Back support attachment system for office chair

Abstract

To provide an office chair with a seat back attachment system that provides efficient shipment and ease of installation.SOLUTION: A back support for a chair includes a seat back attachment system that provides efficient shipping and ease of installation. The attachment system includes a seat back and a seat that are mounted on a base. The seat back has a support portion and an attachment portion. The support portion has a forward surface for supporting the back of a user. A locking element is connected between the attachment portion and the base, the locking element locks the attachment portion in place with respect to the base, and the locking element is capable of toolless attachment to the base.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention is directed to an office chair, and more particularly to an office chair that can be manufactured efficiently and shipped and installed efficiently.

Background Art

[0002] In the competitive market of office seating, users are seeking office seating options that provide comfort, functionality, and a high degree of adjustability. However, these chairs must also be cost-effective in terms of purchase, manufacture, and shipping. As a result, office chair manufacturers are constantly seeking improved methods of manufacturing office chairs and their components, as well as improved methods of boxing and shipping these chairs and components.

[0003] Some office chairs have increased manufacturing efficiency by reducing or simplifying components such as back supports or mechanisms. For example, some modern office chairs have shifted to a one-piece backrest that is typically molded as a single unit to form a plastic shell, thus reducing the number of backrest components from many elements that require assembly to a single element that can be easily attached to an office chair base. Other office chairs have reduced the size of the chair mechanism, typically a series of controls and springs, and the number of spring elements within the mechanism, for the purpose of simplifying the assembly process and reducing weight for shipping. Still other office chairs are designed with "quick-connect" backrests, such that the chair can be shipped without the backrest attached for the purpose of reducing the packing size required for the chair. These backrests are then attached to the chair base after shipping and removal from the packaging.

[0004] However, each of the efforts at efficiency pointed out above has drawbacks, including aesthetic issues, comfort, and a reduction in the features for adjustment and an increase in the work for installers who may need to partially assemble the product after it has been shipped. As a result, manufacturers continue to seek an efficiency that can minimize these and other drawbacks.

SUMMARY OF THE INVENTION

[0005] The present invention provides an office chair with a backrest attachment system that provides efficient shipping and easy installation. The attachment system includes a backrest and a seat portion assembled on a base. The backrest has a support portion and an attachment portion. The support portion has a front surface for supporting the user's back. A locking element is connected between the attachment portion and the base, and the locking element locks the attachment portion in a predetermined position in relation to the base, and the locking element can be attached to the base without using tools.

[0006] In one embodiment, prior to the connection of the locking element, the backrest is pivotable between a shipping position and an upright position in relation to the chair base, and the connection of the locking element locks the backrest in the upright position. The locking element may be a pin or an elongated rod, and the chair base may define a locking element receptacle into which the pin can be inserted. The pin may include a first end, a second end, and a longitudinal length between the ends, and the pin may define a notch along the longitudinal length. The base may include an elastic element that extends into the notch at the time of insertion of the pin to prevent removal of the pin.

[0007] In one embodiment, the base includes a rod for assembling the back support, and the mounting portion of the backrest is connected to the rod for assembling the back support. The back support may be connected to the base via a bracket for assembling the back support mounted on the rod for assembly. The mounting portion of the back support includes a back support bracket. The mounting portion of the back support includes a first portion connected to the back support bracket and a second portion defining an open slot receptacle for receiving the rod for assembly.

