A care bed frame with a telescopic positioning mechanism

Abstract

This utility model relates to a nursing bed frame with a telescopic positioning mechanism, comprising a bed frame body, the bed frame body including a pair of parallel horizontal bars and a vertical bar connecting the two horizontal bars, wherein the extension direction of the horizontal bars is defined as the length direction of the nursing bed, and the extension direction of the vertical bar is defined as the width direction of the nursing bed; a telescopic positioning unit movably mounted on the bed frame body, the telescopic positioning unit including an extension rod disposed outside the horizontal bars of the bed frame body, a telescopic component for changing the position between the extension rod and the bed frame body, and a positioning component for fixing the position between the extension rod and the bed frame body. The extension and retraction of the extension rod achieves the dimensional change of the bed frame body in the width direction. In this utility model, by adding an extension rod, a telescopic component, and a positioning component to the bed frame body, the extension rod can move closer to or further away from the bed frame body, thereby achieving the change in the length of the bed frame body in the width direction to meet the width requirements of different groups of people.

Description

Technical Field

[0001] This utility model relates to the field of nursing beds, and in particular to a nursing bed frame with a telescopic positioning mechanism. Background Technology

[0002] Nursing beds are hospital beds used by patients with limited mobility or other illnesses during hospitalization. Existing nursing beds have increasingly more functions. Although there are now beds that make it easier for patients to lean back or get up, the existing nursing beds have a fixed structure, which is not flexible for some special users. They can only facilitate movement and getting up, but cannot be used for training operations for patients who need rehabilitation training.

[0003] Patent CN213431153U proposes a telescopic nursing bed, which includes a front bed body and a rear bed body. The front bed body is connected to the rear bed body through a telescopic mechanism. The front bed body is equipped with a forearm training mechanism, and the rear bed body is equipped with a leg training mechanism.

[0004] The nursing bed described in the aforementioned patent achieves length-wise adjustment by moving the front and rear sections of the bed to accommodate different heights. However, in actual use, besides length-wise needs, there are also width-wise needs. For example, patients who have just undergone surgery may have difficulty turning over, and the nursing bed itself is designed to be relatively small in width, only slightly larger than an adult's width. In such cases, turning over on this narrow bed requires assistance from medical staff or family members, which is very inconvenient. Furthermore, turning over on this type of nursing bed is also quite difficult for obese patients. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a nursing bed frame with a telescopic positioning mechanism that can adjust the width of the nursing bed.

[0006] To solve the above-mentioned technical problems, the technical solution of this utility model is: a nursing bed frame with a telescopic positioning mechanism, the innovation of which is: including... A bed frame body, the bed frame body includes a pair of parallel horizontal bars and a vertical bar connected between the two horizontal bars, and the extension direction of the horizontal bars is defined as the length direction of the nursing bed, and the extension direction of the vertical bar is defined as the width direction of the nursing bed; A telescopic positioning unit is movably mounted on the main body of the bed frame. The telescopic positioning unit includes an extension rod located on the outside of the crossbar of the main body of the bed frame, a telescopic component for changing the position between the extension rod and the main body of the bed frame, and a positioning component for fixing the position between the extension rod and the main body of the bed frame. The dimensional change of the main body of the bed frame in the width direction is achieved by telescoping the extension rod.

[0007] Furthermore, the extension rod is disposed on the outside of the crossbar and extends along the extension direction of the crossbar, and the extension rod moves closer to or away from the crossbar under the action of the telescopic assembly, and at least two longitudinal rods are connected between the two crossbars; The telescopic assembly includes a main telescopic tube and a secondary telescopic tube disposed on the side of the extension rod near the crossbar, and telescopic grooves are respectively opened on the two longitudinal rods to allow the main telescopic tube and the secondary telescopic tube to be inserted into each other and move horizontally. The positioning component is mounted on the main telescopic tube and includes a positioning shaft, a positioning seat, and a drive rod. The positioning seat is mounted on the side of the main telescopic tube away from the extension rod. A mounting groove is provided on the positioning seat to accommodate the positioning shaft and allow it to move horizontally. The inner wall of the mounting groove is in contact with the outer wall of the positioning shaft. The positioning shaft is pushed by the drive rod to reciprocate between a first position and a second position. A through hole is also provided on the main telescopic tube to accommodate the extension of the positioning shaft, and a positioning hole is also provided on the longitudinal rod to accommodate the insertion of the positioning shaft. In the first position, the positioning shaft is placed in the positioning seat. At this time, the main telescopic tube and the longitudinal rod are relatively movable, and the main telescopic tube can slide horizontally in the telescopic groove of the longitudinal rod. In the second position, the positioning shaft extends out of the main telescopic tube and is embedded in the positioning hole of the longitudinal rod. At this time, the main telescopic tube and the longitudinal rod are relatively fixed.

