Double-chain window opener

Abstract

The utility model discloses a double-chain window opener which comprises a window opener body, two chain assemblies and two window sash connecting blocks. The window opener body is installed on a lower frame of a window frame, and the two window sash connecting blocks are symmetrically installed on a lower frame of a window sash. One end of each chain assembly is arranged in the window opener body, and the other end of each chain assembly extends out of the window opener body from a corresponding chain outlet in the window opener body and is fixedly connected with the corresponding window sash connecting block. Chain cavities are symmetrically formed in the window opener body; the length of the chain extending out of the window opener body is synchronously adjusted by controlling the chain of the corresponding chain assembly to move in the corresponding chain cavity at the same time, then the chain pushes the corresponding window sash connecting block to move so as to drive the window sash to move, and opening and closing of the window are achieved. The window opener can solve the problem that an existing window opener is poor in stability and the like, is particularly suitable for opening and closing a window with a large width, and guarantees the stability of the window in the opening and closing process.

Description

Technical Field

[0001] The utility model is applied to a window opener, in particular to a double-chain window opener. Background Art

[0002] Most of the window openers currently on the market have complex internal structures. Once the window opener is damaged, it is necessary to replace the window opener intelligently, which increases the user's cost. As the chain window opener to control the opening and closing of windows has gradually become a popular trend, more and more people are using chain window openers. However, the existing chain window openers are generally single-chain window openers. For some larger windows, the single-chain window opener will be unstable during the window opening and closing process due to the insufficient support force of the single chain, and even cause the window sash to deform. Utility Model Content

[0003] In order to overcome the deficiencies of the prior art, the purpose of the present utility model is to provide a double-chain window opener, which can solve the problems of poor stability of the existing window opener during the window opening and closing process.

[0004] The purpose of the utility model is achieved by the following technical solutions:

[0005] A double-chain window opener, comprising: a window opener body, a first chain assembly, a second chain assembly, a first window sash connecting block and a second window sash connecting block; wherein the window opener body is mounted on the lower frame of the window frame, and the first window sash connecting block and the second window sash connecting block are symmetrically mounted on the lower frame of the window sash;

[0006] The window opener body is symmetrically provided with a first chain outlet and a second chain outlet; the first end of the first chain assembly is arranged inside the window opener body, the second end extends from the first chain outlet to the outside of the window opener body and is fixedly connected to the first window sash connecting block; the first end of the second chain assembly is arranged inside the window opener body, the second end extends from the second chain outlet to the outside of the window opener body and is fixedly connected to the second window sash connecting block;

[0007] The window opener body is symmetrically provided with a first chain cavity and a second chain cavity; the first chain assembly includes a first chain, and the first chain is arranged in the first chain cavity; the second chain assembly includes a second chain, and the second chain is arranged in the second chain cavity;

[0008] By simultaneously controlling the first chain to move in the first chain cavity and controlling the second chain to move in the second chain cavity, the length of the first chain and the length of the second chain extending outside the window opener body are synchronously adjusted, and then the first chain pushes the movement of the first sash connecting block and the second chain pushes the movement of the second sash connecting block to drive the movement of the window sash, thereby realizing opening and closing of the window.

[0009] Furthermore, the window opener body includes a base and a shell, and the base is fixedly connected to the shell to form an accommodating space for accommodating the first chain cavity and the second chain cavity; the base is symmetrically provided with a first chain groove and a second chain groove; the first end of the first chain groove is connected to the first chain outlet, the first end of the second chain groove is connected to the second chain outlet, and the second end of the first chain groove is spaced apart from the second end of the second chain groove; the first chain is used to move in the first chain groove to adjust the length of the chain extending to the outside of the window opener body to control the movement of the first window sash connecting block; the second chain is used to move in the second chain groove to adjust the length of the chain extending to the outside of the window opener body to control the movement of the second window sash connecting block.

[0010] Furthermore, the window opener body further comprises guide assemblies symmetrically arranged on the base, wherein one guide assembly is mounted on one end of the base provided with the first chain outlet, and is used to guide the first chain entering and exiting the first chain outlet; the other guide assembly is mounted on one end of the base provided with the second chain outlet, and is used to guide the second chain entering and exiting the second chain outlet;

[0011] The guide assembly includes a guide mounting groove, a guide column and a second spring; wherein the guide mounting groove is arranged on the base and the side plate of the guide mounting groove facing the corresponding chain outlet is provided with an opening; the second spring is installed in the guide mounting groove, and one end of the second spring is fixedly connected to the side plate of the guide mounting groove facing the corresponding chain outlet; the other end of the second spring is fixedly connected to one end of the guide column; the other end of the guide column faces the corresponding chain outlet and extends to the outside of the base, and is used to guide the chain entering and exiting the corresponding chain outlet.

[0012] Further, the first chain groove and the second chain groove each include an outlet guide groove, a plane annular guide groove and an inclined guide groove;

[0013] Wherein, the first outlet of the outlet guide groove of the first chain groove is communicated with the first chain outlet, and the second outlet is communicated with the first outlet of the plane annular guide groove of the first chain groove; the second outlet of the plane annular guide groove of the first chain groove is communicated with the first outlet of the inclined surface guide groove of the first chain groove; the second outlet of the inclined surface guide groove of the first chain groove is located at the interface between the second outlet of the outlet guide groove of the first chain groove and the first outlet of the plane annular guide groove of the first chain groove;

[0014] The first outlet of the outlet guide groove of the second chain groove is communicated with the second chain outlet, and the second outlet is communicated with the first outlet of the plane annular guide groove of the second chain groove; the second outlet of the plane annular guide groove of the second chain groove is communicated with the first outlet of the inclined surface guide groove of the second chain groove; the second outlet of the inclined surface guide groove of the second chain groove is located at the interface between the second outlet of the outlet guide groove of the second chain groove and the first outlet of the plane annular guide groove of the second chain groove;

[0015] The outlet guide groove is used to provide inlet and outlet guidance for the corresponding chain; the plane annular guide groove is used to provide the base plane guide support for the corresponding chain; the inclined guide groove is used to provide upward guide support for the corresponding chain so that the corresponding chain forms a double-layer spiral storage structure in the base;

[0016] A first annular guide handrail is provided in the area enclosed by the planar annular guide groove and the inclined guide groove of the first chain groove; a second annular guide handrail is provided in the area enclosed by the planar annular guide groove and the inclined guide groove of the second chain groove;

[0017] A first guide block is provided at the first end of the first chain, and a second guide block is provided at the first end of the second chain; guide bosses are provided at the bottom of the first guide block and the second guide block; the guide bosses of the first guide block clamp the first guide block to the first annular guide handrail; the guide bosses of the second guide block clamp the second guide block to the first annular guide handrail;

[0018] By controlling the first chain to move in the first chain groove and controlling the second chain to move in the second chain groove, the first guide block is synchronously driven to slide on the first annular guide handrail and the second guide block is synchronously driven to slide on the second annular guide handrail.

