An adjustable railway section communication device

Abstract

This invention discloses an adjustable railway section communication device, belonging to the field of communication equipment installation technology. It includes: a main pressure plate for connecting to a communication box; a secondary pressure plate connected to the main pressure plate, both being semi-circular structures capable of fitting onto the outside of a utility pole; and a pressure roller elastically connected to the outside of the main and secondary pressure plates, maintaining the stability of the communication box relative to the utility pole through friction between the pressure roller and the pole. A split-type traveling assembly allows the traveling wheel, fitted onto the outside of the stud, to make close contact with the outer circumference of the utility pole. During the communication box's ascent, the contact between the traveling wheel and the utility pole remains stable. During the separation of the two traveling wheels, the traveling wheel easily disengages from the outer wall of the utility pole, thus providing space for the main and secondary pressure plates to fully conform to the outside of the utility pole, ensuring the communication box is stably installed on the utility pole.

Description

Technical Field

[0001] This invention relates to the field of communication equipment installation technology, and in particular to an adjustable railway section communication device. Background Technology

[0002] Railway section communication equipment is a communication device designed specifically for railway sections (i.e., the railway line area between two stations) and equipped with parameter adjustment functions. It is mainly used to ensure the transmission of information between trains and the ground, and between trains within the railway section, so as to ensure the safety and efficiency of railway transportation.

[0003] Currently, communication equipment is mostly installed on utility poles on both sides of the railway. When encountering obstacles, the position of the communication box needs to be raised to ensure signal coverage of the entire track area and avoid signal blind spots caused by terrain obstruction. In the actual installation process, workers often have to climb to heights and use clamps to connect the communication equipment to the utility poles, making the overall installation quite inconvenient.

[0004] Therefore, it is necessary to provide an adjustable railway section communication device to solve the above-mentioned technical problems. Summary of the Invention

[0005] The purpose of this invention is to provide an adjustable railway section communication device to solve the problem mentioned in the background art that the existing communication devices require workers to climb to heights and connect them to utility poles with clamps, making the overall installation inconvenient.

[0006] Based on the above ideas, the present invention provides the following technical solution: an adjustable railway section communication device, comprising:

[0007] The main pressure plate is used to connect to the communication box;

[0008] A secondary pressure plate is connected to the main pressure plate. Both the main pressure plate and the secondary pressure plate are semi-circular structures and can be sleeved on the outside of the utility pole.

[0009] The pressure roller is elastically connected to the outside of the main pressure plate and the auxiliary pressure plate. The friction between the pressure roller and the utility pole can maintain the stability of the communication box relative to the utility pole.

[0010] A rotating shaft is rotatably connected to the communication box. Studs are arranged on both the upper and lower sides of the rotating shaft, and the rotating shaft can drive the studs to rotate synchronously.

[0011] The split-type walking assembly is mounted on a stud and can rotate synchronously with the stud. When the stud drives the split-type walking assembly to rotate in the forward direction, the communication box can move upward along the utility pole. When the rotating shaft drives the stud to rotate in the reverse direction, the split-type walking assembly located on the stud is in a separated state, so that the main pressure plate and the auxiliary pressure plate have space to fit against the utility pole.

[0012] As a further aspect of the present invention: both ends of the main pressure plate and the auxiliary pressure plate extend outward to form connecting ear plates, and the outer side of the connecting ear plates is fixedly provided with threaded sleeves. The connecting post located at the connecting ear plate passes through the two threaded sleeves and engages with their threads. During the rotation of the connecting post, the main pressure plate and the auxiliary pressure plate can be brought closer or further away from each other, and the rotating shaft and the connecting post are in a transmission cooperation.

[0013] As a further aspect of the present invention: the split-type walking assembly includes two walking wheels sleeved on a stud, and a sleeve is fixedly provided on the outer end face of the walking wheel. The sleeve is sleeved on the outside of the stud and threadedly connected to the stud. During the rotation of the stud, the two walking wheels can move closer to or further away from each other.

[0014] As a further embodiment of the present invention: multiple sets of limiting grooves are evenly opened on the outer circumferential surface of the sleeve, a limiting plate is fixedly provided on the communication box, the sleeve passes through a pre-set through hole on the limiting plate, a limiting block that cooperates with the limiting groove is elastically connected to the inner wall of the through hole, and a slope is provided at one end of the limiting block extending to the outer side of the limiting plate.