[0008] The present invention further includes a method for installing a backrest on an office chair, the method comprising: providing a base for an office chair having a top surface, a backrest support rod, and a lock receptacle; assembling a seat on the base for the office chair, the seat extending over at least a portion of the top surface of the base and having a top surface for supporting a user; attaching a support bracket to the support rod such that the support bracket is pivotable about the support rod; providing a backrest having a support portion and a mounting portion, the support portion having a user support surface; connecting the backrest mounting portion to the support bracket such that the backrest is pivotable about the support rod; pivoting the backrest to a shipping position where the user support surface of the backrest faces the top surface of the chair base; providing a locking element with the office chair, the locking element being insertable into the lock receptacle to hold the backrest in an upright position and prevent pivoting of the backrest to the shipping position when pivoting the backrest from the shipping position to the upright position; comprising.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

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Figure 5

DETAILED DESCRIPTION OF THE INVENTION

[0010] An office chair having a backrest attachment system according to a current embodiment of the present invention is shown in FIGS. 1 - 5 and is generally designated 10. Specifically, the embodiment of the office chair 10 disclosed in the present application includes a back support structure 12 for supporting the user's back, a seat 14 for supporting the user, and a base 20 for supporting the seat 14 and the back support 12. As will be disclosed in more detail below, the present invention includes a system and method for attaching the back support 12 to the base 20 in a manner that provides efficient shipping and easy installation by an installer or end - user. The system includes an attachment portion 22 of the backrest 12 that is configured to connect to the base 20 in such a way that the backrest 12 can be folded onto the seat 14 for shipping, then removed from the box and pivoted to an upright use position, held in place in the upright position by a locking element 24 that can be positioned (i.e., tool - less insertion) on the base 20 without the use of a separate tool, and held in a predetermined location on the base 20 by a lock receptacle 26.

[0011] Referring to FIG. 1, the base 20, seat portion 14, and backrest 12 are shown in an exploded view. A more detailed exploded view of the base 20 is shown in FIG. 2. The base 20 may be arranged in various forms depending on the characteristics and design of the particular office chair 10. The base 20 generally forms a central hub for the components of the office chair 10 and, in one embodiment, forms a housing 25 having a pair of sidewalls 28. The sidewalls 28 may be spaced apart from each other and, in one embodiment, each include an outer surface 30 and an inner surface 32 that extend in a front - rear direction that is parallel to the ground and a vertical direction that is perpendicular to the ground when the chair 10 is in use. The inner surfaces 32 may face each other. A bottom wall 34 may extend between the inner surfaces 32 of the sidewalls 28 and, in the illustrated embodiment, the bottom wall 34 defines a cylindrical opening 36 for receiving a conventional office chair pedestal (not shown) that may extend vertically from a ground - engaging unit having a series of legs supported on casters. The base 20 is supported above the ground by the pedestal and the ground - engaging unit.

[0012] Referring again to FIG. 2, the base housing 25 forms a housing and support for various systems of the office chair 10. For example, the base housing 25 includes a structure for supporting the seat 14. In the illustrated embodiment, this structure includes a pair of seat support rails 40 each assembled on one of the side walls 28. The seat support rails 40 are spaced apart from each other and each includes a top surface 42 and an outer edge 44. Referring to FIG. 1, the seat support rails 40 may include a structure for slidably connecting to the seat 14, such as a track (not shown) on the lower surface 47 of the seat 14 that extends around the rail 40 and is slidably attached to the rail 40 via the front edge 48 or the rear edge 51 of the rail 40. As shown, the rail 40 includes a tension tab 52 on the outer edge 44 that can bias against the seat 14 to absorb any slack between the seat 14 and the rail 40. The rail 40 may be assembled on an inclined portion 53 of the housing 25 that pivots about an axis 57 to allow the backrest 12 to recline from an upright position (shown in FIG. 4) to a reclining position. The housing 25 may similarly store one or more components of an inclination tension mechanism for controlling the degree of tension experienced by the user as the backrest 12 is reclined. For example, in the illustrated embodiment, the housing 25 stores a tension spring 55 connected to the inclined portion 53 of the housing for the purpose of biasing the backrest 12 to a vertical position. In another embodiment, the base housing 25 may include a different or alternative structure for assembling the seat 14, such as a structure for attaching the seat 14 to the top surface 42 of the rail.

