CN208660046U - Pull out needle pedestal in chemotherapy infusion port - Google Patents

Abstract

Needle pedestal is pulled out at chemotherapy infusion port, belongs to chemotherapy of tumors field of medical device.Needle stand is pulled out containing fixed ring and fixed cover, fixed cover symmetrically sets the first and second semicircular ring, and the first and second semicircle interannular has ring cavity.First semicircular ring contains the first and second end, and first end sets the first curved channel.Second semicircular ring contains third and fourth end, and third end sets the second curved channel.First and third end is hinged.It is fixed to cover at the top of fixed ring, if the pin hole of the lock chamber of the ring cavity of connection and connection lock chamber.Fixed cover contains mutually matched first and second semicircle cover, and the first semicircle cover is connect with the first semicircular ring, and the second semicircle cover is connect with the second semicircular ring.Its is easy to operate, it is convenient to pull out needle, needle is avoided to stab.First and second curved channel tilts down extension, convenient for holding.It is set at the top of first semicircle cover close to the second semicircle cover side as the first convex block of arcwall face.It is set at the top of second semicircle cover close to the first semicircle cover side as the second convex block of arcwall face, the wing of needle is arched upward convenient for holding and pulling out needle.

Description

Pull out needle pedestal in chemotherapy infusion port

Technical field

The utility model relates to chemotherapy of tumors field of medical device, pull out needle bottom in particular to a kind of chemotherapy infusion port Seat.

Background technique

Chemotherapy is the abbreviation of chemotherapy, is proliferation, the infiltration, transfer that cancer cell is prevented using chemicals, directly To a kind of final therapeutic modality for killing cancer cell.Since Cancer Patients during Chemotherapy usually needs frequent, a large amount of infusions, cause Blood vessel elasticity is deteriorated；And the vascular toxicity of part chemotherapeutics is big, easily causes phlebitis, and conventional peripheral intravenous injection is tired It is difficult.

In the prior art, the infusion of chemotherapy of tumors is usually carried out using transfusion port.Because transfusion port weekly needle exchange when to make With special needle bent, when nurse pulls out needle, resistance is larger when puncturing seat due to extracting, and nurse is after firmly extracting due to inertia Effect hold needle hand can automatic rebound go back to stab to easily causing needle, have every year in one department of Research statistics Event is pierced in several startings, is damaged to the health of healthcare givers.

Utility model content

Needle pedestal is pulled out the purpose of this utility model is to provide a kind of chemotherapy infusion port, it is easy to operate, to pull out needle convenient, and Can be avoided medical staff, there is a situation where needles to stab when pull out needle operation.

A kind of chemotherapy infusion port pull out needle pedestal comprising: fixed ring and fixed cover, fixed cover include symmetrically arranged first Semicircular ring and the second semicircular ring, have a ring cavity between the first semicircular ring and the second semicircular ring, the first semicircular ring includes opposite the One end and the second end, first end offer the first curved channel, and the second semicircular ring includes opposite third end and Four ends, third end offer the second curved channel, and first end and third end are hinged, and fixed be provide with is placed in fixed ring top Portion, the fixed pin hole for being covered with the lock chamber being connected to ring cavity and being connected to lock chamber, fixed cover include mutually matched first Semicircle cover and the second semicircle cover, pin hole are set between the first semicircle cover and the second semicircle cover, the first semicircle cover and the first semicircle Ring connection, the second semicircle cover are connect with the second semicircular ring.

Further, in the utility model preferred embodiment, the distance of the first curved channel to fixed ring bottom from First end is gradually reduced to the second end, and the distance of the second curved channel to fixed ring bottom is from third end to the 4th end It is gradually reduced.

Further, in the utility model preferred embodiment, the distance of the top-to-bottom of the first semicircular ring is from One end is gradually reduced to the second end, the distance of the top-to-bottom of the second semicircular ring from third end to the 4th end gradually Reduce.

Further, in the utility model preferred embodiment, one end of the separate first end of the first curved channel Equipped with the first opening being connected to ring cavity, one end of the separate third end of the second curved channel is equipped be connected to ring cavity second Opening.

Further, in the utility model preferred embodiment, the first curved channel runs through the second end, the second arc The 4th end, one end of the separate first end of the first curved channel and the separate third end of the second curved channel are run through in channel One end connection.