[0015] As a further aspect of the present invention: the end of the rotating shaft near the connecting column is fitted with a driving bevel gear through a one-way bearing, and the outer side of the connecting column is fitted with a driven bevel gear that meshes with the driving bevel gear.

[0016] As a further embodiment of the present invention: guide frames are fixedly provided on the outer sides of both the secondary pressure plate and the main pressure plate, and sliders are elastically connected inside the guide frames. The connecting shaft at the end of the pressure roller is rotatably engaged with the slider through a first one-way bearing.

[0017] As a further aspect of the present invention: the main pressure plate and the communication box are connected by a fixing rod.

[0018] As a further aspect of the present invention: both the main pressure plate and the auxiliary pressure plate are provided with through slots for the pressure rollers to pass through.

[0019] As a further aspect of the present invention: the outer surface of the connecting column and at the position of the two threaded sleeves are provided with two sections of first external threads with opposite directions.

[0020] As a further aspect of the present invention: two sections of second external threads with opposite directions are provided on the outer circumference of the stud at the positions of the two sleeves.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows: by setting a split walking component, the walking wheel sleeved on the outside of the stud can make close contact with the outer circumference of the utility pole, and the contact between the walking wheel and the utility pole can remain stable during the climbing process of the communication box. During the separation of the two walking wheels, the walking wheel can easily disengage from the outer wall of the utility pole, thereby providing space for the main pressure plate and the secondary pressure plate to fully fit against the outside of the utility pole, so that the communication box can be stably installed on the utility pole. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0023] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 This is a schematic diagram of the main pressure plate and the auxiliary pressure plate of the present invention.

[0025] Figure 3 This is a schematic diagram of the fit between the rotating shaft and the stud of the present invention;

[0026] Figure 4 This is a schematic diagram of the structure of the split-type walking assembly of the present invention;

[0027] Figure 5 This is a schematic diagram of the two sets of walking wheels after separation according to the present invention;

[0028] Figure 6 This is a schematic diagram of the interaction between the rotating shaft and the driving bevel gear of the present invention;

[0029] Figure 7 This is the present invention. Figure 4 Enlarged schematic diagram of part A;

[0030] Figure 8 This is a schematic diagram of the engagement between the protrusion and the groove of the present invention;

[0031] Figure 9 This is a schematic diagram of the two sets of wheels of the present invention when they are in contact;

[0032] In the diagram: 1. Utility pole; 2. Communication box; 201. Fixed pole; 3. Traveling wheel; 301. Sleeve; 3011. Limiting groove; 302. Arc surface; 4. Connecting column; 401. Strip groove; 5. Main pressure plate; 6. Secondary pressure plate; 7. Screw sleeve; 8. Slider; 9. Guide frame; 10. Stud; 11. Pressure roller; 12. Limiting spring; 13. Driven bevel gear; 1301. Protrusion; 14. Ring seat; 15. Transmission unit; 16. Limiting plate; 17. Mounting seat; 18. Connecting rod; 19. Pressure rod; 1901. Protrusion; 1902. Conical surface; 20. Driving bevel gear; 2001. Slot; 21. Telescopic rod; 22. Rotating shaft; 23. Limiting block; 2301. Inclined surface. Detailed Implementation

[0033] like Figures 1-9 As shown, an adjustable railway section communication device includes a main pressure plate 5 and a secondary pressure plate 6 that cooperate with each other. A communication box 2 with communication components is fixedly installed on one side of the main pressure plate 5. Both the main pressure plate 5 and the secondary pressure plate 6 are semi-circular structures. The main pressure plate 5 and the secondary pressure plate 6 can be fixed to the outside of the utility pole 1 by bolts, thereby installing the communication box 2.

[0034] When there are obstacles in the area, the height of the communication box 2 needs to be increased to avoid signal blind spots caused by terrain obstruction. Based on this, the solution has pressure rollers 11 elastically installed on the main pressure plate 5 and the auxiliary pressure plate 6. When the main pressure plate 5 and the auxiliary pressure plate 6 are fitted on the outside of the utility pole 1, the pressure rollers 11 are pressed against the outside of the utility pole 1 by the elastic force, so as to facilitate the adjustment of the height of the communication box 2.

