Portable oxygen cylinder transportation device for emergency use
Patent Information
- Application Number
- CN202522586520.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-05
- Publication Date
- 2026-10-09
- Estimated Expiration
- 2035-12-05
AI Technical Summary
现有的氧气瓶推车大都单次只能转运一个氧气瓶，能够满足急症室日常需要，但是，急症室确实存在多瓶搬运的场景，如：应对群体性事件（如交通事故、火灾），多个病人同时需要高流量氧疗，要快速将多个氧气瓶运送到指定集结区域，而单次单个氧气瓶转运则无法满足急救需求，但是，此种情况并非日常频繁发生，若为所有推车都标配双瓶固定架会造成体积浪费、通行不便、成本增加，基于此，提供一种能够调节的急诊用氧气瓶便携运输装置
通过设置移动车组件、可调式限位组件，可实现单个或两个氧气瓶的运输操作，两种模式独立发挥作用，灵活性更强，且能够更好的满足急诊室的使用需求。
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Figure CN224829103U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of oxygen cylinder transportation devices, specifically a portable transportation device for emergency oxygen cylinders. Background Technology
[0002] In the emergency room, oxygen is a critical life support resource for rescue and treatment. It is mainly supplied in two ways: central oxygen supply system and portable oxygen cylinders. Among them, the oxygen cylinders used in the emergency room are also known as oxygen cylinders, which are containers for storing medical oxygen under high pressure. Oxygen cylinder carts are the most commonly used and standard transport tool in hospitals, especially suitable for medium- to long-distance transport between emergency rooms and wards, and to examination departments (such as CT rooms). The main components of an oxygen cylinder cart include: Main frame: made of sturdy metal (such as stainless steel), with a wide and stable chassis at the bottom and swivel casters with brakes (at least two of the casters have brakes). Fastening devices: Velcro / elastic straps, chains or belts with buckles, adjustable bottle clamps or calipers, etc.; Most existing oxygen cylinder carts can only transport one oxygen cylinder at a time, which can meet the daily needs of the emergency room. However, there are indeed scenarios in the emergency room where multiple cylinders need to be transported, such as when dealing with mass incidents (such as traffic accidents or fires) where multiple patients need high-flow oxygen therapy at the same time. It is necessary to quickly transport multiple oxygen cylinders to a designated assembly area, and transporting a single oxygen cylinder at a time cannot meet the emergency needs. However, this situation does not occur frequently in daily life. If all carts are equipped with double cylinder fixing racks as standard, it will result in wasted space, inconvenience in passage, and increased costs. Based on this, an adjustable portable transport device for emergency oxygen cylinders is provided. Utility Model Content
[0003] The purpose of this utility model is to provide a portable transportation device for emergency oxygen cylinders in order to solve the problems mentioned above.
[0004] To achieve the above objectives, this utility model provides the following technical solution: a portable transport device for emergency oxygen cylinders, comprising a mobile vehicle assembly consisting of a rectangular frame, a triangular frame, movable wheels, and handles. The triangular frame is fixed to the bottom rear end of the rectangular frame, the movable wheels are rotatably mounted on both sides of the triangular frame, and the handles are symmetrically fixed to the top two sides of the rectangular frame. The mobile vehicle assembly also includes a transverse cylinder and a fixing connector. The horizontal cylinder is fixed to the vertical part of the rectangular frame, and the fixing connector is fixed to the rear end of the vertical part of the rectangular frame and is vertically offset from the horizontal cylinder; The rectangular frame is connected to an adjustable limiting component via a transverse cylinder. The adjustable structure of the adjustable limiting component is used to realize the transportation operation of one or two oxygen cylinders. The rectangular frame is equipped with a partition component and a locking component through a fixed connector. After the adjustable limiting component is unfolded, the partition component divides the placement area formed by the adjustable limiting component, so as to realize the independent storage of two oxygen cylinders. The locking component is used to lock the adjustable limiting component and the dividing component in their retracted and expanded states.