[0019] Furthermore, the window opener body further comprises symmetrically arranged safety lock blocks; the base is symmetrically provided with lock block mounting holes, and each lock block mounting hole is arranged on the base and corresponds to the corresponding annular guide handrail, and each safety lock block is installed in the corresponding lock block mounting hole; each safety lock block comprises a lock block bottom plate and a limit head arranged on the lock block bottom plate;

[0020] When the safety lock is opened, the limit head of each safety lock block extends into the base and contacts the inner side surface of the corresponding annular guide handrail to block the movement of the guide block of the corresponding chain, so that the maximum length of the corresponding chain extending outside the window opener body is limited to the first length;

[0021] When the safety lock is closed, the limit head of each safety lock block slides out of the base and separates from the corresponding annular guide handrail to release the movement of the guide block of the corresponding chain, so that the maximum length of the corresponding chain extending outside the window opener body is the second length;

[0022] The second length is greater than the first length, and the second length is less than the first chain length; the first chain length is the same as the second chain length.

[0023] Further, the window opener body further comprises a first bevel gear, a second bevel gear and a worm; wherein the first bevel gear is arranged at the second end of the first chain slot, and the inner side surface of the first chain is connected to the first sprocket gear at the bottom of the first bevel gear; the inner side surface of the first chain is the side surface away from the second chain;

[0024] The second bevel gear is disposed at the second end of the second chain groove, and the inner side surface of the second chain is connected to the second sprocket gear at the bottom of the second bevel gear; the inner side surface of the second chain is the side surface away from the first chain;

[0025] A worm support frame is provided between the second end of the first chain groove and the second end of the second chain groove, the bottom of the worm is fixed on the worm support frame, and the two sides of the worm are respectively connected with the top gear of the first bevel gear and the top gear of the second bevel gear; the first bevel gear and the second bevel gear are driven by the worm to rotate synchronously in opposite directions, and then the first chain is driven to move in the first chain groove by the first bevel gear and the second chain is driven to move in the second chain groove by the second bevel gear.

[0026] Furthermore, the window opener body also includes a handle assembly; the bottom end of the handle assembly is threadedly connected to the worm through a handle mounting hole provided on the window opener body, so that the worm is driven to rotate by rotating the handle assembly, thereby driving the first bevel gear and the second bevel gear to rotate synchronously in opposite directions.

[0027] Further, the worm comprises a supporting portion, a helical gear connecting portion and a handle connecting portion which are arranged sequentially from the bottom to the top;

[0028] Wherein, a support frame is provided inside the window opener body, and a worm mounting groove is provided on the support frame; the support portion of the worm is fixed in the mounting groove to support the worm between the first bevel gear and the second bevel gear;

[0029] Both sides of the helical gear connecting portion of the worm are respectively connected to the top gear of the first helical gear and the top gear of the second helical gear;

[0030] The handle connecting portion of the worm is threadedly connected to the bottom end of the handle assembly; the worm is driven to rotate by rotating the handle assembly, and then the first bevel gear and the second bevel gear are driven to rotate synchronously in opposite directions through the worm.

[0031] Furthermore, the window opener body further comprises a limit assembly, which is connected to the worm and is used to limit the worm to rotate in one direction, so as to limit the window sash to only close the window but not open the window;

[0032] The limit assembly includes a limit lock, a first spring and a lock core; wherein a pawl is provided at one end of the limit lock and a keyhole is provided at the other end; a lock core mounting hole is provided on the window opener body, the lock core is mounted on the window opener body through the lock core mounting hole, and the lock core convex column at the bottom of the lock core is located in the keyhole of the limit lock; the lock core is also fixedly connected to the limit lock through the first spring;

[0033] The lock core is rotated by a key to rotate a preset angle to compress the first spring, and then the limit lock is driven to move in the direction of the worm under the action of the first spring and the pawl of the limit lock contacts the worm to lock the worm to rotate in one direction. At this time, the window sash can only be closed but not opened.

[0034] The lock core is reset by a key to reset the first spring, and then the limit lock is driven to move away from the worm under the action of the first spring and the pawl of the limit lock is separated from the worm to release the worm.

[0035] Furthermore, the first chain assembly further comprises a chain connecting plate; one end of the chain connecting plate is fixedly connected to one end of the chain, and a rivet is provided at the bottom of the other end, the rivet is provided with a circular groove, and an open ring is clamped in the circular groove;

[0036] A mounting plate is provided on one side of the first window sash connecting block, and a connecting hole is provided on the mounting plate; the bottom end of the rivet is clamped in the connecting hole, and the chain connecting plate is fixedly connected to the first window sash connecting block through the open ring; the first window sash connecting block and the second window sash connecting block are symmetrically arranged.

[0037] Compared with the prior art, the beneficial effects of the present invention are:

[0038] The utility model provides a double-chain window opener, which realizes the opening and closing of the window sash by adopting a double-chain structure, and is more suitable for the opening and closing of a wide window type, so that the window is more stable during the opening and closing process. At the same time, the double chain adopted by the utility model moves synchronously inside the window opener body, which can ensure the stable movement of the window during the opening and closing process. The window opener housing provided by the utility model also has the characteristics of simple structure, smaller size, and convenient maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 An overall schematic diagram of a double-chain window opener provided by the utility model;

[0040] Figure 2 for Figure 1 Installation diagram of the double chain window opener and the window sash and window frame;

[0041] Figure 3 for Figure 1 Schematic diagram of the double chain window opener structure;

[0042] Figure 4 for Figure 3 An enlarged view of C in FIG.

