop circumference of the lip-adjacent area should be rapidly increased. In regard to outside the lip-adjacent area, since the, strain (stress) is small, it is not necessary to adopt measures to enlarge the hoop circumference. In, addition, enlarging the hoop circumference, in the meantime increasing the axial tensile stiffness in the lip-adjacent area and maintain good lubrication (reducing difference between the maximum static friction and dynamic friction), thereby the stick-slip in the lip-adjacent area is improved.
In one aspect of the present invention, said seal membrane comprises a proximal opening, a distal aperture, and a sealing wall from the distal aperture extending to the proximal opening, said sealing wall with a proximal surface and a distal surface, said distal aperture formed by a sealing lip for accommodating the inserted instrument forms a gas-tight seal, said sealing wall in the lip-adjacent area, is a seamless sealing body with a plurality of normal concave-channels and a plurality of reverse concave-channels surrounding the sealing lip in an alternating manner. Said normal concave-channels are recessed from the distal surface of the sealing wall toward the proximal surface and the opening oriented to the distal surface. The shape of the normal concave-channels from the perspective of distal surface is represented as a hollow convex-rib that is raised from the distal surface. Said normal concave-channels extend laterally outward from the sealing lip, and the depth of said concave-channels gradually increases in the lip-adjacent area; while the depth of said concave-channels gradually decreases outside the lip-adjacent area. In the lip-adjacent area, said seal membrane includes 8 normal concave-channels with the approximately U-shaped section and 8 reverse concave-channels with the approximately U-shaped section. Said seal membrane includes a flange at which the sealing wall extendedly intersects, or simultaneously the sealing wall and said concave-channels extendedly intersect, and an outer floating portion including at least one lateral pleat extending from the flange to the proximal opening.
Said the seal membrane with concave-channels has the functions of enlarging hoop circumference, reducing the wrapped area, reducing the actual contact area of the two surfaces between the instrument and the seal membrane, improving lubrication reliability, increasing the axial tensile stiffness, etc., thereby, the frictional resistance and the stick-slip can be greatly reduced, and the probability of inversion is reduced and the comfort of application is improved. While said concave-channels, the depth of which gradually increases in the lip-adjacent area; while the depth of which gradually decreases, outside the lip-adjacent area, which can simplify mould design, improve the efficiency of the seal membrane processing; reduce the space occupied by the lateral movement of the seal membrane assembly, so that the size of trocar can be designed to be smaller; reduce the material accumulation between the seal membrane and the instrument after inversion and the actual contact area of the two surfaces.
In another aspect of the present invention, said seal membrane comprises a proximal opening, a distal aperture, and a sealing wall from the distal aperture extending to the proximal opening, said sealing wall with a proximal surface and a distal surface, said sealing wall in the lip-adjacent area, is a seamless sealing body with a plurality of normal concave-channel and a plurality of reverse concave-channel surrounding the sealing lip in an alternating manner. Said normal concave-channel is recessed from the proximal surface of the sealing wall toward the distal surface and the opening oriented to the proximal surface. The shape of the normal concave-channel from the perspective of distal surface is represented as a hollow convex-rib that is raised from the distal surface. Said normal concave-channel includes two side sealing-walls and an outer sealing-wall defined by the two side sealing-walls, said outer sealing-wall has a proximal surface and a distal surface, and said outer sealing-wall includes solid-rib rising to the distal surface. In an alternative embodiment, said normal concave-channel has U-shaped solid-rib rising from the bottom of the concave-channel toward the distal surface. In another alternative embodiment, said normal concave-channel has rectangular solid-rib rising from the bottom of the concave-channel toward the distal surface. The main function of said U-shaped solid-rib or rectangular solid-rib is: when inversion happened, the raised solid-rib reduces surface direct contact between the instrument and the inverted seal membrane, thereby reducing the frictional resistance. At the same time, the recessed area between the solid-ribs has a certain role in storing grease. When the seal membrane is turned over, the friction between the instrument and the seal membrane, first take away the grease on the raised solid-ribs, while the grease in the recessed area between the solid-ribs can be added to the surface of the solid-rib as the instrument moves, thereby improve lubrication reliability in a certain degree after inversion. However, arbitrary solid-rib cannot extend to the sealing lip, it should be kept away from the sealing lip as, much as possible to prevent from increasing the hoop force in adjacent areas.