[0005] As a further embodiment of this utility model: the adjustable limiting component includes an inverted U-shaped side frame, a J-shaped crossbar, a limiting circular block, and an E-shaped base plate; Multiple J-shaped crossbars are arranged vertically and are fixedly connected to the inverted U-shaped side frame; the E-shaped base plate is fixed to the bottom of the inverted U-shaped side frame. The inverted U-shaped side frame, J-shaped crossbar, and E-shaped base plate are symmetrically arranged in two sets around the rectangular frame. The two sets of symmetrical J-shaped crossbars are vertically staggered, and the two sets of symmetrical E-shaped base plates interlock horizontally. The J-shaped crossbar passes through the transverse tube and is fixedly connected to the limiting block, and the J-shaped crossbar is slidably connected to the transverse tube. The transverse tube and the corresponding inverted U-shaped side frame are located on both sides of the rectangular frame. When the two sets of inverted U-shaped side frames, J-shaped crossbars, and E-shaped base plates are close to each other, they are used to limit the placement of an oxygen cylinder; When the two sets of inverted U-shaped side frames, J-shaped crossbars, and E-shaped base plates are far apart from each other, they are used to create a large space for placing two oxygen cylinders.
[0006] As a further embodiment of this utility model: the separating component includes a straight slotted partition and a connecting rod; Multiple fixed connectors are evenly arranged along the vertical trajectory of the rectangular frame, and the bottom of the other fixed connectors, except for the topmost fixed connector, is fixed with a fixed post. The number of straight groove type partitions matches the number of fixed connectors and they are respectively distributed below multiple fixed connectors. The straight groove type partitions are slidably sleeved with the fixed columns, and one side of multiple straight groove type partitions is connected and fixed by connecting rods. The straight slotted partition and connecting rod are arranged laterally at the rear end of the rectangular frame, which does not affect the transportation operation of a single oxygen cylinder; When the two sets of inverted U-shaped side frames, J-shaped crossbars, and E-shaped base plates are far apart from each other, the straight slotted partition and connecting rod rotate to be perpendicular to the rectangular frame and move forward to the middle of the two inverted U-shaped side frames to form a placement area for placing two oxygen cylinders.
[0007] As a further embodiment of this utility model: the locking assembly includes a top block, a locking rod, a locking bolt, and a concave pressure block; The top block is located above the topmost fixed connector, and the locking rod is fixed to both sides of the bottom of the top block and passes through the topmost fixed connector; The two horizontal cylinders at the top of the two vertical sections of the rectangular frame are provided with first locking holes, and the bottoms of the two locking rods are respectively inserted into the two first locking holes; The J-shaped crossbar has two horizontally distributed second locking holes. When the second locking hole is aligned with the first locking hole, the locking rod completely passes through the second locking hole to achieve the overall position locking of the inverted U-shaped side frame, the J-shaped crossbar, and the E-shaped base plate. The locking bolts are distributed on the top of the top block and pass through the top block, the fixed connector, the top straight groove type partition and are threadedly connected to the concave pressure block. The concave pressure block is sleeved on the outside of the bottom of the top straight groove type partition. The locking bolts are tightened to lock the state of the separation component and the adjustable limit component.
[0008] As a further improvement of this utility model: the topmost fixed connector has a through hole for the locking rod and the locking bolt to pass through, the fixed connector has an "Ω" shaped cross section when viewed from above, and the fixed column and the locking bolt are distributed in the middle of the "Ω" shaped protrusion.
[0009] As a further improvement of this utility model: the horizontal cylinders on the two vertical parts of the rectangular frame are vertically staggered and correspond one-to-one with the distribution positions of the J-shaped crossbars, and the vertical parts of the rectangular frame are formed with arc-shaped avoidance parts to avoid the J-shaped crossbars.
[0010] Compared with the prior art, the beneficial effects of this utility model are: By setting up mobile cart components and adjustable limit components, the transportation of one or two oxygen cylinders can be realized. The two modes can function independently, which is more flexible and can better meet the needs of emergency room use. Attached Figure Description
[0011] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a structural schematic diagram from the rear end view of this utility model; Figure 3 This is a structural schematic diagram of the adjustable limiting component and the separating component of this utility model in their unfolded state; Figure 4 This is a structural exploded view of the adjustable limiting component and the separating component of this utility model; Figure 5 This is a disassembled schematic diagram of the locking component of this utility model.