[0043] Figure 5 A schematic diagram of the first bevel gear, the second bevel gear, the worm and the chain movement direction of the double-chain window opener when the window is opened;

[0044] Figure 6 for Figure 5 Schematic diagram of the movement direction of the first helical gear, the second helical gear, the worm and part of the chain of the double chain window opener

[0045] Figure 7 A schematic diagram of the first bevel gear, the second bevel gear, the worm and the chain movement direction of the double-chain window opener when the window is closed;

[0046] Figure 8 for Figure 1 A schematic diagram of the overall structure of the handle assembly;

[0047] Fig. 9 for Figure 8 Structural exploded view of the middle handle assembly;

[0048] Fig.10 for Fig. 9 A schematic diagram of the structure of the handlebar in FIG.

[0049] Fig.11 A schematic diagram of the structure of the double-chain window opener provided by the utility model when the worm is locked by a limit lock;

[0050] Fig.12 for Fig.11 A schematic diagram of the structure of the limit lock, the first spring, the lock core and the lock core protrusion 3442;

[0051] Fig.13 for Figure 3 Schematic diagram of the structure of the worm;

[0052] Fig.14 A schematic diagram of the installation structure of the first chain slot and the first chain of the double-chain window opener provided by the utility model;

[0053] Fig.15 for Fig.14 AA section diagram in;

[0054] Fig.16 for Fig.14 A schematic diagram of the double-layer spiral structure of the first chain and a schematic diagram of the structure of the first chain slot;

[0055] Fig.17 A schematic diagram of the structure of a double-chain window opener with a chain length of a first length when the safety lock block provided by the utility model is opened;

[0056] Fig.18 for Fig.17 A multi-angle schematic diagram of the middle;

[0057] Fig.19 A schematic diagram of the structure of the double-chain window opener when the safety lock block provided by the utility model is closed and the chain length is the second length and a schematic diagram of the vertical section at B;

[0058] Fig. 20 for Figure 3 An exploded view of the structure of the first chain assembly and the first window sash connecting block;

[0059] Fig.21 for Fig. 20 Schematic diagram of the installation of the first chain assembly and the first window sash connecting block.

[0060] In the figure: 1. Window frame;

[0061] 2. Window sashes;

[0062] 3. Window opener body;

[0063] 31. base; 311. outlet guide groove; 312. plane annular guide groove; 313. inclined guide groove;

[0064] 32. housing; 321. second screw;

[0065] 33. Handle assembly; 331. Handle; 3311. First fixing plate; 3312. Second fixing plate; 3313. Fixed shaft; 332. Handle head; 333. Knurled shaft; 334. Fixed shaft sleeve; 335. Connector; 336. Elastic cotter pin; 337. Set screw; 338. Mounting channel;

[0066] 341, limit lock; 342, first spring; 343, pressure plate; 344, lock core; 3442, lock core protrusion; 345, first screw; 3411, ratchet;

[0067] 35. first bevel gear; 351. first sprocket;

[0068] 36. second bevel gear; 361. second sprocket;

[0069] 37, worm; 371, support part; 372, bevel gear connection part; 373, lock gear connection part; 374, handle connection part; 375, support frame;

[0070] 38. Safety lock block; 381. Lock block bottom plate; 382. Limiting head;

[0071] 39. guide assembly; 391. guide column; 392. second spring;

[0072] 4. first chain assembly; 41. first chain; 411. chain connecting plate; 412. rivet; 413. circular groove; 414. open ring; 42. first guide block; 421. guide boss; 43. first annular guide handrail;

[0073] 5. second chain assembly; 51. second chain; 52. second guide block; 53. second annular guide handrail;

[0074] 6. First window sash connecting block; 61. Mounting plate; 62. Connecting hole;

[0075] 7. Second window sash connecting block. DETAILED DESCRIPTION

[0076] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0077] The utility model provides a preferred embodiment, such as Figure 1-Figure 21As shown, a double-chain window opener includes a window opener body 3, a first chain assembly 4, a second chain assembly 5, a first window sash connecting block 6 and a second window sash connecting block 7.

[0078] Specifically, Figure 1-Figure 2 As shown, the window opener body 3 is installed on the lower frame of the window frame 1, and the first sash connecting block 6 and the second sash connecting block 7 are symmetrically installed on the lower frame of the window sash 2. The first chain assembly 4 is fixedly connected to the window sash 2 through the first sash connecting block 6, and the second chain assembly 5 is fixedly connected to the window sash 2 through the second sash connecting block 7.

[0079] More specifically, the window opener body 3 is symmetrically provided with a first chain outlet and a second chain outlet. The first end of the first chain assembly 4 is arranged inside the window opener body 3, and the second end extends from the first chain outlet to the outside of the window opener body 3 and is fixedly connected to the first window sash connecting block 6. Similarly, the first end of the second chain assembly 5 is arranged inside the window opener body 3, and the second end extends from the second chain outlet to the outside of the window opener body 3 and is fixedly connected to the second window sash connecting block 7. When in use, the first chain assembly 4 and the second chain assembly 5 are controlled by the window opener body 3 to extend the chain length outside the window opener body 3 to drive the movement of the first window sash connecting block 6 and the second window sash connecting block 7, so as to adjust the distance between the window sash 2 and the window frame 1, and realize the window opening and closing.

[0080] Preferably, the structures of the first chain assembly 4 and the second chain assembly 5 in the utility model are symmetrically arranged, so that the movement of the first chain assembly 4 and the second chain assembly 5 can be synchronously controlled by the window opener body 3 to ensure that the window sash 2 is parallel during the opening and closing process, and the window sash 2 will not be deformed or even twisted due to the different chain lengths of the first chain assembly 4 and the second chain assembly 5 extending to the outside of the window opener body 3, thereby affecting the opening and closing of the window.

[0081] More preferably, the window opener body 3 is symmetrically provided with a first chain cavity and a second chain cavity. The first chain assembly 4 includes a first chain 41, and the second chain assembly 5 includes a second chain 51. The first chain 41 is arranged in the first chain cavity and moves in the first chain cavity. The second chain 51 is arranged in the second chain cavity and moves in the second chain cavity. That is, by simultaneously controlling the first chain 41 to move in the first chain cavity and controlling the second chain 51 to move in the second chain cavity, the lengths of the first chain 41 and the second chain 51 extending to the outside of the window opener body 3 are adjusted, and then the first chain 41 pushes the movement of the first sash connecting block 6 and the second chain 51 pushes the movement of the second sash connecting block 7, so as to drive the movement of the window sash 2, and realize the opening and closing of the window.