Further, in the utility model preferred embodiment, the first convex block is provided at the top of the first semicircle cover, the The side close to the second semicircle cover of one convex block is arcwall face, is provided with the second convex block, the second convex block at the top of the second semicircle cover Close to the first semicircle cover side be arcwall face.

Further, in the utility model preferred embodiment, the side far from the second semicircle cover of the first convex block is Arcwall face, the side far from the first semicircle cover of the second convex block are arcwall face.

Further, in the utility model preferred embodiment, the side close to the second semicircular ring of the second end is set It is equipped with the first arc strip, the side close to the first semicircular ring of the 4th end is provided with the first arc with the cooperation of the first arc strip Slot.

Further, in the utility model preferred embodiment, the side close to the second semicircle cover of the first semicircle cover It is provided with the second arc strip, the side close to the first semicircle cover of the second semicircle cover is provided with second with the cooperation of the second arc strip Arc groove.

A kind of chemotherapy infusion port pull out needle pedestal comprising: fixed ring and fixed cover, fixed cover include symmetrically arranged first Semicircular ring and the second semicircular ring, have a ring cavity between the first semicircular ring and the second semicircular ring, the first semicircular ring includes opposite the One end and the second end, first end offer the first curved channel, the distance of the first curved channel to fixed ring bottom from First end is gradually reduced to the second end, and the second semicircular ring includes opposite third end and the 4th end, and third end is opened Equipped with the second curved channel, the distance of the second curved channel to fixed ring bottom is gradually reduced from third end to the 4th end, First end and third end are hinged, and fixed be provide with being placed at the top of fixed ring, it is fixed be covered with the lock chamber being connected to ring cavity and The pin hole being connected to lock chamber, fixed cover include that mutually matched first semicircle cover and the second semicircle cover, pin hole are set to first Between semicircle cover and the second semicircle cover, the first semicircle cover is connect with the first semicircular ring, is provided with first at the top of the first semicircle cover The side close to the second semicircle cover of convex block, the first convex block is arcwall face, and the second semicircle cover connect with the second semicircular ring, the second half The second convex block is provided at the top of dome, the side close to the first semicircle cover of the second convex block is arcwall face.

The beneficial effect of the utility model embodiment is:

Needle pedestal is pulled out at chemotherapy infusion port provided by the utility model, the first curved channel of first end and the second end Second curved channel is respectively used to be arranged thumb and index finger.With thumb and index finger respectively to the first semicircular ring and the second semicircle Ring directly controls, and maintains good operating flexibility, convenient for the first semicircular ring and the accurate adjusting of the second semicircular ring, force Convenient, fixing-stable is conveniently；Thumb and index finger cover for fixed operation are set in curved channel, to finger when avoiding springing back It stabs.The third end of the first end of first semicircular ring and the second semicircular ring is hinged, convenient for finger-stall is set to curved channel Transfusion port is fixed after finding suitable angle after interior each conduit convenient for avoiding being connected to transfusion port upper end.

The setting that first curved channel and the second curved channel are extended to the bottom of fixed ring, protrudes into arc convenient for finger With certain angle tilted down when shape channel, makes palm that there is certain space to sufferer skin surface, provide it The placement operation space of remaining finger and elbow operates more smooth.

It is provided with the first convex block at the top of first semicircle cover, the second convex block is provided at the top of the second semicircle cover, first is convex The side of the close pin hole of block and the second convex block is arcwall face, is gradually being cooperated convenient for the first semicircle cover and the second semicircle cover The wing of wing needle is gradually arched upward in the process, convenient for the gripping of operator's wing needle wing over the ground, pulls out needle more convenient operation.

Detailed description of the invention

It, below will be to use required in embodiment in order to illustrate more clearly of the technical solution of the utility model embodiment Attached drawing be briefly described, it should be understood that the following drawings illustrates only some embodiments of the utility model, therefore should not be by Regard the restriction to range as, for those of ordinary skill in the art, without creative efforts, may be used also To obtain other relevant attached drawings according to these attached drawings.

