Please select the most similar patent number from A, B, C and D. Which number is?
A turnover machine for overhauling bearings, comprising a rack (1). The bottom of the rack (1) is provided with wheels (2). The rack (1) is further provided with a first turnover plate (3) and a second turnover plate (4) separately. One end of the first turnover plate (3) and one end of the second turnover plate (4) are both hingedly connected to the rack (1) by means of pin shafts (5.1, 5.2). A first turnover cylinder (601) and a second turnover cylinder (6.2A) are further provided inside the rack (1). The bottom of the other end of the first turnover plate (3) is hingedly connected to an end of a piston rod in the first turnover cylinder (6.1A), and the bottom of the other end of the second turnover plate (4) is hingedly connected to an end of a piston rod in the second turnover cylinder (6.2A). The rack (1) is further provided with conveying rollers (7, 8). The back of the second turnover plate (4) is provided with a support frame (9). A clamping cylinder (10) is provided in the support frame (9). A chuck (11) is further provided in the second turnover plate (4). An end of a piston rod in the clamping cylinder (10) is fixedly connected to the back of the chuck (11), and the front of the chuck (11) is provided a claw (12) and further provided with a guide rail (18). Two sides of the back of the claw (12) are slidably connected to the guide rail (18), and the back is further provided with a lead screw (15). The middle of the back of the claw (12) is fixedly connected to a nut seat sleeved on the lead screw (15). The turnover machine has a variety of turnover angles, can meet the processing requirements of different processes of bearings, can more conveniently and stably fix the bearings, and is less likely to scratch the surfaces of the bearings.
A: A tubular product lifting appliance, comprising a mounting base (1). Lifting rods (2) are fixedly provided on the periphery of the top of the mounting base; a telescopic air cylinder (3) is fixedly provided at the center of the top of the mounting base; an end part of a piston rod in the telescopic air cylinder penetrates through the mounting base to be fixedly connected to one end of a connecting rod (4), and the other end of the connecting rod is fixedly provided with a vacuum chuck (5); the vacuum chuck absorbs a tubular product (12); a first guide rail (6) is fixedly provided at the bottom of the mounting base; a first electric sliding block (7) is slidably provided in the first guide rail; the bottom of the first electric sliding block is fixedly connected to one end of a first L-shaped supporting plate (8), and the other end of the first L-shaped supporting plate is slidably connected to the other end of a second L-shaped supporting plate (10) by means of matching of a sliding groove (9) and a sliding rail (11). The tubular product lifting appliance is provided with the vacuum chuck, the first L-shaped supporting plate, the second L-shaped supporting plate, and a pressing block (16), thereby solving the problem that the conventional tubular product lifting appliance is low in safety and not easy to lift.
B: A conveying device for automatic flipping of bearings. A low conveying belt (15) is provided between a pair of low conveying wheels (14); a high conveying belt (17) is provided between a pair of high conveying wheels (16); a flipping unit (20) comprises upper rotating support plates (22) rotationally provided on the end surfaces, away from each other, of a pair of center vertical plates (11); vertically-disposed clamping support plates (221) are formed at the lower end of a left end surface and the upper end of a right end surface of each upper rotating support plate (22), respectively; vertical moving bases (241) are vertically and movably provided at the ends, away from the upper rotating support plate (22), of the clamping support plates (221); bearing clamping blocks (26) are respectively provided on the end surfaces, close to each other, of a pair of vertical moving bases (241) in a front-back moving mode; an upper connecting plate (111) is formed between the upper ends of the central vertical plates (11); the upper connecting plate (111) is located on the upper side of the high conveying belt (17), and a pushing stop plate (271) is provided on a right end surface of the upper connecting plate (111) in a left-right moving mode.
C: Disclosed is a multi-roller flat plate cylindrical embossing machine, comprising: a rack (1), wherein longitudinal sliding grooves (2) are symmetrically arranged at upper ends of two sides of the rack (1); two sides of a lower end of a mobile frame (3) are respectively arranged in the longitudinal sliding grooves (2) in a sliding manner by means of sliding blocks (4); a first rack (5) is arranged at an upper end of one sliding block (4); a first drive electric motor (6) is arranged in the rack (1); a first gear (8) fitting the first rack (5) is arranged on an electric motor shaft (7) of the first drive electric motor (6); first air cylinders (9) are symmetrically arranged at two sides of an upper end of the mobile frame (3); bearing blocks (11) are respectively arranged on piston rods (10) of the first air cylinders (9); two ends of a cylinder (12) are respectively arranged on the bearing blocks (11) in a rotating manner by means of spindles (13); a second air cylinder (14) is arranged on the mobile frame (3) at one side of one spindle (13); an ejector pin (16) is arranged on a piston rod (15) of the second air cylinder (14); and one spindle (13) is provided with an ejector pin hole (17) fitting the ejector pin (16).
D: A pipe feeding mechanism for a paint spraying pipe labeling machine comprises a machine frame, and a bin (1), a pipe pushing mechanism (2), a pipe detection electric eye (3), a pipe clamping mechanism (4), and a rotating mechanism (6), which are disposed on the machine frame. A pipe conveying groove (9) penetrating the bin (1) and extending rightwards is provided at the bottom of the bin (1). The pipe pushing mechanism (2) comprises a push pin (14), a push pin guide seat (16), and a pipe pushing cylinder (17). The push pin (14) is slidably installed on a linear guide rail (15) via a push pin sliding seat (13), the telescopic end of the pipe pushing cylinder (17) is connected to the push pin sliding seat (13), and the pipe detection electric eye (3) is disposed on the right of the pipe conveying groove (9). The pipe clamping mechanism (4) comprises a pipe clamping head (25) and a clamping pneumatic finger (26), the pipe clamping head (25) being located on the right side of the pipe conveying groove (9). The rotating mechanism (6) comprises a rotating shaft (27), a rotating fixing seat (28), and a rotating cylinder (29). The rotating shaft (27) is installed in the rotating fixing seat (28), the rear end of the rotating shaft is connected to the clamping pneumatic finger (26), the tail of the rotating cylinder (29) is rotatably hinged to the machine frame, and the head of the rotating cylinder is hinged to the rotating shaft (27). The pipe feeding mechanism can automatically complete a one-by-one pipe feeding operation, the labor intensity of workers is reduced, and the working efficiency is high.
Answer: B