[0012] In the diagram: 1. Moving vehicle assembly; 101. Rectangular frame; 102. Horizontal cylinder; 103. First locking hole; 104. Arc-shaped clearance part; 105. Triangular frame; 106. Moving wheel; 107. Fixed connector; 108. Through hole; 109. Fixed column; 110. Handle; 2. Adjustable limit assembly; 201. Inverted U-shaped side frame; 202. J-shaped crossbar; 203. Second locking hole; 204. Limiting round block; 205. E-shaped base plate; 3. Divider assembly; 301. Straight groove type partition; 302. Connecting rod; 4. Locking assembly; 401. Top block; 402. Locking rod; 403. Locking bolt; 404. Concave pressure block. Detailed Implementation
[0013] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0014] Please see Figures 1-5 In this embodiment of the utility model, a portable transport device for emergency oxygen cylinders includes a mobile vehicle assembly 1 consisting of a rectangular frame 101, a tripod 105, casters 106, and handles 110. The tripod 105 is fixed to the bottom rear end of the rectangular frame 101, the casters 106 are rotatably mounted on both sides of the tripod 105, and the handles 110 are symmetrically fixed to the top two sides of the rectangular frame 101. The mobile vehicle assembly 1 also includes a transverse cylinder 102 and a fixing connector 107. The horizontal cylinder 102 is fixed to the vertical part of the rectangular frame 101, and the fixed connector 107 is fixed to the rear end of the vertical part of the rectangular frame 101 and is vertically offset from the horizontal cylinder 102. The rectangular frame 101 is connected to an adjustable limiting component 2 via a transverse cylinder 102. The adjustable structure of the adjustable limiting component 2 is used to realize the transportation operation of one or two oxygen cylinders. The rectangular frame 101 is equipped with a partition component 3 and a locking component 4 via a fixed connector 107. After the adjustable limit component 2 is unfolded, the partition component 3 divides the placement area formed by the adjustable limit component 2, thereby achieving independent storage of two oxygen cylinders. The locking component 4 is used to lock the adjustable limit component 2 and the partition component 3 in their retracted and expanded states. Adjustable limiting assembly 2 includes an inverted U-shaped side frame 201, a J-shaped crossbar 202, a limiting block 204, and an E-shaped base plate 205; Multiple J-shaped crossbars 202 are vertically arranged and fixedly connected to the inverted U-shaped side frame 201; the E-shaped base plate 205 is fixed to the bottom of the inverted U-shaped side frame 201. Two sets of inverted U-shaped side frames 201, J-shaped crossbars 202, and E-shaped base plates 205 are symmetrically arranged around the rectangular frame 101. The two sets of symmetrical J-shaped crossbars 202 are vertically staggered, and the two sets of symmetrical E-shaped base plates 205 protrusions interlock horizontally. J-shaped crossbar 202 passes through transverse cylinder 102 and is fixedly connected to limiting block 204. J-shaped crossbar 202 is slidably connected to transverse cylinder 102. Transverse cylinder 102 and corresponding inverted U-shaped side frame 201 are located on both sides of rectangular frame 101. When the two sets of inverted U-shaped side frames 201, J-shaped crossbars 202, and E-shaped base plates 205 are close to each other, they are used to limit the placement of an oxygen cylinder. When the two sets of inverted U-shaped side frames 201, J-shaped crossbars 202, and E-shaped base plates 205 are far apart from each other, they are used to create a large space for placing two oxygen cylinders. The partition assembly 3 includes a straight slotted partition 301 and a connecting rod 302; Multiple fixed connectors 107 are evenly arranged along the vertical trajectory of the rectangular frame 101. Except for the top fixed connector 107, the bottom of the other fixed connectors 107 is fixed with a fixed post 109. The number of straight slotted partitions 301 and fixed connectors 107 are matched and distributed below the multiple fixed connectors 107. The straight slotted partitions 301 are slidably sleeved with the fixed columns 109. One side of the multiple straight slotted partitions 301 is connected and fixed by connecting rods 302. The straight slotted partition 301 and the connecting rod 302 are arranged horizontally at the rear end of the rectangular frame 101, which does not affect the transportation operation of a single oxygen cylinder; When the two sets of inverted U-shaped side frames 201, J-shaped crossbars 202, and E-shaped base plates 205 are far apart from each other, the straight slot type partition 301 and connecting rod 302 rotate to be perpendicular to the rectangular frame 101 and move forward to the middle of the two inverted U-shaped side frames 201 to form a placement area for placing two oxygen cylinders. Locking assembly 4 includes a top block 401, a locking rod 402, a locking bolt 403, and a concave pressure block 404; The top block 401 is located above the topmost fixed