JPH04128706A - Zoom lens driving device - Google Patents

Abstract

PURPOSE:To reduce the size and power consumption by transmitting the rotation of two-phase driving parts, composed of two motors, whose rotors are varied 90 deg. in magnetizing direction, to screws through speed reducing mechanisms and moving a variator lens group or compensator lens group by moving frames which are engaged. CONSTITUTION:The rotation of the two-phase driving parts 121 - 128 and 151 - 154 composed of the two motors whose rotors 111 - 114 operate with mutually 90 deg. out-of-phase currents supplied from a commutation circuit 200 and are 90 deg. different in magnetizing direction is transmitted to the screws 192 and 194 through the speed reducing mechanisms 170 and 180. The variator lens group or compensator lens group is moved by the moving frames 195 and 197 which engages the screws 192 and 194. Consequently, the zoom lens driving device is reduced in size, reduced in load since a cam ring sliding in a lens barrel is not necessary, and small in power consumption.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a zoom lens driving device for moving a variator lens group or a compensator lens group of an electric zoom lens.

[Conventional technology]

FIG. 16 is a sectional view showing a conventional zoom lens driving device;
FIG. 17 is a partially cutaway front view thereof, and FIG. 18 is an explanatory diagram showing the cam mechanism. In the figure, 10 is a convex lens 1
1 and 12, a focus lens group consisting of a focus ring 13, and a front group frame 15 with screws 14 cut therein; 20, a screw 21 screwed into the screw 14 of the front group frame 15; and a sliding part 22; It is a lens barrel having the following. Reference numeral 30 denotes a variator lens group in which concave lenses 32 and 33 are incorporated in the movable frame 31, and 40 is a compensator lens group in which a negative meniscus lens 42 is incorporated in the movable frame 41. 50 incorporates a convex lens 52 into a lens frame 51, and a convex lens 54 and a concave lens 5 into a lens frame 53 inserted into the lens frame 51.
5. This is a relay lens group incorporating convex lenses 56, 57 and concave lenses 58. 61 is the lens barrel 20 and the front group frame 15 of the focus lens group 10
62 is the lens barrel 20 and the relay lens group 5.
It is a disc sandwiched between the lens frame 51 of 0 and 63 to 65.
is a column fixed to these disks 61 and 62. 70
A cam ring is disposed within the lens barrel 20 and includes a variator cam 71 and a compensator cam 72, and 73 is a bottle inserted into the cam ring 70. The movable frame 31 of the variator lens group 30 includes a support 6.
Grooves 34 and holes 35 and 36 are provided in which the cams 3 to 65 engage, and a protrusion 37 that engages with the variator cam 71 is implanted on the outer periphery thereof. Similarly, the movable frame 41 of the compensator lens group 40 is provided with grooves 43 and holes 44 and 45 in which the supports 63 to 65 engage, and a protrusion 46 that engages with the compensator cam 72 is planted on the outer periphery of the groove 43 and holes 44 and 45, respectively. It's included. Further, 81 is a geared motor, 82 is its shaft, and 8
3 is a small gear attached to the shaft 82. 90 is a ring which is fitted into the sliding part 22 of the lens barrel 20 and has a tooth part 91 on its outer periphery that meshes with the small gear 83; 92 is a ring with which the pin 73 implanted in the cam ring 70 is engaged; This is a groove provided in a part of this circular ring 90 that fits together. Next, the operation will be explained. When the geared motor 81 rotates, a ring 90 having teeth 91 meshing with the small gear 83 rotates. Since the ring 90 and the cam ring 70 are connected through the pin 73, the cam ring 70 also rotates as a unit as the ring 90 rotates. As a result, when the geared motor 81 rotates in the direction shown by the arrow CW in FIG. 17, the cam ring 70 rotates in the direction shown by the arrow C-CW in FIG. 18. Due to this rotation, the protrusion 37 implanted in the moving frame 31 of the variator lens group 30 moves along the variator cam 71, and the variator lens group 30
The moving frame 31 moves in the direction shown by the arrow WIDE in FIG. 18 using the support 65 as a guide. At this time, the protrusion 46 of the compensator lens group 40, which is implanted in the movable frame 41, is engaged with the compensator cam 72, so that the compensator lens group 40 acts to correct the image point shift accompanying the zooming. On the other hand, the geared motor 81 is indicated by arrows C and C-W in FIG.
When rotating in the direction shown, the cam ring 70 rotates in the first direction.
Rotate in the direction of arrow C-W in Figure 8, and variator lens group 3
0 moves in the direction of the force indicated by the arrow device E in FIG. In this case as well, the compensator lens group 40 is moved by the action of the compensator cam 72 so as to correct the movement of the image point due to zooming.

