A power device for driving the rotation of a projection lens barrel

Abstract

The present invention provides a power device for driving the rotation of a projection lens barrel, which includes a projection rotation device, a coupling rubber wheel, a planetary gear reduction box with a planetary gear set inside, a pulley, a DC motor, a transmission structure fixing bracket, a first installation groove and a second installation groove respectively for installing the planetary gear reduction box and the DC motor, a belt, a pulley fixing bracket, a third installation groove for installing the pulley fixing bracket, a pulley central shaft, an automatic clearance adjustment device and a channel provided inside the transmission structure fixing bracket for installing the automatic clearance adjustment device. The power device for driving the rotation of the projection lens barrel provided by the present invention solves the problems that the current reduction motor has a relatively long overall length because the motor and the planetary gear set are mostly directly axially connected together, and the reduction motor has a large noise because it mainly relies on gear meshing to transmit energy during the entire energy transmission process.

Description

Technical Field

[0001] The present invention relates to the technical field of power devices, and particularly to a power device for driving the rotation of a projection lens barrel. Background Art

[0002] At present, projection lamps applied to automobiles on the market usually have two projection effects: one is to project a static pattern through a fixed lens; the other is to install a permanent magnet synchronous motor (such as a 220v AC low-speed permanent magnet motor), and drive a lens rotating part to rotate through a transmission mechanism such as a belt to project a dynamic pattern.

[0003] However, it is found in practice that since most of the patterns projected through fixed lenses are only static patterns, they generally have the disadvantages of monotonous patterns and lack of beauty; and common speed reduction motors on the market, such as the m10 small gear reduction box, mostly directly axially connect the motor and the planetary gear set together, which easily leads to a longer overall length of the speed reduction motor, that is, the length is equal to the height of the motor plus the height of the reduction box, and in the whole energy transmission process of the speed reduction motor, most of the energy is mainly transmitted by the meshing of gears with each other, so the noise is generally large.

[0004] Therefore, it is necessary to provide a power device for driving the rotation of a projection lens barrel to solve the above technical problems. Summary of the Invention

[0005] The main technical problem solved by the present invention is to provide a power device for driving the rotation of a projection lens barrel, which solves the problem that the overall length of the current speed reduction motor is relatively long due to the direct axial connection of the motor and the planetary gear set, and the problem that the speed reduction motor has a large noise because the energy transmission process mainly relies on the meshing of gears with each other.

[0006] To solve the above technical problems, a technical solution adopted by the present invention is to provide a power device for driving the rotation of a projection lens barrel, including a projection rotation device, a coupling rubber wheel 2, a planetary gear reduction box 3 with a planetary gear set inside, a pulley 4, a DC motor 5, a transmission structure fixing bracket 6, a first mounting groove 13 and a second mounting groove 14 provided on the transmission structure fixing bracket 6 for respectively mounting the planetary gear reduction box 3 and the DC motor 5, a belt 8 for connecting the motor shaft of the DC motor 5 and the pulley 4, a pulley fixing bracket, a third mounting groove 12 provided at the bottom of the transmission structure fixing bracket 6 for mounting the pulley fixing bracket, a pulley central shaft 7 placed in the central groove of the pulley fixing bracket, an automatic clearance adjusting device connected to one end of the pulley fixing bracket, and a channel 20 provided on the transmission structure fixing bracket 6 for mounting the automatic clearance adjusting device; wherein, the pulley 4, the planetary gear reduction box 3 and the coupling rubber wheel 2 are sequentially sleeved on the pulley central shaft 7 and mounted on the pulley fixing bracket, the projection rotation device is tangentially contacted with the coupling rubber wheel 2 at a specified angle, and the pulley 4, the belt 8 and the pulley fixing bracket are placed in the bottom mounting groove 22 of the transmission structure fixing bracket 6.

[0007] Preferably, the automatic clearance adjusting device further includes an adjusting rod 19 and a telescopic spring 21 placed at the end of the adjusting rod 19. The head end of the adjusting rod 19 is connected to one end of the pulley fixing bracket, and the adjusting rod 19 and the telescopic spring 21 are placed inside the channel 20.