[0082] The utility model realizes the opening and closing of the window sash 2 by setting a double chain, which can more stably support the opening and closing of the window sash 2 and is particularly suitable for the opening of window sashes 2 with a larger width. For example, the double-chain window opener can be applied to windows with a width greater than 600 mm. On the contrary, for the single-chain window opener currently popular on the market, when the width of the window sash 2 is greater than a certain value, the window sash 2 cannot be smoothly opened and closed due to insufficient supporting force of the single chain.

[0083] Preferably, an installation groove is opened on the lower frame of the window frame 1, and the window opener body 3 is installed in the installation groove. The first window sash connecting block 6 and the second window sash connecting block 7 are both installed on the lower frame of the window sash 2, and the window opener body 3 is connected with the first window sash connecting block 6 and the second window sash connecting block 7 through the first chain assembly 4 and the second chain assembly 5 to realize the opening and closing of the window.

[0084] Preferably, if Figure 3 As shown, the window opener body 3 includes a base 31 and a shell 32, and the base 31 and the shell 32 are fixedly connected by a plurality of second screws 321 to form an accommodating space for accommodating the first chain cavity and the second chain cavity. More specifically, the base 31 is symmetrically provided with a first chain groove and a second chain groove, and the first end of the first chain groove is communicated with the first chain outlet, and the first end of the second chain groove is communicated with the second chain outlet. The first chain 41 moves in the first chain groove to adjust the chain length of the first chain 41 extending from the first chain outlet to the outside of the window opener body 3. Similarly, the second chain 51 moves in the second chain groove to adjust the chain length of the second chain 51 extending from the second chain outlet to the outside of the window opener body 3. By adjusting the chain length of the two chains outside the window opener body 3, the corresponding window sash connecting block can be pushed to move the window sash 2 away from the window frame 1 or to move it close to the window frame 1, so as to open or close the window.

[0085] More preferably, if Figure 13-Figure 15As shown, the first chain groove includes an outlet guide groove 311, a plane annular guide groove 312 and a bevel guide groove 313. Among them, the first outlet of the outlet guide groove 311 of the first chain groove is connected to the first chain outlet, and the second outlet is connected to the first outlet of the plane annular guide groove 312. The second outlet of the plane annular guide groove 312 is connected to the first outlet of the bevel guide groove 313, and the second outlet of the bevel guide groove 313 is located at the interface between the second outlet of the outlet guide groove 311 and the first outlet of the plane annular guide groove 312. The utility model can form a double-layer spiral storage structure of the first chain 41 in the base 31 through the plane annular guide groove 312 and the bevel guide groove 313, so as to maximize the space utilization inside the double-chain window opener while ensuring the chain length, effectively control the overall outer diameter of the window opener, reduce the outer diameter of the product, and thus be suitable for more window types.

[0086] The planar annular guide groove 312 in this embodiment is used to provide a guide support for the first chain 41 to move smoothly in the base 31. The inclined guide groove 313 is used to provide a guide support for the first chain 41 to move upward in the base 31. Fig.15 The double-layer spiral structure formed by the first chain 41 shown can realize a smaller size of the window opener body 3 and a longer chain, and can be applicable to various types of windows.

[0087] The outlet guide groove 311 is used to guide the first chain 41 entering and exiting the first chain outlet to prevent the chain from getting tangled and being unable to enter and exit smoothly.

[0088] Preferably, if Fig.13 and Figure 5 As shown, a first annular guide handrail 43 is provided in the area enclosed by the plane annular guide groove 312 and the inclined guide groove 313. A first guide block 42 is provided at the first end of the first chain 41, and a guide boss 421 is provided at the bottom of the first guide block 42. The first guide block 42 is clamped on the first annular guide handrail 43 by the guide boss 421, and the first guide block 42 slides on the first annular guide handrail 43. That is, when the first chain 41 moves in the first chain groove, the first guide block 42 is driven to slide on the first annular guide handrail 43 by the first chain 41. By providing the first annular guide handrail 43 to guide the direction in which the first chain 41 slides in the base 31, the direction in which the first chain 41 slides in the first chain groove can be guaranteed, and the first chain 41 can be prevented from slipping out of the first chain groove and causing the first chain 41 to be knotted.

[0089] Similarly, the second chain groove is symmetrically arranged with the first chain groove, and also includes an outlet guide groove 311, a plane annular guide groove 312 and an inclined surface guide groove 313. Among them, the first outlet of the outlet guide groove 311 of the second chain groove is connected with the second chain outlet. Similarly, a second annular guide handrail 53 is provided in the area enclosed by the plane annular guide groove 312 and the inclined surface guide groove 313 of the second chain groove. A second guide block 52 is provided at the first end of the second chain 51. A guide boss 421 is also provided at the bottom of the second guide block 52, and the second guide block 52 is clamped to the second annular guide handrail 53 by the guide boss 421, as shown in FIG. Figure 5 When the second chain 51 is controlled to move in the second chain groove, the second guide block 52 is driven to slide on the second annular guide handrail 53 .

[0090] Preferably, if Figure 3 As shown, the window opener body 3 further includes a first bevel gear 35, a second bevel gear 36 and a worm 37. The first bevel gear 35 is disposed at the second end of the first chain groove, and the inner side surface of the first chain 41 is gear-connected with the first sprocket 351 at the bottom of the first bevel gear 35. The inner side surface of the first chain 41 in this embodiment is a side surface away from the second chain 51, such as the inner side surface of the annular structure formed by the first chain 41 in this embodiment.

[0091] Similarly, the second bevel gear 36 is disposed at the second end of the second chain groove, and the inner side surface of the second chain 51 is gear-connected with the second sprocket 361 at the bottom of the second bevel gear 36; the inner side surface of the second chain 51 is the side surface away from the first chain 41. Specifically, Figure 3 As shown, the first chain 41 passes through the right side of the first bevel gear 35, and the second chain 51 passes through the left side of the second bevel gear 36. The first chain 41 is moved by the rotation of the first bevel gear 35, and the second chain 51 is moved by the rotation of the second bevel gear 36.

[0092] A support frame 375 is provided between the first chain groove and the second chain groove, the bottom of the worm 37 is fixed on the support frame 375, and both sides of the worm 37 are respectively connected to the top gear of the first bevel gear 35 and the top gear of the second bevel gear 36. Specifically, a mounting groove is provided on the support frame 375, and the bottom of the worm 37 is fixed in the mounting groove to support the worm 37 between the first bevel gear 35 and the second bevel gear 36.