[Problem B that the invention attempts to solve]

Since the conventional zoom lens drive device is configured as described above, not only does the guard motor 81 protrude outside the lens barrel 20 and become an obstacle to miniaturization, but also the guard motor 81 moves the cam ring 70 inside the lens barrel 20. By sliding and rotating, the variator lens group 30 and the compensator lens group 40
Since the movement of the geared motor 81 is controlled, there is a limit to reducing the load, and there are problems such as increased power consumption of the geared motor 81. The inventions set forth in claims (1) and (2) have been made to solve the above-mentioned problems, and their purpose is to obtain a zoom lens drive device that is compact and consumes little power.

[Means to solve the problem]

The zoom lens driving device according to the invention described in claim (1) includes a rotor made of a permanent magnet whose cylindrical surface is magnetized, a stator that generates a rotating magnetic field around the rotor, and a stator that excites the stator. A two-phase drive unit consisting of excitation windings is fitted to the rotating shaft so that the magnetization directions of the respective rotors are shifted by 90 degrees from each other, and currents having a phase difference of 90 degrees are supplied to the excitation windings of each phase. A commutation circuit that is equipped with a deceleration mechanism attached to its rotating shaft, a screw that is rotationally driven by the deceleration mechanism, and a moving frame that is screwed onto the screw to move the variator lens group or compensator lens group. It is. Further, the zoom lens driving device according to the invention described in claim (2) includes a rotor made of a permanent magnet whose cylindrical surface is magnetized, a stator that generates a rotating magnetic field around the rotor, and an excitation of the stator. an excitation winding, a commutator in which commutator pieces each made of a cylindrical conductor having a semicircular cutout are combined with each other via an insulator, and each is connected to the excitation winding and a power source, and A two-phase drive unit consisting of a black wire that contacts the cylindrical surface of each commutator piece and controls the direction of the current flowing through the excitation winding is operated so that the magnetization direction of each rotor is 90°.
A speed reduction mechanism that is fitted onto a rotating shaft so as to be offset, a screw that is rotationally driven by the speed reduction mechanism, and a movement that moves the variator lens group or compensator lens group by screwing into the screw. It has a frame.

[Effect]

The zoom lens driving device according to the invention according to claim (1) is provided with two motors whose rotors have magnetization directions shifted by 90 degrees and are operated by currents supplied from a commutation circuit and whose phases are shifted by 90 degrees from each other. The rotation of the two-phase drive unit is transmitted to a screw via a speed reduction mechanism, and the variator lens group or compensator lens group is moved by a moving frame screwed onto the screw, thereby creating a compact zoom lens drive device with low power consumption. Realize. In addition, the zoom lens drive device according to the invention described in claim (2) controls the rotation of the two-phase drive unit by the two DC motors whose rotors are magnetized by 90° to the screw through the speed reduction mechanism. By moving the variator lens group or the compensator lens group using a moving frame screwed onto this screw, a compact zoom lens drive device with low power consumption is realized.