Fig. 1 is that needle pedestal is pulled out in the structural schematic diagram at the first visual angle in chemotherapy infusion port provided by the embodiment of the utility model；

Fig. 2 is that needle pedestal is pulled out in the structural schematic diagram at the second visual angle in chemotherapy infusion port provided by the embodiment of the utility model；

Fig. 3 is that needle pedestal is pulled out in first working condition at third visual angle in chemotherapy infusion port provided by the embodiment of the utility model Structural schematic diagram；

Fig. 4 is that needle pedestal is pulled out in second working condition at third visual angle in chemotherapy infusion port provided by the embodiment of the utility model Structural schematic diagram；

Fig. 5 is the cross-sectional view that needle pedestal is pulled out at chemotherapy infusion port provided by the embodiment of the utility model.

Icon: needle pedestal is pulled out in 10- chemotherapy infusion port；100- fixed ring；The first semicircular ring of 110-；111- first end； The first curved channel of 1111-；1112- first is open；112- the second end；The first arc strip of 1121-；The second semicircular ring of 120-； 121- third end；The second curved channel of 1211-；1212- second is open；The 4th end 122-；The first arc groove of 1221-； The fixed cover of 200-；210- lock chamber；220- pin hole；The first semicircle cover of 230-；The first convex block of 231-；The second arc strip of 232-； The second semicircle cover of 240-；The second convex block of 241-；The second arc groove of 242-.

Specific embodiment

It is practical new below in conjunction with this to keep the objectives, technical solutions, and advantages of the embodiments of the present invention clearer Attached drawing in type embodiment, the technical scheme in the utility model embodiment is clearly and completely described, it is clear that is retouched The embodiment stated is the utility model a part of the embodiment, instead of all the embodiments.Usually here in attached drawing description and The component of the utility model embodiment shown can be arranged and be designed with a variety of different configurations.

Therefore, requirement is not intended to limit to the detailed description of the embodiments of the present invention provided in the accompanying drawings below The scope of the utility model of protection, but it is merely representative of the selected embodiment of the utility model.Based in the utility model Embodiment, every other embodiment obtained by those of ordinary skill in the art without making creative efforts, all Belong to the range of the utility model protection.

It should also be noted that similar label and letter indicate similar terms in following attached drawing, therefore, once a certain Xiang Yi It is defined in a attached drawing, does not then need that it is further defined and explained in subsequent attached drawing.

In the description of the present invention, it should be noted that term " first ", " second " " third ", " the 4th " etc. only It is described for distinguishing, is not understood to indicate or imply relative importance.

The orientation or positional relationship of the instructions such as term " on ", "lower", "inner", "outside", " top ", " bottom ", " opposite " is Be based on the orientation or positional relationship shown in the drawings or the utility model product using when the orientation usually put or position close System, is merely for convenience of describing the present invention and simplifying the description, rather than the device or element of indication or suggestion meaning are necessary It with specific orientation, is constructed and operated in a specific orientation, therefore should not be understood as limiting the present invention.

In addition, the terms such as " vertical " are not offered as requiring absolute upright between component, but can be slightly tilted.As " hung down Directly " only refer to that its direction is in contrast more vertical, be not indicate the structure have to it is completely vertical, but can be slightly Inclination.

In the description of the present invention, it should also be noted that, unless otherwise clearly defined and limited, term " is set Set ", " installation ", " connected ", " connection " etc. shall be understood in a broad sense.For example, it may be being fixedly connected, it is also possible to detachably connect It connects, or is integrally connected；It can be mechanical connection, be also possible to be electrically connected；It can be directly connected, intermediate matchmaker can also be passed through Jie is indirectly connected, and can be the connection inside two elements.It for the ordinary skill in the art, can be with concrete condition Understand the concrete meaning of above-mentioned term in the present invention.

Embodiment

Also referring to Fig. 1 and Fig. 2, the present embodiment proposes that needle pedestal 10, including fixed ring 100 are pulled out in a kind of chemotherapy infusion port With fixed cover 200, fixed cover 200 is set to 100 top of fixed ring and is connected to the inside of fixed cover 200.

Also referring to Fig. 3, Fig. 4 and Fig. 5, fixed cover 200 includes symmetrically arranged first semicircular ring 110 and the second semicircle Ring 120.First semicircular ring 110 is protruded to the side far from the second semicircular ring 120, and the second semicircular ring 120 is to far from the first semicircle The side of ring 110 is protruded, and has ring cavity between the first semicircular ring 110 and the second semicircular ring 120.

First semicircular ring 110 includes opposite first end 111 and the second end 112, and first end 111 offers first Curved channel 1111, the first curved channel 1111 along the first semicircular ring 110 circumference from first end 111 to the second end 112, First curved channel 1111 is directed away from the side protrusion of the second semicircular ring 120.

