CN115808613A - Chip heat dissipation test seat with heat measurement function - Google Patents

Abstract

The invention discloses a chip heat dissipation test seat with a heat measurement function, which relates to the technical field of chip testing, wherein the coverage area of a sensor is relatively large, the space in which an air duct can be formed is smaller, the heat dissipation effect of the test seat on a chip after testing is relatively poorer, if more air ducts are formed in the test seat, the heat dissipation on the chip is fast due to high air circulation speed, the temperature collection of the chip has certain deviation, and certain deviation exists in high-temperature strength test data.

Description

Chip heat dissipation test seat with heat measurement function

Technical Field

The invention relates to the technical field of chip testing, in particular to a chip heat dissipation test socket with a heat measurement function.

Background

The chip test seat is also called IC socket, IC test seat and IC socket; the chip testing seat mainly plays a role in connection and conduction; are commonly used for integrated circuit application functional verification. By some definition it is simply a connector that meets some test requirement of some chip. The static connector is a static connector between the PCB and the IC, can make the replacement and test of the chip more convenient, and does not need to repeatedly weld and take down the chip all the time, thereby reducing the damage of the IC and the PCB and achieving the effect of quick and efficient test.

To this end, the chinese application patent No.: CN113740699A discloses a test socket and a control method thereof, a test apparatus and a storage medium, the test socket includes a base, a cover and a temperature control component, wherein the base is provided with a test component and an elastic needle, the cover is connected to the base and can rotate relative to the base to form a covering state or a separating state, one side of the cover facing the base is provided with a press block for pressing a to-be-tested piece placed on the base when the base and the cover are in the covering state, so that the to-be-tested piece is in contact with the test component, the temperature control component is disposed between the cover and the press block for conducting heat conduction through the press block, carrying out temperature detection and temperature control on the to-be-tested piece, and when the base and the cover are in the covering state, contacting the elastic needle to connect an external circuit board through the elastic needle. Through the mode, the temperature of the chip can be adjusted and collected when the chip is tested, and the temperature condition of the chip test is accurately controlled.

To this end, chinese application patent No.: CN115389037A discloses a temperature measuring device, which comprises a suction cup and a metal heat conducting strip, wherein the suction cup has an outer surface and an inner surface which are opposite to each other, and comprises a first opening arranged on the inner surface and a first cavity communicated with the first opening, the first cavity is located between the outer surface and the inner surface, the metal heat conducting strip is arranged in the first cavity, and extends from a first end of the first opening to a second end of the first opening along a first direction.

To this end, the chinese application patent No.: CN108507705A discloses a chip temperature measuring device, which includes a test socket, a temperature measuring device installed in the test socket, at least one first conduction piece and at least one second conduction piece, wherein the temperature measuring device is used for contacting with the lower surface of a chip to be tested, the first conduction piece is used for conducting the temperature measuring device with an external test circuit, and the second conduction piece is used for conducting the chip to be tested with the external test circuit. The temperature measuring device provided by the invention can be used for measuring the temperature of the lower surface of the chip, so that the measured temperature is closer to the actual temperature of the chip, the measurement error is reduced, and the accuracy of the measurement result is improved.

Now when carrying out intensity test to the chip at the chip seat, the high temperature behavior of chip also need measure, the temperature of chip is through carrying out real-time monitoring from the sensor, in order to improve real-time supervision's accurate nature, the sensor cover face will be great relatively, inside can form the space in wind channel just also littleer, test the seat and carry out radiating effect just also relatively to the chip after the test, like inside more wind channel that forms, the heat that the circulation of air is fast on the chip gives off fast, chip temperature gathers and has certain deviation, just also there is certain deviation in high temperature intensity test data.

In order to solve the above problems, a chip heat dissipation test socket with a heat measurement function is provided.

Disclosure of Invention

The invention aims to provide a chip heat dissipation test socket with a heat measurement function, which solves the problem of mutual interference between temperature acquisition and heat dissipation of a chip socket in the prior art.

