Please select the most similar patent number from A, B, C and D. Which number is?
A three-dimensional rotation demonstration LED lamp holder, comprising a base (1). The top of the base (1) is fixedly connected to a housing (2). The center of the top of the base (1) is fixedly connected to a rotation base (4). The top of the rotation base (4) is rotatably connected to a rotation lamp stand (5). The top of the rotation lamp stand (5) is fixedly connected to a rotating platform (6). A plurality of central LED color lamps (7) corresponding to the rotating platform (6) are mounted in the center of the top of the rotation base (4). A plurality of atmosphere lamps (8) are mounted on an inner side of the top of the housing (2). An outer ring gear (9) is provided at the bottom of an outer wall of the rotating platform (6). One side of an inner wall of the housing (2) is fixedly connected to a mounting bracket (10). According to the three-dimensional rotation demonstration LED lamp holder, by designing a simple rotation demonstration mechanism, the LED lamp holder can support and drive an ornament to rotate at a constant speed, and the overall display effect of the ornament is more attractive by irradiation of LEDs.
A: An aluminum sheet machining apparatus capable of implementing stable clamping and rotation, comprising a base (1). Support posts (2) are fixedly mounted on the left and right sides of the base; a top plate (3) is fixedly mounted between the tops of the opposite sides of the support posts; a machining structure (4) having one end passing through the top plate and extending out of the bottom of the top plate is fixedly mounted at the top of the top plate; a rotating electric motor (5) is fixedly mounted at the top of the base; a coupling (6) is fixedly mounted at the top of the rotating electric motor; a connecting seat (7) is fixedly mounted at the top of the coupling; a workbench (8) is fixedly mounted at the top of the connecting seat; struts (9) are fixedly mounted on the left and right sides of the top of the base; the top of each strut is movably connected to an engagement rod (10) by means of a rotating shaft. The aluminum sheet machining apparatus capable of implementing stable clamping and rotation is simple in overall structure, achieves the purpose that the workbench on the aluminum sheet machining apparatus is rotatable, facilitates machining and punching of aluminum sheets at different parts, improves the machining efficiency and quality of the aluminum sheet, and is convenient to use.
B: A warehouse storage rack label device, comprising a U-shaped element (1) and a label holder (2). A rotating base (3) is fixedly connected to one side of the U-shaped element (1); a round rod (4) is fixedly mounted on the rotating base (3); the label holder (2) has one side fixedly connected to two connection members (5), and the other side provided with an accommodation slot (6); a visual window (7) is fixedly mounted on the accommodation slot (6); an opening (8) communicated with the accommodation slot (6) is formed in the top of the label holder (2); a label card (9) is placed in the accommodation slot (6); a slide groove (10) is formed in the label holder (2); a pressing rod (11) is slidably mounted in the slide groove (10), and works in conjunction with the round rod (4) for adjusting the angle of the label holder (2); two mounting grooves (12) are formed in the other side of the label holder (2); and a disc (13) is rotatably mounted in each of the two mounting grooves (12) for counting goods. The warehouse rack label device facilitates replacement of the label card (9) when in use, and can adjust the fixing angle of the label device according to the height of each layer of a storage rack, such that a worker can check the label card (9), and real-time counting can be performed on the goods on a corresponding storage rack, thereby facilitating checking.
C: A flat cable dynamic stability testing apparatus, belonging to the field of flat cable detection. The apparatus comprises a bottom platform (1), wherein the upper surface of the bottom platform (1) is fixedly connected to a testing platform (2); the top of the testing platform (2) is fixedly connected to a driving machine box (3); the inner bottom wall of the driving machine box (3) is fixedly connected to an electric motor support frame (4); an inner wall of the electric motor support frame (4) is fixedly connected to a driving electric motor (5); an output end of the driving electric motor (5) is connected to a driving gear (6) in a sleeved manner; the top of the driving gear (6) meshes with a driven gear (7); an inner wall of the driven gear (7) is provided with a rotating shaft (8) in an inserted manner; and one end of the rotating shaft (8) is fixedly connected to a rotating seat (9). The apparatus is provided with the driving electric motor (5), the driving gear (6), the driven gear (7), the rotating shaft (8), the rotating seat (9), a front end fixing plate (10), a front end fastening plate (11), a threaded rod (12), a rotating lever (13), an electric push rod (15) and a high-speed camera (17), such that an operator can conveniently obtain the torsional resistance of a flat cable and the maximum torque limit that the flat cable can bear. The design is simple and convenient to operate, and the test result is accurate and highly reliable.
D: A display showcase for sale of electronic terminal devices, comprising a display showcase body (1) and support legs (5). The support legs (5) are arranged at four corners on the outer wall of the bottom of the display showcase body (1); a mounting opening is formed on the outer wall of the bottom of the display showcase body (1), and an electric motor (2) is fixedly connected onto the inner wall of the mounting opening; one end of an output shaft of the electric motor (2) is provided with a rotary disc (3), and hydraulic cylinders (6) distributed equidistantly in an annular configuration are fixedly connected onto the outer wall of the top of the rotary disc (3); one end of a piston of each hydraulic cylinder (6) is provided with a fixing mechanism; a cover mechanism is arranged inside the display showcase body (1). The display showcase allows for simple and convenient fixing and taking of a device to be displayed; in addition, the rotary disc (3) can drive devices to be displayed on a fixing seat (7) to rotate together to achieve 360° omnidirectional display; rollers (4) at the bottom of the rotary disc (3) can ensure the stability during rotation of the rotary disc (3), thereby effectively improving the display effect; and the display showcase cannot be opened from the outside, thereby effectively improving the anti-theft effect of the display showcase.
Answer: D