[0008] Preferably, the pulley fixing bracket further includes a pulley fixing rod 11 and mounting brackets 10 for fixedly mounting the planetary gear reduction box 3 installed at both ends of the pulley fixing rod 11; wherein, fixing grooves 17 are provided at both ends of the planetary gear reduction box 3, the pulley fixing rod 11 and the fixing grooves 17 are mounted at the bottom of the transmission structure fixing bracket 6 through the third mounting groove 12, a first fastener 16 sequentially passes through the transmission structure fixing bracket 6 and the fixing groove 17 to fix the planetary gear reduction box 3 on the mounting bracket 10 at one end of the pulley fixing rod 11, a second fastener 9 fixes the planetary gear reduction box 3 on the mounting bracket 10 at the other end of the pulley fixing rod 11 through the fixing groove 17, the head end of the adjusting rod 19 is connected to the other end of the pulley fixing rod 11, and the pulley central shaft 7 is mounted in the central groove of the pulley fixing rod 11.

[0009] Preferably, the length of the first fastener 16 is greater than that of the second fastener 9. The first fastener 16 is successively sleeved and connected to the transmission structure fixing bracket 6, the fixing groove 17, and the mounting bracket 10 to form a movable support point of the automatic clearance adjusting device. The other end of the pulley fixing rod 11 is placed in the opening direction of the third mounting groove 12 on the side end of the transmission structure fixing bracket 6.

[0010] Preferably, the projection rotation device is directly driven to rotate by the frictional force generated when the coupling rubber wheel 2 rotates, and the image picture inside the coupling rubber wheel 2 moves relatively rotationally.

[0011] Preferably, the projection rotation device further includes a bearing 15 and a projection lens group barrel 1. The projection lens group barrel 1 is fixed to the inner ring of the bearing 15 of the bearing in a preset fixed manner, and the outer edge of the projection lens group barrel 1 is tangentially contacted with the coupling rubber wheel 2 at a specified angle.

[0012] Preferably, a cross-shaped gear shaft 18 is provided at the top of the planetary gear reduction box 3. A cross-shaped groove meshing with the cross-shaped gear shaft 18 is provided at the bottom end of the coupling rubber wheel 2. The pulley central shaft 7 is successively connected to the coupling rubber wheel 2 through the cross-shaped gear shaft 18 and the cross-shaped groove.

[0013] Preferably, the planetary gear set placed inside the planetary gear reduction box 3 is coaxial with the pulley central shaft 7.

[0014] Preferably, a light source required for projection imaging is provided above the projection lens group barrel 1.

[0015] Preferably, the power device for driving the rotation of the projection lens group barrel further includes a control circuit for controlling the driving, stopping, driving rotation direction, and speed of the DC motor 5.

[0016] The beneficial effects of the present invention are as follows: A power device for driving the rotation of a projection lens group barrel provided by the present invention solves the problems that the overall length of the current reduction motor is relatively long because the motor and the planetary gear set are mostly directly axially connected together, and the noise of the reduction motor is large because the energy is mainly transmitted through the meshing of gears during the entire energy transmission process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic structural diagram of a first preferred embodiment of a power device for driving the rotation of a projection lens group barrel of the present invention;

[0018] Figure 2It is a schematic structural principle diagram of the second preferred embodiment of a power device for driving the rotation of a projection lens barrel according to the present invention;

[0019] Figure 3 is Figure 2 a three-dimensional structure diagram of a power device for driving the rotation of a projection lens barrel shown in the figure;

[0020] Figure 4 is Figure 2 a bottom view of a power device for driving the rotation of a projection lens barrel shown in the figure.

[0021] The component names corresponding to the numerical identifications in the attached drawings of the specification are as follows:

[0022] Projection lens barrel 1; Coupling rubber wheel 2; Planetary gear reducer 3; Pulley 4; DC motor 5; Transmission structure fixing bracket 6; Pulley central shaft 7; Belt 8; Second fastener 9; Mounting bracket 10; Pulley fixing support rod 11; Third mounting groove 12; First mounting groove 13; Second mounting groove 14; Bearing 15; First fastener 16; Fixed groove 17; Cross-shaped gear shaft 18; Adjusting support rod 19;; Channel 20; Telescopic spring 21; Bottom mounting groove 22. Specific embodiments

[0023] The technical solution of the present invention will be described in detail below with reference to the drawings.