[0093] The worm gear 37 drives the first bevel gear 35 and the second bevel gear 36 to rotate synchronously in opposite directions, and then the first bevel gear 35 drives the first chain 41 to move in the first chain groove, and the second bevel gear 36 drives the second chain 51 to move in the second chain groove, and at the same time drives the first guide block 42 to slide on the first annular guide handrail 43 and drives the second guide block 52 to slide on the second annular guide handrail 53.

[0094] At the same time, the first chain 41 drives the first guide block 42 to slide on the first annular guide handrail 43, and the second chain 51 drives the second guide block 52 to slide on the second annular guide handrail 53. By setting corresponding guide blocks and annular guide handrails, it can be ensured that the direction of the corresponding chain will not deviate during the movement, thereby avoiding chain knotting.

[0095] Specifically, Figure 1 , Figure 2 as well as Figure 3 For the double-chain window opener shown, when the window needs to be opened, the worm 37 is rotated counterclockwise, at this time, the first bevel gear 35 rotates counterclockwise under the action of the worm 37, and the second bevel gear 36 rotates clockwise under the action of the worm 37, and the first chain 41 moves toward the outside of the window opener body 3 driven by the first bevel gear 35, and the second chain 51 moves toward the outside of the window opener body 3 driven by the second bevel gear 36, and then the window sash 2 is moved away from the window frame 1 through the first window sash connecting block 6 and the second window sash connecting block 7.

[0096] On the contrary, when the window needs to be closed, the worm 37 is rotated clockwise, at which time the first bevel gear 35 rotates clockwise under the action of the worm 37, and the second bevel gear 36 rotates counterclockwise under the action of the worm 37, the first chain 41 moves toward the inside of the window opener body 3 under the drive of the first bevel gear 35, and the second chain 51 moves toward the inside of the window opener body 3 under the drive of the second bevel gear 36, and then the window sash 2 is moved toward the direction close to the window frame 1 through the first sash connecting block 6 and the second sash connecting block 7. In addition, the relationship between the rotation direction of the worm 37 and the opening and closing of the window is specifically set according to actual needs. For example, when the chain outlet is set on the right side of the base 31 in this embodiment, when the worm 37 rotates counterclockwise, the window is opened; when the worm 37 rotates clockwise, the window is closed. On the contrary, when the chain outlet is set on the left side of the base 31, at this time, when the worm 37 rotates counterclockwise, the window is closed; when the worm 37 rotates clockwise, the window is closed. That is, the utility model does not restrict the opening and closing direction of the window and the rotation direction of the worm 37. The specific setting is based on the actual situation. It only needs to ensure that when the worm 37 rotates, the first bevel gear 35 and the second bevel gear 36 rotate synchronously in opposite directions to ensure that the first chain 41 and the second chain 51 move synchronously toward the inside of the window opener body 3 or toward the outside of the window opener body 3.

[0097] Preferably, if Figure 3 As shown, the window opener body 3 is also provided with a handle assembly 33. The housing 32 is provided with a handle mounting hole. The bottom end of the handle assembly 33 is threadedly connected to the worm 37 inside the window opener body 3 through the handle mounting hole. In this way, the worm 37 can be driven to rotate by rotating the handle assembly 33, thereby driving the first bevel gear 35 and the second bevel gear 36 to rotate synchronously in opposite directions. Specifically, as shown in FIG. Figure 5 and Figure 6 As shown, by rotating the handle assembly 33 counterclockwise, the worm 37 can be driven to rotate counterclockwise. At this time, the first bevel gear 35 rotates counterclockwise under the action of the worm 37, and the second bevel gear 36 rotates clockwise under the action of the worm 37; the first chain 41 and the second chain 51 both move toward the outside of the window opener body 3, increasing the chain length of the first chain 41 located outside the window opener body 3 and increasing the chain length of the second chain 51 located outside the window opener body 3, thereby driving the first window sash connecting block 6 and the second window sash connecting block 7 to move away from the window frame 1 at the same time, that is, pushing the window sash 2 away from the window frame 1 to achieve window opening.

[0098] On the contrary, Figure 7As shown, by rotating the handle assembly 33 clockwise, the worm 37 can be driven to rotate clockwise. At this time, the first bevel gear 35 rotates clockwise under the action of the worm 37, and the second bevel gear 36 rotates counterclockwise under the action of the worm 37; the first chain 41 and the second chain 51 both move toward the inside of the window opener body 3 to shorten the chain length of the first chain 41 and the second chain 51 located outside the window opener body 3, so as to drive the first window sash connecting block 6 and the second window sash connecting block 7 to move toward the window frame 1, that is, to pull the window sash 2 toward the window frame 1 to achieve window closing.

[0099] Preferably, if Figure 8-Figure 10 As shown, the handle assembly 33 includes a handle 331, a handle head 332, a knurled shaft 333, a fixed sleeve 334, a connector 335, an elastic cotter pin 336 and a set screw 337. The handle 331 includes a first fixed plate 3311, a second fixed plate 3312 and a fixed shaft 3313. The fixed shaft 3313 is arranged at one end of the first fixed plate 3311 and one end of the second fixed plate 3312, so that the first fixed plate 3311 and the second fixed plate 3312 are arranged parallel and symmetrically. The fixed sleeve 334 is sleeved on the outside of the fixed shaft 3313, one end of the knurled shaft 333 is inserted into the inside of the fixed sleeve 334, and the other end is inserted into the inside of the handle head 332. The handle head 332 is driven to rotate 360 ​​degrees by the rotation of the knurled shaft 333 in the fixed sleeve 334.

[0100] The other end of the first fixing plate 3311, the other end of the second fixing plate 3312, and one end of the connector 335 are all provided with mounting holes. The elastic cotter pin 336 is sequentially inserted into the mounting hole of the first fixing plate 3311, the mounting hole of the connector 335, and the mounting hole of the second fixing plate 3312 to place the connector 335 between the first fixing plate 3311 and the second fixing plate 3312.

