Backrest, bed frame and bed
The design of a detachable backpack and an angle adjustment mechanism solves the problems of backrest foam collapse and non-adjustable tilt angle, extending the service life and improving the user experience.
Patent Information
- Application Number
- CN202423319175.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-12-31
AI Technical Summary
The existing sponge filling in the backrest is prone to collapse, affecting the usability, and the tilt angle of the support surface is not adjustable, resulting in a poor user experience.
Design a detachable backpack with an angle adjustment mechanism. The backpack is detachably connected to the back panel, and the angle adjustment mechanism is used to adjust the tilt angle of the support surface and fix the backpack with a limiting component. The support surface can be adjusted as needed.
It extends the lifespan of the backrest, improves user comfort and experience, and solves the problems of foam collapse and non-adjustable tilt angle through the design of a detachable backpack and angle adjustment mechanism.
Smart Images

Figure CN223529189U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of home furnishing technology, and in particular to a headrest, bed frame and bed. Background Technology
[0002] In the home furnishing industry, some furniture pieces, such as beds and sofas, are designed with backrests for people to lean against. In related technologies, to improve backrest comfort, a backrest is often fitted with a cushion filled with elastic materials like foam. However, these elastic materials tend to collapse after being pressed against for a period of time, affecting subsequent use and reducing the user experience. Furthermore, the tilt angle of the backrest's support surface is often not adjustable, resulting in a poor user experience. Utility Model Content
[0003] To solve at least one of the above-mentioned technical problems, this application provides a backrest, a bed frame, and a bed, and the technical solution adopted is as follows.
[0004] This application provides a backrest, including:
[0005] Back panel;
[0006] A backpack, wherein the backpack is detachably connected to the back panel, and the backpack includes a support surface exposed on the back panel;
[0007] An angle adjustment mechanism is connected to the backpack and is used to adjust the tilt angle of the support surface.
[0008] The backrest provided in this application has at least the following technical effects: Firstly, the backpack and back panel are detachably connected. If the backpack collapses or otherwise affects its use after a period of use, the backpack can be removed and replaced with a new one, extending the lifespan of the backrest and improving user comfort. Secondly, the tilt angle of the backpack's support surface can be adjusted via an angle adjustment mechanism, allowing the user to lean against it. Therefore, the user can adjust the tilt angle of the support surface according to their needs, improving the user experience.
[0009] In some embodiments of this application, the backrest further includes a limiting component, and the back panel has a first receiving groove, the limiting component being used to fix at least a portion of the backpack in the first receiving groove.
[0010] In some embodiments of this application, the bottom of the backpack is provided with a slot, the first receiving slot includes a first sidewall, and the backpack is inserted into the first sidewall through the slot so that a part of the backpack is located in the first receiving slot and another part of the backpack is located outside the first receiving slot.
[0011] In some embodiments of this application, the angle adjustment mechanism includes an adjusting member and a driving member. The adjusting member is rotatably connected to the first sidewall. The adjusting member is used to tilt the portion of the backpack located outside the first receiving slot by rotating itself, thereby adjusting the tilt angle of the support surface. The driving member is connected to the adjusting member to drive the adjusting member to rotate.
[0012] In some embodiments of this application, the limiting component includes a first connector and a second connector, the first connector being mounted on the back panel and the second connector being mounted on the backpack, and the first connector and the second connector being detachably connected.
[0013] In some embodiments of this application, the backpack includes a protective cover and a filler, the filler being disposed inside the protective cover, and the protective cover having an opening and closing mechanism for opening and closing the protective cover.
[0014] This application also provides a bed frame, including a bed frame body and the aforementioned backrest, wherein the backrest is connected to the bed frame body by one side of the backpack.
[0015] In some embodiments of this application, the bed frame body includes a bed board and support legs. One end of the bed board is movably connected to the back panel, and the bottom of the bed board is provided with multiple support legs, the height of which is adjustable.