【Example】

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing one embodiment of the invention as claimed in claim (1), FIG. 2 is a front view thereof, and FIG.
4 is a sectional view taken along the line A-A taken at the position indicated by -A, FIG. 4 is a sectional view taken along the same <B-B line, and FIG. 5 is a configuration diagram of the drive unit as seen from the direction of arrow C in FIG. 3. In the figure, reference numerals 101 and 102 are rings made of soft magnetic material and fitted into the inner wall of the lens barrel 20 of the electric zoom lens shown in FIG. 111 to 114 are rotors made of permanent magnets whose cylindrical surfaces are magnetized with two poles, and 115 is a rotor with a rotor 111 as a first phase rotor and a rotor 112 as a second phase rotor. Rotating shafts are fitted and fixed with their magnetization directions shifted by 90°, the rotor 113 is the first phase rotor, 114 is the second phase rotor, and the magnetization directions are set by 90°.
It is a rotating shaft that is fitted and fixed with a degree of displacement. 121.122 is a magnetic pole piece forming a first phase stator that generates a rotating magnetic field around the rotor 111; 123.12
4 is a magnetic pole piece forming a second phase stator that generates a rotating magnetic field around the rotor 112, and 125 and 126 are rotor 1
Magnetic pole pieces 127 and 128 form the stator of the first phase that generates a rotating magnetic field around the rotor 114, respectively. Made of soft magnetic material. 131-134 are magnetic pole pieces 121. 123. This is a magnetic core coupled with 125 or 127. 141 is magnetic core 1
31 and 132 are connected to the yoke, 142 is the pole piece 12
2 and 124; 143 is a yoke coupled to magnetic cores 133 and 134; 144 is a yoke coupled to magnetic pole pieces 126 and 1;
28, and are arranged in close contact with the rings 101 and 102, respectively. 145 and 146 are yokes disposed in close contact with the yokes 141 and 142;
7°148 is a yoke disposed in close contact with yokes 143 and 144. These magnetic cores 131 to 134 and the yoke 14
1 to 148 are made of a soft magnetic material, and the ring 101
, 102 act as a stator magnetic circuit composed of magnetic pole pieces 121 to 128. 151.153 is a first phase excitation winding that excites the first phase stator wound around the magnetic core 131 or 133;
Reference numerals 152 and 154 indicate second-phase excitation windings that excite the second-phase stator wound around the magnetic core 132 or 134. 161 is a permanent magnet 111 as a rotor, and a magnetic pole piece 121°12
2 is a stator, and the stator's magnetic circuit and excitation winding 15
1, the first phase drive unit of the compensator lens group consisting of
, 124 as a stator, the second compensator lens group is composed of a magnetic circuit of the stator and an excitation winding 152.
163 is a phase drive unit, and 163 connects the permanent magnet 113 to the rotor.
The magnetic pole pieces 125 and 126 are used as stators, and the first phase drive section of the variator lens group is composed of the magnetic circuit of the stator and the excitation winding 153. The permanent magnet 114 is used as the rotor, and the magnetic pole pieces 127. A stator 128 is a second phase driving section of a variator lens group composed of a magnetic circuit of the stator and an excitation winding 154. 171 is a rotating shaft 1 fitted with permanent magnets 111 and 112.
15 is a small gear fixed to the small gear 15, 172 is a large gear that meshes with this small gear 171, 173 is a small gear integrally formed coaxially with this large gear 172, 174 is a large gear that meshes with this small gear 173, 175 is this large gear A small gear 176 integrally formed coaxially with the gear 174 is a large gear that meshes with the small gear 175, and these constitute a speed reduction mechanism 170 on the compensator side. 181 is a rotating shaft 1 to which permanent magnets 113 and 114 are fitted.
182 is a large gear that meshes with this small gear 181; 183 is a small gear integrally formed coaxially with this large gear 182; 184 is a large gear that meshes with this small gear 183; 185 is a large gear that meshes with this small gear 183; A small gear 186 integrally formed coaxially with the gear 184 is a large gear that meshes with the small gear 185, and these constitute a deceleration mechanism 180 on the variator side. 191 is the large gear 1 of the reduction mechanism 170 on the compensator side
76 is a rotating shaft fixed to the rotating shaft 1, and 192 is this rotating shaft 1.
This is a screw that is coaxial with 91. 193 is a rotating shaft fixed to the large gear 186 on the variator side, and 194 is a screw coaxial with this rotating shaft 193. 195 is a compensator lens group 40.