Second semicircular ring 120 includes opposite third end 121 and the 4th end 122, and third end 121 offers second Curved channel 1211, the second curved channel 1211 along the second semicircular ring 120 circumference from third end 121 to the 4th end 122, Second curved channel 1211 is directed away from the side protrusion of the first semicircular ring 110.

First end 111 and third end 121 are hinged.In the present embodiment, close second semicircular ring of first end 111 The axial direction of a 120 lateral edge fixed ring 100 is provided with multiple first axle sleeves, close first semicircular ring 110 of third end 121 The axial direction of one lateral edge fixed ring 100 is provided with multiple second axle sleeves, multiple first axle sleeves and the alternate setting of multiple second axle sleeves, more Rotation setting shaft in a first axle sleeve and multiple second axle sleeves, to enable first end 111 and third end 121 to turn Axis is that rotary shaft mutually rotates, to keep the second end 112 and the 4th end 122 close to each other or be located remotely from each other.

Above-mentioned setting, the first curved channel 1111 and the second curved channel 1211 are respectively used to be arranged thumb and index finger. The first semicircular ring 110 and the second semicircular ring 120 are directly controlled respectively using thumb and index finger, maintain good operation spirit Activity, it is convenient convenient for the accurate adjusting to the first semicircular ring 110 and the second semicircular ring 120, force convenience, fixing-stable；For The thumb and index finger cover of fixed operation are set in curved channel, avoid stabbing finger when rebound.First end 111 and third End 121 it is hinged convenient for finger-stall is set in curved channel operation, convenient for avoiding being connected to respectively leading for transfusion port upper end Transfusion port is fixed after finding suitable angle after pipe.

In this embodiment, the first curved channel 1111 is to the distance of 100 bottom of fixed ring from first end 111 to second end Portion 112 is gradually reduced, and the distance of the second curved channel 1211 to 100 bottom of fixed ring is from third end 121 to the 4th end 122 It is gradually reduced.

Above-mentioned the first curved channel 1111 and the second curved channel 1211 is set to what the bottom of fixed ring 100 was extended It sets, with certain angle tilted down when protruding into curved channel convenient for finger, palm is made to have one to sufferer skin surface Fixed space provides the placement operation space of remaining finger and elbow etc., operates more smooth.

The distance of the top-to-bottom of first semicircular ring 110 is gradually reduced from first end 111 to the second end 112, the The distance of the top-to-bottom of two semicircular rings 120 is gradually reduced from third end 121 to the 4th end 122.The thickness of fixed ring 100 The extending direction for spending arcuately channel is gradually reduced, and is adapted to the curved channel being obliquely installed, the first curved channel of being more convenient for 1111 and second curved channel 1211 setting.

In the present embodiment, one end of the separate first end 111 of the first curved channel 1111 is equipped with the be connected to ring cavity One opening 1112, one end of the separate third end 121 of the second curved channel 1211 are equipped with the second opening being connected to ring cavity 1212。

Fixed ring 100 is protruded into the end of the finger of first opening 1112 and the second opening 1212 convenient for protruding into curved channel Inside, directly contacted convenient for finger end with patient's skin surface, convenient for improve fixed ring 100 transfusion port is positioned it is accurate Property, convenience keep the fixation to transfusion port more stable convenient for pressing transfusion port.

First curved channel 1111 run through the second end 112, the second curved channel 1211 run through the 4th end 122, first One end of one end of the separate first end 111 of curved channel 1111 and the separate third end 121 of the second curved channel 1211 Connection.

Two fingers protruded into curved channel can offset, it is more stable to the control of fixed ring 100 and meanwhile convenient for difference The operator of finger length uses.

Further, the side close to the second semicircular ring 120 of the second end 112 is provided with the first arc strip 1121, the The side close to the first semicircular ring 110 of four ends 122 is provided with the first arc groove 1221 with the cooperation of the first arc strip 1121.

When the second end 112 and the 4th end 122 cooperate, 1221 phase interworking of the first arc strip 1121 and the first arc groove It closes, can be improved the stability of the second end 112 and the connection of the 4th end 122, to improve the stabilization that fixed ring 100 uses Property.

