Chair assembled from blow-molded parts without tool

Abstract

A chair includes a lower block and an upper block. The lower block is put on the ground. The upper block includes a hollow seat and a hollow backrest. The hollow seat is installed on the lower block. The hollow backrest is installed on the hollow seat. The hollow seat is made via blow molding. The hollow backrest is made via blow molding.

Description

CROSS-REFERENCE

[0001] The present application is a continuation-in-part application of U.S. patent application Ser. No. 10/425373.

FIELD OF INVENTION

[0002] The present invention relates to a chair assembled from blow-molded parts without any tool.

BACKGROUND OF INVENTION

[0003] A typical chair includes a lower block and an upper block mounted on the lower block. The lower block includes a base for installment on the ground, a telescopic post mounted on the base, a control device connected with the telescopic post for control over the extending and shrinking of the telescopic post. The upper block includes a seat mounted on the control device, a backrest mounted on the seat and two armrests mounted on the seat. The seat, the backrest and the armrests are separately molded and then assembled. This practice however requires a lot of labor and time and therefore entails a high cost.

[0004] U.S. patent application Ser. No. 10/425373 discloses a chair including a lower block put on the ground and an upper block installed on the lower block. The upper block includes a hollow seat and a hollow backrest installed on the hollow seat. The hollow seat and the hollow backrest are both made via injection molding. The hollow seat and the hollow armrests are made of adequate sizes. Yet, only a little material is required since they are hollow. Adequate sizes provide sufficient strengths. A little material entails a low cost in fabrication. A little material results in a small weight that entails a low cost in transportation. Take the hollow seat for example, the injection molding requires a mold and an insert. The mold and the insert are both made of at least one part. The insert is put in the mold. Molten plastic material is injected in a space defined via the mold and the insert. After being cured, the upper block is removed from the mold, and the insert is removed from the hollow seat. It could be very difficult to remove the insert from the hollow seat.

[0005] The present invention is therefore intended to obviate or at least alleviate the problems encountered in prior art.

SUMMARY OF INVENTION

[0006] It is an objective of the present invention to provide a chair that can easily be manufactured.

[0007] It is another objective of the present invention to provide a chair that can be manufactured at a low cost.

[0008] It is another objective of the present invention to provide a chair that is strong in structure and light in weight.

[0009] According to the present invention, a chair includes a lower block and an upper block. The lower block is put on the ground. The upper block includes a hollow seat and a hollow backrest. The hollow seat is installed on the lower block. The hollow backrest is installed on the hollow seat.

[0010] The hollow seat and the hollow backrest may both be made via blow molding.

[0011] Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the attached drawings.

BRIEF DESCRIPTION OF DRAWINGS

[0012] The present invention will be described through detailed illustration of embodiments referring to the drawings.

[0013] FIG. 1 is an exploded view of a chair according to a first embodiment the present invention.

[0014] FIG. 2 is a perspective view of the chair shown in FIG. 1.

[0015] FIG. 3 is a cross-sectional view of the chair shown in FIG. 2.

[0016] FIG. 4 is a perspective view of a chair according to a second embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

[0017] Referring to FIGS. 1˜3, according to a first embodiment of the present invention, a chair 10 includes a lower block and an upper block mounted on the lower block.

[0018] The lower block includes a base 12 for installment on the ground, a telescopic post 14 mounted on the base 12, a control device 16 connected with the telescopic post for control over the extending and shrinking of the telescopic post 14. The lower block is conventional and hence will not further be described in detail.

[0019] The upper block includes a hollow seat 18 mounted on the control device 16 and a hollow backrest 20 mounted on the hollow seat 18. The hollow seat 18 and the hollow backrest 20 are both made via blow molding.

[0020] The hollow seat 18 includes an opening 22. The opening 22 is defined in the hollow seat 18 during blow molding of the hollow seat 18. The hollow seat 18 includes two apertures 24 drilled or punched therein.

[0021] The hollow backrest 20 includes a reduced neck 26 put in the opening 22 so as to connect the hollow backrest 20 with the hollow seat 18. The neck 26 includes two apertures 28 (only one is shown) drilled or punched therein. A bolt 30 is driven into the apertures 24 and 28 so as to secure the hollow backrest 20 to the hollow seat 18. The upper block is assembled from the hollow seat 18 and the hollow backrest 20 without any tool.

[0022] FIG. 4 shows a chair according to a second embodiment of the present invention. The second embodiment is identical to the first embodiment except for including two armrests 32 mounted on the hollow seat 18. The hollow seat 18 includes two cavities 34 defined in the top and four apertures 36 defined in the top. Two of the apertures 36 are located within each of the cavities 34. Each of the armrests 32 includes two inserts 38 extending from the bottom. The bottom of each of the armrests 32 is put in one of the recesses 34, thus attaching the armrests 32 to the hollow seat 18. The inserts 38 of each of the armrests 32 are inserted in the apertures 36 located within one of the recesses 34, thus securing the armrests 32 to the hollow seat 18. The upper block is assembled from the hollow seat 18, the hollow backrest 20 and the armrests 32 without any tool.

[0023] The present invention has been described via detailed illustration of three embodiments. Those skilled in the art can derive variations from the embodiments without departing from the scope of the present invention. Therefore, the embodiments shall not limit the scope of the present invention defined in the claims.

Claims

1. A chair including a lower block put on the ground and an upper block installed on the lower block, the upper block including a hollow seat and a hollow backrest installed on the hollow seat.

2. The chair according to claim 1 wherein the hollow seat is made via blow molding.

3. The chair according to claim 1 wherein the hollow backrest is made via blow molding.

4. The chair according to claim 1 wherein the hollow seat includes an opening defined therein, and the hollow backrest includes a reduced neck inserted in the opening.

5. The chair according to claim 4 wherein the opening is defined therein while molding the hollow seat.

6. The chair according to claim 5 further including a fastener, wherein the hollow seat includes an aperture defined therein, and the neck includes an aperture defined therein, and the fastener is driven into the apertures.

7. The chair according to claim 1 wherein the upper block includes two armrests mounted on the hollow seat.

8. The chair according to claim 7 wherein the hollow seat includes two apertures defined therein, and each of the armrests includes an insert extending from a lower end into one of the apertures.

9. The chair according to claim 7 wherein the hollow seat includes two cavities defined therein, and each of the armrests includes a lower end put in one of the cavities.

10. The chair according to claim 9 wherein the hollow seat includes two apertures defined therein each located within one of the cavities, and each of the armrests includes an insert extending from the lower end into the aperture located within one of the recesses.

11. The chair according to claim 1 wherein the lower block includes a base for installment on the ground and a post mounted on the base.

12. The chair according to claim 11 wherein the post is telescopic.

13. The chair according to claim 12 wherein the lower block includes a control device connected with the telescopic post for control over the extending and shrinking of the telescopic post.