[0008] Furthermore, the driving engagement between the positioning shaft and the drive rod is as follows: A transition swing plate is also provided between the positioning shaft and the drive rod. The transition swing plate is formed by connecting the first swing plate and the second swing plate in a V-shape. The connection between the first swing plate and the second swing plate is hinged to the positioning seat. One side of the first swing plate is hinged to the positioning shaft through the cooperation of the first pin. The first swing plate also has an oblong through hole for the first pin to pass through and move. One side of the second swing plate is hinged to one side of the drive rod through the cooperation of the second pin. The second swing plate also has a circular through hole for the second pin to pass through. The other side of the drive rod passes through the extension rod and is connected to a drive seat. The drive seat is mounted on the telescopic rod and has a through hole for the drive rod to pass through and move. A drive button that extends out of the drive seat is also connected to the side of the drive rod. A return spring is also provided between the drive seat and the drive rod. One side of the return spring abuts against the drive seat and the other side abuts against the drive button.

[0009] Furthermore, the longitudinal rod is also equipped with a limiting screw for unidirectionally limiting the position of the main telescopic tube.

[0010] Furthermore, a guide tube is also provided in the telescopic groove of the longitudinal rod. The guide tube and the longitudinal rod are connected by an insertion fitting, wherein the guide tube includes a guide tube body, and a through hole is opened on the crossbar to allow the guide tube body to pass through. One side of the guide tube body passes through the through hole on the crossbar and extends into the telescopic groove. The other side of the guide tube body has a guide tube limiting section, and the size of the guide tube limiting section is larger than the size of the through hole on the longitudinal rod. On both sides of the section of the guide tube body that extends into the telescopic groove, there are also fixing protrusions protruding from the guide tube body. At the same time, there are also fixing holes on the longitudinal rod to allow the fixing protrusions to be embedded one-to-one.

[0011] Furthermore, a U-shaped groove is also provided on the main body of the guide tube at the fixed protrusion, which surrounds the fixed protrusion, thereby forming an elastic plate that accommodates the installation of the fixed protrusion.

[0012] Furthermore, the side of the fixed protrusion away from the guide tube body is an inclined slope, and the inclined direction of the slope gradually moves away from the guide tube body from the guide tube body to the guide tube limiting section.

[0013] Furthermore, there are two extension rods, located on the outside of the two crossbars respectively.

[0014] The advantages of this utility model are as follows: In this utility model, by adding an extension rod, a telescopic component, and a positioning component to the bed frame body, the length of the bed frame body in the width direction can be changed by moving the extension rod closer to or further away from the bed frame body, so as to meet the width requirements of different groups of people for the nursing bed.

[0015] The telescopic assembly is designed with the main telescopic tube and the auxiliary telescopic tube working together to drive the horizontal movement of the extension rod, ensuring more stable movement of the extension rod. At the same time, it also strengthens the support of the extension rod after adjustment, so as to ensure that the extension rod can stably support the patient.

[0016] The positioning component is designed to fix the relative position of the extension rod and the longitudinal rod after the extension rod moves into place, through the cooperation of the positioning shaft, positioning seat and drive rod. This prevents relative displacement between the extension rod and the longitudinal rod.

[0017] The design of the limiting screw on the longitudinal bar is to limit the horizontal movement of the main telescopic tube within the longitudinal bar in one direction, thereby preventing the extension rod from getting too close to the crossbar.

[0018] The guide tube is designed to guide the main or auxiliary telescopic tube when it slides horizontally within the longitudinal rod, thus ensuring that the extension rod can retract and extend horizontally stably. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the nursing bed frame with telescopic positioning mechanism of this utility model.

