Umbrella pole device, electric umbrella and telescopic device

An umbrella pole device, comprising:

• an umbrella head;
• a middle rod, comprising a plurality of casings, wherein the plurality of the casings are pulled apart to form an end-to-end long rod, the casing in an innermost part of the middle rod is an inner casing, the casing in an outermost part of the middle rod is an outer casing, one end of the inner casing is connected to the umbrella head;
• and
• an umbrella pole transmission assembly arranged in the inner casing, wherein the umbrella pole transmission assembly comprises a first transmission tube and a second transmission tube, the first transmission tube is telescopically sleeved with the second transmission tube, one end of the first transmission tube is rotatably connected to the umbrella head, and one of the first transmission tube and the second transmission tube is a rectangular spring, wherein
• when the first transmission tube rotates in a first direction, the second transmission tube moves toward a direction away from the umbrella head to exert a force on the outer casing, and the plurality of casings of the middle rod are pulled apart to form the end-to-end long rod;
• when the first transmission tube rotates in a second direction, the second transmission tube moves towards a direction close to the umbrella head to cancel the force applied on the outer casing, wherein the second direction is opposite to the first direction.