[0101] A mounting channel 338 with an internal thread is provided in the middle of the connector 335. One end of the worm 37 is installed in the mounting channel 338 and is threadedly connected to the connector 335. The worm 37 is then driven to rotate by rotating the handle assembly 33. A set screw 337 is also installed in the middle of the other end of the connector 335. The worm 37 is fixed by the set screw 337. In this way, when the handle assembly 33 is rotated clockwise or counterclockwise, the connector 335 drives the worm 37 to rotate clockwise or counterclockwise, thereby driving the first bevel gear 35 and the second bevel gear 36 to rotate synchronously in opposite directions to drive the window to be closed or opened.

[0102] In addition, the utility model connects the handle 331 and the connector 335 through an elastic cotter pin 336, so that the user can better operate and store the handle 331, making the window opener more beautiful.

[0103] More preferably, the window opener body 3 further includes a limit assembly. The limit assembly is connected to the worm 37 and is used to limit the worm 37 to rotate in one direction, so as to limit the window sash 2 to only close the window but not open the window. The utility model is used to limit the opening of the window by setting the limit assembly. Specifically, Figure 2 , Fig.11 and Fig.12 As shown, the limit assembly includes a limit lock 341, a first spring 342, a pressure plate 343 and a lock core 344. The pressure plate 343 is fixed in the base 31 by a first screw 345, and is fixedly connected to the limit lock 341, and is used to support the limit lock 341. A pawl 3411 is provided at one end of the limit lock 341, and a keyhole is provided at the other end. A lock core mounting hole is provided on the housing 32 of the window opener body 3, and the lock core 344 is installed on the housing 32 through the lock core mounting hole, and the lock core protrusion 3442 at the bottom of the lock core 344 is located in the keyhole of the limit lock 341. The lock core 344 is also fixedly connected to the limit lock 341 through the first spring 342; the lock core 344 is rotated by the key to rotate the preset angle to compress the first spring 342, and then the limit lock 341 is driven to move in the direction of the worm 37 under the action of the first spring 342 and the pawl 3411 of the limit lock 341 contacts the worm 37 to lock the worm 37 to only rotate in one direction. At this time, the window sash 2 can only close the window, not open the window. In this way, the opening angle of the window is limited.

[0104] The lock cylinder 344 is reset by a key to reset the first spring 342 , and then the limit lock 341 is driven by the first spring 342 to move away from the worm 37 and the pawl 3411 of the limit lock 341 is separated from the worm 37 to release the worm 37 .

[0105] That is, if Fig.11 As shown, for the double-chain window opener provided in this embodiment, when the worm 37 rotates counterclockwise, the window is open. Therefore, in order to avoid the window opening due to misoperation, the limit lock 341 is arranged on the left side of the worm 37 to limit the counterclockwise direction of the worm 37. In this way, when the limit lock 341 is opened, the worm 37 can only rotate clockwise, and the window sash 2 can only move in the direction of closing the window, which can avoid the problem of pets or children misoperating and causing the window to open too large an angle and cause danger.

[0106] Preferably, more specifically, the limit lock 341 includes a first component, a second component and a third component, and the first component is vertically arranged with the second component, and the second component is vertically arranged with the third component; the first end of the third component is provided with a pawl 3411, the second end is connected with the first end of the second component, the second end of the second component is connected with the first end of the first component, and the second end of the first component is provided with a keyhole; the middle of the third component is also provided with a spring installation groove, the first spring 342 is arranged in the spring installation groove, and one end of the first spring 342 is fixedly connected to the third component, and the other end is fixedly connected to the lock core 344. More preferably, the limit lock 341 is formed by bending a stainless steel plate, that is, the first component, the second component and the third component are an integrated structure.

[0107] More specifically, Fig.13 As shown, the worm 37 includes a support portion 371, a bevel gear connection portion 372, a lock gear connection portion 373 and a handle connection portion 374 which are arranged sequentially from the bottom to the top.

[0108] The supporting portion 371 of the worm 37 is fixed in the mounting groove of the supporting frame 375 to support the worm 37 between the first bevel gear 35 and the second bevel gear 36 .

[0109] Both sides of the helical gear connecting portion 372 of the worm 37 are connected to the top gear of the first helical gear 35 and the top gear of the second helical gear 36 respectively.

[0110] The handle connecting portion 374 of the worm 37 is threadedly connected to the bottom end of the handle assembly 33. The worm 37 is driven to rotate by rotating the handle assembly 33, and then the first bevel gear 35 and the second bevel gear 36 are driven to rotate synchronously in opposite directions through the worm 37.

[0111] The lock gear connecting portion 373 of the worm 37 is connected to the pawl 3411 of the limit lock 341. The pawl 3411 of the limit lock 341 is in contact with the lock gear connecting portion 373 of the worm 37 to lock the worm 37 to rotate in only one direction.

[0112] Further, if Fig.17 and Fig.18 As shown, the window opener body 3 also includes a symmetrically arranged safety lock block 38. The base 31 is symmetrically provided with lock block mounting holes, and each lock block mounting hole is within the area of ​​the base 31 enclosed by the corresponding annular guide handrail. Each safety lock block 38 is mounted on the base 31 through the corresponding lock block mounting hole. More specifically, the safety lock block 38 includes a lock block bottom plate 381 and a limit head 382 provided on the lock block bottom plate 381. When the safety lock block 38 is opened, the limit head 382 of the safety lock block 38 is extended into the base 31 through the lock buckle mounting hole and is located on the inner side of the corresponding annular guide handrail, as shown in FIG. Fig.18As shown, the limit head 382 of the safety lock block 38 blocks the movement of the first guide block 42 of the first chain 41, so that the maximum length of the corresponding chain extending outside the window opener body 3 is limited to the first length.

[0113] When the safety lock block 38 is closed, the limit head 382 of the safety lock block 38 is flipped to separate it from the corresponding annular guide handrail. Fig.19 As shown, the first guide block 42 of the first chain 41 is not blocked by the limit head 382 of the safety lock block 38, and can continue to move until the length of the chain extending to the outside reaches the maximum length, that is, the second length. Among them, the second length is greater than the first length, and the second length is less than the corresponding chain length. That is, in this embodiment, by setting the safety lock block 38, the safety lock block 38 blocks the guide block on the corresponding annular guide handrail to block the movement of the corresponding chain, so that when the safety lock block 38 is opened, the maximum length of the chain extending from the window opener body 3 to the outside is fixed, which can avoid the problem of the window opening angle being too large. Of course, when the safety lock block 38 is closed, the maximum length of the chain extending from the window opener body 3 to the outside can reach the designed maximum length, that is, the opening angle of the window sash 2 reaches the maximum.