[0020] Figure 2 This is a top view of the nursing bed frame with telescopic positioning mechanism of this utility model.

[0021] Figure 3 for Figure 2 AA sectional view.

[0022] Figure 4 This is a schematic diagram of the longitudinal bar in this utility model.

[0023] Figure 5 This is a schematic diagram of the telescopic positioning unit in this utility model.

[0024] Figure 6 for Figure 5 Enlarged schematic diagram of part B.

[0025] Figure 7 This is a schematic diagram of the telescopic component in this utility model.

[0026] Figure 8 This is a schematic diagram of the positioning component in this utility model. Detailed Implementation

[0027] To further illustrate the technical means and effects adopted by this utility model in order to achieve the intended utility model purpose, the following detailed description of the specific implementation methods, structure, features and effects of this utility model is provided in conjunction with the accompanying drawings and preferred embodiments.

[0028] like Figures 1-8 The nursing bed frame shown includes a telescopic positioning mechanism. A bed frame body includes a pair of parallel horizontal bars 1 and a vertical bar 2 connecting the two horizontal bars 1. The extension direction of the horizontal bars 1 is defined as the length direction of the nursing bed, and the extension direction of the vertical bar 2 is defined as the width direction of the nursing bed. The overall bed frame of the nursing bed in this utility model is composed of several bed frame bodies connected sequentially along the length direction.

[0029] A telescopic positioning unit that is movable and set on the main body of the bed frame, such as Figure 5As shown in the schematic diagram, the telescopic positioning unit includes an extension rod 3 located on the outside of the crossbar 1 of the bed frame body, a telescopic component for changing the position between the extension rod 3 and the bed frame body, and a positioning component for fixing the position between the extension rod 3 and the bed frame body. The extension and retraction of the extension rod 3 realizes the dimensional change of the bed frame body in the width direction.

[0030] Extension rod 3 is located on the outside of crossbar 1 and extends along the extension direction of crossbar 1. Extension rod 3 moves closer to or away from crossbar 1 under the action of telescopic components. Two longitudinal rods 2 are connected between the two crossbars 1. There are two extension rods 3, located on the outside of the two crossbars 1 respectively. The two extension rods 3 move independently under the cooperation of their respective telescopic components and positioning components, thereby moving closer to or away from crossbar 1, so as to realize the single-sided extension or double-sided simultaneous extension of the bed frame body in the width direction.

[0031] A limiting screw 21 is also installed on the longitudinal rod 2 to unidirectionally limit the position of the main telescopic tube 31. The limiting screw 21 on the longitudinal rod 2 is designed to unidirectionally limit the horizontal movement of the main telescopic tube 31 within the longitudinal rod 2, thereby preventing the extension rod 3 from getting too close to the crossbar.

[0032] The telescopic assembly includes a main telescopic tube 31 and a secondary telescopic tube 32 located on the side of the extension rod 3 near the crossbar 1. Telescopic grooves are respectively formed on the two longitudinal bars 2 to allow the main telescopic tube 31 and the secondary telescopic tube 32 to be inserted into and move horizontally. The design of the telescopic assembly utilizes the cooperation of the main telescopic tube 31 and the secondary telescopic tube 32 to drive the horizontal movement of the extension rod, ensuring more stable movement of the extension rod 3. It also provides enhanced support for the extension rod 3 after adjustment, ensuring stable support for the patient and preventing the patient from falling off the nursing bed due to unstable support from the extension rod 3.