[0016] In some embodiments of this application, the support leg includes a first part, a second part, and a reinforcing member. One end of the first part is connected to the bed board, and the other end of the first part is adjustablely connected to the second part. The reinforcing member is used to lock the first part and the second part together.
[0017] This application also provides a bed, including the bed frame described above. Attached Figure Description
[0018] The aspects and advantages described and / or added to the embodiments of this application will become apparent and readily understood in conjunction with the following drawings. It should be noted that the embodiments illustrated in the following drawings are exemplary and are used only to explain this application, and should not be construed as limiting this application.
[0019] Figure 1 This is a schematic diagram of the backrest structure provided in an embodiment of this application;
[0020] Figure 2 This is a schematic diagram of the backrest structure without a backpack provided in an embodiment of this application;
[0021] Figure 3 This is a schematic diagram of the backpack structure provided in an embodiment of this application;
[0022] Figure 4 A partial cross-sectional view of the backrest provided in an embodiment of this application;
[0023] Figure 5 for Figure 4 Enlarged view of section B;
[0024] Figure 6 Another partial cross-sectional view of the backrest provided in an embodiment of this application;
[0025] Figure 7 for Figure 1 Enlarged view of section A;
[0026] Figure 8 This is a schematic diagram of the bed frame provided in an embodiment of this application;
[0027] Figure 9 This is another structural schematic diagram of the bed frame provided in an embodiment of this application;
[0028] Figure 10 for Figure 9 Enlarged view of section C;
[0029] Figure 11 This is a cross-sectional view of the mounting component and support leg provided in the embodiments of this application.
[0030] Figure label:
[0031] Backrest 100, back panel 110, first receiving slot 111, first side wall 1111, second receiving slot 112, third connector 113, backpack 120, support surface 121, card slot 122, protective cover 123, opening and closing part 1231, filling material 124, angle adjustment mechanism 130, adjustment part 131, pivot 132, drive part 133, controller 134, first chain tooth 141, second chain tooth 142, Velcro nap 143, Velcro barbed side 144;
[0032] Bed frame 211, first side frame 2111, second side frame 2112, first mounting part 21131, second mounting part 21132, third mounting part 21133, first fastener 21134, second fastener 21135, support part 21136, bed board body 212, support leg 220, first part 221, threaded hole 2211, second part 222, external thread 2221, reinforcement part 223. Detailed Implementation
[0033] The following is combined with Figures 1 to 11The embodiments of this application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.
[0034] In the description of this application, it should be understood that the use of terms such as "center," "middle," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" to indicate orientation or positional relationships is based on the orientation or positional relationships shown in the accompanying drawings and is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, features defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.
[0035] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0036] See Figure 1 and Figure 2 This application provides a backrest 100, which includes a back panel 110, a backpack 120, and an angle adjustment mechanism 130. The backpack 120 is detachably connected to the back panel 110 and includes a support surface 121 exposed on the back panel 110. The angle adjustment mechanism 130 is connected to the backpack 120 and is used to adjust the tilt angle of the support surface 121.
[0037] Understandably, on the one hand, since the backpack 120 and the back panel 110 are detachably connected, if the backpack 120 collapses or otherwise affects its use after a period of use, it can be removed and replaced with a new backpack 120, which can extend the service life of the backrest 100 and improve user comfort. On the other hand, the tilt angle of the support surface 121 of the backpack 120 can be adjusted through the angle adjustment mechanism 130. The support surface 121 can be used for the user to lean against, so the user can adjust the tilt angle of the support surface 121 according to their needs, which can improve the user experience.
[0038] It is understood that backpack 120 can be set to one or more, and the number of backpacks 120 can be set according to actual needs, without specific limitations here. For example, see... Figure 1 Backpack 120 can be set to two, and the two backpacks 120 can be set at intervals along the width direction of the back panel 110.