[0024] Embodiment 1

[0025] Please refer to Figure 1 , Figure 1 is a schematic structural principle diagram of the first preferred embodiment of a power device for driving the rotation of a projection lens barrel according to the present invention. As Figure 1As shown in the figure, the power device for driving the rotation of the barrel of the projection lens group in this embodiment includes a projection rotation device, a coupling rubber wheel 2, a planetary gear reduction box 3 with a planetary gear set inside, a pulley 4, a DC motor 5, a transmission structure fixing bracket 6, a first mounting groove 13 and a second mounting groove 14 provided on the transmission structure fixing bracket 6 for respectively mounting the planetary gear reduction box 3 and the DC motor 5, a belt 8 for connecting the motor shaft of the DC motor 5 and the pulley 4, a pulley fixing bracket, a third mounting groove 12 provided at the bottom of the transmission structure fixing bracket 6 for mounting the pulley fixing bracket, a pulley central shaft 7 placed in the central groove of the pulley fixing bracket, an automatic clearance adjusting device connected to one end of the pulley fixing bracket, and a channel 20 provided on the transmission structure fixing bracket 6 for mounting the automatic clearance adjusting device; wherein, the pulley 4, the planetary gear reduction box 3 and the coupling rubber wheel 2 are sequentially sleeved on the pulley central shaft 7 and mounted on the pulley fixing bracket, the projection rotation device is in tangential contact with the coupling rubber wheel 2 at a specified angle, and the pulley 4, the belt 8 and the pulley fixing bracket are placed in the bottom mounting groove 22 of the transmission structure fixing bracket 6.

[0026] Preferably, the automatic clearance adjusting device further includes an adjusting support rod 19 and a telescopic spring 21 placed at the end of the adjusting support rod 19. The head end of the adjusting support rod 19 is connected to one end of the pulley fixing bracket, and the adjusting support rod 19 and the telescopic spring 21 are placed inside the channel 20.

[0027] Preferably, the pulley fixing bracket further includes a pulley fixing support rod 11 and mounting brackets 10 installed at both ends of the pulley fixing support rod 11 for fixedly mounting the planetary gear reduction box 3; wherein, fixed grooves 17 are provided at both ends of the planetary gear reduction box 3, the pulley fixing support rod 11 and the fixed grooves 17 are installed at the bottom of the transmission structure fixing bracket 6 through the third mounting groove 12, a first fastener 16 sequentially passes through the transmission structure fixing bracket 6 and the fixed groove 17 to fix the planetary gear reduction box 3 on the mounting bracket 10 at one end of the pulley fixing support rod 11, a second fastener 9 fixes the planetary gear reduction box 3 on the mounting bracket 10 at the other end of the pulley fixing support rod 11 through the fixed groove 17, the head end of the adjusting support rod 19 is connected to the other end of the pulley fixing support rod 11, and the pulley central shaft 7 is installed in the central groove of the pulley fixing support rod 11.

[0028] Preferably, the length of the first fastener 16 is greater than that of the second fastener 9. The first fastener 16 is sequentially sleeved and connected to the transmission structure fixing bracket 6, the fixed groove 17 and the mounting bracket 10 to form a movable support point of the automatic clearance adjusting device. The other end of the pulley fixing support rod 11 is placed in the opening direction of the third mounting groove 12 on the side end of the transmission structure fixing bracket 6; wherein, the automatic clearance adjusting device can cooperate with this movable support point to adjust the friction clearance between the projection rotation device and the coupling rubber wheel 2.

[0029] Preferably, after the coupling rubber wheel 2, the planetary gear reducer 3, the belt pulley 4 and the belt pulley fixing bracket are combined, they can form a new whole. That is, when any one of the coupling rubber wheel 2, the planetary gear reducer 3, the belt pulley 4 and the belt pulley fixing bracket moves, the other components also move relatively.

[0030] Preferably, the projection rotating device is directly driven to rotate by the frictional force generated when the coupling rubber wheel 2 rotates, and the image picture inside the coupling rubber wheel 2 moves relatively rotationally.

[0031] Preferably, the projection rotating device further includes a bearing 15 and a projection lens group barrel 1, which is fixed to the inner ring of the bearing 15 in a preset fixed manner, and the outer edge of the projection lens group barrel 1 is tangent to the coupling rubber wheel 2 at a specified angle.

