CN211923700U

CN211923700U - Linear accelerator machine room capable of improving safety

Info

Publication number: CN211923700U
Application number: CN202020370130.5U
Authority: CN
Inventors: 万晨耀
Original assignee: Wuxi Light University Architectural Design And Research Institute Co ltd
Current assignee: Wuxi Light University Architectural Design And Research Institute Co ltd
Priority date: 2020-03-21
Filing date: 2020-03-21
Publication date: 2020-11-13
Anticipated expiration: 2030-03-21

Abstract

The utility model belongs to the technical field of the technique of radiation protection room and specifically relates to an improve linear accelerator computer lab of security is related to, it includes the wall body, linear accelerator places district and computer lab mobile shield door, the wall body includes labyrinth outer wall and labyrinth interior wall, it is equipped with labyrinth mobile shield door to slide on the labyrinth interior wall, labyrinth interior wall is close to the side slope setting of wall body mobile shield door, be equipped with the sliding block on the side that labyrinth interior wall is close to wall body mobile shield door, be equipped with the constant head tank on the sliding block bottom surface, it wears to be equipped with the locating pin to slide in the constant head tank, be equipped with positioning spring in the constant head tank, labyrinth mobile shield door's side is equipped with the sliding groove, be equipped with on the lateral wall in sliding groove with locating pin complex guiding groove, labyrinth mobile shield door is through the sliding groove, sliding. The utility model discloses have the protective capacities who promotes the computer lab entrance, improve the effect of the security of linear accelerator computer lab.

Description

Linear accelerator machine room capable of improving safety

Technical Field

The utility model belongs to the technical field of the technique of radiation protection room and specifically relates to a linear accelerator computer lab of improvement security is related to.

Background

The radiation protection room is a protection building, can be used as a medical room for body detection or remote external irradiation treatment in hospitals and the like, and blocks X-ray radiation or electron radiation beams, so that the influence of radiation on the outside of the medical room is reduced, medical staff in the medical room is protected, and the probability of injury to the body of the medical staff is reduced.

Chinese patent with publication number CN110685474A discloses a linear accelerator machine room, including the wall body, the labyrinth, linear accelerator places district and computer lab removal shield door, the wall body includes labyrinth outer wall, labyrinth inner wall, the side shield wall, main shield wall and the secondary shield wall that links to each other with main shield wall, computer lab removal shield door is located the computer lab entrance, the inlet of labyrinth intercommunication linear accelerator placing area and computer lab, linear accelerator places the district and is located the region of being enclosed by labyrinth inner wall, the side shield wall, main shield wall and secondary shield wall, one side slip that labyrinth inner wall department is close to linear accelerator placing area is equipped with labyrinth removal shield door, the direction of sliding of labyrinth removal shield door is perpendicular to first side shield wall.

The above prior art solutions have the following drawbacks: when the linear accelerator operates, the gamma rays generated are transmitted along straight lines and have extremely strong penetrating power, and when the linear accelerator is close to a machine room inlet, the machine room movable shielding door and the labyrinth movable shielding door have poor protective capability on the gamma rays, so that the gamma rays generated at the machine room inlet are easy to leak, and the safety of a machine room of the linear accelerator is reduced.

SUMMERY OF THE UTILITY MODEL

Not enough to prior art exists, the utility model aims at providing an improve linear accelerator computer lab of security, it has the protective capacities who promotes the computer lab entrance, improves the effect of the security of linear accelerator computer lab.

The above object of the present invention is achieved by the following technical solutions:

a linear accelerator machine room capable of improving safety comprises a wall body, a linear accelerator placing area and a machine room moving shielding door, wherein the wall body comprises a labyrinth outer wall and a labyrinth inner wall, the labyrinth inner wall is provided with the labyrinth moving shielding door in a sliding manner, the labyrinth inner wall is arranged close to the side face of the wall body moving shielding door in a tilted manner, the width of the side face of the labyrinth inner wall close to the labyrinth outer wall is smaller than that of the other side, the side face of the labyrinth inner wall close to the wall body moving shielding door is provided with a sliding block, the bottom face of the sliding block is provided with a positioning groove, a positioning pin is arranged in the positioning groove in a sliding manner, a positioning spring for driving the positioning pin to slide back to the bottom of the positioning groove is arranged in a tilted manner, the edge of the bottom face of the positioning pin back to the labyrinth inner wall is higher than a notch of the positioning groove, and the edge of, the side of labyrinth mobile shield door is equipped with the groove of sliding, be equipped with on the lateral wall in groove of sliding with locating pin complex guiding groove, labyrinth mobile shield door is through sliding groove, sliding block and labyrinth interior wall sliding fit, the side that labyrinth mobile shield door is close to computer lab mobile shield door is on a parallel with computer lab mobile shield door.