In order to achieve the purpose, the invention provides the following technical scheme: a chip heat dissipation test seat with a heat measuring function comprises an upper sealing cover, wherein the bottom end of the upper sealing cover is connected with a test base, the upper end of the test base is connected with a lifting rod, the upper end of the test base is connected with a fixed block, the bottom end of the test base is connected with a heat dissipation waistcoat, one side of the test base is fixedly connected with a first heat dissipation fan, the upper end of the heat dissipation waistcoat is provided with heat dissipation fins, and the bottom end of the heat dissipation waistcoat is provided with a second heat dissipation fan;

the temperature measurement device comprises a test base, a temperature measurement frame, a heat conduction wrapping sheet, a temperature measurement sensor and a heat conduction sheet, wherein the test base is embedded and connected with a test seat, a chip clamping plate is installed at the upper end of the test seat, a reserved groove is formed in the inner side of the chip clamping plate, the upper end of the chip clamping plate is connected with the temperature measurement frame, the upper end of the temperature measurement frame is connected with the heat conduction wrapping sheet, the temperature measurement sensor is embedded in the heat conduction wrapping sheet, and the top end of the heat conduction wrapping sheet is fixedly connected with the heat conduction sheet;

the inside embedding of test base is connected with the division board, the logical groove of dispelling the heat has been seted up to the upper end of division board, fixedly connected with location slide rail on the inner wall of test base, the inside embedding of location slide rail is connected with spacing slider, spacing slider's the sealed chock plate of one end fixedly connected with, the bottom of sealed chock plate is connected with plays and holds in the palm the strip, the bottom that plays to hold in the palm the strip sets up and is connected with hydraulic push rod.

Preferably, the upper sealing cover is connected with the test base through a lifting rod, the lifting rod penetrates through the inside of a fixing block at the upper end of the upper sealing cover, the fixing block is connected with the lifting rod in a sliding mode, and sealing gaskets are fixedly connected to the inner wall of the upper sealing cover and the top surface of the test base.

Preferably, the bottom of test base is provided with a set of through-hole, the inside of test base and heat dissipation vest is linked together, the heat dissipation vest is made for the copper-nickel alloy.

Preferably, the both sides fixedly connected with of detecting the seat links up the strip, be connected with the link on the top surface of detecting the seat, the inside embedding of chip splint is connected with a set of axostylus axostyle, and the axostylus axostyle embedding is in the inside of link, swing joint between link and the chip splint, install the PIN needle on the inner wall of detecting the seat.

Preferably, the upper end at the chip splint is installed to the even equidistance of temperature measurement frame, the inside embedding in a set of logical groove in chip splint upper end has a set of temperature measurement frame, the temperature measurement frame is frame construction, the temperature measurement frame is made for the copper metal.

Preferably, the two ends of the inner wall of the temperature measuring sensor are attached to the inner part of the heat conduction wrapping sheet, and the top end of the heat conduction sheet is also closely attached to the inner wall of the temperature measuring frame.

Preferably, the sealing plug plate is provided with two sets of altogether, and is two sets of the sealing plug plate keeps same height, and is two sets of the sealing plug plate is respectively through the inside of limiting slide block embedding at two sets of location slide rails, the sealing plug plate is made for the silica gel material, protruding strip and the logical looks adaptation of heat dissipation groove that the sealing plug plate set up, the sealing plug plate sets up the position of protruding strip and has all wrapped up the rubber pad.

Preferably, the positioning slide rails are arranged in a curved shape, and the two groups of positioning slide rails on the same side have completely opposite bending directions.

Preferably, the two sides of the sealing plug plate are fixedly connected with limiting sliding blocks, the limiting sliding blocks are embedded in the positioning sliding rails, and the limiting sliding blocks are connected with the positioning sliding rails in a sliding mode.

Preferably, the top end of the heat dissipation waistcoat is fixedly connected with a hydraulic push rod, the output end of the hydraulic push rod is fixedly connected with the bottom end of the lifting and supporting strip, the longitudinal section of the lifting and supporting strip is L-shaped, and the lifting and supporting strip is connected with the sealing plug plate in a sliding mode.

