Lifting device for chair including force distributing pressing and locking sleeves
OwnerPo-Chuan Tsaiinventor
Life of this patent
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Abstract
A lifting device for a chair includes an upright support post, a tapered locking sleeve adjustably mounted on the support post, a tapered pressing sleeve mounted on the locking sleeve, a stepping ring having a mounting tube which is mounted on the pressing sleeve, and a dustproof cover abutting a top of the mounting tube of the stepping ring and secured on a top of the pressing sleeve. Thus, the pressing sleeve surrounds the locking sleeve to distribute the pressing force evenly, and the locking sleeve surrounds the support post to distribute the pressing force evenly so as to prevent the pressing sleeve and the locking sleeve from being worn out or broken due to a stress concentration and to enhance the lifetime of the lifting device.
Claims18
A lifting device for a chair comprising:
- an upright support post;
- a tapered locking sleeve adjustably mounted on the support post;
- a tapered pressing sleeve mounted on the locking sleeve;
- a stepping ring having a mounting tube which is mounted on the pressing sleeve;
- and
- a cover abutting a top of the mounting tube of the stepping ring and secured on a top of the pressing sleeve, wherein:
- the locking sleeve has an upper end provided with an outer threaded portion;
- and
- the pressing sleeve has an inner wall having an upper end provided with an inner threaded portion screwed onto the outer threaded portion of the locking sleeve.
A lifting device for a chair comprising:
- an upright support post;
- a tapered locking sleeve adjustably mounted on the support post;
- a tapered pressing sleeve mounted on the locking sleeve;
- a stepping ring having a mounting tube which is mounted on the pressing sleeve;
- and
- a cover abutting a top of the mounting tube of the stepping ring and secured on a top of the pressing sleeve, wherein:
- the pressing sleeve has a bottom provided with an enlarged stop flange to stop the mounting tube of the stepping ring;
- and
- the mounting tube of the stepping ring is located between the cover and the stop flange of the pressing sleeve.
Dependencies are inferred from the claim text.