196 is a screw hole of the moving frame 195 into which the screw 192 is screwed. 197 is a moving frame attached to the variator lens group 30;
8 is a screw hole of the moving frame 197 into which the screw 194 is screwed. These moving frames 195, 197 are engaged with the support columns 63,
Groove 199 that guides them in the optical axis direction of the zoom lens
is provided. FIG. 6 is a circuit diagram showing a commutation circuit that supplies drive current to each of the excitation windings 151 to 154. 200 is the commutation circuit, and switching transistors 201 to 204 connect the first phase excitation winding 151 or 1.
The drive current of 53 is passed through the switching transistors 205 to 205.
At 208, the drive current of the second phase excitation winding 152 or 154 is controlled to supply drive currents having a phase difference of 90° to the excitation windings of each phase. Next, the operation will be explained. Magnetic flux φ generated from the N pole of the permanent magnet 111 shown in FIG.
, is empty! 1211-Pole piece 121-Magnetic core 131-Yoke 1
41, and is divided into halves by the yoke 141 to form a circular ring 102,
The flow is divided into the yoke 145 and merged with the yoke 142 to form the magnetic pole piece 12.
2. It passes through the air gap 212 and returns to the S pole of the permanent magnet 111. Here, the torque acting between the excitation winding 151 of the first phase drive unit 161 of the compensator lens group 40 and the permanent magnet 111 is calculated. First, the magnetic flux linkage number φA (θ) of the excitation winding 151 is expressed by the following equation. φA(θ) = 2CO5θ (1) -' where N is the number of turns of the excitation winding 151, 2a is the permanent magnet 111
Dr is the diameter of the permanent magnet 111, Bm is the maximum value of the air gap magnetic flux density, θ1 is an arbitrary point on the permanent magnet 111, θ
is the rotation angle. Therefore, the torque τA (t) acting on the permanent magnet 111 is r A (t) = Kz sin
ωt-1A(t) (2). Through a similar derivation process, the torque acting on the second phase drive section 162 of the compensator lens group 40 is
The magnetization direction of the permanent magnet 1 of the first phase drive section 161 is
Since it is 90a different from the magnetization direction of No. 11, rll(t) = Kz cos ωt-L+ (t
) (3) becomes. The torque of the first phase drive section 161 shown in equation (2) is shown in FIG. 9(a), and the torque of the second phase drive section 162 shown in equation (3) is shown in FIG. As can be seen from the figure, the pulsations of both cancel each other out. Furthermore, in FIG. 6, when the switching transistors 201 and 204 that control the drive current of the first phase are turned on, a DC voltage ■ is applied to the excitation winding 151, and a current in the positive direction shown by the arrow flows. , switching transistor 2
When 02 and 203 are turned on, a current flows in the excitation winding 151 in the negative direction opposite to the arrow. The voltage applied to the excitation winding 151 is a rectangular wave, but if we consider only the basic distribution,
It becomes a sine wave. The mechanism by which current flows through the excitation winding wA152 of the second phase also differs from that of the first phase.
The same is true for phases. Since there is a temporal phase difference of 90° between the interlinkage magnetic flux of the first phase and that of the second phase, the current flowing through the excitation windings 151 and 152 by the commutation circuit 200 in FIG. By controlling the on/off timing of the magnets 209 to 209 so as to give a phase difference of 90 degrees, the torque shown in FIG. 9 is obtained, and the rotor formed by the permanent magnets 111 and 112 continues to rotate. The rotational force of this rotor is generated by the small gear 1 fitted on the rotating shaft 115.
71 to a large gear 172 meshing with it, a small gear 173 integrated therewith to a large gear 174, and a small gear 175 integrated therewith to a large gear 176. This large gear 176 has a rotating shaft 1 coaxial with the screw 192.
91, and this screw 192 is screwed into the screw hole 196 of the moving frame 195 of the compensator lens group 40, so that the first phase and second phase drive parts 161°16
2 operates, the compensator lens group 40 moves back and forth in accordance with the movement of the moving frame 195. The structure and operation of the drive device for moving the variator lens group 30 are also exactly the same as the drive device for the compensator lens group 40. The rotational force of the small gear 181 fitted to the rotating shaft 116 coupled to the rotor of each phase is transmitted to the reduction mechanism 1