Compared with the prior art, the invention has the following beneficial effects:

1. when the chip heat dissipation test seat with the heat measurement function works, firstly, when heat is collected in real time, a closed space is formed inside, the heat dissipation of the space is small, and the heat is transmitted in a heat radiation mode, meanwhile, the heat can be conducted to the upper end of the sensor through medium heat, the heat collection adopts multi-point-position common temperature measurement, the temperature measurement precision is improved, in addition, in the aspect of heat dissipation, the temperature measurement and the heat dissipation are distinguished in a middle isolation mode, the temperature measurement and the heat dissipation are mutually complemented, an internal air channel is smooth in heat dissipation, and the heat dissipation effect is excellent.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic view of an expanded structure of the upper cover and the test base of the present invention;

FIG. 3 is a schematic structural diagram of an upper cover and a first heat dissipation fan according to the present invention;

FIG. 4 is a schematic structural view of a temperature measuring rack and a chip clamp plate according to the present invention;

FIG. 5 is a schematic structural view of a heat dissipating fin and a second heat dissipating fan according to the present invention;

FIG. 6 is a schematic view of the structure of the temperature measuring rack and the connecting rack of the present invention;

FIG. 7 is a schematic structural view of the chip clamp plate according to the present invention in an unfolded state;

FIG. 8 is a schematic structural view of the partition plate and the heat dissipating through grooves of the present invention;

FIG. 9 is a schematic structural view of a temperature sensor and a heat-conducting fin according to the present invention;

FIG. 10 is a schematic view of the structure of the heat sink channel and the spacer of the present invention;

FIG. 11 is a schematic structural view of a positioning slide rail and a limiting slide block of the present invention;

FIG. 12 is a schematic structural view of a limiting slide block and a hydraulic push rod according to the present invention.

In the figure: 1. an upper sealing cover; 2. a test base; 3. a fixed block; 4. a heat dissipation vest; 5. adjusting a lifting rod; 6. a first heat dissipation fan; 7. a heat dissipating fin; 8. a second heat dissipation fan; 9. a chip clamp plate; 10. a temperature measuring frame; 11. a connecting frame; 12. a detection seat; 13. a connecting strip; 14. a thermally conductive wrapping sheet; 15. reserving a groove; 16. a PIN needle; 17. a separator plate; 18. a heat dissipation through groove; 19. a temperature sensor; 20. a heat conductive sheet; 21. a sealing plug plate; 22. positioning the slide rail; 23. a limiting slide block; 24. a hydraulic push rod; 25. and (4) lifting the supporting strip.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.

For a further understanding of the invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings.

With reference to fig. 1-12, the chip heat dissipation test socket with heat measurement function of the present invention comprises an upper sealing cover 1, a test base 2 is connected to the bottom end of the upper sealing cover 1, a lifting rod 5 is connected to the upper end of the test base 2, a fixing block 3 is connected to the upper end of the test base 2, the upper sealing cover 1 and the test base 2 are connected through the lifting rod 5, the lifting rod 5 penetrates through the inside of the fixing block 3 at the upper end of the upper sealing cover 1, the fixing block 3 and the lifting rod 5 are connected in a sliding manner, sealing gaskets are fixedly connected to the inner wall of the upper sealing cover 1 and the top surface of the test base 2, the upper sealing cover 1 and the test base 2 are more sealed by the engagement of the sealing gaskets, so that the hot air inside is not easily dissipated under the condition of ensuring sealing, the temperature measuring device arranged in the test base 2 can better measure the temperature in the test base, the measurement precision is remarkably improved, the bottom end of the test base 2 is connected with a heat dissipation waistcoat 4, a group of through holes are formed in the bottom end of the test base 2, the test base 2 is communicated with the inside of the heat dissipation waistcoat 4, the heat dissipation waistcoat 4 is made of copper-nickel alloy, when internal high-temperature gas is dissipated at the later stage, heat is transferred through a metal conductor, so that hot air flow and cold air flow can be exchanged, one side of the test base 2 is fixedly connected with a first heat dissipation fan 6, the upper end of the heat dissipation waistcoat 4 is provided with a heat dissipation fin 7, and the bottom end of the heat dissipation waistcoat 4 is provided with a second heat dissipation fan 8;

