IP Library › Granted Patent US 12,565,250
Granted Patent B1
US 12,565,250 · App. 19/329,518 · Granted Mar 3, 2026

Locking device for folding cart

Inventor: Wanjuan Zhu (Puning, CN)
B62B3/022B62B2205/20
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Quick Facts
Patent No.
US 12,565,250
App. No.
19/329,518
Granted
Mar 3, 2026
Kind
B1
Abstract

The provided is a locking device for a folding cart, including a button mechanism and a locking member, where the button mechanism includes a movable portion and multiple fixing hooks; the movable portion is slidably disposed on a first panel body of the folding cart; the locking member is connected to a second panel body of the folding cart; the first panel body is hinged to the second panel body; and the movable portion is able to switch between an initial state and a pushed state. When the movable portion is in the initial state, a side panel is effectively locked, and the locked state of the side panel is effectively maintained without user operation. This design improves the stability of the side panel in an unfolded state, preventing the folding cart from self-unlocking during use, and enhancing the stability of the folding cart in an unfolded state.

Claims (25)

1 . A folding cart comprising a locking device, the locking device comprising: a button mechanism and a locking member, wherein

the button mechanism comprises a movable portion and a plurality of fixing hooks disposed on the movable portion; the movable portion is slidably disposed on a first panel body of the folding cart; the locking member is connected to a second panel body of the folding cart; and the first panel body is hinged to the second panel body;

the movable portion is configured to switch between an initial state and a pushed state; when the movable portion is in the initial state, the plurality of fixing hooks are engaged with the locking member, and the first panel body and the second panel body are coplanar, allowing the first panel body and the second panel body of the folding cart to form a rigid side panel; and when the movable portion is in the pushed state, the plurality of fixing hooks move along a sliding direction of the movable portion and disengage from the locking member, allowing the first panel body and the second panel body to rotate relative to each other and fold;

wherein the locking member comprises a fixing plate and a plurality of fixing arms; the fixing plate is connected to the second panel body; and first ends of the plurality of fixing arms are connected to the fixing plate; and

when the movable portion is in the initial state, the plurality of fixing arms are engaged with the plurality of fixing hooks in a one-to-one correspondence, and the plurality of fixing arms abut against the first panel body.

2 . The folding cart comprising the locking device according to claim 1 , wherein second ends of the plurality of fixing arms are connected by a reinforcing member.

3 . The folding cart comprising the locking device according to claim 1 , wherein the first panel body is provided with an elastic member; the elastic member abuts against the movable portion; and the elastic member is configured to drive the movable portion to reset from the pushed state to the initial state.

4 . The folding cart comprising the locking device according to claim 3 , wherein the movable portion is provided with a first restricting portion; and

when the movable portion is in the initial state, the first restricting portion abuts against the first panel body to restrict further movement of the movable portion.

5 . The folding cart comprising the locking device according to claim 3 , wherein the movable portion is provided with a second restricting portion; and

when the movable portion is in the pushed state, the second restricting portion abuts against the first panel body to restrict further movement of the movable portion.

6 . The folding cart comprising the locking device according to claim 1 , wherein the movable portion comprises a sliding plate; the first panel body is provided with a sliding groove; and the sliding plate is slidably connected to the sliding groove.

7 . The folding cart comprising the locking device according to claim 6 , wherein the movable portion further comprises a guide plate; the first panel body is provided with a guide groove; and the guide plate is slidably connected to the guide groove.

8 . A folding cart comprising a locking device, the locking device comprising: a button mechanism and a locking member, wherein

the button mechanism comprises a movable portion and a plurality of fixing hooks disposed on the movable portion; the movable portion is slidably disposed on a first panel body of the folding cart; the locking member is connected to a second panel body of the folding cart; and the first panel body is hinged to the second panel body;

the movable portion is configured to switch between an initial state and a pushed state; when the movable portion is in the initial state, the plurality of fixing hooks are engaged with the locking member, and the first panel body and the second panel body are coplanar, allowing the first panel body and the second panel body of the folding cart to form a rigid side panel; and when the movable portion is in the pushed state, the plurality of fixing hooks move along a sliding direction of the movable portion and disengage from the locking member, allowing the first panel body and the second panel body to rotate relative to each other and fold;

wherein the first panel body is provided with an elastic member; the elastic member abuts against the movable portion; and the elastic member is configured to drive the movable portion to reset from the pushed state to the initial state; and

wherein a fixing hook of the plurality of fixing hooks is connected to the movable portion to form a U-shaped groove; and a top of the fixing hook of the plurality of fixing hooks forms an inclined surface.

9 . A folding cart comprising a locking device, the locking device comprising: a button mechanism and a locking member, wherein

the button mechanism comprises a movable portion and a plurality of fixing hooks disposed on the movable portion; the movable portion is slidably disposed on a first panel body of the folding cart; the locking member is connected to a second panel body of the folding cart; and the first panel body is hinged to the second panel body;

the movable portion is configured to switch between an initial state and a pushed state; when the movable portion is in the initial state, the plurality of fixing hooks are engaged with the locking member, and the first panel body and the second panel body are coplanar, allowing the first panel body and the second panel body of the folding cart to form a rigid side panel; and when the movable portion is in the pushed state, the plurality of fixing hooks move along a sliding direction of the movable portion and disengage from the locking member, allowing the first panel body and the second panel body to rotate relative to each other and fold;

wherein the first panel body is provided with an elastic member; the elastic member abuts against the movable portion; and the elastic member is configured to drive the movable portion to reset from the pushed state to the initial state;

wherein the movable portion is provided with a second restricting portion;

when the movable portion is in the pushed state, the second restricting portion abuts against the first panel body to restrict further movement of the movable portion; and

wherein the button mechanism further comprises a push portion; the push portion is disposed on the second restricting portion; a top surface of the first panel body is provided with a recess; and the push portion is disposed in the recess.

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