[0035] Furthermore, a rotating shaft 22 is installed on the side of the communication box 2 near the main pressure plate 5, and the rotating shaft 22 is driven to rotate by a motor inside the communication box 2. Studs 10 are arranged on both the upper and lower sides of the rotating shaft 22, and a split-type walking component is installed on the stud 10. The stud 10 and the rotating shaft 22 are connected through a transmission unit 15. Initially, the split-type walking component installed on the stud 10 is in a close-up state and located in the middle position of the stud 10. During the process of the rotating shaft 22 driving the stud 10 to rotate in the forward direction, the friction between the split-type walking component and the utility pole 1 can drive the communication box 2 to move upward along the utility pole 1. When a certain height is reached, the rotating shaft 22 drives the stud 10 to rotate in the reverse direction. During this process, the split-type walking component located on the stud 10 can be in a separated state, thereby providing space for the main pressure plate 5 and the secondary pressure plate 6 to fit against the utility pole 1.

[0036] To ensure that the main pressure plate 5 and the secondary pressure plate 6 can approach each other and completely fit against the outside of the utility pole 1, this design includes a connecting post 4. Figure 2As shown, both ends of the main pressure plate 5 and the auxiliary pressure plate 6 extend outward to form connecting lugs. The outer side of the connecting lugs is fixedly provided with threaded sleeves 7, and the connecting post 4 passes through the two threaded sleeves 7 and engages with their threads. Specifically, the outer surface of the connecting post 4 and located at the positions of the two threaded sleeves 7 are provided with two sections of first external threads with opposite directions, so that the main pressure plate 5 and the auxiliary pressure plate 6 can move closer or further away from each other during the rotation of the connecting post 4. In actual use, the rotating shaft 22 and the connecting post 4 are driven together to drive the connecting post 4 to rotate.

[0037] The split-type walking assembly includes two walking wheels 3 sleeved on the stud 10, combined with... Figure 2 , Figure 5 as well as Figure 9 As shown, the outer surface of the traveling wheel 3 is an arc surface 302 structure, which allows the traveling wheel 3 to fit against the outer circumference of the utility pole 1. This structure provides a large contact area between the traveling wheel 3 and the utility pole 1, thereby stably driving the communication box 2 upwards. Figure 9 As can be seen, when the two wheels 3 are in contact, they are in a state of driving the communication box 2 to climb, while when the two wheels 3 are in a state of... Figure 5 In the separated state shown, the main pressure plate 5 and the auxiliary pressure plate 6 are in a position to fully fit with the utility pole 1, thereby enabling the communication box 2 to be stably installed on the utility pole 1.

[0038] Furthermore, a sleeve 301 is fixedly provided on the outer end face of the walking wheel 3, and the sleeve 301 is sleeved on the outside of the stud 10 and threadedly connected to the stud 10. Specifically, two sections of second external threads with opposite directions are provided on the outer circumferential surface of the stud 10 and at the positions of the two sleeves 301, so that the two walking wheels 3 can move closer or further away from each other during the rotation of the stud 10, thereby realizing two working states of the split walking component.

[0039] Furthermore, multiple sets of limiting grooves 3011 are evenly formed on the outer circumferential surface of the sleeve 301. The limiting grooves 3011 are arranged along the axis of the sleeve 301, while a limiting plate 16 is fixedly installed on the communication box 2. The sleeve 301 passes through a pre-set through hole on the limiting plate 16, combined with... Figure 4 , Figure 7As shown, a limiting block 23 that mates with the limiting groove 3011 is elastically connected to the inner wall of the through hole. One end of the limiting block 23 extending to the outer side of the limiting plate 16 has an inclined surface 2301. When the traveling wheels 3 are in a climbing state, the two sets of traveling wheels 3 are in contact with each other and are in the middle position of the stud 10. At this time, as the rotating shaft 22 synchronously drives the stud 10 to rotate, the side edge of the limiting groove 3011 contacts the inclined surface 2301 on the limiting block 23, allowing the stud 10 to drive the sleeve 301 to rotate forward relative to the limiting plate 16. During this process, the traveling wheels 3 drive the communication box 2 to move upward through the friction between themselves and the utility pole 1. When the communication box 2 rises to a specified height, the rotating shaft 22 drives the stud 10 to rotate in the opposite direction. At this time, the cooperation between the limiting block 23 and the limiting groove 3011 prevents the stud 10 from driving the sleeve 301 to rotate, allowing the two traveling wheels 3 to separate during the rotation of the stud 10. See the attached diagram for details. Figure 5 As shown, at this time, the main pressure plate 5 and the auxiliary pressure plate 6 are in a position to fully fit with the utility pole 1.