[0039] Optionally, the number of angle adjustment mechanisms 130 can be the same as the number of backpacks 120 and correspond one-to-one. For example, two angle adjustment mechanisms 130 are provided, corresponding one-to-one with backpacks 120. Of course, the number of angle adjustment mechanisms 130 can also be adjusted according to actual conditions, and no specific limitation is made here.
[0040] Optionally, in some embodiments, the backrest 100 further includes a limiting component, and the back panel 110 has a first receiving groove 111, the limiting component being used to fix at least a portion of the backpack 120 in the first receiving groove 111.
[0041] It is understandable that by creating a first receiving slot 111 in the back panel 110 to accommodate at least part of the backpack 120, the space occupied by the backrest 100 can be reduced while ensuring user comfort. By setting a limiting component, the backpack 120 can be secured, thereby improving the stability of the backpack 120.
[0042] Optionally, the number of limiting components and the first receiving slots 111 can be the same as the number of backpacks 120 and correspond one-to-one. For example, there are two limiting components and two first receiving slots 111, each corresponding to one backpack 120. Of course, the number of limiting components and the first receiving slots 111 can be adjusted according to the actual situation, and no specific limitation is made here.
[0043] Alternatively, in some embodiments, see Figure 3 The bottom of the backpack 120 has a card slot 122, see [reference]. Figure 2 The first receiving groove 111 includes a first sidewall 1111, see [link / reference] Figure 4The backpack 120 is inserted into the first side wall 1111 via the slot 122, so that a part of the backpack 120 is located in the first receiving slot 111 and the other part of the backpack 120 is located outside the first receiving slot 111.
[0044] Alternatively, in some embodiments, see Figure 5 and Figure 6 The angle adjustment mechanism 130 includes an adjusting member 131 and a driving member 133. The adjusting member 131 is rotatably connected to the first side wall 1111. The adjusting member 131 is used to tilt the part of the backpack 120 located outside the first receiving slot 111 by rotating itself, thereby adjusting the tilt angle of the support surface 121. The driving member 133 is connected to the adjusting member 131 to drive the adjusting member 131 to rotate.
[0045] It is understandable that the backpack 120 itself has a certain degree of elastic deformation, so under the action of the adjusting component 131, the backpack 120 can deform to a certain extent to tilt.
[0046] Optionally, the adjusting member 131 may include an adjusting plate. Of course, the adjusting member 131 may also include other adjusting structures such as adjusting blocks, and no specific limitations are made here.
[0047] For example, a through groove is provided on the first sidewall 1111, the adjusting member 131 is disposed in the through groove, and the top of the adjusting member 131 is connected to the upper sidewall of the through groove through a rotating member. Optionally, the rotating member can be a rotating shaft 132.
[0048] Optionally, see Figure 6 The back plate 110 also has a second receiving groove 112 on the side of the adjusting member 131 facing the first receiving groove 111, and the driving member 133 is housed in the second receiving groove 112. Optionally, the second receiving groove 112 can communicate with the first receiving groove 111. The driving member 133 is connected to the adjusting member 131 to drive the adjusting member 131 to rotate around the rotating member, thereby adjusting the tilt angle of the support surface 121.
[0049] Optionally, the drive unit 133 includes an electric telescopic rod, one end of which is hinged to the bottom wall of the second receiving groove 112, and the other end is hinged to the adjusting member 131. By controlling the extension and retraction of the electric telescopic rod, the adjusting member 131 can be controlled to rotate around the pivot 132, thereby causing the portion of the backpack 120 located outside the first receiving groove 111 to tilt, and thus the tilt angle of the support surface 121 can be adjusted.
[0050] Optionally, the angle adjustment mechanism 130 further includes a controller 134, which is electrically connected to the drive member 133 to control the opening, closing, and operating conditions of the drive member 133. For example, the controller 134 is electrically connected to the electric telescopic pole to control the opening, closing, and extension / retraction degree of the electric telescopic pole.
[0051] Optionally, in some other embodiments, the drive member 133 may include an electric rotating shaft, and the top of the adjusting member 131 is connected to the upper side wall of the through groove through the electric rotating shaft. The tilt angle of the support surface 121 can be controlled by controlling the rotation angle of the electric rotating shaft, which will not be elaborated here.