Through adopting above-mentioned technical scheme, establish labyrinth mobile shield door carriage on the side that the wall body mobile shield door is close to the labyrinth interior wall, can place the space in district to linear accelerator after minimizing labyrinth mobile shield door opens and occupy, guarantee linear accelerator can conveniently immigrate linear accelerator and place the district, labyrinth mobile shield door is through the side and the wall body laminating that are close to computer lab mobile shield door, thickened labyrinth mobile shield door can promote computer lab entrance computer lab mobile shield door and labyrinth mobile shield door to the protective capacities of ray, improve the security of linear accelerator computer lab.

The present invention may be further configured in a preferred embodiment as: the wall body is provided with a first sensor and a second sensor which are used for monitoring the opening and closing states of the machine room movable shielding door and the labyrinth movable shielding door respectively, and the first sensor and the second sensor are connected in series to be connected into a control circuit.

Through adopting above-mentioned technical scheme, through setting up sensor one and sensor two, can conveniently know the open and close state of computer lab mobile shield door and labyrinth mobile shield door, and with sensor one and sensor two access control circuit, can avoid linear accelerator to start the condition emergence that leads to the ray to reveal under the condition that computer lab mobile shield door or labyrinth mobile shield door do not close.

The present invention may be further configured in a preferred embodiment as: the labyrinth mobile shielding door is characterized in that a roller is rotatably erected on the bottom surface of the labyrinth mobile shielding door, and the axis of the roller is perpendicular to the side surface of the labyrinth inner wall close to the wall mobile shielding door.

Through adopting above-mentioned technical scheme, erect the roller bearing on the bottom surface of labyrinth mobile shield door, can reduce the sliding resistance of labyrinth mobile shield door, and then make things convenient for switching labyrinth mobile shield door.

The present invention may be further configured in a preferred embodiment as: the ground of the linear accelerator placing area is higher than the bottom surface of the labyrinth mobile shielding door, and the ground of the linear accelerator placing area is obliquely arranged close to the side surface of the labyrinth mobile shielding door to form a guide inclined surface.

Through adopting above-mentioned technical scheme, place the ground in district with linear accelerator and set up to be higher than the bottom surface of labyrinth removal shield door, can reduce the probability that the ray passed from the gap between labyrinth removal shield door bottom surface and the ground, improve the security of linear accelerator computer lab, set up the guide inclined plane and can conveniently push linear accelerator by linear accelerator computer lab into linear accelerator and place the district.

The present invention may be further configured in a preferred embodiment as: one side that the labyrinth removes the shield door and is close to the labyrinth outer wall is equipped with and pushes away the groove, it has the handle to push away the inslot internal rotation frame, the rotation axis of handle sets up along vertical direction.

Through adopting above-mentioned technical scheme, set up on the labyrinth removes the shield door and push away the groove to set up the handle at pushing away the inslot rotation, can promote labyrinth and remove the shield door through the handle and slide when switching labyrinth removes the shield door, play the effect that makes things convenient for the switching labyrinth to remove the shield door.

The present invention may be further configured in a preferred embodiment as: the labyrinth outer wall is provided with a wire hole for a pipeline and an electric wire to pass through in a penetrating manner, the wire hole is positioned on one side of the labyrinth inner wall back to the linear accelerator placing area, and the wire hole comprises oblique sections at two ends and a vertically arranged connecting section.

Through adopting above-mentioned technical scheme, set up the line hole of constituteing by putting section and linkage segment to one side, arrange the electric wire in the linac computer lab tied in a bundle in the line hole to reduce the probability that the ray wore out from the labyrinth outer wall through the line hole, and then improve the security of linac computer lab.