[0040] Combination Figures 2-3 As shown, the end of the rotating shaft 22 near the connecting column 4 is fitted with a driving bevel gear 20 through a one-way bearing, while the outer side of the connecting column 4 is fitted with a driven bevel gear 13 that meshes with the driving bevel gear 20, thereby driving the connecting column 4 to rotate, thereby causing the main pressure plate 5 and the auxiliary pressure plate 6 to move closer to each other.

[0041] During actual installation, the main pressure plate 5 and the auxiliary pressure plate 6 are fitted onto the outside of the utility pole 1, ensuring that the pressure roller 11 and the traveling wheel 3 are in close contact with the outer circumference of the utility pole 1. Initially, the two sets of traveling wheels 3 are positioned as follows: Figure 9 The state shown allows for a large contact area between the walking wheels 3 and the utility pole 1. When the rotating shaft 22 drives the stud 10 to rotate synchronously, since the two sets of walking wheels 3 are already in contact, the stud 10 can drive the two sets of walking wheels 3 that are in contact to rotate, thereby driving the communication box 2 to climb along the utility pole 1. During this process, the rotating shaft 22 does not drive the active bevel gear 20 to rotate.

[0042] After the communication box 2 climbs to its position, the motor drives the rotating shaft 22 to rotate in the opposite direction. During this process, the rotating shaft 22 drives the stud 10 to rotate in the opposite direction. Through the cooperation of the limiting block 23 and the limiting groove 3011, the stud 10 cannot drive the sleeve 301 and the traveling wheels 3 to rotate in the opposite direction. Therefore, under the condition of thread engagement, the reverse rotation of the stud 10 can cause the two sets of traveling wheels 3 to gradually separate. (Refer to...) Figure 5As shown, as the two sets of walking wheels 3 gradually separate, the walking wheels 3 also lose contact with the utility pole 1, thus preparing the main pressure plate 5 and the auxiliary pressure plate 6 to fit against the outside of the utility pole 1. At the same time, as the rotating shaft 22 rotates in the opposite direction, the rotating shaft 22 can drive the active bevel gear 20 to rotate through the one-way bearing, thereby using the meshing of the active bevel gear 20 and the driven bevel gear 13 to drive the connecting column 4 to rotate. As described above, during the rotation of the connecting column 4, the main pressure plate 5 and the auxiliary pressure plate 6 can approach each other and completely fit against the outside of the utility pole 1, which helps to maintain the stability of the communication box 2.

[0043] In summary, this device, through its split-type walking assembly, allows the walking wheel 3, which is fitted onto the outside of the stud 10, to make close contact with the outer circumference of the utility pole 1. During the climbing process of the communication box 2, the contact between the walking wheel 3 and the utility pole 1 remains stable. During the separation of the two walking wheels 3, the walking wheel 3 can easily detach from the outer wall of the utility pole 1, thereby providing space for the main pressure plate 5 and the secondary pressure plate 6 to fully fit against the outside of the utility pole 1, so that the communication box 2 can be stably installed on the utility pole 1.

[0044] Combination Figures 3-7 As shown, a connecting rod 18 is provided between a set of sleeves 301 and a rotating shaft 22. Specifically, the sleeve 301 can pass through the connecting rod 18 and rotate with it through a bearing, while the rotating shaft 22 passes through the connecting rod 18 and the connecting rod 18 can move relative to the rotating shaft 22 along the axial direction of the rotating shaft 22. A pressure rod 19 is slidably arranged inside the rotating shaft 22. The end of the pressure rod 19 near the active bevel gear 20 has a conical surface 1902 structure. A telescopic rod 21 is elastically connected to the outer wall of the rotating shaft 22. The telescopic rod 21 can move along the diameter direction of the rotating shaft 22. Initially, the bottom end of the telescopic rod 21 rests on the conical surface 1902 of the pressure rod 19.