[0052] Optionally, in some embodiments, the limiting component includes a first connector and a second connector, the first connector being mounted on the back panel 110 and the second connector being mounted on the backpack 120, and the first connector and the second connector being detachably connected.
[0053] Optionally, see Figure 1 and Figure 7 The first connector includes a first chain tooth 141, and the second connector includes a second chain tooth 142 that mates with the first chain tooth 141. A first pull ring is provided on the first chain tooth 141 or the second chain tooth 142. The first pull ring is used to pull the first chain tooth 141 and the second chain tooth 142 together or apart.
[0054] For example, see Figure 2 The first receiving groove 111 includes a second sidewall disposed opposite to the first sidewall 1111, and the first chain tooth 141 may be disposed at the upper edge of the second sidewall, see [reference]. Figure 3 The second chain tooth 142 can be set at the upper edge of the backpack 120 to cooperate with the first chain tooth 141.
[0055] It is understandable that the specific number and location of the first chain tooth 141 and the second chain tooth 142 can be set according to actual needs, and no specific restrictions are imposed here.
[0056] Optionally, the first connector also includes a hook and loop side 143, and the second connector also includes a hook and loop side 144. The hook and loop side 143 and the hook and loop side 144 are connected to further secure the backpack 120 to the back panel 110.
[0057] For example, see Figure 2 and Figure 3 The hook and loop fastener 143 is disposed on the inner wall of the first receiving groove 111, and the hook and loop fastener barbed fastener 144 is disposed on the backpack 120 accordingly. It is understood that the specific number and specific placement of the hook and loop fastener 143 and the hook and loop fastener 144 can be set according to actual needs, and no specific restrictions are imposed here.
[0058] Of course, the first connector may include a hook and loop fastener 144, and the second connector may include a hook and loop fastener 143; no specific limitation is made here. Alternatively, the first connector and the second connector may also be connected by a snap-fit connection or other detachable connection structure; no specific limitation is made here.
[0059] Alternatively, in some embodiments, see Figure 3 The backpack 120 includes a protective cover 123 and a filler 124. The filler 124 is disposed inside the protective cover 123. The protective cover 123 is provided with an opening and closing component 1231 for opening and closing the protective cover 123.
[0060] Optionally, the opening and closing part 1231 can be a zipper. By opening the zipper, the filling material 124 in the protective cover 123 can be taken out and replaced, which can save the material of the protective cover 123 and reduce the user's usage cost.
[0061] Of course, the opening and closing parts 1231 can also be other opening and closing structures such as concealed snaps, and no specific restrictions are made here.
[0062] Optionally, the filling 124 may include a sponge, the surface of which may be covered with goose down. This configuration of the filling 124 can increase comfort and improve the user experience.
[0063] Optionally, the outer surface of the protective case 123 is provided with protrusions (not shown in the attached drawings), which are filled with goose down to improve the comfort of the surface of the protective case 123. It is understood that the specific number and location of the protrusions can be set according to actual needs, and no specific limitations are imposed here.
[0064] Optionally, the protective cover 123 can be a cloth cover.
[0065] Other configurations and operations of the backrest 100 according to the embodiments of this application are known to those skilled in the art and will not be described in detail here.
[0066] See Figure 8 This application embodiment also provides a bed frame, which includes a bed frame body and the aforementioned backrest 100. The side of the backrest 100 where the backpack 120 is provided is connected to the bed frame body, and the bed frame body is located below the backpack 120.
[0067] Optionally, in some embodiments, the bed frame body includes a bed board and support legs 220. One end of the bed board is movably connected to the back panel 110, and the bottom of the bed board is provided with multiple support legs 220, the height of which is adjustable.