connector 107, and the locking rod 402 is fixed to both sides of the bottom of the top block 401 and passes through the topmost fixed connector 107; The two horizontal cylinders 102 at the top of the two vertical parts of the rectangular frame 101 are provided with first locking holes 103, and the bottoms of the two locking rods 402 are respectively inserted into the two first locking holes 103; Two horizontally distributed second locking holes 203 are provided on the J-shaped crossbar 202. When the second locking hole 203 is aligned with the first locking hole 103, the locking rod 402 completely passes through the second locking hole 203 to realize the overall position locking of the inverted U-shaped side frame 201, J-shaped crossbar 202, and E-shaped base plate 205. Locking bolts 403 are distributed on the top of the top block 401 and pass through the top block 401, the fixed connector 107, the top straight groove type partition 301 and are threadedly connected to the concave pressure block 404. The concave pressure block 404 is sleeved on the bottom outer side of the top straight groove type partition 301. Tightening the locking bolts 403 is used to lock the state of the partition component 3 and the adjustable limit component 2.
[0015] In this embodiment, it should be noted that the moving method of this mobile cart assembly 1 is the same as the moving method of oxygen cylinder carts commonly found on the market. When the mobile cart assembly 1 is placed vertically, the moving wheels 106 do not contact the ground. When moving, the moving wheels 106 contact the ground and move, at which time the entire device is tilted. Under normal circumstances, the adjustable limiting component 2 is in the retracted state: that is, the two sets of inverted U-shaped side frames 201, J-shaped crossbars 202, and E-shaped base plates 205 are close to each other, and the separating component 3 is horizontally stored at the rear end of the rectangular frame 101 (e.g. Figure 1 , 2 At this point, the space formed by the two sets of inverted U-shaped side frames 201, J-shaped crossbars 202, and E-shaped base plates 205 is just enough to place an oxygen cylinder, which facilitates the transportation of a single oxygen cylinder. (It should be noted that after the oxygen cylinder is placed in the middle position of the two sets of inverted U-shaped side frames 201, J-shaped crossbars 202, and E-shaped base plates 205, the front ends of the two inverted U-shaped side frames 201 can be used to bind and limit the oxygen cylinder through Velcro, elastic straps, chains, etc. This structure is the conventional structure of existing oxygen cylinder trolleys, so it is not shown in the figure.) If two oxygen cylinders need to be transported in a single trip, the procedure is as follows: First, loosen the locking bolt 403. At this time, the locking bolt 403 releases the pressure on the top block 401, and the concave pressure block 404 releases the pressure on the top straight groove partition 301. Then, manually pull the top block 401 and the locking rod 402 upward as a whole, so that the locking rod 402 separates from one of the second locking holes 203 on the J-shaped crossbar 202, that is, release the lock on the J-shaped crossbar 202. At this time, the inverted U-shaped side frame 201, the J-shaped crossbar 202 and the E-shaped base plate 205 can be manually pulled outward as a whole. Finally, the limiting round block 204 fits with the transverse cylinder 102. At this time, the other second locking hole 203 on the J-shaped crossbar 202 is aligned with the first locking hole 103. After the two sets of inverted U-shaped side frames 201, J-shaped crossbars 202, and E-shaped base plates 205 have all been moved outward, the top block 401 and locking rod 402 are lowered. At this time, the locking rod 402 is inserted into another second locking hole 203 to lock the two sets of inverted U-shaped side frames 201, J-shaped crossbars 202, and E-shaped base plates 205 in the unfolded state. (It should be noted that the locking rod 402 is in the shape of a "ㄣ", and the vertical part of the top of the two locking rods 402 is at a different height, so that the two locking rods 402 can adapt to the height difference of the two transverse cylinders 102.) After the adjustable limiting component 2 is deployed, first pull the connecting rod 302 to move it horizontally, causing multiple straight slot partitions 301 to move synchronously. After the inner wall end of the straight slot of the straight slot partition 301 contacts the fixed column 109, rotate the partition component 3 ninety degrees (it should be noted that the concave pressure block 404 rotates synchronously). Then, push the partition component 3 towards the front end. Finally, the straight slot partition 301 is located in the middle of the two inverted U-shaped side frames 201 (e.g., Figure 3 Then, tighten the locking bolt 403; At this time, the unfolded adjustable limiting component 2 and the straight slot partition 301 form two placement areas, which can independently place the two oxygen cylinders.