[0114] Preferably, if Figure 3 As shown, the window opener body 3 includes symmetrically arranged guide assemblies 39. One of the guide assemblies 39 is installed at one end of the base 31 provided with a first chain outlet, and guides the first chain 41 entering and exiting the first chain outlet. Another guide assembly 39 is installed at one end of the base 31 provided with a second chain outlet, and guides the second chain 51 entering and exiting the second chain outlet.

[0115] Specifically, the guide assembly 39 includes a guide installation slot 391, a guide column 392 and a second spring 393. The guide installation slot 391 is provided on the base 31 and the guide installation slot 391 is provided with an opening toward the side plate corresponding to the chain outlet.

[0116] The second spring 393 is installed in the guide installation groove 391, and one end of the second spring 393 is fixedly connected to the side plate of the guide installation groove 391 facing the corresponding chain outlet.

[0117] The other end of the second spring 393 is fixedly connected to one end of the guide column. The other end of the guide column 392 faces the corresponding chain outlet and extends to the outside of the base 31, which is used to guide the chain entering and exiting the corresponding chain outlet to avoid the corresponding chain from tangling and ensure smooth movement of the corresponding chain.

[0118] More specifically, a partition plate 9 is provided between the guide column 392 of each guide assembly 39 and the corresponding chain in the corresponding outlet guide groove 311. The guide column 392 is isolated from the corresponding chain by the partition plate 9 to prevent the corresponding chain from rubbing against the corresponding guide assembly 39.

[0119] Preferably, if Fig. 20 and Fig.21 As shown, the first chain assembly 4 also includes a chain connecting plate 411. For the first chain assembly 4, one end of the chain connecting plate 411 is fixedly connected to one end of the first chain 41, and a rivet 412 is provided at the bottom of the other end. A circular groove 413 is provided on the rivet 412. An open ring 414 is clamped in the circular groove 413.

[0120] A mounting plate 61 is provided on one side of the first window sash connecting block 6, and a connecting hole 62 is provided on the mounting plate 61. The bottom end of the rivet 412 is clamped in the connecting hole 62, and the chain connecting plate 411 is fixedly connected to the first window sash connecting block 6 through the open ring 414. The open ring 414 is first installed in the circular groove 413, and then the rivet 412 of the chain connecting plate 411 is pressed down toward the connecting hole 62 of the window sash connecting block, so that the chain connecting plate 411 is fixedly connected to the first window sash connecting block 6 and fixed through the open ring 414. This installation method is simple and convenient, and easy to operate. Similarly, the second chain assembly 5 is symmetrically arranged with the first chain assembly 4.

[0121] The above-mentioned implementation modes are only preferred implementation modes of the present invention, and cannot be used to limit the protection scope of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A double-chain window opener, characterized in that: The double-chain window opener comprises: a window opener body, a first chain assembly, a second chain assembly, a first window sash connecting block and a second window sash connecting block; wherein the window opener body is mounted on the lower frame of the window frame, and the first window sash connecting block and the second window sash connecting block are symmetrically mounted on the lower frame of the window sash respectively; The window opener body is symmetrically provided with a first chain outlet and a second chain outlet; the first end of the first chain assembly is arranged inside the window opener body, the second end extends from the first chain outlet to the outside of the window opener body and is fixedly connected to the first window sash connecting block; the first end of the second chain assembly is arranged inside the window opener body, the second end extends from the second chain outlet to the outside of the window opener body and is fixedly connected to the second window sash connecting block; The window opener body is symmetrically provided with a first chain cavity and a second chain cavity; the first chain assembly includes a first chain, and the first chain is arranged in the first chain cavity; the second chain assembly includes a second chain, and the second chain is arranged in the second chain cavity; By simultaneously controlling the first chain to move in the first chain cavity and controlling the second chain to move in the second chain cavity, the length of the first chain and the length of the second chain extending outside the window opener body are synchronously adjusted, and then the first chain pushes the movement of the first sash connecting block and the second chain pushes the movement of the second sash connecting block to drive the movement of the window sash, thereby realizing opening and closing of the window.

2. The double-chain window opener according to claim 1, characterized in that: The window opener body comprises a base and a shell, and the base is fixedly connected to the shell to form an accommodating space for accommodating the first chain cavity and the second chain cavity; A first chain groove and a second chain groove are symmetrically provided in the base; a first end of the first chain groove is connected to the first chain outlet, a first end of the second chain groove is connected to the second chain outlet, and a second end of the first chain groove is spaced apart from a second end of the second chain groove; the first chain is used to move in the first chain groove to adjust the length of the chain extending to the outside of the window opener body to control the movement of the first window sash connecting block; the second chain is used to move in the second chain groove to adjust the length of the chain extending to the outside of the window opener body to control the movement of the second window sash connecting block.

3. The double-chain window opener according to claim 2, characterized in that: The window opener body further comprises guide assemblies symmetrically arranged on the base, wherein one guide assembly is mounted on one end of the base provided with the first chain outlet, and is used to guide the first chain entering and exiting the first chain outlet; the other guide assembly is mounted on one end of the base provided with the second chain outlet, and is used to guide the second chain entering and exiting the second chain outlet; The guide assembly includes a guide mounting groove, a guide column and a second spring; wherein the guide mounting groove is arranged on the base and the side plate of the guide mounting groove facing the corresponding chain outlet is provided with an opening; the second spring is installed in the guide mounting groove, and one end of the second spring is fixedly connected to the side plate of the guide mounting groove facing the corresponding chain outlet; the other end of the second spring is fixedly connected to one end of the guide column; the other end of the guide column faces the corresponding chain outlet and extends to the outside of the base, and is used to guide the chain entering and exiting the corresponding chain outlet.