The present invention may be further configured in a preferred embodiment as: the improved motor room shield door is characterized in that a sliding groove is formed in the bottom surface of the machine room movable shield door, the sliding groove is formed in the length direction of the machine room movable shield door, a base is arranged on the ground of a machine room inlet, the machine room movable shield door is in sliding fit with the base through the sliding groove, a nut seat is arranged on the top surface of the machine room movable shield door, the axis of the nut seat is parallel to the length direction of the machine room movable shield door, a screw rod penetrates through the nut seat, a screw rod rotating frame is arranged on a wall body, and a driving motor used for driving the screw rod to rotate is arranged on the.

Through adopting above-mentioned technical scheme, establish computer lab mobile shield door at the computer lab entrance through spout and base carriage to it is rotatory through driving motor drive screw, and then drives computer lab mobile shield door through the nut seat and slides, can conveniently switching computer lab mobile shield door.

The present invention may be further configured in a preferred embodiment as: the sliding groove is internally provided with a sliding wheel in a rotating mode, the axis of the sliding wheel is parallel to the thickness direction of the machine room movable shielding door, and the machine room movable shielding door is in sliding fit with the base through the sliding wheel.

Through adopting above-mentioned technical scheme, the pulley is erect in the spout internal rotation, can reduce the computer lab when mobile shield door slides and the base between the frictional force, and then make things convenient for switching computer lab mobile shield door.

To sum up, the utility model discloses a following at least one useful technological effect:

1. the labyrinth mobile shield door sliding frame is arranged on the side surface, close to the wall body mobile shield door, of the inner wall of the labyrinth, so that the protection capability of the machine room mobile shield door at the inlet of the machine room and the labyrinth mobile shield door on rays can be improved, and the safety of the machine room of the linear accelerator is improved;

2. by arranging the first sensor and the second sensor, the effect of avoiding ray leakage caused by starting the linear accelerator under the condition that the mobile shield door of the machine room or the labyrinth mobile shield door is not closed can be achieved;

3. through setting up the line hole, can play the effect that improves the security of linear accelerator computer lab.

Drawings

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

FIG. 2 is a schematic structural diagram of the inner wall of the labyrinth in the embodiment;

FIG. 3 is a schematic structural diagram of the labyrinth moving screen door in the embodiment;

FIG. 4 is a schematic view of a structure of a string hole in the embodiment;

fig. 5 is a schematic connection diagram of the machine room moving shield door and the first side shield wall in the embodiment.

In the figure, 1, a wall body; 11. a first side shield wall; 111. a first sensor; 112. accommodating grooves; 113. a second sensor; 12. a second side shield wall; 13. a main shield wall; 14. a secondary shield wall; 15. a labyrinth outer wall; 151. a wire hole; 152. a slanting section; 153. a connecting section; 16. an inner wall of the labyrinth; 2. a sliding block; 21. positioning a groove; 22. positioning pins; 23. a positioning spring; 3. moving the shielding door in a labyrinth way; 31. a sliding groove; 32. a guide groove; 33. pushing the groove; 34. a handle; 35. a rolling groove; 36. a roller; 4. a linear accelerator placement area; 41. a guide ramp; 5. a machine room mobile shielding door; 51. a chute; 52. a pulley; 53. a base; 54. a nut seat; 6. a drive motor; 61. an ear plate; 62. a screw.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Example (b):

referring to fig. 1, for the utility model discloses an improve linear accelerator computer lab of security, including wall body 1, wall body 1 includes first side shielding wall 11, second side shielding wall 12, main shielding wall 13, inferior shielding wall 14, labyrinth outer wall 15 and labyrinth inner wall 16, and wherein main shielding wall 13 is connected with inferior shielding wall 14, and the two and second side shielding wall 12, labyrinth outer wall 15, first side shielding wall 11 connect gradually, and all wall bodies 1 are concrete wall 1, and the 1 homogeneous body casting of each section wall body forms linear accelerator computer lab main part. The main shielding wall 13 and the secondary shielding wall 14 are both parallel to the labyrinth outer wall 15, and the main shielding wall 13 and the secondary shielding wall 14 are arranged in parallel.