80 gears 182 to 185 to the large gear 186, and further transmitted from the rotation shaft 193 to the screw 194,
When the screw hole 198 is screwed into the screw 194, the moving frame 197 of the variator lens group 30 is moved back and forth. FIG. 10 is a plan view showing an embodiment of the invention as set forth in claim (2), and FIG. 11 is a configuration diagram of the driving section similar to FIG. 5.
The same parts as in FIGS. 1 to 5 are given the same reference numerals to avoid redundant explanation. In the figure, 221 and 223 are first phase commutators that are fitted and fixed to the rotating shaft 115 or 116 and rotate together with the rotor;
4 is a second phase commutator which is also fitted and fixed to the rotor 115 or 116. Further, 231 and 233 are in contact with the first phase commutator 221 or 223, and the first
The black of the first phase controls the direction of the current flowing in the excitation winding 151 or 153 of the phase, and 232 and 234 also contact the commutator 222 or 224 of the second phase to control the direction of the current flowing in the excitation winding 152 of the second phase. Alternatively, it is a second phase black that controls the direction of the current flowing through 154. Here, FIGS. 12 and 13 show each commutator 221 to 2.
24 and each black 231 to 234, FIG. 12 corresponds to the case where the rotation angle θ is 90°, and FIG. 13 corresponds to the case where θ is 270°. . As shown in the figure, each of the commutators 221 to 224 has two commutator pieces 225 and 226 made of a cylindrical conductor having a semicircular cutout, which are combined with each other at the cutout via an insulator 227. It is formed by Further, each of the blacks 231 to 234 is connected to each of the excitation windings 151 to 154 and a DC power supply, and is in contact with the cylindrical surface of each of the commutator pieces 225 and 226, two each, to connect each of the excitation windings. It is composed of four brush pieces 235 to 238 that control the direction of the drive current flowing through the brushes 151 to 154, and an insulating bushing 239 that insulates and supports them. Next, the operation will be explained. Here, FIG. 14 is an explanatory diagram for explaining the operation of the driving section, and FIG. 15 is an explanatory diagram showing the function of the commutator and the black.
is in the position shown in FIG. 14(a), the commutator piece 22
The relative positions of 5, 226 and the plush pieces 235 to 238 are as shown in FIG. 15(a). Therefore, an excitation current flows through the excitation winding 151 in the direction shown in FIG. 14(a), and the magnetic pole piece 121 is magnetized to the north pole, and the magnetic pole piece 122 is magnetized to the south pole. However, in this state, torque does not work. Here, since the permanent magnets 111 and 112 have a phase difference of π/2, the torque from the permanent magnet 112 acts and rotates in the directions shown by arrows C and W in FIG. 14(a). When this rotation progresses a little, each commutator piece 225, 2
26 and each of the brush pieces 235 to 238 are as shown in FIG. 15(b), and the permanent magnet 111 is rotated to the position shown in FIG. 14 et al. Commutator 22 at this time
The rotational position of No. 1 is shown in FIG. As the rotation progresses further, the relative positions of the commutator pieces 225, 226 and the brush pieces 235 to 238 become as shown in FIG. 15(C), the permanent magnet 111 rotates to the position shown in FIG. 14(C), and finally , as shown in FIG. 15(d) and FIG. 14(d). At this time, the rotational position of the commutator 221 becomes the position shown in FIG. Moreover, the permanent magnet 112 is 11
It is fitted and fixed to the same rotating shaft 115 as 1, and all (
It behaves similarly. In this way, when the permanent magnets 111 and 112 rotate, the rotation is decelerated by the speed reduction mechanism 170 (on the compensator side) and transmitted to the rotating shaft 191, and as the screw 192 rotates as the rotating shaft 191 rotates, The moving frame 195 moves back and forth. This is exactly the same on the variator side, and as the permanent magnets 113 and 114 rotate, the moving frame 197 on the variator side moves back and forth. In the above embodiment, the case where the yokes 145 and 146 were provided to form a magnetic circuit was explained, but the yokes 145 and 146 may be omitted, and the speed reduction mechanisms 170 and 180 are also geared. For example, a belt or the like may be used, and in either case, the same effects as in the above embodiment can be achieved.

