A hinge structure includes: a supporting sheet having an unfolded, flattened state and a folded state; at least one first hinge connected to the supporting sheet, the at least one first hinge being configured to drive the supporting sheet to switch between the unfolded, flattened state and the folded state; at least one flattening support including a first support, a second support, and a flattening bracket, the flattening bracket being connected to the first support and the second support, the flattening bracket being connected to the supporting sheet. When the supporting sheet is in the unfolded, flattened state, the first support and the second support interact with each other and generate a force parallel to a plane where the supporting sheet is located, to maintain the supporting sheet in the unfolded, flattened state.

A hinge structure includes: a supporting sheet having an unfolded, flattened state and a folded state; at least one first hinge connected to the supporting sheet, the at least one first hinge being configured to drive the supporting sheet to switch between the unfolded, flattened state and the folded state; at least one flattening support including a first support, a second support, and a flattening bracket, the flattening bracket being connected to the first support and the second support, the flattening bracket being connected to the supporting sheet. When the supporting sheet is in the unfolded, flattened state, the first support and the second support interact with each other and generate a force parallel to a plane where the supporting sheet is located, to maintain the supporting sheet in the unfolded, flattened state.

Provided are a rotary shaft assembly and a lamp. A first connecting base of the rotary shaft assembly is formed with a positioning hole. A second connecting base of the rotary shaft assembly is rotatably connected to the first connecting base. One end of a positioning pin of the rotary shaft assembly is movably connected to the second connecting base. The other end of the positioning pin is configured to enter or exit the positioning hole from a first side of the positioning hole. An unlocking pin of the rotary shaft assembly is configured to enter or exit the positioning hole from a second side of the positioning hole. The unlocking pin is configured to drive the positioning pin to exit the positioning hole when the unlocking pin enters the positioning hole.

Provided are a rotary shaft assembly and a lamp. A first connecting base of the rotary shaft assembly is formed with a positioning hole. A second connecting base of the rotary shaft assembly is rotatably connected to the first connecting base. One end of a positioning pin of the rotary shaft assembly is movably connected to the second connecting base. The other end of the positioning pin is configured to enter or exit the positioning hole from a first side of the positioning hole. An unlocking pin of the rotary shaft assembly is configured to enter or exit the positioning hole from a second side of the positioning hole. The unlocking pin is configured to drive the positioning pin to exit the positioning hole when the unlocking pin enters the positioning hole.

A motion control and lock mechanism for wooden furniture such as a climbing triangle is provided. The lock mechanism provides secure stop against further motion and holds the furniture in the open or closed position. The lock mechanism is easily fabricated with a CNC router while cutting plywood furniture panels.

An adjustable connection joint has a partially shaped spherical member attached to a first member to be adjusted with respect to a second member. A slidable base member slides in a bushing which is attached to the second member. A bolt extends through a washer that spreads a slotted end of the slidable base member against the bushing. Tightening the bolt pulls a locking member against an inside of the partially spherically shaped member and pulls it against a conical cavity on an end of the slidable member. Tightening the bolt concurrently locks the slidable member in the bushing and locks a position of the partially shaped cylindrical member in the conical cavity at the end of the slidable member.

An adjustable mounting apparatus for electronic devices is configured to be adaptable to various support structures, and to facilitate a customized mount orientation for the electronic devices through several degrees of pivot freedom. The mounting apparatus is particularly adaptable to outdoor or industrial environments in which standard support structure modalities may not be available.

A mechanical limiting mechanism comprises a swivel base, a spring arm, a loading part and a reinforcing arm. The spring arm, the swivel base, the reinforcing arm and the loading part constitute a four-bar mechanism, the loading part moves up and down through the rotation of the spring arm, and a limiting is realized through a contact of the spring arm and the reinforcing arm. When the spring arm and the reinforcing arm drive the loading part to move downwards, after the spring arm is abutted against the reinforcing arm, the four-bar linkage mechanism cannot rotate, a mechanical limiting is realized, and the loading part can be prevented from falling. There is no need to add additional parts, and different height changes of the limiting are realized only by adjusting the size of the spring arm and/or the size of the reinforcing arm.

A mechanical limiting mechanism comprises a swivel base, a spring arm, a loading part and a reinforcing arm. The spring arm, the swivel base, the reinforcing arm and the loading part constitute a four-bar mechanism, the loading part moves up and down through the rotation of the spring arm, and a limiting is realized through a contact of the spring arm and the reinforcing arm. When the spring arm and the reinforcing arm drive the loading part to move downwards, after the spring arm is abutted against the reinforcing arm, the four-bar linkage mechanism cannot rotate, a mechanical limiting is realized, and the loading part can be prevented from falling. There is no need to add additional parts, and different height changes of the limiting are realized only by adjusting the size of the spring arm and/or the size of the reinforcing arm.

Hinges for multipurpose golf training aids, and more particularly, long-wearing, durable low-profile hinges for multipurpose golf training aids, and methods for manufacturing such hinges are disclosed.