Referring to fig. 1, the labyrinth inner wall 16 is disposed parallel to the labyrinth outer wall 15, and the labyrinth inner wall 16 is located inside the linear accelerator room and on a side close to the labyrinth outer wall 15. The side surface of the labyrinth inner wall 16 close to the first side shielding wall 11 is obliquely arranged, and the width of the side surface of the labyrinth inner wall 16 close to the labyrinth outer wall 15 is smaller than that of the other side. The side that labyrinth inner wall 16 is close to first side shield wall 11 slides and is provided with labyrinth movement shield door 3, and the cross section of labyrinth movement shield door 3 is trapezoidal, and the side that labyrinth movement shield door 3 is close to labyrinth outer wall 15 is on a parallel with the side of labyrinth outer wall 15, and the side that labyrinth movement shield door 3 is close to first side shield wall 11 is on a parallel with the side of first side shield wall 11, and labyrinth movement shield door 3 is the lead door.

Referring to fig. 1 and 2, a sliding block 2 is bolted to the side surface of the labyrinth inner wall 16 close to the first side shielding wall 11, the sliding block 2 is arranged in a full length along the horizontal direction, the sliding block 2 is a lead block, three positioning grooves 21 are arranged on the bottom surface of the sliding block 2, and the three positioning grooves 21 are uniformly arranged along the length direction of the sliding block 2. The cross-section of the positioning groove 21 is circular, a positioning pin 22 is slidably arranged in the positioning groove 21 in a penetrating manner, and a positioning spring 23 is glued between the top surface of the positioning pin 22 and the bottom of the positioning groove 21. The bottom surface of the positioning pin 22 is obliquely arranged, the edge of the bottom surface of the positioning pin 22, which faces away from the labyrinth inner wall 16, is higher than the notch of the positioning groove 21, and the edge of the bottom surface of the positioning pin 22, which faces towards the labyrinth inner wall 16, is lower than the notch of the positioning groove 21.

Referring to fig. 2 and 3, a sliding groove 31 is provided on one side of the labyrinth moving shielding door 3 close to the labyrinth inner wall 16, the sliding groove 31 is parallel to the length direction of the sliding block 2, the sliding groove 31 is adapted to the sliding block 2, and the labyrinth moving shielding door 3 is in sliding fit with the labyrinth inner wall 16 through the sliding groove 31 and the sliding block 2. The lateral wall that the sliding groove 31 is close to ground is equipped with guiding groove 32, guiding groove 32 and locating pin 22's bottom adaptation, and guiding groove 32 runs through the both ends of sliding groove 31 along the length direction of sliding groove 31.

Referring to fig. 3, a push groove 33 is formed in one side of the labyrinth moving shield door 3 away from the labyrinth inner wall 16, a handle 34 is hinged in the push groove 33, and the rotation axis of the handle 34 is arranged in the vertical direction.

Referring to fig. 1 and 3, a group of rolling grooves 35 are formed in the bottom surface of the labyrinth moving shielding door 3, the rolling grooves 35 are uniformly arranged along the length direction of the side surface of the labyrinth moving shielding door 3 close to the labyrinth inner wall 16, the axis of each rolling groove 35 is perpendicular to the side surface of the labyrinth inner wall 16 close to the labyrinth moving shielding door 3, and the cross section of each rolling groove 35 is a major arc. A roller 36 is rotatably arranged in each rolling groove 35, and the labyrinth moving shielding door 3 is abutted against the ground through the side surface of the roller 36.

Referring to fig. 1, a receiving groove 112 is formed in a side surface of the first side shielding wall 11 close to the labyrinth moving shielding door 3, a second sensor 113 for monitoring an opening and closing state of the labyrinth moving shielding door 3 is arranged in the receiving groove 112, and the second sensor 113 abuts against a probe of the second sensor when the labyrinth moving shielding door 3 is closed. The second sensor 113 is provided, so that the open-close state of the labyrinth moving shielding door 3 can be conveniently known.

Referring to fig. 1, a region defined by the labyrinth inner wall 16, the labyrinth moving shielding door 3, the first side shielding wall 11, the secondary shielding wall 14, the main shielding wall 13 and the second side shielding wall 12 is a linac placing area 4, the ground of the linac placing area 4 is higher than the bottom surface of the labyrinth moving shielding door 3, and the ground of the linac placing area 4 is obliquely arranged near the side surface of the labyrinth moving shielding door 3 to form a guide inclined surface 41. The ground that makes linear accelerator place district 4 is higher than the bottom surface of labyrinth mobile shield door 3, can reduce the probability that the ray passed from the gap between labyrinth mobile shield door 3 bottom surface and the ground, improves the security of linear accelerator computer lab, sets up guide inclined plane 41, can be when installation linear accelerator, conveniently push or release linear accelerator and place district 4.