[0032] In this embodiment, by separately installing the motor of the reduction motor, such as the motor of the m10 small gear reducer, and the planetary reducer, the overall height of the reduction motor can be changed to ensure that the overall height of the reduction motor does not exceed the height of the motor, thereby minimizing the overall height of the reduction motor;

[0033] Moreover, on the basis of not changing the original structure of the reduction motor, such as the m10 small gear reducer, a set of belt pulley transmission devices is added, which can effectively change the speed ratio of the original reduction motor, and at the same time, the belt transmission does not generate noise during gear meshing operation;

[0034] Moreover, the DC motor 5 can directly drive the belt pulley 4 through the belt 8, and then drive the planetary gear set placed inside the planetary gear reducer 3 through the belt pulley central shaft 7 coaxial with the belt pulley 4, thereby driving the planetary gear reducer 3 to drive the coupling rubber wheel 2 to rotate;

[0035] Moreover, the projection lens group barrel 1 is equipped with a projection optical system. After the outer edge of the projection lens group barrel 1 is connected to the outer edge of the coupling rubber wheel 2 at a specified angle, the frictional force generated by the contact between the coupling rubber wheel 2 and the projection lens group barrel 1 during rotation can directly drive the projection lens group barrel 1 to rotate, and the image picture inside the projection lens group barrel 1 moves relatively rotationally. Among them, a rubber ring is provided on the outer ring of the coupling rubber wheel 2;

[0036] Moreover, by implementing the method described in this embodiment, not only can the speed ratio of the reduction motor, such as the m10 small gear reducer, be changed, but also the noise during the operation of the device can be reduced by transmitting energy through the belt. At the same time, the height of the reduction motor, such as the m10 small gear reducer, can be greatly reduced, making the application field of the reducer wider.

[0037] Preferably, the coupling rubber wheel 2, the planetary gear reducer 3, the belt pulley 4, the belt 8, the DC motor 5, the transmission structure fixing bracket 6, the belt pulley central shaft 7 and the automatic clearance adjusting device can form a new reducer;

[0038] Moreover, after the new reducer and the projection rotation device are intersectingly coupled together, when the new reducer drives the coupling rubber wheel 2 to rotate through the belt 8, the frictional force generated with the projection rotation device can directly drive the projection rotation device to rotate, so that the image picture inside the projection rotation device also makes a relative rotational movement;

[0039] Moreover, while the new reducer drives the projection rotation device to rotate, an automatic friction clearance adjuster is provided inside the new reducer. Thus, when the drive component, i.e., the belt pulley central shaft 7 rotates eccentrically during the coupled rotation and friction between the new reducer and the projection rotation device, or when the friction surface between the coupling rubber wheel 2 and the projection lens group barrel 1 is convex or concave, it can be automatically adjusted (and) compensated, effectively avoiding the situation of the device being stuck or idling, so that the coupling rubber wheel 2 is tangent to the projection lens group barrel 1, ensuring the rotational stability and stable friction coefficient of the overall device;

[0040] Moreover, the automatic friction clearance adjuster can have two compensation methods, that is, after the clearance between the coupling rubber wheel 2 and the projection lens group barrel 1 becomes larger, it will automatically control the adjusting rod 19 to shrink inward to reduce the clearance between the coupling rubber wheel 2 and the projection lens group barrel 1, and vice versa, it will automatically control the adjusting rod 19 to extend outward to increase the clearance between the coupling rubber wheel 2 and the projection lens group barrel 1.

[0041] It can be seen that the implementation Figure 1 The described power device for driving the projection lens group barrel to rotate solves the problems that the current reduction motor has a longer overall length because the motor and the planetary gear set are mostly directly axially connected together, and the reduction motor has a large noise because it mainly relies on the meshing of gears to transmit energy during the entire energy transmission process.

[0042] In addition, the implementation Figure 1 The described power device for driving the projection lens group barrel to rotate, by separately installing the motor of the reduction motor, such as the motor of the m10 small gear reducer, and the planetary reducer, can change the overall height of the reduction motor to ensure that the overall height of the reduction motor does not exceed the motor height, thereby minimizing the overall height of the reduction motor to the greatest extent.

[0043] In addition, the implementation Figure 1The described power device for driving the rotation of the projection lens barrel adds a set of pulley transmission devices on the basis of not changing the original structure of the reduction motor, such as the m10 small gear reduction box, and can effectively change the speed ratio of the original reduction motor.