[0013] The seat portion 14 includes an upper surface 45 and a lower surface 47. As pointed out, the lower surface 47 may include a structure such as a track or a mounting portion that enables the attachment of the seat portion 14 to the base 20. The upper surface 45 of the seat portion 14 forms a user support surface and generally faces away from the ground when the chair is in use. The seat portion 14 includes a cushion or an elastomeric fabric material to provide comfort to the user sitting on the upper surface 45.

[0014] The base housing 25 further includes a structure for attachment to the back support 12. As illustrated, the base housing 25 includes a backrest support rod 50 that is generally formed as a cylindrical rod and extends between side walls 28. Although the positioning and shape of the support rod 50 may vary, the support rod 50 of the illustrated embodiment is positioned adjacent to the upper edge 52 of the side wall 28 and the rear edge 54 of the side wall 28. Referring to FIGS. 1 and 3, in one embodiment, the backrest attachment system 10 includes a backrest support bracket 56 that provides a connection between the base 20 and the backrest 12. In one embodiment, the support bracket 56 is a U-shaped bracket having a central web 60 and a pair of lateral webs 62 extending from the central web 60. As illustrated, each lateral web 62 includes a series of mounting holes that align through both lateral webs 62, including a pair of mounting holes 64, a support rod hole 66, and a lock receptacle hole 68. The support bracket 56 is pivotally connected to the base housing 25 such that the support rod 50 extends through the support rod hole 66 of the bracket 56 in a manner that allows the bracket 56 to rotate about the support rod 56 between the folded "shipping" position shown in FIG. 3 where the backrest 12 is folded onto the seat portion 14 and the upright position shown in FIG. 4 where the backrest 12 forms an angle that is approximately perpendicular in relation to the seat portion 14 and is considered to enable a user to sit on the seat portion 14.

[0015] Referring to FIG. 1, the backrest 12 includes an upright portion or occupant support portion 80 and an attachment portion 22. The upright portion 80 is generally conventional and may be structured in various configurations. In the illustrated embodiment, the upright portion 80 includes a backrest frame 82 having a pair of upright members 84, an upper member 86 extending between the upright members 84 at the upper ends of the upright members 84, and a lower member 88 extending between the upright members 84. The frame 82 forms a structural ring shape having a front surface 90 and a rear surface 92. The front surface 90 may support a shell 94 that supports the occupant's back. The shell 94 has a rear surface 96 facing the frame 82 and a front surface 98 facing opposite and engaging the user's back with reference to FIG. 4. In another embodiment, the frame 82 or the shell 94 may similarly support a cushion or upholstery material, and in another embodiment, the frame may support a load-bearing fabric in a tensioned state.

[0016] The attachment portion 22 extends from the backrest frame 82 to form a structure for attachment to the chair base 20. More specifically, as shown in FIG. 1, the attachment portion 22 includes a pair of spaced walls 100 that extend forwardly from the front surface 90 of the lower member 88 of the claim 82. The walls 100 of the attachment portion 22 include a series of holes for attaching the backrest 12 to the base 20 and for mating with the locking element 24 as will be pointed out in more detail below. As shown in FIG. 1, each of the walls 100 defines an open receptacle 102 at the leading edge 105 of each wall 100. The open receptacle 102 is sized to receive the support rod 50. Each of the walls 100 additionally includes a lock receptacle hole 106 and a pair of attachment holes 108. The receptacle 102 is positioned such that the wall 100 of the backrest 12 aligns with the support rod hole 66 when the wall 100 is fitted onto the side web 62 of the bracket 56, and the attachment holes 108 and the lock receptacle hole 106 are positioned to align with the attachment hole 64 and the lock receptacle hole 68 of the bracket 56. To firmly attach the attachment portion 22 to the bracket 56, a fastener 70 may be inserted through each of the aligned attachment holes 108, 64. In one alternative embodiment, the walls 100 may include one or more attachment holes 108 and lock receptacle holes 106, and the positioning of these holes may vary for each field of use.