Referring to fig. 1 and 4, a thread hole 151 is formed at one side of the labyrinth outer wall 15 close to the labyrinth inner wall 16, and the thread hole 151 communicates with both sides of the labyrinth outer wall 15. The two ends of the wire hole 151 are oblique sections 152, the axes of the two oblique sections 152 are parallel to each other, a connecting section 153 is arranged between the two oblique sections 152 for communication, and the connecting section 153 is arranged along the vertical direction. The arrangement of the wire hole 151 formed by the inclined section 152 and the connecting section 153 can reduce the probability that rays penetrate out of the labyrinth outer wall 15 through the wire hole 151, and the safety of a linear accelerator machine room is improved.

Referring to fig. 5, the entry of linear accelerator computer lab is located first side shielding wall 11, and first side shielding wall 11 is equipped with base 53 in the inside one side of linear accelerator computer lab dorsad, and base 53 bolt is subaerial, and the axis of base 53 is on a parallel with the length direction of first side shielding wall 11 side, and the sliding rack is equipped with computer lab removal shield door 5 on base 53, and computer lab removal shield door 5 is close to the side of first side shielding wall 11 and laminates with first side shielding wall 11, and computer lab removal shield door 5 is plumbous door.

Referring to fig. 5, the length of the machine room mobile shield door 5 is greater than the entrance width of the linear accelerator machine room, a sliding groove 51 is formed in the bottom surface of the machine room mobile shield door 5, the sliding groove 51 is arranged along the length direction of the machine room mobile shield door 5, a group of pulleys 52 are rotatably erected in the sliding groove 51, the pulleys 52 are uniformly arranged along the length direction of the sliding groove 51, and the axis of each pulley 52 is perpendicular to the thickness direction of the machine room mobile shield door 5. The machine room moving shielding door 5 is in sliding fit with the base 53 through the pulley 52, and the bottom surface of the machine room moving shielding door 5 is lower than the upper surface of the base 53.

Referring to fig. 1 and 5, the side of the first side shielding wall 11 facing away from the interior of the linear accelerator room is bolted with two lug plates 61 and a driving motor 6, the connecting line between the two lug plates 61 is parallel to the length direction of the mobile shielding door 5 of the room, and the two lug plates 61 are respectively located at two sides of the entrance of the linear accelerator room. A screw 62 is rotatably arranged between the two lug plates 61, and the axis of the screw 62 is parallel to the thickness direction of the lug plates 61. The output end of the driving motor 6 is connected with the screw 62 through a coupling, so that the screw 62 can be driven to rotate. Two nut seats 54 are bolted on the top surface of the machine room mobile shielding door 5, the two nut seats 54 are respectively positioned at two ends of the top surface of the machine room mobile shielding door 5 in the length direction, and the two nut seats 54 are in threaded fit with the screw 62.

Referring to fig. 1 and 5, a first sensor 111 for monitoring the opening and closing state of the machine room movable shielding door 5 is bolted to the side surface of the first side shielding wall 11, which faces away from the interior of the linear accelerator machine room, and the first sensor 111 abuts against a probe of the first sensor when the machine room movable shielding door 5 is closed. Utilize sensor 111, can conveniently know the open and close state of computer lab mobile shield door 5, sensor 111 and sensor two 113 access control circuit can avoid linear accelerator to start the condition emergence that leads to the ray to reveal under the condition that computer lab mobile shield door 5 or labyrinth mobile shield door 3 were not closed.

The implementation principle of the embodiment is as follows: after the linear accelerator machine room is built, the machine room movable shielding door 5 and the labyrinth movable shielding door 3 are opened, and the linear accelerator can be pushed into the linear accelerator placing area 4 through the guide inclined plane 41. After the machine room movable shielding door 5 and the labyrinth movable shielding door 3 are completely closed, the control circuit of the linear accelerator can be opened, and the scheme has the effect of improving the safety of the machine room of the linear accelerator.

The embodiment of this specific implementation mode is the preferred embodiment of the present invention, not limit according to this the utility model discloses a protection scope, so: all equivalent changes made according to the structure, shape and principle of the utility model are covered within the protection scope of the utility model.