[0044] In addition, implementing Figure 1 The described power device for driving the rotation of the projection lens barrel, by implementing the method described in this embodiment, can not only change the speed ratio of the reduction motor, such as the m10 small gear reduction box, but also reduce the noise during the operation of the device by transmitting energy through the belt. At the same time, it can greatly reduce the height of the reduction motor, such as the m10 small gear reduction box, making the application field of the reduction box wider.

[0045] In addition, implementing Figure 1 The described power device for driving the rotation of the projection lens barrel, through the automatic clearance adjustment device provided at the bottom of the transmission structure fixing bracket, can automatically adjust and compensate when the driving component, that is, the pulley central shaft rotates eccentrically during the coupled rotation friction between the power device and the projection rotation device, or when the friction surface between the coupled rubber wheel and the projection lens barrel is convex or concave. This effectively avoids the situation of the device being blocked or idling, so that the coupled rubber wheel is tangent to the projection lens barrel, ensuring the rotational stability and stable friction coefficient of the overall device.

[0046] Embodiment 2

[0047] Please refer to Figure 2 , Figure 2 which is a schematic structural principle diagram of the second preferred embodiment of a power device for driving the rotation of the projection lens barrel. Among them, Figure 2 The shown power device for driving the rotation of the projection lens barrel is optimized from Figure 1 the shown power device for driving the rotation of the projection lens barrel.

[0048] Compared with Figure 1 the shown power device for driving the rotation of the projection lens barrel, Figure 2 on the top of the planetary gear reduction box 3 of the shown power device for driving the rotation of the projection lens barrel, there is a cross-shaped gear shaft 18. At the bottom end of the coupled rubber wheel 2, there is a cross-shaped groove meshing with the cross-shaped gear shaft 18. The pulley central shaft 7 is connected to the coupled rubber wheel 2 through the cross-shaped gear shaft 18 and the cross-shaped groove in sequence.

[0049] Preferably, after the planetary gear reduction box 3 rotates, the cross-shaped gear shaft 18 placed at the top end of the planetary gear reduction box 3 is clamped with the cross-shaped groove at the bottom end of the coupled rubber wheel 2, and then the cross-shaped gear shaft 18 drives the coupled rubber wheel 2 to rotate.

[0050] Preferably, the planetary gear set disposed inside the planetary gear reducer 3 is coaxial with the center axis of the pulley 7.

[0051] Preferably, a light source required for projection imaging is provided above the barrel 1 of the projection lens group; wherein, the light path direction of the light source can form a predetermined pattern imaging effect through the barrel 1 of the projection lens group..

[0052] Preferably, the power device for driving the rotation of the barrel of the projection lens group further includes a control circuit for controlling the driving, stopping, and driving rotation direction and speed of the DC motor 5.

[0053] It can be seen that implementing Figure 2 the described power device for driving the rotation of the barrel of the projection lens group solves the problems that the current reduction motor has a relatively long overall length because the motor and the planetary gear set are mostly directly axially connected together, and the reduction motor has a large noise because it mainly relies on the meshing of gears to transmit energy during the entire energy transmission process.

[0054] In addition, implementing Figure 2 the described power device for driving the rotation of the barrel of the projection lens group can project many special effects such as active changes, color rendering, and overlapping, which is beneficial to enhancing the attractiveness and effect of advertisements.

[0055] In addition, implementing Figure 2 the described power device for driving the rotation of the barrel of the projection lens group has a simple structure, reasonable design, convenient installation and use. It can automatically adjust the offset when the contact surface between the power device and the projection rotation device is offset to ensure the projection effect, and it has strong inventiveness and is convenient for popularization and use.

[0056] The above are only the embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structure made by using the description and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be included in the patent protection scope of the present invention by the same token.