[0017] In one embodiment, the base housing 25 similarly includes a lock receptacle 26 and a lock element 24. The lock receptacle 26 is formed in such a manner that inserting the lock element 24 into the lock receptacle 26 prevents further pivoting of the backrest 12 in relation to the support rod. Referring to FIGS. 1-5, the lock receptacle 26 is an opening extending through the base housing 25, including a receptacle hole 110 that extends through both side walls 28. These receptacle holes 110 are positioned such that when the attachment portion 22 is attached to the bracket 56 and the backrest 12 is pivoted to the upright position, they are aligned with the lock receptacle hole 106 of the attachment portion 22 of the backrest 12 and the lock receptacle hole 68 of the bracket 56. The lock element 24 is sized and shaped such that it can be inserted through the lock receptacle 26 with the seat in the upright position. In one embodiment, the lock element 24 is an elongated rod having a first end 112 and a second end 114 that define a longitudinal length therebetween. The ends 112, 114 may be rounded to facilitate insertion into the lock receptacle 26. The length of the rod 24 is sufficient to extend through at least one of the side wall 28 of the housing 25 and the wall 100 of the attachment portion 22 of the backrest 12, and in the illustrated embodiment, this length is sufficient to extend through both side walls 28 of the base housing 25.

[0018] In one embodiment, the base housing includes a retaining element 120 that acts to retain the locking element 24 within the lock receptacle 26 at the time of insertion of the locking element 24. Referring to FIG. 2, the retaining element 120 is an elastic element such as spring steel having a first section 122 and a second section 124 extending at an angle from the first section 122. The first section 122 defines a mounting hole 126 for attaching the first section 122 to a screw boss 130 on the bottom wall 32 of the base housing 25. The second section 124 extends at an angle from the first section 122 such that at least a portion of the second section 124 interferes with the lock receptacle 26, for example, by at least partially extending into the path of the locking element 24 when the locking element 24 is inserted into the lock receptacle 26. As illustrated, the locking element 24 defines a circumferential notch 132 along its longitudinal length that aligns with and receives at least a portion of the retaining element 120 at the time of complete insertion of the locking element 24 into the lock receptacle 26. As a result of the retaining element 120 having a certain degree of elasticity, the retaining element 120 snap-fits into the notch 132 at the time of insertion of the locking element 24 and prevents removal of the locking element 24 from the lock receptacle 26 without using a tool to bend the retaining element away from the notch 132.

[0019] During operation, the mounting system 10 for an office chair can be assembled and shipped with the housing 25 provided on the chair base 20. The seat support bracket 56 can be attached to the housing 25 by inserting the backrest support rod 50 through the support rod hole 66 of the bracket 56. This connection enables the seat support bracket 56 to pivot about the support rod 50. The seat 14 may be attached to the base 20 by a conventional method. In the illustrated embodiment, the seat 14 is attached to the base by sliding a track on the bottom surface of the seat 14 onto the seat support rail 40 on the base housing 25. The backrest 12 is attached to the base 20 by attaching the attachment portion 22 of the backrest 12 to the bracket 56. In one embodiment, this attachment is accomplished by inserting the support rod 50 into the open receptacle 104 on the attachment portion 22, aligning the attachment hole 108 on the attachment portion 22 with the attachment hole 64 on the bracket 56, and inserting a fastener 70 through the attachment holes 108, 64 to connect the bracket 56 to the attachment portion 22. At the time of attaching the backrest 12 to the base 20, the backrest 12 is pivotable about the support rod 50 together with the bracket 56 between the folded shipping position and the upright position shown in FIG. 3, where the front surface 98 of the backrest shell 94 faces the upper surface 45 of the seat 14 and generally faces in the direction of the upper surface 42 of the seat support rail 40. In this folded position of the backrest 12, the seat 14 can be slid forward on the rail 40 to expose the rear portion of the rail 40 as shown in FIG. 3. In this position, ground engaging structures such as pedestals and ground supports may also be attached to the base housing 25, and the system 10 with the folded backrest 12 may be stored in a box or other container together with the locking element 24.