【Effect of the invention】

As described above, according to the invention set forth in claim (1), two rotors whose magnetization directions are shifted by 90 degrees, which are actuated by currents supplied from a commutation circuit and whose phases are shifted by 90 degrees from each other, are provided. The rotation of the two-phase drive unit by the motor is transmitted to the screw through a speed reduction mechanism, and the variator lens group or compensator lens group is moved by the moving frame screwed onto this screw, allowing for significant downsizing. In addition, a cam ring that slides inside the lens barrel is not required, which reduces the load and provides a zoom lens drive device that consumes less power. Further, according to the invention described in claim (2), the rotation of the two-phase drive unit by the two DC motors whose rotor magnetizing force directions are shifted by 90 degrees is transmitted to the screw via the speed reduction mechanism. Since the variator lens group or convencator lens group is moved by a moving frame screwed onto a screw, it is possible to significantly reduce the size of the lens, and also eliminates the need for a cam ring that slides inside the lens barrel, reducing load. This has the effect of providing a zoom lens driving device with reduced power consumption and reduced power consumption.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a zoom lens driving device according to an embodiment of the invention as set forth in claim (1), FIG. 2 is a front view thereof, FIG. The diagram is B-
A sectional view taken along line B, FIG. 5 is a configuration diagram of the drive section, FIG. 6 is a circuit diagram showing the commutation circuit, FIGS. 7 and 8 are explanatory diagrams of the operation of the drive section, and FIG. 9 is its torque. FIG. 10 is a plan view showing an embodiment of the invention according to claim (2), FIG. 11 is a configuration diagram of the drive section, and FIGS. 12 and 13 are commutator diagrams. Fig. 14 is an explanatory drawing showing the structure of the drive unit, Fig. 15 is an explanatory drawing showing the function of the commutator, Fig. 16 is a sectional view showing a conventional zoom lens driving device, FIG. 17 is a partially cutaway front view, and FIG. 18 is an explanatory diagram of the operation of the cam mechanism. 111.113 is the first phase rotor (permanent magnet), 112
．． 114 is the second phase rotor (permanent magnet), 115.11
6 is the rotation axis, 12L 122, 125° 126 is the first
Phase stator (magnetic pole piece), 123°124.127,12
8 is the second phase stator (magnetic pole piece), 151 and 153 are the first
Phase excitation winding, 152° 154 is the second phase excitation winding, 1
70, 180 are reduction mechanisms, 192, 194 are screws, 19
5. 197 is a moving frame, 200 is a commutation circuit, 221, 22
3 is a first phase commutator, 222 and 224 are second phase commutators, 225 and 226 are commutator pieces, 227 is an insulator, and 231
．． 233 is the first phase black, and 232°4 is the second phase black. In addition, the same symbols in the figures indicate the same or equivalent parts.

Claims (2)

[Claims] (1) A first phase rotor that is fitted onto a rotating shaft and is made of a permanent magnet whose cylindrical surface is magnetized; and a first phase that is arranged around the first phase rotor and generates a rotating magnetic field. a stator, a first-phase excitation winding that excites the first-phase stator, and a first-phase excitation winding that is fitted to the rotating shaft so that the cylindrical surface thereof is 90° shifted from the first-phase rotor. a second phase rotor made of magnetized permanent magnets and rotating together with the first phase rotor;
A second phase stator having a symmetrical structure with the phase stator, a second phase excitation winding that excites the second phase stator, and a 90° A commutation circuit that supplies a current having a phase difference of °, a deceleration mechanism attached to the rotating shaft, a screw rotationally driven by the deceleration mechanism, and a variator lens group or a compensator that is screwed onto the screw. A zoom lens drive device including a moving frame that moves a lens group. (2) A first phase rotor that is fitted onto the rotating shaft and is made of a permanent magnet whose cylindrical surface is magnetized, and a first phase that is arranged around the first phase rotor and generates a rotating magnetic field. A stator, a first-phase excitation winding that excites the first-phase stator, and a commutator piece made of a cylindrical conductor having a semicircular notch are connected to each other at the notch through an insulator. a first phase commutator that is combined with each other, is fitted on the rotating shaft and rotates together with the first phase rotor, and is connected to the first phase excitation winding and the power source, respectively, and first phase brushes that contact two cylindrical surfaces of each commutator piece of each phase commutator to control the direction of the current flowing in the first phase excitation winding; and two first phase brushes that are fitted to the rotating shaft. The first phase rotor is made of a permanent magnet whose cylindrical surface is magnetized with a 90° deviation from that of the first phase rotor.
a second phase rotor that rotates together with the phase rotor; a second phase stator that has a symmetrical structure with the first phase stator; and a second phase excitation that excites the second phase stator. a second phase commutator having a structure symmetrical to the first phase commutator;
Each of them is connected to the excitation winding of the second phase and the power supply, and contacts the cylindrical surface of each commutator piece of the second phase commutator, two each, and connects the excitation winding of the second phase to the excitation winding of the second phase. A second phase brush that controls the direction of the flowing current, a deceleration mechanism attached to the rotating shaft, a screw rotationally driven by the deceleration mechanism, and a variator lens group or a compensator lens screwed onto the screw. A zoom lens drive device including a moving frame for moving a group.