[0016] Please refer to this carefully. Figures 1-5 The topmost fixed connector 107 has a through hole 108 for the locking rod 402 and the locking bolt 403 to pass through. The fixed connector 107 has an “Ω” shaped cross section when viewed from above. The fixed post 109 and the locking bolt 403 are distributed in the middle of the “Ω” shaped protrusion.
[0017] In this embodiment, the “Ω”-shaped structure of the fixed connector 107 ensures that the partition component 3 can be stored and unfolded without interfering with the locking rod 402.
[0018] Please refer to this carefully. Figures 1-3 The horizontal cylinders 102 on the two vertical parts of the rectangular frame 101 are vertically staggered and correspond one-to-one with the distribution position of the J-shaped crossbars 202. The vertical parts of the rectangular frame 101 are formed with arc-shaped clearance parts 104 to avoid the J-shaped crossbars 202.
[0019] In this embodiment: the staggered arrangement of the horizontal cylinders 102 on both sides and the J-shaped crossbars 202 can ensure that the horizontal movement of the two sets of J-shaped crossbars 202 does not interfere with each other. The arc-shaped clearance part 104 ensures that the movement of the J-shaped crossbar 202 does not interfere with the rectangular frame 101, thus ensuring smooth operation of the device. It should also be noted that the outer side of the part of the J-shaped crossbar 202 that does not contact the transverse cylinder 102 can be wrapped with a protective layer to accommodate the outer diameter of the transverse cylinder 102 and prevent hard impacts on the oxygen cylinder due to the difference in the outer wall size of the transverse cylinder 102 and the J-shaped crossbar 202.
[0020] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.
Claims
1. A portable transport device for emergency oxygen cylinders, comprising a mobile vehicle assembly (1) consisting of a rectangular frame (101), a tripod (105), casters (106), and handles (110), wherein the tripod (105) is fixed to the bottom rear end of the rectangular frame (101), the casters (106) are rotatably mounted on both sides of the tripod (105), and the handles (110) are symmetrically fixed to both sides of the top of the rectangular frame (101), characterized in that, The mobile vehicle assembly (1) also includes a transverse cylinder (102) and a fixed connector (107). The horizontal cylinder (102) is fixed to the vertical part of the rectangular frame (101), and the fixed connector (107) is fixed to the rear end of the vertical part of the rectangular frame (101) and is vertically offset from the horizontal cylinder (102); The rectangular frame (101) is connected to an adjustable limiting component (2) via a transverse cylinder (102). The adjustable structure of the adjustable limiting component (2) is used to realize the transportation operation of one or two oxygen cylinders. The rectangular frame (101) is equipped with a partition component (3) and a locking component (4) through a fixed connector (107). After the adjustable limiting component (2) is unfolded, the partition component (3) divides the placement area formed by the adjustable limiting component (2) to achieve independent storage of two oxygen cylinders. The locking component (4) is used to lock the adjustable limiting component (2) and the separating component (3) in their retracted and expanded states.