Fixed cover 200 is set to 100 top of fixed ring, and the inside of fixed cover 200 is equipped with the lock chamber being connected to ring cavity 210, lock chamber 210 is adapted to the shape of the transfusion seat of transfusion port, size, and fixed cover 200 is covered at transfusion port after positioning Transfusion port is stably fixed in lock chamber 210, transfusion port is effectively prevent to slip by transfusion seat, convenient for pulling out needle operation.Fixed cover The pin hole 220 being connected to lock chamber 210 is offered in the middle part of 200 top.

Fixed cover 200 includes that mutually matched first semicircle cover 230 and the second semicircle cover 240, pin hole 220 are set to first Between semicircle cover 230 and the second semicircle cover 240, the first semicircle cover 230 is connect with the first semicircular ring 110, the second semicircle cover 240 with The connection of second semicircular ring 120.First semicircle cover 230 and the second semicircle cover 240 are in the first semicircular ring 110 and the second semicircular ring 120 Relative motion in realize opening and closing.

When pulling out needle pedestal 10 using chemotherapy infusion port and pull out needle operation, control the second end 112 and the 4th end first 122 are located remotely from each other, and the first semicircle cover 230 and the second semicircle cover 240 are located remotely from each other at this time, as shown in Figure 4.Finger controls fixed ring 100 movements keep fixed cover 200 corresponding with transfusion port position, and the wing needle for being connected to transfusion port is corresponding with the position of pin hole 220, Transfusion port is fixed in lock chamber 210 by the opening between closure the second end 112 and the 4th end 122, as shown in Figure 3.

The side close to the second semicircle cover 240 of first semicircle cover 230 is provided with the second arc strip 232, the second semicircle cover 240 side close to the first semicircle cover 230 is provided with the second arc groove 242 with the cooperation of the second arc strip 232, makes second end When portion 112 and the 4th end 122 cooperate, the connection of the first semicircle cover 230 and the second semicircle cover 240 is more stable.

In the present embodiment, the top of the first semicircle cover 230 is provided with the first convex block 231, the first convex block 231 close to the The side of two semicircle covers 240 is arcwall face, and the top of the second semicircle cover 240 is provided with the second convex block 241, the second convex block 241 It is arcwall face close to the side of the first semicircle cover 230.The arcwall face is protruded to the direction far from fixed ring 100, makes arcwall face Thickness be gradually increased from the end close to pin hole 220 to far from the end of pin hole 220.

Above-mentioned set-up mode, convenient for the first semicircle cover 230 and the second semicircle cover 240 by butterfly during gradually cooperating The wing of wing needle gradually arches upward, and convenient for the gripping of operator's wing needle wing over the ground, pulls out needle more convenient operation.

Further, the first convex block 231 far from the second semicircle cover 240 side be arcwall face, the second convex block 241 it is remote Side from the first semicircle cover 230 is arcwall face.The arcwall face is protruded to the direction far from fixed ring 100, makes arcwall face Thickness is gradually reduced from the end close to pin hole 220 to the end far from pin hole 220, convenient for finger to the tail of the wing of wing needle The gripping at end.

To sum up, needle pedestal 10, the first semicircular ring 110 and the second semicircular ring are pulled out in chemotherapy infusion port provided by the utility model The setting of 120 handover, is arranged convenient for finger, transfusion port is fixed convenient for avoiding being connected to each conduit of transfusion port upper end. The setting thumb and index finger of curved channel directly control fixed ring 100, and flexible operation, accurate adjusting, force are convenient, solid It is fixed to stablize convenient and avoid stabbing finger when rebound.First curved channel 1111 and the second curved channel 1211 are to fixed ring The setting that 100 bottom is extended makes palm have certain space to sufferer skin surface, provides remaining finger and hand The placement operation space of elbow operates more smooth.The side of the close pin hole 220 of first convex block 231 and the second convex block 241 is arc Face, convenient for the wing of wing needle gradually arches upward, needle more convenient operation is pulled out in gripping.

The above descriptions are merely preferred embodiments of the present invention, is not intended to limit the utility model, for this For the technical staff in field, various modifications and changes may be made to the present invention.It is all in the spirit and principles of the utility model Within, any modification, equivalent replacement, improvement and so on should be included within the scope of protection of this utility model.