the inner part of the test base 2 is embedded and connected with a test base 12, a chip clamping plate 9 is installed at the upper end of the test base 12, a reserved groove 15 is formed in the inner side of the chip clamping plate 9, a temperature measuring frame 10 is connected at the upper end of the chip clamping plate 9, the temperature measuring frames 10 are evenly and equidistantly installed at the upper end of the chip clamping plate 9, a group of temperature measuring frames 10 are embedded in a group of through grooves in the upper end of the chip clamping plate 9, the temperature measuring frames 10 are arranged to be of a frame structure, the temperature measuring frames 10 are made of copper metal, the copper metal has good thermal conductivity, when a pressure test is carried out on a chip, the temperature can be transmitted to the upper end of the temperature measuring frames 10, the temperature is collected through the temperature measuring frames 10, the collected temperature is transmitted to the upper end of a temperature measuring sensor 19, the upper end of the temperature measuring frames 10 is connected with a heat conduction wrapping sheet 14, a temperature measuring sensor 19 is embedded in the heat conduction wrapping sheet 14, and a heat conduction sheet 20 is fixedly connected to the top end of the heat conduction wrapping sheet 14, two ends of the inner wall of a temperature measurement sensor 19 are attached to the inside of a heat conduction wrapping sheet 14, the top end of a heat conduction sheet 20 is also closely attached to the inner wall of a temperature measurement frame 10, connecting strips 13 are fixedly connected to two sides of a detection seat 12, a connecting frame 11 is connected to the top surface of the detection seat 12, a group of shaft rods are embedded and connected to the inside of a chip clamping plate 9 and embedded into the connecting frame 11, the connecting frame 11 is movably connected with the chip clamping plate 9, PIN needles 16 are installed on the inner wall of the detection seat 12, the temperature of the chip during pressure test rises and can be transmitted to the upper end of the temperature measurement frame 10, heat is transmitted to the upper end of the temperature measurement sensor 19 through the heat conduction sheet 20 until the heat is transmitted to the upper end of the temperature measurement sensor 19, and then is collected by the temperature measurement sensor 19, and mechanical bending motion is generated when the two metals are heated due to the difference of linear expansion coefficients of the two metals, calculate the temperature of locating the chip through crooked degree, the temperature through testing the chip further detects the heating capacity of chip, and the later stage of being convenient for carries out further perfection to the chip, and wherein temperature detect sensor 19 imbeds in the inside of heat-conduction parcel piece 14, and the contact surface is also abundanter, consequently also more sensitive to thermal response.

The inside of the test base 2 is embedded and connected with a partition board 17, the upper end of the partition board 17 is provided with a heat dissipation through groove 18, the inner wall of the test base 2 is fixedly connected with a positioning slide rail 22, the positioning slide rail 22 is arranged in a bent shape, the bending directions of two groups of positioning slide rails 22 on the same side are completely opposite, the positioning slide rail 22 in the bent state can better limit the motion track of a limiting slide block 23, the limiting slide block 23 can move regularly along the inside of the positioning slide rail 22, the limiting slide block 23 is embedded and connected inside the positioning slide rail 22, one end of the limiting slide block 23 is fixedly connected with a sealing plug board 21, the two sides of the sealing plug board 21 are fixedly connected with the limiting slide block 23, the limiting slide block 23 is embedded inside the positioning slide rail 22, the limiting slide block 23 is connected with the positioning slide rail 22 in a sliding manner, the sealing plug boards 21 are provided with two groups, the two groups of sealing plug boards 21 keep the same height, the two groups of sealing plug boards 21 are respectively embedded inside the two groups of positioning slide rails 22 through the limiting slide blocks 23, the sealing plug boards 21 are made of silica gel material, the sealing plug boards 21 are matched with the heat dissipation through the through grooves 18, the sealing plug boards 21, and rubber pads are arranged on the portions of the sealing plug boards,