[0020] When the folding seat system 10 is taken out of the box, the installer or user can pivot the backrest 12 about the support rod 50 to the upright position shown in FIG. 4, where the lock receptacle holes 106 on the attachment portion 22 are aligned with the lock receptacle holes 110, and the lock element 24 may be inserted into the lock receptacle 26. In particular, in the illustrated embodiment, the lock element 24 can be inserted into the lock receptacle 26 without using a separate tool. As the rounded first end 112 of the lock element 24 is inserted through the resilient retaining element 120, the retaining element may be pivoted slightly by the force of the lock element 24. Next, as the lock element 24 is fully inserted into the lock receptacle 26, the retaining element 120 snaps into the notch 132 on the lock element 24 to retain the lock element 24 within the lock receptacle 26. When the lock element 24 is inserted through the lock element hole 106 of the attachment portion 22 of the backrest 12, further free rotation of the backrest 12 about the support rod 50 is prevented. The seat 14 may slide rearwardly in the direction of the backrest 12 to its use position, where the user can sit on the seat 14 with their back supported on the backrest 12.

[0021] Alternative embodiments of a foldable backrest or a quick-connect backrest that can be attached to the chair base after shipment are similarly contemplated. For example, the attachment portion of the backrest may be structured to be inserted into a receptacle on the chair base, and the receptacle may house a locking mechanism to retain the attachment portion at the time of insertion. The locking mechanism may include a portion that moves at the time of insertion of the attachment portion to lock the attachment portion to the chair base. For example, the attachment portion may include a notch for receiving a spring-biased pin at the time of insertion of the attachment portion into the receptacle.

[0022] Terms indicating directions such as "vertical", "horizontal", "top", "bottom", "upper", "lower", "inner", "inwardly", "outer", and "outwardly" are used to assist in explaining the present invention based on the orientation of the illustrated embodiments. The use of terms indicating directions should not be construed as limiting the present invention to any specific orientation.

[0023] The above description is of the current embodiments of the present invention. Various modifications and changes can be made without departing from the spirit and broader aspects of the present invention as defined in the appended claims, and these should be construed in accordance with the principles of patent law, including the doctrine of equivalents. This disclosure is presented for illustrative purposes and should not be construed as an exhaustive description of all embodiments of the present invention or as limiting the scope of the claims to the specific elements exemplified or described in connection with these embodiments. For example, without limitation, any individual element of the described invention may be replaced with alternative elements that provide substantially similar functionality or proper operation in another form. This includes, for example, currently known alternative elements such as those that may be known to those skilled in the art at present, and potentially future-developed alternative elements such as those that may be recognized as one alternative by those skilled in the art at the time of development. Further, the disclosed embodiments include a plurality of features that may be considered to simultaneously describe and cooperate to provide a series of advantages. The present invention is not limited to only those embodiments that include all of these features or provide all of the stated advantages, unless otherwise specified within the issued claims. For example, any reference to a singular claim element using the articles "a", "an", "the", or "said" should not be construed as limiting that element to being singular.

Claims

1. In an attachment system for a back support for an office chair: A chair base; A backrest having a support portion and an attachment portion, the support portion having a front surface for supporting a user's back; A seat portion assembled on the chair base, the seat portion having a top surface for supporting a user; A locking element connected between the attachment portion of the backrest and the base, the locking element locking the attachment portion in a predetermined position relative to the base and being attachable to the base without using tools; An attachment system including the above.

2. The attachment system according to claim 1, wherein prior to the connection of the locking element, the backrest is pivotable between a shipping position and an upright position in relation to the chair base, and the connection of the locking element locks the backrest in the upright position.

3. The attachment system according to claim 2, wherein the locking element is a pin, the base defines a locking element receptacle, and the pin is inserted into the receptacle.

4. The attachment system according to claim 3, wherein the pin includes a first end, a second end, and a longitudinal length between the ends, and the pin defines a notch along the longitudinal length.