Claims (10)

1. needle pedestal is pulled out at a kind of chemotherapy infusion port, which is characterized in that including fixed ring and fixed cover, the fixed cover includes symmetrical The first semicircular ring and the second semicircular ring being arranged have ring cavity between first semicircular ring and second semicircular ring, described First semicircular ring includes opposite first end and the second end, and the first end offers the first curved channel, and described Two semicircular rings include opposite third end and the 4th end, and the third end offers the second curved channel, and described first End and the third end are hinged, and the fixation, which is provide with, to be placed at the top of the fixed ring, and the fixation is covered with and the ring The lock chamber of chamber connection and the pin hole that be connected to the lock chamber, the fixed cover include mutually matched first semicircle cover and the Two semicircle covers, the pin hole are set between first semicircle cover and second semicircle cover, first semicircle cover and institute The connection of the first semicircular ring is stated, second semicircle cover is connect with second semicircular ring.

2. needle pedestal is pulled out at chemotherapy infusion port according to claim 1, which is characterized in that first curved channel is described in The distance of fixed ring bottom is gradually reduced from the first end to the second end, and second curved channel is to described solid The distance for determining ring bottom is gradually reduced from the third end to the 4th end.

3. needle pedestal is pulled out at chemotherapy infusion port according to claim 2, which is characterized in that the top of first semicircular ring is arrived The distance of bottom is gradually reduced from the first end to the second end, the top-to-bottom of second semicircular ring away from It is gradually reduced from from the third end to the 4th end.

4. needle pedestal is pulled out at chemotherapy infusion port according to claim 1, which is characterized in that first curved channel it is separate One end of the first end is equipped with the first opening being connected to the ring cavity, the separate third of second curved channel One end of end is equipped with the second opening being connected to the ring cavity.

5. needle pedestal is pulled out at chemotherapy infusion port according to claim 4, which is characterized in that first curved channel runs through institute The second end is stated, second curved channel runs through the 4th end, the separate first end of first curved channel The one end in portion is connected to one end far from the third end of second curved channel.

6. needle pedestal is pulled out at chemotherapy infusion port according to claim 1, which is characterized in that set at the top of first semicircle cover It is equipped with the first convex block, the side close to second semicircle cover of first convex block is arcwall face, second semicircle cover Top is provided with the second convex block, and the side close to first semicircle cover of second convex block is arcwall face.

7. needle pedestal is pulled out at chemotherapy infusion port according to claim 6, which is characterized in that first convex block far from described The side of second semicircle cover is arcwall face, and the side far from first semicircle cover of second convex block is arcwall face.

8. needle pedestal is pulled out at chemotherapy infusion port according to claim 1, which is characterized in that the second end close to described The side of second semicircular ring is provided with the first arc strip, and the side close to first semicircular ring of the 4th end is provided with With the first arc groove of first arc strip cooperation.

9. needle pedestal is pulled out at chemotherapy infusion port according to claim 1, which is characterized in that the close institute of first semicircle cover The side for stating the second semicircle cover is provided with the second arc strip, and the side close to first semicircle cover of second semicircle cover is set It is equipped with the second arc groove with second arc strip cooperation.

10. needle pedestal is pulled out at a kind of chemotherapy infusion port, which is characterized in that including fixed ring and fixed cover, the fixed cover includes pair The first semicircular ring and the second semicircular ring for claiming setting have ring cavity, institute between first semicircular ring and second semicircular ring Stating the first semicircular ring includes opposite first end and the second end, and the first end offers the first curved channel, described The distance of first curved channel to the fixed ring bottom is gradually reduced from the first end to the second end, and described Two semicircular rings include opposite third end and the 4th end, and the third end offers the second curved channel, and described second The distance of curved channel to the fixed ring bottom is gradually reduced from the third end to the 4th end, the first end Portion and the third end are hinged, and the fixation, which is provide with, to be placed at the top of the fixed ring, and the fixation is covered with and the ring cavity The lock chamber of connection and the pin hole being connected to the lock chamber, the fixed cover includes mutually matched first semicircle cover and second Semicircle cover, the pin hole are set between first semicircle cover and second semicircle cover, first semicircle cover with it is described The connection of first semicircular ring, is provided with the first convex block at the top of first semicircle cover, first convex block close to described second The side of semicircle cover is arcwall face, and second semicircle cover is connect with second semicircular ring, the top of second semicircle cover It is provided with the second convex block, the side close to first semicircle cover of second convex block is arcwall face.