It is believed that the above invention or other objects, features and advantages, will be understood with the drawings and detailed description.
A more complete appreciation of this invention and many of the attendant advantages thereof will be readily apparent as the same becomes better understood by reference to the following detailed description, where:
Embodiments of the invention are disclosed herein, however, it should be understood that the disclosed embodiments are merely examples of the invention, which may be implemented in different ways. Therefore, the invention is not intended to be limited to the detail shown, rather, it is only considered as the basis of the claims and the basis for teaching those skilled in the art how to use the invention.
Said seal membrane 130 includes a proximal opening 132, a distal end aperture 133, and the sealing wall extending from the distal end to the proximal end, said sealing wall including a proximal surface and a distal surface. Said aperture 133 formed by a sealing lip 134 for accommodating an inserted instrument and forming a gas-tight, seal. Said sealing lip 134, in the present embodiment, is approximately circular, but said sealing lip 134 may be non-circular.
Said the seal membrane 130 also including the flange 136; The sealing wall 135 has one end connected to the sealing lip 134 and the other end connected to the flange 136; the floating portion 137 has one end connected to the flange 136 and the other end connected to said proximal end 132. Said flange 136 for mounting the protector device 160. Said floating portion 137 including one or several plurality of radial (lateral) pleats, so that the entire seal membrane assembly 180 can float in the assembly 200.
Said assembly 180 can be made from a variety of materials with a range of different properties. For instance, said seal membrane 130 is made of, a super elastic material such as silicone or polyisoprene; said protector device 160 is made of a semi-rigid thermoplastic elastomer; and said second retainer ring 120 and said first retainer ring 170 are made of a relatively hard rigid material such as polycarbonate.
An Integral invertible trocar seal assembly need to solve the, two major hazards caused by the inversion of the seal membrane described in the background of the invention. One of the main hazards caused by the inversion of the seal membrane is that the elastic material accumulates between the instrument and the floating ring (the center hole of the outer body) abject to the seal membrane, resulting in blockage, the occurrence of which hazard is, mainly due to the lack of reserved clearance for inversion. In one aspect of the present invention, by increasing the inner diameter of the center hole 173 of the first retainer ring 170, a sufficient inversion space, is reserved to ensure that, the sealing membrane does not become stacked into blocked between the first retainer ring and the instrument after the seal membrane inversion. It will be understood by those skilled in the art, the inner diameter of the proximal hole 193 of the upper body 190 cannot be increased. Since the inner diameter of the proximal hole 193 is increased, it is inevitable that when a 5 mm diameter instrument is inserted, the lateral movement space of the instrument is increased, resulting in a decrease in sealing reliability. Therefore, the inverted seal membrane should be prevented from entering the, proximal hole 193.
One of the simple methods is to increase the height of the first retainer ring 170, and completely limit the inverted seal membrane in the central hole 173 of the first retainer ring. Those skilled in the art readily conceive that the end surface 194 of the proximal hole 193, and the maximum diameter thereof should be larger than the inner diameter of the center hole 173 to prevent the end surface 194 from falling into the center hole 173. Those skilled in the art readily conceive that said end surface 194 can be a complete curved surface or be constructed of a series of discontinuous ribs (in order to prevent injection shrinkage).