4. The double-chain window opener according to claim 2, characterized in that: The first chain groove and the second chain groove each include an outlet guide groove, a plane annular guide groove and an inclined guide groove; Wherein, the first outlet of the outlet guide groove of the first chain groove is communicated with the first chain outlet, and the second outlet is communicated with the first outlet of the plane annular guide groove of the first chain groove; the second outlet of the plane annular guide groove of the first chain groove is communicated with the first outlet of the inclined surface guide groove of the first chain groove; the second outlet of the inclined surface guide groove of the first chain groove is located at the interface between the second outlet of the outlet guide groove of the first chain groove and the first outlet of the plane annular guide groove of the first chain groove; The first outlet of the outlet guide groove of the second chain groove is communicated with the second chain outlet, and the second outlet is communicated with the first outlet of the plane annular guide groove of the second chain groove; the second outlet of the plane annular guide groove of the second chain groove is communicated with the first outlet of the inclined surface guide groove of the second chain groove; the second outlet of the inclined surface guide groove of the second chain groove is located at the interface between the second outlet of the outlet guide groove of the second chain groove and the first outlet of the plane annular guide groove of the second chain groove; The outlet guide groove is used to provide inlet and outlet guidance for the corresponding chain; the plane annular guide groove is used to provide the base plane guide support for the corresponding chain; the inclined guide groove is used to provide upward guide support for the corresponding chain so that the corresponding chain forms a double-layer spiral storage structure in the base; A first annular guide handrail is provided in the area enclosed by the planar annular guide groove and the inclined guide groove of the first chain groove; a second annular guide handrail is provided in the area enclosed by the planar annular guide groove and the inclined guide groove of the second chain groove; A first guide block is provided at the first end of the first chain, and a second guide block is provided at the first end of the second chain; guide bosses are provided at the bottom of the first guide block and the second guide block; the guide bosses of the first guide block clamp the first guide block to the first annular guide handrail; the guide bosses of the second guide block clamp the second guide block to the first annular guide handrail; By controlling the first chain to move in the first chain groove and controlling the second chain to move in the second chain groove, the first guide block is synchronously driven to slide on the first annular guide handrail and the second guide block is synchronously driven to slide on the second annular guide handrail.

5. The double-chain window opener according to claim 4, characterized in that: The window opener body also includes symmetrically arranged safety lock blocks; the base is symmetrically provided with lock block mounting holes, and each lock block mounting hole is arranged on the base and corresponds to the corresponding annular guide handrail, and each safety lock block is installed in the corresponding lock block mounting hole; each safety lock block includes a lock block bottom plate and a limit head arranged on the lock block bottom plate; When the safety lock is opened, the limit head of each safety lock block extends into the base and contacts the inner side surface of the corresponding annular guide handrail to block the movement of the guide block of the corresponding chain, so that the maximum length of the corresponding chain extending outside the window opener body is limited to the first length; When the safety lock is closed, the limit head of each safety lock block slides out of the base and separates from the corresponding annular guide handrail to release the movement of the guide block of the corresponding chain, so that the maximum length of the corresponding chain extending outside the window opener body is the second length; The second length is greater than the first length, and the second length is less than the first chain length; the first chain length is the same as the second chain length.

6. The double-chain window opener according to claim 1, characterized in that: The window opener body further comprises a first bevel gear, a second bevel gear and a worm; wherein the first bevel gear is arranged at the second end of the first chain slot, and the inner side surface of the first chain is connected to the first sprocket gear at the bottom of the first bevel gear; the inner side surface of the first chain is the side surface away from the second chain; The second bevel gear is disposed at the second end of the second chain groove, and the inner side surface of the second chain is connected to the second sprocket gear at the bottom of the second bevel gear; the inner side surface of the second chain is the side surface away from the first chain; A worm support frame is provided between the second end of the first chain groove and the second end of the second chain groove, the bottom of the worm is fixed on the worm support frame, and the two sides of the worm are respectively connected with the top gear of the first bevel gear and the top gear of the second bevel gear; the first bevel gear and the second bevel gear are driven by the worm to rotate synchronously in opposite directions, and then the first chain is driven to move in the first chain groove by the first bevel gear and the second chain is driven to move in the second chain groove by the second bevel gear.

7. The double-chain window opener according to claim 6, characterized in that: The window opener body also includes a handle assembly; the bottom end of the handle assembly is threadedly connected to the worm through a handle mounting hole provided on the window opener body, so that the worm is driven to rotate by rotating the handle assembly, thereby driving the first bevel gear and the second bevel gear to rotate synchronously in opposite directions.

8. The double-chain window opener according to claim 7, characterized in that: The worm comprises a supporting portion, a helical gear connecting portion and a handle connecting portion which are arranged sequentially from the bottom to the top; Wherein, a support frame is provided inside the window opener body, and a worm mounting groove is provided on the support frame; the support portion of the worm is fixed in the mounting groove to support the worm between the first bevel gear and the second bevel gear; Both sides of the helical gear connecting portion of the worm are respectively connected to the top gear of the first helical gear and the top gear of the second helical gear; The handle connecting portion of the worm is threadedly connected to the bottom end of the handle assembly; the worm is driven to rotate by rotating the handle assembly, and then the first bevel gear and the second bevel gear are driven to rotate synchronously in opposite directions through the worm.

9. The double-chain window opener according to claim 6, characterized in that: The window opener body also includes a limit assembly, which is connected to the worm and is used to limit the worm to rotate in one direction, so as to limit the window sash to only close the window but not open the window; The limit assembly includes a limit lock, a first spring and a lock core; wherein a pawl is provided at one end of the limit lock and a keyhole is provided at the other end; a lock core mounting hole is provided on the window opener body, the lock core is mounted on the window opener body through the lock core mounting hole, and the lock core convex column at the bottom of the lock core is located in the keyhole of the limit lock; the lock core is also fixedly connected to the limit lock through the first spring; The lock core is rotated by a key to rotate a preset angle to compress the first spring, and then the limit lock is driven to move in the direction of the worm under the action of the first spring and the pawl of the limit lock contacts the worm to lock the worm to rotate in one direction. At this time, the window sash can only be closed but not opened. The lock core is reset by a key to reset the first spring, and then the limit lock is driven to move away from the worm under the action of the first spring and the pawl of the limit lock is separated from the worm to release the worm.

10. The double-chain window opener according to claim 1, characterized in that: The first chain assembly further comprises a chain connecting plate; one end of the chain connecting plate is fixedly connected to one end of the chain, and a rivet is provided at the bottom of the other end, the rivet is provided with a circular groove, and an open ring is clamped in the circular groove; A mounting plate is provided on one side of the first window sash connecting block, and a connecting hole is provided on the mounting plate; the bottom end of the rivet is clamped in the connecting hole, and the chain connecting plate is fixedly connected to the first window sash connecting block through the open ring; the first window sash connecting block and the second window sash connecting block are symmetrically arranged.

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