[0045] The inner wall of the active bevel gear 20 has a groove 2001 that mates with the telescopic rod 21. A protrusion 1901 is fixedly provided on the outer wall of the pressure rod 19. The protrusion 1901 extends to the outside of the rotating shaft 22 and is located on one side of the connecting rod 18. In actual use, when the rotating shaft 22 rotates in the opposite direction and drives the two sets of traveling wheels 3 away from each other, the connecting rod 18 can move outward with the traveling wheels 3, allowing the connecting rod 18 to push the pressure rod 19 relative to the telescopic rod 21 through the protrusion 1901, and through the conical surface 1902... The compression of the telescopic rod 21 can cause the telescopic rod 21 to move outward, so that the end of the telescopic rod 21 away from the rotating shaft 22 can be inserted into the slot 2001. Therefore, in the process of removing the communication box 2, it is only necessary to rotate the rotating shaft 22 in the forward direction. At this time, the rotating shaft 22 can drive the active bevel gear 20 to rotate through the cooperation of the telescopic rod 21 and the slot 2001. Then, through the meshing of the active bevel gear 20 and the driven bevel gear 13, the connecting column 4 is driven to rotate, so that the main pressure plate 5 and the secondary pressure plate 6 can gradually separate.

[0046] Reference Figures 1-2 As shown, both the main pressure plate 5 and the auxiliary pressure plate 6 have through slots for the pressure roller 11 to pass through, and connecting shafts are fixedly installed at both ends of the pressure roller 11. Guide frames 9 are fixedly installed on the outer surfaces of both the auxiliary pressure plate 6 and the main pressure plate 5. A slider 8 is slidably mounted inside the guide frame 9. The end of the connecting shaft away from the pressure roller 11 is rotatably engaged with the slider 8 via a first one-way bearing. Figure 2 As can be seen, the crossbar on the slider 8 passes through the guide frame 9 and slides with it. A limit spring 12 is provided between the slider 8 and the end of the guide frame 9. Through the force of the limit spring 12, the pressure roller 11 can press against the outside of the utility pole 1. The pressure roller 11 rotates in one direction, so that the pressure roller 11 can only roll upward along the utility pole 1. With this structure, when the walking wheel 3 drives the communication box 2 to climb to the specified height, the sliding friction between the pressure roller 11 and the utility pole 1 can maintain the stability of the communication box 2.

[0047] The end of the connecting post 4 away from the screw sleeve 7 is left with a certain distance from the communication box 2. A strip groove 401 is opened on the outer circumference of the connecting post 4, and a protrusion 1301 that slides with the strip groove 401 is fixedly provided on the inner wall of the driven bevel gear 13. Through this structure, the driven bevel gear 13 can slide relative to the connecting post 4 along its axis while driving the connecting post 4 to rotate synchronously.

[0048] Both ends of the stud 10 are rotatably mounted with support rods, and the support rods are fixedly connected to the communication box 2. The outer side of the driven bevel gear 13 is rotatably fitted with an annular seat 14 through a bearing. The annular seat 14 is fixedly connected to the support rod through a bracket. The main pressure plate 5 and the communication box 2 are fixedly connected through a fixing rod 201.

[0049] A mounting base 17 is fixedly installed on the inner side of the communication box 2. The rotating shaft 22 passes through the mounting base 17 and rotates with it through a bearing. The motor installed in the communication box 2 is connected to the rotating shaft 22 through a gear set. The transmission unit 15 between the rotating shaft 22 and the stud 10 can be a belt or a chain.

[0050] Reference Figure 6 As shown, the telescopic rod 21 consists of a sliding sleeve and a sliding rod that slides within the sliding sleeve. A spring is fixedly installed between the sliding rod and the inner end face of the sliding sleeve. The rotating shaft 22 has a stepped hole that mates with the pressure rod 19, allowing the pressure rod 19 to slide within the stepped hole. In addition, the rotating shaft 22 has a slot that communicates with the stepped hole, allowing the protrusion 1901 to pass through the slot and move relative to the rotating shaft 22. A retaining ring is fixedly fitted at one end of the telescopic rod 21 inside the stepped hole, and a return spring is fixedly installed between the retaining ring and the inner wall of the stepped hole.