Optionally, said first retainer ring conforms to the following equation:
R
i
≥R
in
+T
s
+T
p+δ
H≥H
s
+ΔL
Normally the thickness of the sealing wall 135 is 0.5˜0.8 mm, the thickness of protector 163 0.1˜0.3 mm, reserved clearance δ is usually twice as thick as the sealing wall 135, e.g. δ≥1 mm. Elongation of a frustum section of the seal membrane when working ΔL is defined by the structure and size of the sealing wall 135 of the seal membrane itself, for example, different thickness of the sealing wall 135, different elongation ΔL.
Another main hazard caused by the inversion of the seal membrane is that it causes friction to abnormally increase and unstable the instrument when moving out from the patient's body, and affect the comfort of use. There are two main factors: first, the function of the protector after the inversion is completely lost, the wrapped area on the back of the instrument and the seal membrane increases, which leads to frictional resistance increased; second, the large frictional resistance after inversion is prone to “stick-slip” phenomenon.
Defining the axis of said sealing lip 134 as the longitudinal axis 158, and a transverse plane 159 that is generally perpendicular to the longitudinal axis 158. Said sealing wall 135, which can be approximately frustum, approximately hemispherical, or an irregularly rotating surface. In, this embodiment said wall 135 is formed in an approximately conical arrangement surrounding the sealing lip 134. Said wall 135 including an inner sealing-wall 141, an outer sealing-wall 142 and a side sealing-wall 143. Said inner sealing-wall 141 extends laterally from the sealing lip 134 to the flange 136; said an outer sealing-wall 142 extends laterally from the sealing lip 134 to tilted-sealing-wall 144; while said tilted-sealing-wall 144 and said inner sealing-wall 141(or the flange 136) are intersected. The first side of said side sealing-wall 143 intersects the inner sealing-wall 141 and form a line 145a, 145b; the second side of said side sealing-wall 143 intersects the outer sealing-wall 142 to form a line 146a, 146b; the third side of said side sealing-wall 143 intersects the tilted-sealing-wall 144 to form a line of intersection 147a, 147b. One end of said tilted-sealing-wall 144 intersects the outer sealing-wall 142 to form a line 148a, 148b; the other end of said tilted-sealing-wall 144 intersects the inner sealing-wall 141 to form a line 149a, 149b.
Referring to
Defining the angle between said intersection line 145a (145b) and said transverse plane surface 259 as a, which is called the guide angle α. The angle formed by the intersection lines 145a and 146a (or 145b and 146b) is defined as θ. The intersection of the two intersection lines (i.e. the apex of the angle θ) may be on the sealing lip 134; or the virtual extension lines of the two intersection lines intersect the inside of the sealing lip 134.The angle formed by the intersection lines 145a and 147a (or 145b and 147b) is defined as β. In the lip-adjacent area, the side sealing-wall 143 is a surface defined by both sides and extending laterally outward from the sealing lip 134 and gradually widening; while outside the lip-adjacent area, said side sealing-wall 143 is a tapered region defined by the edges, said side sealing-wall 143 is approximately obtuse triangular near the boundary of the lip-adjacent area. That is, when said normal concave-channel 140 extending laterally outward, the depth of it gradually increases in the lip-adjacent area, while gradually decreases outside the lip-adjacent area. Moreover, the 2 adjacent side walls 143 and the inner sealing-wall 141 there between only a distinct reverse concave-channel is formed in the lip-adjacent area, while no distinct reverse concave-channel is formed outside the lip-adjacent area. From the perspective of the distal surface, said normal concave-channel 140 is shaped as a hollow convex-rib that is raised on the distal surface. Said hollow convex-rib extends laterally outward from the sealing lip and gradually increase in height, and abrupt change occurs near the boundary of the lip-adjacent area, and the height thereof rapidly decreases.