Claims

1. A power device for driving the rotation of a projection lens barrel, characterized in that: It includes a projection rotation device, a coupling rubber wheel (2), a planetary gear reduction box (3) with a planetary gear set inside, a pulley (4), a DC motor (5), a transmission structure fixing bracket (6), a first mounting groove (13) and a second mounting groove (14) provided on the transmission structure fixing bracket (6) for mounting the planetary gear reduction box (3) and the DC motor (5) respectively, a belt (8) for connecting the motor shaft of the DC motor (5) and the pulley (4), a pulley fixing bracket, a third mounting groove (12) provided at the bottom of the transmission structure fixing bracket (6) for mounting the pulley fixing bracket, a pulley central shaft (7) placed in the central groove of the pulley fixing bracket, an automatic clearance adjustment device connected to one end of the pulley fixing bracket, and a channel (20) provided inside the transmission structure fixing bracket (6) for mounting the automatic clearance adjustment device; wherein, the pulley (4), the planetary gear reduction box (3) and the coupling rubber wheel (2) are sequentially sleeved on the pulley central shaft (7) and mounted on the pulley fixing bracket, the projection rotation device is in tangential contact with the coupling rubber wheel (2) at a specified angle, and the pulley (4), the belt (8) and the pulley fixing bracket are placed in the bottom mounting groove (22) of the transmission structure fixing bracket (6); The automatic clearance adjustment device further includes an adjustment support rod (19) and a telescopic spring (21) placed at the end of the adjustment support rod (19), the first end of the adjustment support rod (19) is connected to one end of the pulley fixing bracket, and the adjustment support rod (19) and the telescopic spring (21) are placed inside the channel (20); The pulley fixing bracket further includes a pulley fixing support rod (11) and mounting brackets (10) installed at both ends of the pulley fixing support rod (11) for fixedly mounting the planetary gear reduction box (3); wherein, fixed grooves (17) are provided at both ends of the planetary gear reduction box (3), the pulley fixing support rod (11) and the fixed grooves (17) are mounted at the bottom of the transmission structure fixing bracket (6) through the third mounting groove (12), a first fastener (16) sequentially passes through the transmission structure fixing bracket (6) and the fixed grooves (17) to fix the planetary gear reduction box (3) on the mounting bracket (10) at one end of the pulley fixing support rod (11), a second fastener (9) fixes the planetary gear reduction box (3) on the mounting bracket (10) at the other end of the pulley fixing support rod (11) through the fixed grooves (17), the first end of the adjustment support rod (19) is connected to the other end of the pulley fixing support rod (11), and the pulley central shaft (7) is installed in the central groove of the pulley fixing support rod (11); The length of the first fastener (16) is greater than that of the second fastener (9). The first fastener (16) is sleeved and connected to the transmission structure fixing bracket (6), the fixing groove (17), and the mounting bracket (10) in sequence to form a movable support point of the automatic clearance adjusting device. The other end of the pulley fixing rod (11) is placed in the opening direction of the third mounting groove (12) on the side end of the transmission structure fixing bracket (6).

2. The power device for driving the rotation of the barrel of the projection lens group according to claim 1, characterized in that: The projection rotation device is directly driven to rotate by the frictional force generated when the coupling rubber wheel (2) rotates, and the image picture inside the projection rotation device rotates relatively.

3. The power device for driving the rotation of the projection lens barrel according to claim 2, wherein: The projection rotation device further includes a bearing (15) and a projection lens barrel (1). The projection lens barrel (1) is fixed to the inner ring of the bearing of the bearing (15) in a preset fixing manner, and the outer edge of the projection lens barrel (1) is in tangential contact with the coupling rubber wheel (2) at a specified angle.

4. The power device for driving the rotation of the projection lens barrel according to claim 3, wherein: A cross-shaped gear shaft (18) is provided at the top of the planetary gear reduction box (3). A cross-shaped groove meshing with the cross-shaped gear shaft (18) is provided at the bottom end of the coupling rubber wheel (2). The pulley central shaft (7) is connected to the coupling rubber wheel (2) through the cross-shaped gear shaft (18) and the cross-shaped groove in sequence.

5. The power device for driving the rotation of the lens barrel of the projection lens group according to claim 4, characterized in that: The planetary gear set placed inside the planetary gear reduction box (3) is coaxial with the pulley central shaft (7).

6. The power device for driving the rotation of the barrel of the projection lens group according to claim 5, wherein: A light source required for projection imaging is provided above the projection lens barrel (1).

7. The power device for driving the rotation of the barrel of the projection lens group according to any one of claims 1 to 6, characterized in that: The power device for driving the rotation of the projection lens barrel further includes a control circuit for controlling the driving, stopping, driving rotation direction, and speed of the DC motor (5).

Images