[0068] It is understandable that the height of the bed board can be adjusted by adjusting the height of the support leg 220, thus meeting the needs of people with different requirements for bed height; and the height between the bed board and the backpack 120 can also be adjusted by adjusting the height of the support leg 220, thus making it suitable for people with different requirements for the height of the backpack 120.
[0069] Optionally, the bed board includes a bed frame 211 and a bed board body 212, with the bed frame 211 disposed on the outer periphery of the bed board body 212 and the support legs 220 disposed at the bottom of the bed frame 211. Optionally, the bed board body 212 is a slatted frame.
[0070] For example, see Figure 9 The bed frame 211 includes two first side frames 2111 and one second side frame 2112. One end of each of the two first side frames 2111 is connected to the back panel 110, and the other end of each of the two first side frames 2111 is connected to both ends of the second side frame 2112.
[0071] Optionally, the back panel 110 has a vertically movable third connector 113 located below the backpack 120, with the ends of the two first side panels 2111 away from the second side panel 2112 respectively connected to the third connector 113. Optionally, the third connector 113 can be a long strip-shaped connecting block. Of course, the third connector 113 can also be a connector of other structures, and no specific limitation is made here.
[0072] For example, the bed frame 211 also includes mounting members, and the first side frame 2111 and the second side frame 2112, as well as the first side frame 2111 and the third connecting member 113, are connected by the mounting members. Optionally, the second side frame 2112, the third connecting member 113 and the two first side frames 2111 enclose a square frame, and a mounting member is provided at each of the four corners of the square frame.
[0073] The following explanation uses the example of "the first frame 2111 and the third connector 113 being connected by an installation component".
[0074] Optionally, see Figure 10 The mounting component includes a first mounting part 21131 and a second mounting part 21132 connected together. The first mounting part 21131 is connected to the first frame 2111 by a first fastener 21134, and the second mounting part 21132 is connected to the third connector 113 by a second fastener 21135, so that the first frame 2111 and the third connector 113 can be assembled together.
[0075] For example, the first mounting part 21131 is a first mounting plate, the second mounting part 21132 is a second mounting plate, and the first mounting part 21131 is vertically connected to the second mounting part 21132.
[0076] The end face of one end of the first frame 2111 is pressed against the side of the third connector 113, the first mounting plate is pressed against the side of the first frame 2111, the second mounting plate is pressed against the side of the third connector 113, the first fastener 21134 passes through the first mounting plate and the first frame 2111, and the second fastener 21135 passes through the second mounting plate and the third connector 113, so as to install the first frame 2111 and the third connector 113 together.
[0077] Optionally, the first fastener 21134 and the second fastener 21135 can be fastening screws.
[0078] Optionally, see Figure 9 The controller 134 is mounted on one of the first frames 2111. Of course, the controller 134 can also be mounted on the back panel 110 or other locations, without any specific restrictions.
[0079] Optionally, the mounting component further includes a support portion 21136 for supporting the bed board body 212. Optionally, the support portion 21136 is a support plate, and the two adjacent sides of the support plate are perpendicularly connected to the first mounting portion 21131 and the second mounting portion 21132, respectively.
[0080] Optionally, the mounting components are all installed at the inner corners of the square frame, so that the support 21136 can be located inside the square frame, which facilitates the support of the bed board body 212.
[0081] Optionally, the mounting component may further include a third mounting portion 21133, which is integrally formed with the support portion 21136, and is used to mount the support legs 220. Optionally, there are four support legs 220, which are located at the bottom of the four corners of the square frame.
[0082] Optionally, in some embodiments, the support leg 220 includes a first part 221, a second part 222, and a reinforcing member 223. One end of the first part 221 is connected to the bed board, and the other end of the first part 221 is tunably connected to the second part 222. The reinforcing member 223 is used to lock the first part 221 and the second part 222.