[0033] The positioning assembly is mounted on the main telescopic tube 31 and includes a positioning shaft 34, a positioning seat 35, and a drive rod 33. The positioning seat 35 is installed on the side of the main telescopic tube 31 away from the extension rod 3, and the upper and lower sides of the positioning seat 35 are fixed inside the main telescopic tube 31 by screws. The positioning shaft 34 is a T-shaped structure formed by two cylindrical segments of different diameters connected together. A mounting groove is opened on the positioning seat 35 to accommodate the positioning shaft 34 and allow it to move horizontally. The inner wall of the mounting groove is in contact with the outer wall of the cylindrical segment with the larger diameter of the positioning shaft 34. The positioning shaft 34 is pushed by the drive rod 33 to reciprocate between the first position and the second position. A through hole is also opened on the main telescopic tube 31 to accommodate the extension of the positioning shaft 34. A positioning hole 22 is also opened on the longitudinal rod 2 to accommodate the insertion of the positioning shaft 34. There are several positioning holes 22, which are distributed sequentially on the longitudinal rod 2 along the long axis of the longitudinal rod 2. The diameter of the positioning hole 22 is consistent with the diameter of the cylindrical segment with the smaller diameter of the positioning shaft 34. The positioning component is designed so that, through the cooperation of the positioning shaft 34, the positioning seat 35 and the drive rod 33, the relative position of the extension rod 3 and the longitudinal rod 2 can be relatively fixed after the extension rod 3 moves into place, thus avoiding the phenomenon of relative displacement between the extension rod 3 and the longitudinal rod 2.

[0034] In the first position, the positioning shaft 34 is placed inside the positioning seat 35. At this time, the main telescopic tube 31 and the longitudinal rod 2 can move relative to each other. The main telescopic tube 31 can slide horizontally in the telescopic groove of the longitudinal rod 2 to achieve length adjustment in the width direction.

[0035] In the second position, the positioning shaft 34 extends out of the main telescopic tube 31 and is embedded in the positioning hole 22 of the longitudinal rod 2. At this time, the main telescopic tube 31 and the longitudinal rod 2 are relatively fixed.

[0036] Specifically, such as Figure 7 , Figure 8 As shown, the driving engagement between the positioning shaft 34 and the drive rod 33 is as follows: A transition swing plate is also provided between the positioning shaft 34 and the drive rod 33. The transition swing plate is formed by connecting the first swing plate 36 and the second swing plate 37 in a V-shape. The connection between the first swing plate 36 and the second swing plate 37 is hinged to the positioning seat 35 by a pin, so as to realize the swing of the transition swing plate relative to the positioning seat 35. One side of the first swing plate 36 is hinged to the positioning shaft 34 by a first pin. The first swing plate 36 also has an oblong through hole 361 for the first pin to pass through and move. The positioning shaft 34 has a circular through hole 341 for the first pin to pass through. One side of the second swing plate 37 is hinged to one side of the drive rod 33 by a second pin. The second swing plate 37 also has a circular through hole for the second pin to pass through.

[0037] The other side of the drive rod 33 passes through the extension rod 3 and is connected to a drive seat 331. The drive seat 331 is mounted on the extension rod 3 on both sides by screws. A through hole is provided in the drive seat 331 to allow the drive rod 33 to pass through and move. A drive button 332, extending out of the drive seat 331, is also connected to this side of the drive rod 33. The drive button 332 is directly fitted onto the outer wall of the drive rod 33. A return spring 333 is also provided between the drive seat 331 and the drive rod 33. One side of the return spring 33 rests against the drive seat 331, and the other side rests against the drive button 332. Through the design of the return spring 333, the drive rod 33 can be reset by the elastic action of the return spring 333 when no pressure is applied to the drive button 332.

[0038] A guide tube is also provided in the telescopic groove of the longitudinal rod 2. The guide tube is inserted into the longitudinal rod 2. The connection is as follows: the guide tube includes a guide tube body 38. A through hole is opened on the cross rod 1 to allow the guide tube body 38 to pass through. One side of the guide tube body 38 extends into the telescopic groove of the longitudinal rod 2 after passing through the through hole on the cross rod 1. The other side of the guide tube body 38 has a U-shaped guide tube limiting section 39, and the size of the guide tube limiting section 39 is larger than the size of the through hole on the longitudinal rod 2. On both sides of the section of the guide tube body 38 that extends into the telescopic groove, there are fixing protrusions 381 protruding from the guide tube body 38. At the same time, there are fixing holes 23 on the longitudinal rod 2 to accommodate the fixing protrusions 381. The design of the guide tube is to guide the main telescopic tube 31 or the auxiliary telescopic tube 32 when it slides horizontally in the longitudinal rod 2, and also to ensure that the extension rod 3 can stably telescopicate horizontally.

