Please select the most similar patent number from A, B, C and D. Which number is?
A rotary engine, comprising a housing having an inner cavity in the shape of a figure of eight, and a casing inner cavity device main rotary shaft (35) and auxiliary rotary shaft (48), the main rotary shaft (35) and the auxiliary rotary shaft (48) performing transmission via transmission gears (23, 24), the main rotary shaft (35) driving recessed main rolling wheels (31, 32) to rotate, the auxiliary rotary shaft (48) driving a first spacer ring (42) and a second spacer ring (43) to rotate, a second rolling wheel (41) being placed between the first spacer ring (42) and the second spacer ring (43), direct transmission not being possible between the second rolling wheel (41) and the auxiliary rotary shaft (48), the outer circle of the second rolling wheel (41) being tangential to the outer circle of the recessed main rolling wheels (31, 32), the recessed main rolling wheels (31, 32) driving the second rolling wheel (41) to rotate when rotating, a third rolling wheel (51) being mounted between the first spacer ring (42) and the second spacer ring (43) via a third shaft (55), the outer circle of the third rolling wheel (51) being tangential to the outer circle of the second rolling wheel (41) and cutting inside a cylinder inner cavity, the third rolling wheel (51) being driven around the second rolling wheel (41) by the first spacer ring (42) and the second spacer ring (43) to rotate in a rolling manner in the casing inner cavity, forming a variable capacitance cavity body with the synchronously rotating main rolling wheels (31, 32), and opening a ventilation port (a) in a timely manner during motion.
A: A rotary piston engine, comprising a housing and a rotor (11). The rotating rotor (11) is disposed inside the housing; the cavity of the rotor (11) is divided into a compression chamber (13) with a changing volume. The outer ring of the housing is provided with several combustion chambers (14) that can rotate around a main shaft (7) of the rotor (11), and any one of the combustion chambers (14) is communicated with the compression chamber (13). The combustion chambers (14) are in transmission connection with the main shaft (7) via a transmission system, and the combustion chambers (14) drive the main shaft (7) to rotate by means of the combustion of compressed gas. The housing comprises an upper cylinder head (8) and a lower cylinder head (9), and a boss (12) of the upper cylinder head (8) is matched with the seam allowance of the lower cylinder head (9). A rotatable piston wheel gear (10) is provided between the upper cylinder head ( 8) and the lower cylinder head (9); evenly distributed support blocks (37) are arranged on the inner ring of the piston wheel gear (10), and the support blocks (37) are in contact with the rolling pair of the boss (12). Cavities enclosed by the boss (12), the lower cylinder head (9) and two adjacent support blocks (37) are combustion chambers (14). The rotary piston engine overcomes the shortcoming of long and narrow combustion chambers in traditional Wankel triangle rotor engine by means of rotating combustion chambers (14), and improves the combustion efficiency of the engine.
B: A caster and a trolley having the caster, the caster comprising: a shell (1) provided with a first rotary shaft for being connected to an external element; an elastic friction element (3) hinged in the shell (1) and partially extending out of the shell (1) to be disposed in the shell (1); and an extrusion element (4) positioned in the shell (1) and used for extruding the friction element (3) so as to deform the friction element (3). The extrusion element (4) is connected with the first rotary shaft, and the extrusion element (4) and the friction element have a non-contact position, a first contact position and a second contact position; when in the first contact position, the first rotary shaft cannot rotate and a rotary wheel (2) can roll; and when in the second contact position, the first rotary shaft cannot rotate and the rotary wheel (2) cannot roll. The trolley further comprises a ground slope detecting unit disposed on a trolley body and a grip force sensing unit disposed on each handle. The trolley can brake itself according to the angle of a slope.
C: An automatic reloading device for a 3D printer, and an automatic reloading method. Said device comprises an extrusion mechanism and a switching mechanism (6); the extrusion mechanism comprises a driving wheel (7), a first driven wheel set (41), a second driven wheel set (51), a first rotating clamp (4), a second rotating clamp (5), and a tension spring (43); one end of each of the first rotating clamp (4) and the second rotating clamp (5) is hinged to a cover body (1), and the other end of each of the first rotating clamp (4) and the second rotating clamp (5) is connected to the tension spring (43); the switching mechanism (6) comprises a switching rod (61) rotatably connected to an extrusion base (12), and a switching handle (62) fixedly connected to the switching rod (61); the end of the first rotating clamp (4) close to the tension spring (43) is fixedly connected to a first limiting column (42), and the end of the second rotating clamp (5) close to the tension spring (43) is fixedly connected to a second limiting column (52); and when the switching handle (62) is in an initial state, two ends of the switching rod (61) respectively abut against the first limiting column (42) and the second limiting column (52), such that the first driven wheel set (41) and the second driven wheel set (52) are both separated from the driving wheel (7). The present device has a high automation degree, increases the working efficiency, and reduces labor costs.
D: A driving device (100) and an inspection device (200). The driving device (100) comprises a chassis (3), a power assembly (4), a first driving wheel (51), a second driving wheel (52), and an elastic member (6); the power assembly (4) comprises a first motor (41), a second motor (42), a first rotating shaft (43), and a second rotating shaft (44); the first motor (41) and the second motor (42) are both disposed below the chassis (3); the upper end of the first rotating shaft (43) is connected to the first motor (41) so that the first motor (41) drives the first rotating shaft (43) to rotate; the upper end of the second rotating shaft (44) is connected to the second motor (42) so that the second motor (42) drives the second rotating shaft (44) to rotate; the first driving wheel (51) is connected to the lower end of the first rotating shaft (43); the second driving wheel (52) is connected to the lower end of the second rotating shaft (44); the elastic member (6) is disposed on the chassis (3), and the elastic member (6) has one end connected to the first rotating shaft (43) and the other end connected to the second rotating shaft (44). The driving device (100) can travel on a horizontally laid track of a fully mechanized mining face, such that unmanned inspection is achieved.
Answer: A