2. The portable transport device for emergency oxygen cylinders according to claim 1, characterized in that, The adjustable limiting component (2) includes an inverted U-shaped side frame (201), a J-shaped crossbar (202), a limiting round block (204), and an E-shaped base plate (205); The J-shaped crossbars (202) are arranged vertically in multiple ways and are fixedly connected to the inverted U-shaped side frame (201); the E-shaped base plate (205) is fixed to the bottom of the inverted U-shaped side frame (201); The inverted U-shaped side frame (201), J-shaped crossbar (202), and E-shaped base plate (205) are symmetrically arranged in two sets around the rectangular frame (101), and the two sets of symmetrical J-shaped crossbars (202) are vertically staggered, and the two sets of symmetrical E-shaped base plates (205) have protruding plates that interlock horizontally. The J-shaped crossbar (202) passes through the transverse tube (102) and is fixedly connected to the limiting block (204), and the J-shaped crossbar (202) is slidably connected to the transverse tube (102). The transverse tube (102) and the corresponding inverted U-shaped side frame (201) are located on both sides of the rectangular frame (101). When the two sets of inverted U-shaped side frames (201), J-shaped crossbars (202), and E-shaped base plates (205) are close to each other, they are used to limit the placement of an oxygen cylinder; When the two sets of inverted U-shaped side frames (201), J-shaped crossbars (202), and E-shaped base plates (205) are far apart from each other, they are used to form a large space for placing two oxygen cylinders.
3. A portable transport device for emergency oxygen cylinders according to claim 2, characterized in that, The partition assembly (3) includes a straight slotted partition (301) and a connecting rod (302); Multiple fixed connectors (107) are evenly arranged along the vertical trajectory of the rectangular frame (101), and the bottom of the other fixed connectors (107) except for the topmost fixed connector (107) is fixed with a fixed post (109). The number of straight slotted partitions (301) and fixed connectors (107) are matched and distributed below the multiple fixed connectors (107). The straight slotted partitions (301) are slidably sleeved with the fixed columns (109). One side of the multiple straight slotted partitions (301) is connected and fixed by connecting rods (302). The straight slotted partition (301) and connecting rod (302) are arranged horizontally at the rear end of the rectangular frame (101), which does not affect the transportation operation of a single oxygen cylinder; When the two sets of inverted U-shaped side frames (201), J-shaped crossbars (202), and E-shaped base plates (205) are far apart from each other, the straight slotted partition (301) and connecting rod (302) rotate to be perpendicular to the rectangular frame (101) and move forward to the middle of the two inverted U-shaped side frames (201) to form a placement area for placing two oxygen cylinders.
4. A portable transport device for emergency oxygen cylinders according to claim 3, characterized in that, The locking assembly (4) includes a top block (401), a locking rod (402), a locking bolt (403), and a concave pressure block (404). The top block (401) is located above the topmost fixed connector (107), and the locking rod (402) is fixed to both sides of the bottom of the top block (401) and passes through the topmost fixed connector (107). The two horizontal cylinders (102) at the top of the two vertical parts of the rectangular frame (101) are provided with first locking holes (103), and the bottoms of the two locking rods (402) are respectively inserted into the two first locking holes (103); The J-shaped crossbar (202) has two horizontally distributed second locking holes (203). When the second locking hole (203) is aligned with the first locking hole (103), the locking rod (402) completely penetrates the second locking hole (203) to achieve the overall position locking of the inverted U-shaped side frame (201), the J-shaped crossbar (202), and the E-shaped base plate (205). The locking bolts (403) are distributed on the top of the top block (401) and pass through the top block (401), the fixed connector (107), the top straight slot type partition (301) and are threadedly connected to the concave pressure block (404). The concave pressure block (404) is sleeved on the bottom outside of the top straight slot type partition (301). The locking bolts (403) are tightened to lock the state of the separation component (3) and the adjustable limit component (2).
5. A portable transport device for emergency oxygen cylinders according to claim 4, characterized in that, The topmost fixed connector (107) has a through hole (108) for the locking rod (402) and the locking bolt (403) to pass through. The fixed connector (107) has an "Ω" shaped cross section when viewed from above. The fixed post (109) and the locking bolt (403) are distributed in the middle of the "Ω" shaped protrusion.
6. A portable transport device for emergency oxygen cylinders according to claim 2, characterized in that, The horizontal cylinders (102) on the two vertical parts of the rectangular frame (101) are vertically staggered and correspond one-to-one with the distribution positions of the J-shaped crossbars (202). The vertical parts of the rectangular frame (101) are formed with arc-shaped avoidance parts (104) to avoid the J-shaped crossbars (202).