[0039] like Figure 6 As shown, a U-shaped groove 382 is also formed on the guide tube body 38 at the fixed protrusion 381, surrounding the fixed protrusion 381, thus forming an elastic plate 383 for accommodating the installation of the fixed protrusion 381. The design of the U-shaped groove 382 on the guide tube body 38 is to form an elastic plate 383 that is easy to deform, so that the fixed protrusion 381 can be pressed more smoothly later, so that the guide tube can be easily separated from the longitudinal rod 2. At the same time, it also facilitates the installation of the guide tube. The guide tube is generally made of metal plate, so the elastic plate 383 formed by the U-shaped groove 382 will have a certain degree of elasticity and deformation ability. This deformation ability is used to facilitate both the installation and removal of the guide tube.

[0040] The side of the fixed protrusion 381 away from the guide tube body 38 is an inclined surface, and the inclination direction of this inclined surface gradually moves away from the guide tube body 38 towards the guide tube limiting section 39. The inclined surface design of the side of the fixed protrusion 381 serves two purposes: firstly, it facilitates the smooth insertion of the guide tube into the longitudinal rod 2 during installation, preventing the installation of the guide tube from being affected by the presence of the fixed protrusion 381; secondly, after installation, the inclined surface acts as a one-way limiting force on the guide tube, preventing the guide tube from sliding out of the longitudinal rod 2 after installation, thus ensuring the relative fixation of the guide tube and the longitudinal rod 2.

[0041] In this embodiment, the crossbar 1, the longitudinal bar 2, the extension bar 3, the main telescopic tube 31, and the secondary telescopic tube 32 are all square tube structures.

[0042] Working principle: Under normal conditions, the positioning shaft 34 is in the second position, the return spring 333 is in its natural state, and the drive button 332 is outside the drive seat 331. When the width of the nursing bed needs to be adjusted, the drive button 332 is pressed manually, which drives the drive rod 33 to move horizontally towards the center of the longitudinal rod 2. The return spring 333 will be compressed, and the movement of the drive rod 33 will cause the transition swing plate to swing, and the transition swing plate will pull the positioning shaft 34 to move horizontally, so that the positioning shaft 34 moves from the second position to the first position. The positioning shaft 34 retracts into the positioning seat 35 and releases the fixation between the main telescopic tube 31 and the longitudinal rod 2. At this time, the extension rod 3 is pulled manually, so that the main telescopic tube 31 and the auxiliary telescopic tube 32 move horizontally within their respective longitudinal rods 2. At the same time, the drive button 332 is released, and the return spring 333 will drive the drive rod 33 to return to its original position away from the center of the longitudinal rod 2. When the extension rod 3 moves, the positioning shaft 34 will move from the first position to the second position. However, since there is no positioning hole 22 on the vertical rod 2 to match it, the relative position between the vertical rod 2 and the main telescopic tube 31 will not be fixed. At this time, the extension rod 3 can be pulled horizontally at will. The positioning shaft 34 has not completely moved to the first position, but the return spring 333 still applies a certain force to the drive rod 33. As the extension rod 3 moves, when the positioning shaft 34 slides to the next positioning hole 22 on the vertical rod 2, the positioning shaft 34 will be inserted into the positioning hole 22 under the action of the return spring 333. The positioning shaft 34 will completely move from the second position to the first position, realizing the relative fixation between the main telescopic tube 31 and the vertical rod 2, thus fixing the extension rod 3 and completing one stage of adjustment. If this width still does not meet the requirements, repeat the above steps or keep pressing the drive button 332 until the required width is achieved.

[0043] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A care bed frame with a telescopic positioning mechanism, characterized in that: include A bed frame body, the bed frame body includes a pair of parallel horizontal bars and a vertical bar connected between the two horizontal bars, and the extension direction of the horizontal bars is defined as the length direction of the nursing bed, and the extension direction of the vertical bar is defined as the width direction of the nursing bed; A telescopic positioning unit is movably mounted on the main body of the bed frame. The telescopic positioning unit includes an extension rod located on the outside of the crossbar of the main body of the bed frame, a telescopic component for changing the position between the extension rod and the main body of the bed frame, and a positioning component for fixing the position between the extension rod and the main body of the bed frame. The dimensional change of the main body of the bed frame in the width direction is achieved by telescoping the extension rod.