The sealing wall 135 in the present embodiment, comprises 8 linear normal concave-channels and 8 reverse concave-channels, however, a greater number or a smaller number of non-linear reverse concave-channel may be adopted. The side sealing-wall 143 of the present embodiment is substantially parallel to the longitudinal, axis 158, and in the lip-adjacent area, make a arbitrarily section plane that parallel to said axis 158 and meanwhile perpendicular to any one of said side sealing-walls 143, the intersected profile formed by said section plane and said concave-channels 140 and reverse concave-channels 150 is approximately U-shaped (the intersected profiles of other concave-channels are also defined in this way). That is, the section of the normal concave-channel 140 or the reverse concave-channel 150 is, approximately U-shaped. However, for convenience of manufacture, such as mold unloading, said side walls 143 may not be parallel to the longitudinal axis 158; that is, the section of said normal concave-channel 140 or the reverse concave-channel 150 is, approximately trapezoidal, even approximately triangle.
Taking the longitudinal axis 158 as a rotary axis, make a cylindrical surface with a radius R1 and intersects with said main rotary wall 138 to form an intersection, line, and create cutting plane M1 through said intersection line and perpendicular to the generating line of the main rotary wall 138 (with the axis 158 as rotary axis). Said cutting plane M1 divides the seal membrane 130 into an inner portion 156 (as in
As shown in
As
Referring to
Said side sealing-wall 143 has effects similar to reinforcing ribs those described in the background, all of the side walls 143 together reinforcing the axial tensile stiffness in the lip-adjacent area; and said side walls 143 increase the axial tensile stiffness without increasing the, hoop stiffness, thus increasing the axial stiffness without increasing the hoop force, such that which can effectively reduce the stick-slip described in the background. In this embodiment, 16 side walls 143 are included, while more or less side walls also can increase the axial tensile stiffness.
In summary, the structure of concave-channels has the functions of enlarging hoop circumference, reducing the wrapped area, reducing the actual contact area of the two surfaces between the instrument and the seal membrane, improving lubrication reliability, increasing the axial tensile stiffness, etc., thereby, the frictional resistance and the stick-slip can be greatly reduced, and the probability of inversion is reduced and the comfort of application is improved.
Defining the axis of said sealing lip 134 as the longitudinal axis 158, and a transverse plane 159 that is generally perpendicular to the longitudinal axis 158. Said wall 135 including an inner sealing-wall 141, an outer sealing-wall 142 and a side sealing-wall 143. Said inner sealing-wall 141 extends laterally from the sealing lip 134 to the flange 136; said an outer sealing-wall 142 extends laterally from the sealing lip 134 to tilted-sealing-wall 144; while said tilted-sealing-wall 144 and said inner sealing-wall 141 (or the flange 136) are intersected. The first side of said side sealing-wall 143 intersects the inner sealing-wall 141 and form a line 145a, 145b; the second side of said side sealing-wall 143 intersects the outer sealing-wall 142 to form a line 146a, 146b; the third side of said side sealing-wall 143 intersects the tilted-sealing-wall 144 to form a line of intersection 147a, 147b, One end of said tilted-sealing-wall 144 intersects the outer sealing-wall 142 to form a line 148a. 148b; The other end of said tilted-sealing-wall 144 intersects the inner side wall 142 to form a line 149a, 149b.
In the lip-adjacent area, said 2 adjacent side sealing-wall 143 and the outer sealing-wall 142 therebetween form a concave-channel that is recessed from the proximal surface toward the distal surface and the opening oriented to the proximal surface, which is defined as the normal concave-channel 140; meanwhile, said 2 adjacent side sealing-wall 143 and the inner sealing-wall 141 there between form a concave-channel that is recessed from the distal surface toward the proximal surface and the opening oriented to the distal surface, which is defined as the reverse concave-channel 150. Said inner sealing-wall 141, said side sealing-wall 143 and said outer sealing-wall 142 forms a series of normal concave-channel and reverse concave-channel, and said normal concave-channel and reverse concave-channel alternately distributed around the sealing lip 134, extending laterally outward and gradually increasing in axial depth. In the lip-adjacent area, a series of concave-channels with the normal and reverse alternately and with the increasing axial depth form a seamless sealing wall 135.