5. The attachment system according to claim 4, wherein the base includes an elastic element extending into the notch at the time of insertion of the pin to prevent removal of the pin.

6. The attachment system according to claim 5, wherein the base includes a rod for assembling the back support, and the attachment portion of the backrest is connected to the rod for assembling the back support.

7. The attachment system according to claim 6, wherein the base includes a bracket for assembling the back support assembled on the rod for assembling, the attachment portion of the back support includes a back support bracket, and the attachment portion of the back support includes a first portion connected to the back support bracket and a second portion defining an open slot receptacle for receiving the rod for assembling.

8. In a back support attachment system: A chair base having a locking receptacle; A seat portion assembled on the chair base, the seat portion having a top surface for supporting a user; A backrest having a support portion and a mounting portion, the support portion having a front surface for supporting a user's back, the backrest being pivotally connected to the base so as to be movable between a folded shipping position and an upright position in which the front surface of the backrest faces the upper surface of the seat; A locking element that can be inserted into the lock receptacle without using a tool to lock the backrest in the upright position; A back support mounting system including the same.

9. The chair base includes a locking spring, and the locking spring engages the locking element at the time of insertion of the locking element to hold the locking element in the lock receptacle. The back support mounting system according to claim 8.

10. The locking element is a locking pin having a first end, a second end, and a longitudinal length therebetween, the locking pin defining a notch along a portion of the longitudinal length, and the locking spring extending into the notch at the time of insertion of the locking element into the lock receptacle. The back support mounting system according to claim 9.

11. The base includes a rod for assembling the back support, and the mounting portion of the backrest is connected to the rod for assembling the back support. The back support mounting system according to claim 10.

12. The base includes a bracket for assembling the back support assembled on the rod for assembling, the mounting portion of the back support includes a back support bracket, and the mounting portion of the back support includes a first portion connected to the back support bracket and a second portion defining an open slot receptacle for accommodating the rod for assembling. The back support mounting system according to claim 11.

13. In a method of installing a backrest on an office chair: Providing a base for an office chair having an upper surface, a backrest support rod, and a lock receptacle; Assembling a seat on the base for the office chair, the seat extending over at least a portion of the upper surface of the base, the seat having an upper surface for supporting a user. A step of attaching a support bracket, the step of attaching the support bracket to the support rod such that the support bracket is pivotable about the support rod; A step of providing a backrest having a support portion and an attachment portion, the step that the support portion has a user support surface; A step of connecting the backrest attachment portion to the support bracket such that the backrest is pivotable about the support rod; A step of pivoting the backrest to a shipping position where the user support surface of the backrest faces the upper surface of the chair base; A step of providing a locking element together with the office chair, the step that the locking element is insertable into the lock receptacle to hold the backrest in the upright position and prevent pivoting of the backrest to the shipping position when the backrest is pivoted from the shipping position to the upright position; A method including the above.

14. The method according to claim 13, wherein the lock receptacle extends through at least one of the base, and the backrest attachment portion and the support bracket, and thus the insertion of the lock element includes the insertion of the lock element through at least one of the chair base and the backrest and the support bracket.

15. The method according to claim 14, wherein the lock receptacle is an elongated pin.

16. The method according to claim 15, including a step of providing a lock retainer on the base, the lock retainer engaging the lock element at the time of insertion of the lock element to prevent removal of the lock element.

17. The method according to claim 16, wherein the lock element defines a notch, and the lock retainer engages the notch at the time of insertion of the lock element into the lock retainer.

18. The method according to claim 17, wherein the lock retainer is a spring steel element that snaps into the notch as the notch is inserted through the lock retainer.

19. The method according to claim 18, wherein the step of connecting the backrest attachment portion to the support bracket includes a step of extending a fastener through the backrest attachment portion and the support bracket.

20. The method according to claim 19, wherein the backrest attachment portion includes an open receptacle, and the step of connecting the backrest attachment portion to the support bracket includes inserting the backrest support rod into the open receptacle.

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