[0083] Optionally, see Figure 11The upper end of the first part 221 is threadedly connected to the third mounting part 21133, and the lower end of the first part 221 is threadedly connected to the second part 222. Optionally, the lower end of the first part 221 has a threaded hole 2211, and the outer periphery of the second part 222 has an external thread 2221 that mates with the threaded hole 2211. The reinforcing member 223 is sleeved on the second part 222 and threadedly connected to the second part 222. By rotating the second part 222 within the threaded hole 2211, the relative position of the second part 222 and the first part 221 can be adjusted, thereby adjusting the height of the support leg 220. When the height of the support leg 220 is adjusted to a preset height, the reinforcing member 223 can abut against the lower end face of the first part 221 to prevent further relative movement between the first part 221 and the second part 222.
[0084] Other configurations and operations of the bed frame according to the embodiments of this application are known to those skilled in the art and will not be described in detail here.
[0085] This application embodiment also provides a bed, which includes the bed frame described above. Optionally, the bed also includes a mattress, which is placed on the bed board of the bed frame.
[0086] Optionally, the bed can be a soft bed. For example, the mattress is made of elastic materials such as springs, foam, and latex. This type of mattress provides appropriate support according to the curves and weight distribution of the human body, ensuring even support for all parts of the body, thereby reducing pressure points, improving user comfort, reducing the frequency of tossing and turning, and ultimately improving sleep quality.
[0087] Other configurations and operations of the bed according to the embodiments of this application are known to those skilled in the art and will not be described in detail here.
[0088] In the description of this specification, the use of terms such as "an embodiment," "some examples," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples" indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in the embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0089] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application.
[0090] In the description of this application, the presence of a comma ("、") in the patent title indicates an "and" relationship, not an "or" relationship. For example, if the patent title is "A type A, B type", it means that the content claimed in this application is: a technical solution with the subject matter title A and a technical solution with the subject matter title B.
Claims
1. A backrest, characterized in that, include: Back panel; A backpack, wherein the backpack is detachably connected to the back panel, and the backpack includes a support surface exposed on the back panel; An angle adjustment mechanism is connected to the backpack and is used to adjust the tilt angle of the support surface.
2. The backrest according to claim 1, characterized in that: The backrest also includes a limiting component, and the back panel has a first receiving groove. The limiting component is used to fix at least a portion of the backpack in the first receiving groove.
3. The backrest according to claim 2, characterized in that: The bottom of the backpack has a slot, and the first receiving slot includes a first sidewall. The backpack is inserted into the first sidewall through the slot, so that a part of the backpack is located in the first receiving slot and the other part of the backpack is located outside the first receiving slot.
4. The backrest according to claim 3, characterized in that: The angle adjustment mechanism includes an adjusting member and a driving member. The adjusting member is rotatably connected to the first side wall. The adjusting member is used to tilt the portion of the backpack located outside the first receiving slot by rotating itself, thereby adjusting the tilt angle of the supporting surface. The driving member is connected to the adjusting member to drive the adjusting member to rotate.
5. The backrest according to claim 2, characterized in that: The limiting component includes a first connector and a second connector. The first connector is mounted on the back panel, and the second connector is mounted on the backpack. The first connector and the second connector are detachably connected.
6. The backrest according to claim 1, characterized in that: The backpack includes a protective cover and a filling material, the filling material being disposed inside the protective cover, and the protective cover having an opening and closing mechanism for opening and closing the protective cover.
7. A bed frame, characterized in that, The device includes a bed frame body and a backrest as described in any one of claims 1 to 6, wherein the side of the backrest where the backpack is disposed is connected to the bed frame body.
8. The bed frame according to claim 7, characterized in that: The bed frame body includes a bed board and support legs. One end of the bed board is movably connected to the back panel. The bottom of the bed board is provided with multiple support legs, and the height of the support legs is adjustable.
9. The bed frame according to claim 8, characterized in that: The support leg includes a first part, a second part, and a reinforcing member. One end of the first part is connected to the bed board, and the other end of the first part is adjustablely connected to the second part. The reinforcing member is used to lock the first part and the second part together.
10. A bed, characterized in that, The bed frame includes any one of claims 7 to 9.