In the lip-adjacent area, the side sealing-wall 143 is a surface defined by both sides and extending laterally outward from the sealing lip 134 and gradually widening; while outside the lip-adjacent area, said side sealing-wall 143 is a tapered region defined by the sides, said side sealing-wall 143 is approximately obtuse triangular near the boundary of the lip-adjacent area. That is, when said normal concave-channel 140 extending laterally outward, the depth of it gradually increases in the lip-adjacent area, while gradually decreases outside the lip-adjacent area. Moreover, the 2 adjacent side walls 143 and the inner sealing-wall 141 there between only a distinct reverse concave-channel is formed in the lip-adjacent area, while no distinct reverse concave-channel is formed outside the lip-adjacent area. From the perspective of the distal surface, said normal concave-channel 140 is represented by a hollow convex-rib that is raised on the distal surface. Said rib extends laterally outward from the sealing lip and gradually increase in height, and abrupt change occurs near the boundary of the lip-adjacent area, and the height thereof rapidly decreases.
Optionally, the seal membrane 230 has a U-shaped solid-rib raised from the distal surface B of the outer sealing-wall 142. The U-shaped solid-rib is formed by two adjacent ribs 251 and a rib 252 there between. Although the sectional shape of the U-shaped ribs in the present embodiment approximates a U-shape, it may be approximately trapezoidal, other open polygons, circular rings or other closed polygons.
Those skilled in the art easily understand that the reasonable fillet transition can avoid stress concentration, or make certain areas defaulted more easily. Due to the small size of the seal membrane, especially the area near the sealing lip is smaller, with such, a small size and different chamfer, the shape of the seal membrane looks different. In order to clearly show the geometric relationship of the elements, the embodiment of the invention is generally the pattern without the fillet.
Many different embodiments and examples of the invention have been shown and described. One of those ordinary skilled in the art will be able to make adaptations to the methods and apparatus by appropriate modifications without departing from the scope of the invention. The structure and the fixing manner of the protector assembly disclosed in U.S. Pat. No. 7,788,861 are used in the example of the present invention. While the structure and the fixing manner of the protector assembly disclosed in U.S. Pat. Nos. 5,342,315, 7,988,671, or US20050131349A1 can be used; or simply modify the fixing manner of the protector; in some applications, the protector assembly may not be included. The approximate U-shaped concave-channels and the approximate V-shaped concave-channels described in this embodiment cannot be limited to U-shaped or V-shaped. It has been mentioned many times in the invention that the concave-channel extends laterally outward from the sealing lip, and the so-called “extending laterally outward” should not be limited to a straight line. Said “extending laterally outward” can be a spiral, a line segment, a multi-section arc line and so on. In the invention, the positional relationship of the intersecting surfaces composed <of said concave-channel and the intersection line thereof are described with reference to specific embodiments, and the methods of increasing curved surfaces to form a multifaceted mosaic or using of the high-order curved surface to make the intersection line and the concave-channel shape to look different from said embodiment. However, it can be considered not deviated from the scope of the invention, as long as it conforms to the general idea of the invention. Several modifications have been mentioned, to those skilled in the art, other modifications are also conceivable. Therefore, the scope of the invention should follow the additional claims, and at the same time, it should not be understood that it is limited by the specification of the structure, material or behavior illustrated and documented in the description and drawings.
Number | Date | Country | Kind |
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201610625809.2 | Aug 2016 | CN | national |
This application is a continuation of International Patent Application No. PCT/CN2017/093606 with a filing date of Jul. 20, 2017, designating the United States, now pending, and further claims priority to Chinese Patent Application No. 201610625809.2 with a filing date of Aug. 2, 2016. The content of the aforementioned applications, including any intervening amendments thereto, are incorporated herein by reference.
Number | Date | Country | |
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Parent | PCT/CN2017/093606 | Jul 2017 | US |
Child | 16243687 | US |