two sets of sealed cock boards 21 are embedded into the inside that the logical groove 18 was led to in the heat dissipation, make the inside that the logical groove 18 was led to in the heat dissipation blocked up completely, the heat of upper end then can't transmit the lower extreme, in addition sealed cock board 21 has adopted the silica gel material to make, it is alternately to the heat transfer effect, the efficiency of heat transfer is reduced, therefore when the chip carries out pressure test, the temperature is not too much distribute and lead to the measuring result to appear the deviation, the bottom of sealed cock board 21 is connected with the support strip 25, the bottom that rises support strip 25 sets up and is connected with hydraulic rod 24, the fixedly connected with hydraulic rod 24 on the top of heat dissipation vest 4, and hydraulic rod 24's output fixedly connected with rises the bottom that holds up strip 25, it is L shape to play the vertical section of holding up strip 25, play sliding connection between support strip 25 and the sealed cock board 21, when hydraulic rod 24 begins the work, hydraulic rod 24's rising has promoted the support strip 25 and has risen, sealed cock board 21 rises when rising, wherein sealed cock board 21 rises has received the influence of location slide rail 22 and spacing slider 23 in-process, concrete performance is: the ascending movement of the limiting slide block 23 needs to move along the positioning slide rail 22 as a track, the bottom end of the positioning slide rail 22 inclines upwards, the limiting slide block 23 can also drive the sealing plug plate 21 to move upwards along the track, the sealing plug plate moves to the tail end of the inclined plane, the limiting slide block 23 ascends linearly inside the positioning slide rail 22, the sealing plug plate 21 is pushed to be embedded into the heat dissipation through groove 18, the upper end and the lower end are isolated, and the hot air flow at the upper end cannot be transmitted to the lower end;

when the hydraulic push rod 24 descends, the lifting and supporting strip 25 is driven to descend, wherein the bottom ends of the lifting and supporting strip 25 and the sealing plug plate 21 are influenced by the clamping piece, the lifting and supporting strip 25 is driven to descend, the sealing plug plate 21 starts to incline and descend after descending linearly, when the sealing plug plate descends to the lowest end, the protruding strip at the upper end of the sealing plug plate 21 and the heat dissipation through groove 18 are staggered, the heat dissipation through groove 18 corresponds to the notch at the upper end of the sealing plug plate 21, when heat dissipation is carried out, heat at the upper end of a chip is blown by the first heat dissipation fan 6, outside air is blown into the testing base 2, air flows through the connecting strip 13 and the upper end of the temperature measuring frame 10, the heat at the upper end is taken away, hot air flows through the heat dissipation through groove 18 to the bottom end of the heat dissipation vest 4, circulation of the air is accelerated through rotation of the second heat dissipation fan 8, the speed of air circulation is higher, a good heat dissipation air channel is formed under the cooperation of the first heat dissipation fan 6 and the second heat dissipation fan 8, and the heat dissipation effect is also more excellent.

Inside sealed can be guaranteed to this test seat during operation for inner space is also narrower and small, and inside heat is difficult for running off, consequently can better control the temperature that the chip can bear when the pressure test, and the temperature measurement is also more accurate, and the interference that receives is also littleer, tests the wind channel that the back heat dissipation adopted good heat exchange, and the speed of circulation of air is also fast, and the effect of cooling is also more showing.

It should be noted that, in this document, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (10)

1. The utility model provides a chip heat dissipation test seat with heat measurement function, includes upper cover (1), its characterized in that: the bottom end of the upper sealing cover (1) is connected with a testing base (2), the upper end of the testing base (2) is connected with a lifting rod (5), the upper end of the testing base (2) is connected with a fixing block (3), the bottom end of the testing base (2) is connected with a heat dissipation waistcoat (4), one side of the testing base (2) is fixedly connected with a first heat dissipation fan (6), the upper end of the heat dissipation waistcoat (4) is provided with heat dissipation fins (7), and the bottom end of the heat dissipation waistcoat (4) is provided with a second heat dissipation fan (8);

a detection seat (12) is embedded and connected in the test base (2), a chip clamping plate (9) is installed at the upper end of the detection seat (12), a temperature measuring frame (10) is connected at the upper end of the chip clamping plate (9), a reserved groove (15) is formed in the inner side of the chip clamping plate (9), a heat conduction wrapping sheet (14) is connected at the upper end of the temperature measuring frame (10), a temperature measuring sensor (19) is embedded in the heat conduction wrapping sheet (14), and a heat conduction sheet (20) is fixedly connected at the top end of the heat conduction wrapping sheet (14);