[0051] from Figure 7 As can be seen, the limiting block 23 slides in the mounting groove on the inner wall of the through hole, and a first spring is fixedly installed between the inner end face of the mounting groove and the limiting block 23.

[0052] The above-disclosed examples are merely preferred embodiments of this application, intended to facilitate understanding and implementation by those skilled in the art. However, they cannot be used to limit the scope of this application. Therefore, equivalent variations made within the scope of this application are still within the scope of this application.

Claims

1. An adjustable railway section communication device, characterized in that, include: The main pressure plate (5) is used to connect to the communication box (2); The secondary pressure plate (6) is connected to the main pressure plate (5). Both the main pressure plate (5) and the secondary pressure plate (6) are semi-circular structures and can be sleeved on the outside of the utility pole (1). The pressure roller (11) is elastically connected to the outside of the main pressure plate (5) and the auxiliary pressure plate (6). The friction between the pressure roller (11) and the utility pole (1) can keep the communication box (2) stable relative to the utility pole (1). A rotating shaft (22) is rotatably connected to the communication box (2). Studs (10) are arranged on both the upper and lower sides of the rotating shaft (22), and the rotating shaft (22) can drive the studs (10) to rotate synchronously. The split-type walking component is installed on the stud (10) and can rotate synchronously with the stud (10). When the stud (10) drives the split-type walking component to rotate in the forward direction, the communication box (2) can move upward along the utility pole (1). When the rotating shaft (22) drives the stud (10) to rotate in the reverse direction, the split-type walking component located on the stud (10) is in a separated state, so that the main pressure plate (5) and the auxiliary pressure plate (6) have space to fit with the utility pole (1). Both ends of the main pressure plate (5) and the auxiliary pressure plate (6) extend outward to form connecting ear plates, and the outer side of the connecting ear plates is fixedly provided with threaded sleeves (7). The connecting column (4) located at the connecting ear plate passes through the two threaded sleeves (7) and engages with their threads. During the rotation of the connecting column (4), the main pressure plate (5) and the auxiliary pressure plate (6) can be made to move closer or further away from each other. The rotating shaft (22) and the connecting column (4) are in a transmission cooperation. The split-type walking assembly includes two walking wheels (3) sleeved on the stud (10). A sleeve (301) is fixedly provided on the outer end face of the walking wheel (3). The sleeve (301) is sleeved on the outside of the stud (10) and threadedly connected to the stud (10). During the rotation of the stud (10), the two walking wheels (3) can move closer or further away from each other. Multiple sets of limiting grooves (3011) are evenly opened on the outer circumference of the sleeve (301). A limiting plate (16) is fixedly installed on the communication box (2). The sleeve (301) passes through a pre-set through hole on the limiting plate (16). A limiting block (23) that cooperates with the limiting groove (3011) is elastically connected to the inner wall of the through hole. A slope (2301) is provided at one end of the limiting block (23) extending to the outside of the limiting plate (16).

2. The adjustable railway section communication equipment according to claim 1, characterized in that: The rotating shaft (22) is fitted with a drive bevel gear (20) at one end near the connecting column (4) via a one-way bearing, and a driven bevel gear (13) that meshes with the drive bevel gear (20) is fitted on the outside of the connecting column (4).

3. The adjustable railway section communication equipment according to claim 1, characterized in that: Guide frames (9) are fixedly installed on the outer sides of both the secondary pressure plate (6) and the main pressure plate (5). A slider (8) is elastically connected inside the guide frame (9). The connecting shaft at the end of the pressure roller (11) is rotated with the slider (8) through the first one-way bearing.

4. The adjustable railway section communication equipment according to claim 1, characterized in that: The main pressure plate (5) and the communication box (2) are connected by a fixing rod (201).

5. An adjustable railway section communication device according to claim 1, characterized in that: Both the main pressure plate (5) and the auxiliary pressure plate (6) are provided with through slots for the pressure roller (11) to pass through.

6. An adjustable railway section communication device according to claim 2, characterized in that: The outer surface of the connecting column (4) and at the position of the two threaded sleeves (7) are provided with two sections of first external threads with opposite directions.

7. An adjustable railway section communication device according to claim 1, characterized in that: The stud (10) has two sections of second external threads with opposite directions on its outer circumference at the positions of the two sleeves (301).

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