Claims

1. The utility model provides an improve linear accelerator computer lab of security, places district (4) and computer lab removal shield door (5) including wall body (1), linear accelerator, wall body (1) is including labyrinth outer wall (15) and labyrinth inner wall (16), it is equipped with labyrinth removal shield door (3) to slide on labyrinth inner wall (16), its characterized in that: the utility model discloses a fan shield door, including labyrinth way interior wall (16), labyrinth way interior wall (16) are close to the side slope setting of wall body (1) mobile shield door, and labyrinth way interior wall (16) are close to the side width that labyrinth way outer wall (15) and are less than the width of opposite side, be equipped with glide block (2) on the side that labyrinth way interior wall (16) are close to wall body (1) mobile shield door, be equipped with constant head tank (21) on glide block (2) bottom surface, it wears to be equipped with locating pin (22) to slide in constant head tank (21), be equipped with in constant head tank (21) and be used for ordering about locating pin (22) to the gliding positioning spring (23) of constant head tank (21) tank bottom, the bottom surface slope setting of locating pin (22), the border that constant head tank (21) are higher than to labyrinth way interior wall (16) is dorsad in the bottom surface of locating pin (22), the border of, the side of labyrinth moving shield door (3) is equipped with groove (31) that slides, be equipped with on the lateral wall of groove (31) that slides with locating pin (22) complex guiding groove (32), labyrinth moving shield door (3) are through groove (31), the sliding block (2) and labyrinth interior wall (16) sliding fit that slides, the side that labyrinth moving shield door (3) are close to computer lab moving shield door (5) is on a parallel with computer lab moving shield door (5).

2. The linear accelerator room for improving the safety of the machine room according to claim 1, wherein: the device is characterized in that a first sensor (111) and a second sensor (113) which are used for monitoring the opening and closing states of the machine room movable shielding door (5) and the labyrinth movable shielding door (3) are arranged on the wall body (1) respectively, and the first sensor (111) and the second sensor (113) are connected in series to a control circuit.

3. The linear accelerator room for improving the safety of the machine room according to claim 1, wherein: the labyrinth mobile shielding door is characterized in that a roller (36) is rotatably erected on the bottom surface of the labyrinth mobile shielding door (3), and the axis of the roller (36) is perpendicular to the side surface of the labyrinth inner wall (16) close to the wall body (1) mobile shielding door.

4. The linear accelerator room for improving safety of claim 3, wherein: the ground of linear accelerator placing area (4) is higher than the bottom surface of labyrinth mobile shielding door (3), the side slope setting that the ground of linear accelerator placing area (4) is close to labyrinth mobile shielding door (3) forms guide inclined plane (41).

5. The linear accelerator room for improving the safety of the machine room according to claim 1, wherein: one side that labyrinth removes shield door (3) is close to labyrinth outer wall (15) is equipped with and pushes away groove (33), push away the interior rotation of groove (33) and erect handle (34), the axis of rotation of handle (34) sets up along vertical direction.

6. The linear accelerator room for improving the safety of the machine room according to claim 1, wherein: wear to be equipped with on labyrinth outer wall (15) and be used for supplying pipeline and electric wire through line hole (151), line hole (151) are located labyrinth inner wall (16) one side of placing district (4) to linear accelerator dorsad, line hole (151) include the oblique section (152) of putting and the linkage segment (153) of vertical setting at both ends.

7. The linear accelerator room for improving the safety of the machine room according to claim 1, wherein: be equipped with spout (51) on the bottom surface of computer lab mobile shield door (5), spout (51) lead to long the setting along the length direction of computer lab mobile shield door (5), the subaerial base (53) that is equipped with of computer lab entry, computer lab mobile shield door (5) are through spout (51) and base (53) sliding fit, be equipped with nut seat (54) on the top surface of computer lab mobile shield door (5), the axis of nut seat (54) is on a parallel with the length direction of computer lab mobile shield door (5), wear to be equipped with screw rod (62) in nut seat (54), screw rod (62) rotating turret is established on wall body (1), be equipped with on wall body (1) and be used for driving screw rod (62) pivoted driving motor (6).

8. The linear accelerator room for improving safety of claim 7, wherein: a pulley (52) is rotatably erected in the sliding groove (51), the axis of the pulley (52) is parallel to the thickness direction of the machine room moving shielding door (5), and the machine room moving shielding door (5) is in sliding fit with the base (53) through the pulley (52).