the inside embedding of test base (2) is connected with division board (17), heat dissipation logical groove (18) have been seted up to the upper end of division board (17), fixedly connected with location slide rail (22) on the inner wall of test base (2), the inside embedding of location slide rail (22) is connected with spacing slider (23), the sealed chock plate (21) of one end fixedly connected with of spacing slider (23), the bottom of sealed chock plate (21) is connected with plays and holds in the palm strip (25), the bottom setting that plays to hold in the palm strip (25) is connected with hydraulic push rod (24).

2. The chip heat dissipation test socket with the heat measurement function according to claim 1, wherein: the upper sealing cover (1) is connected with the testing base (2) through a lifting adjusting rod (5), the lifting adjusting rod (5) penetrates through the inside of a fixing block (3) at the upper end of the upper sealing cover (1), the fixing block (3) is in sliding connection with the lifting adjusting rod (5), and sealing gaskets are fixedly connected to the inner wall of the upper sealing cover (1) and the top surface of the testing base (2).

3. The chip heat dissipation test socket with the heat measurement function according to claim 1, wherein: the bottom of test base (2) is provided with a set of through-hole, the inside of test base (2) and heat dissipation vest (4) is linked together, heat dissipation vest (4) are made for the copper-nickel alloy.

4. The chip heat dissipation test socket with the heat measurement function according to claim 1, wherein: the utility model discloses a chip clamp plate, including detect both sides fixedly connected with linking strip (13) of seat (12), be connected with link (11) on the top surface of detecting seat (12), the inside embedding of chip splint (9) is connected with a set of axostylus axostyle, and the axostylus axostyle embedding is in the inside of link (11), swing joint between link (11) and chip splint (9), install PIN needle (16) on the inner wall of detecting seat (12).

5. The chip heat dissipation test socket with the function of measuring heat according to claim 1, wherein: temperature measurement frame (10) even equidistance install the upper end in chip splint (9), the inside embedding of a set of logical groove in chip splint (9) upper end has a set of temperature measurement frame (10), temperature measurement frame (10) set up to frame structure, temperature measurement frame (10) are made for the copper metal.

6. The chip heat dissipation test socket with heat measurement function according to claim 5, wherein: two ends of the inner wall of the temperature measuring sensor (19) are attached to the inner part of the heat conduction wrapping sheet (14), and the top end of the heat conduction sheet (20) is also closely attached to the inner wall of the temperature measuring frame (10).

7. The chip heat dissipation test socket with the heat measurement function according to claim 1, wherein: sealed cock board (21) are provided with two sets ofly altogether, and are two sets of sealed cock board (21) keep same height, and are two sets of sealed cock board (21) are respectively through limiting slide block (23) embedding in the inside of two sets of location slide rails (22), sealed cock board (21) are made for the silica gel material, the abrupt strip that sealed cock board (21) set up leads to groove (18) looks adaptation with the heat dissipation, sealed cock board (21) set up the position of abrupt strip and all wrap up the rubber pad.

8. The chip heat dissipation test socket with the function of measuring heat according to claim 1, wherein: the positioning slide rails (22) are arranged in a bent shape, and the bending directions of the two groups of positioning slide rails (22) on the same side are completely opposite.

9. The chip heat dissipation test socket with the function of measuring heat according to claim 1, wherein: the sealing plug plate is characterized in that limiting sliding blocks (23) are fixedly connected to two sides of the sealing plug plate (21), the limiting sliding blocks (23) are embedded in the positioning sliding rails (22), and the limiting sliding blocks (23) are connected with the positioning sliding rails (22) in a sliding mode.

10. The chip heat dissipation test socket with the heat measurement function according to claim 1, wherein: fixedly connected with hydraulic rod (24) on the top of heat dissipation vest (4), and the output fixedly connected with of hydraulic rod (24) rises the bottom of holding in the palm strip (25), the vertical section that rises and holds in the palm strip (25) is L shape, sliding connection between rising and holding in the palm strip (25) and sealed cock board (21).

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