2. The care bed frame with a telescopic positioning mechanism according to claim 1, characterized in that: The extension rod is located on the outside of the crossbar and extends along the extension direction of the crossbar. The extension rod moves closer to or away from the crossbar under the action of the telescopic assembly. At least two longitudinal rods are connected between the two crossbars. The telescopic assembly includes a main telescopic tube and a secondary telescopic tube disposed on the side of the extension rod near the crossbar, and telescopic grooves are respectively opened on the two longitudinal rods to allow the main telescopic tube and the secondary telescopic tube to be inserted into each other and move horizontally. The positioning component is mounted on the main telescopic tube and includes a positioning shaft, a positioning seat, and a drive rod. The positioning seat is mounted on the side of the main telescopic tube away from the extension rod. A mounting groove is provided on the positioning seat to accommodate the positioning shaft and allow it to move horizontally. The inner wall of the mounting groove is in contact with the outer wall of the positioning shaft. The positioning shaft is pushed by the drive rod to reciprocate between a first position and a second position. A through hole is also provided on the main telescopic tube to accommodate the extension of the positioning shaft, and a positioning hole is also provided on the longitudinal rod to accommodate the insertion of the positioning shaft. In the first position, the positioning shaft is placed in the positioning seat. At this time, the main telescopic tube and the longitudinal rod are relatively movable, and the main telescopic tube can slide horizontally in the telescopic groove of the longitudinal rod. In the second position, the positioning shaft extends out of the main telescopic tube and is embedded in the positioning hole of the longitudinal rod. At this time, the main telescopic tube and the longitudinal rod are relatively fixed.

3. A care bed frame with a telescopic positioning mechanism according to claim 2, characterized in that: The driving engagement between the positioning shaft and the driving rod is as follows: A transition swing plate is also provided between the positioning shaft and the drive rod. The transition swing plate is formed by connecting the first swing plate and the second swing plate in a V-shape. The connection between the first swing plate and the second swing plate is hinged to the positioning seat. One side of the first swing plate is hinged to the positioning shaft through the cooperation of the first pin. The first swing plate also has an oblong through hole for the first pin to pass through and move. One side of the second swing plate is hinged to one side of the drive rod through the cooperation of the second pin. The second swing plate also has a circular through hole for the second pin to pass through. The other side of the drive rod passes through the extension rod and is connected to a drive seat. The drive seat is mounted on the telescopic rod and has a through hole for the drive rod to pass through and move. A drive button that extends out of the drive seat is also connected to the side of the drive rod. A return spring is also provided between the drive seat and the drive rod. One side of the return spring abuts against the drive seat and the other side abuts against the drive button.

4. The care bed frame with telescopic positioning mechanism according to claim 2, characterized in that: The longitudinal rod is also equipped with a limiting screw for unidirectionally limiting the position of the main telescopic tube.

5. The care bed frame with telescopic positioning mechanism according to claim 2, characterized in that: A guide tube is also provided in the telescopic groove of the longitudinal rod. The guide tube and the longitudinal rod are inserted and fitted together as follows: the guide tube includes a guide tube body, and a through hole is opened on the cross rod to allow the guide tube body to pass through. One side of the guide tube body passes through the through hole on the cross rod and extends into the telescopic groove. The other side of the guide tube body has a guide tube limiting section, and the size of the guide tube limiting section is larger than the size of the through hole on the longitudinal rod. On both sides of the section of the guide tube body that extends into the telescopic groove, there are fixing protrusions protruding from the guide tube body. At the same time, there are fixing holes on the longitudinal rod to allow the fixing protrusions to be embedded one-to-one.

6. A care bed frame with a telescopic positioning mechanism according to claim 5, characterized in that: The guide tube body also has a U-shaped groove at the fixed protrusion that surrounds the fixed protrusion, thus forming an elastic plate that accommodates the installation of the fixed protrusion.

7. The care bed frame with telescopic positioning mechanism according to claim 5, characterized in that: The side of the fixed protrusion away from the guide tube body is an inclined slope, and the slope direction gradually moves away from the guide tube body from the guide tube body to the guide tube limiting section.

8. The care bed frame with a telescopic positioning mechanism according to claim 1, characterized in that: There are two extension rods, located on the outside of the two crossbars respectively.

Images