JPH043286Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an automatic focusing lens barrel for a camera.

Conventionally, some lens barrels of this type include a motor as a drive source for driving a focusing lens and a gear train for transmitting the rotation of this motor to a photographing lens. In such a lens barrel, the noise generated from the meshing of the gears has been reduced by using a material with a high attenuation rate for the gears and the like constituting the gear train.
However, due to vibrations of the motor and secondary excitation of the gear train caused by collisions between the teeth of the gears that reduce the rotation of the motor, the fixed parts and casing may resonate and generate noise, as mentioned above. Merely adopting such materials did not provide sufficient results in noise reduction. Therefore, in order to sufficiently suppress this vibration transmission, it is conceivable to install the motor and gear train on the fixed part through vibration insulating members. However, if the motor and gear are each provided with a vibration insulating member,
The configuration becomes extremely complex due to the large number of constituent elements.

The purpose of the present invention is to solve these drawbacks, to unify the system subject to vibration isolation by configuring the gear train and motor, which can be an excitation source, into one gear train unit. A supporting member provided between the fixed part of the lens barrel and the fixed part of the lens barrel provides vibrational isolation between the two, and a position adjustment member allows the positional relationship with the unit lens barrel to be easily adjusted, preventing noise with a simple configuration. It is an object of the present invention to provide a device for supporting and adjusting the position of an automatic focusing lens barrel, which can both adjust the position.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. 1 to 3 show an embodiment of the present invention. This embodiment is an automatic focusing lens barrel that has a motor that drives a focusing lens and a gear train that is a power transmission mechanism. FIG. 1 is a perspective view of an automatic focusing lens barrel. Second
The figure is an exploded perspective view showing the positional relationship between the gear train unit and the inner cylinder. FIG. 3 shows a sectional view of a fixing part that fixes the gear train unit to the inner cylinder. The casing 1 shown in FIG.
and the second inner cylinder 6. The manual distance ring 2 is rotatably provided in the casing 1. The aperture ring 3 is installed at the rear end of the casing 1. The photographing lens group 4 is installed inside the casing 1. The first inner cylinder 5 shown in FIG.
is installed in the casing 1, and the flange part 5
a, 5e, a convex portion 5b, a convex portion 5c (not shown), a cylindrical portion 5d, and a cut portion 5f. The second inner cylinder 6 is installed in the casing 1 and has a recess 6a and a cutout 6b, and the first inner cylinder 6 has a recess 6a and a cutout 6b such that the cutout 5f and the cutout 6b form a cylindrical hole. The flange portion 5a of the cylinder 5 and the recessed portion 6a fit together.
The motor 7 shown in FIG. 1 is fixed to a base plate 17 by a fixing member (not shown) so as to drive a gear train. The gear 8 is fixed to the tip of the output shaft of the motor 7. large gear 10a of the two-stage spur gear 10,
The small gear 10b is rotatably supported by the shaft 9 and is installed between the substrates 17 and 18. The large gear 12a and the small gear 12b of the two-stage spur gear 12 are rotatably supported on the shaft 11, and are supported by the base plate 17 and the base plate 18.
is installed between. The gear 14 is rotatably supported by the shaft 13 and is installed between the substrates 17 and 18. The clutch mechanism 14a is installed between the gear 14 and the output gear 15. The output gear 15 is rotatably supported by the shaft 13 and meshes with the internal gear 16. A lens driving gear (internal gear) 16 is adapted to drive a focusing lens in the photographing lens group 4 and is disposed at a predetermined position within the casing 1. The modules of the output gear 15 and the internal gear 16 are formed larger than the modules of other spur gears, and the height of the tooth tips is higher. The above-mentioned substrates 17, 18, shafts 9, 11, 13, motor 7, gears 8, 10, 1
2, 14, and 15 constitute a gear train unit. The gear train unit is board 1
7 and the substrate 18 as described above, the shafts 9, 11, 1
3, and these constitute the skeleton of the gear train unit. As shown in FIG. 2, the base plate 17 of the gear train unit has a hollow hole 17a formed sufficiently larger than the diameter of the screw shaft portion 23a (unthreaded cylindrical portion) of the stepped screw 23.
have. The first regulating means is the stepped screw 23
and a hole 17a. Angle members 19 and 26 are fixed to both left and right ends of the gear train unit with screws 20 and 28, respectively. FIG. 3 shows a pair of angle members 19 shown in FIG.
An enlarged view of members around 26 is shown. Note that the numbers in parentheses in FIG. 3 indicate the numbers of the members around the other angle member. Screw 2 to angle members 19 and 26
The hole through which 0 and 28 pass is the stupid hole 1, similar to hole 17a.
9b and 26b are formed into elongated holes extending in the X direction in FIG. The stepped screw 21 shown in FIG. 3 has a screw shaft portion 21a and a screw portion 21b. The position adjustment means are the holes 19b, 26b and the screws 20, 2.
It consists of 8. The vibration insulating member 22 has a cylindrical shape and has a ring-shaped groove 22a along the circumference.
is cut and a hole 22b is made in the direction of the cylinder axis. This vibration insulating member is made of silicone rubber or the like. The angle member 19 has a hole 19a and a blank hole 19b, the inner diameter of the hole 19a is approximately equal to the outer diameter of the groove 22a of the vibration insulating member 22, and the blank hole 19b is larger than the outer diameter of the screw 20. It is formed large enough. Similarly, the stepped screw 29, the angle member 26, and the vibration insulating member 27 are the same as the stepped screw 21, the angle member 19, and the vibration insulating member 27.
It has the same structure as 2. The vibration insulating means is composed of vibration insulating members 22 and 27. The stepped screws 21 and 29 shown in FIG.
27 through the convex portions 5b, 5c of the first inner cylinder 5.
(not shown) and elastically supports the gear train unit. The stepped screw 23, which is the first regulating means, has the screw shaft portion 23a as described above, and the stepped screw 23 has a buffer member 24 on the upper surface of the blank hole 17a and a buffer member 25 on the lower surface. It is screwed into the flange portion 5e of the first inner cylinder 5 through the hole 17a of the base plate 17. The stepped pin 30 above the shaft 13 and the pin portion 3 implanted in the substrate 18
It has 0a. The buffer member 31 has a pin portion 30
a, and is fitted into a cylindrical hole formed by the notch 5f of the first inner cylinder 5 and the notch 6b of the second inner cylinder 6 in a loose fit state. There is. The second regulating means are cylindrical holes 5f, 6
b, stepped pin 30, pin portion 30a, and buffer member 31
It is composed of:

In this embodiment, the support means includes vibration isolation means, a support member, first restriction means, second restriction means, position adjustment means, and the like.

The operation of the automatic focusing lens barrel of this embodiment will be described below. In FIG. 1, the manual focusing ring 2 is used to adjust the focus by manual operation when the clutch mechanism 14a in the gear train is operated by a manual operation member (not shown) to switch the focus adjustment from automatic operation to manual operation. This is what makes it possible. This clutch mechanism transmits the rotation of a gear (not shown) in the gear train that rotates in response to the rotational force of the manual distance ring 2 during manual operation to the output gear 15. This clutch protects the gear train from slipping when attempting to rotate it beyond its infinite mechanical limits. A manual operation member (not shown) disconnects the output gear 15 from the gear (not shown) and connects the output gear 15 and the gear 14, thereby switching to automatic operation. Here, the operation when performing focus alignment automatically will be explained. The motor 7 rotates its output shaft 7a and the gear 8 fixed thereto in a predetermined direction by the output of a circuit not shown in FIG. The rotation of this gear 8 is controlled by a gear 2 which is rotatably supported on a shaft 9.
The rotation is transmitted to the large gear 10a of the stepped spur gear 10, and its rotation is transmitted via the small gear 10b to the large gear 12a of the two-stage spur gear 12, which is rotatably supported on the shaft 11. The signal is transmitted to a gear 14 which is rotatably supported on a shaft 13. By combining gears in this way, the rotational speed of the motor is reduced and transmitted at an appropriate speed. Gear 14 rotating around shaft 13
is connected to the clutch mechanism 14a, and the power from the motor 7 is transmitted to the output gear 15, which rotates the internal gear 16, and the focusing lens in the photographing lens group 4 is controlled by a pin and cam mechanism (not shown). Drive it in the axial direction to the in-focus position. The gear train unit includes stepped screws 21, 29 and vibration insulating members 22, 2.
7 and is elastically supported by the first inner cylinder 5, when a force that moves the entire unit is applied, the vibration insulating member is elastically deformed and the output gear 1
5 and the internal gear 16 (in the direction of the optical axis or in the direction perpendicular to the optical axis) may be misaligned. However, even if such a thing occurs, the stepped screw 23, which is the first regulating means, comes into contact with the blind hole 17a via the buffer members 24 and 25, thereby regulating the movement in the optical axis direction, and the second regulating means The buffer member 31, which is a regulating means, regulates the movement in the direction perpendicular to the optical axis by coming into contact with the wall surface of the cylindrical hole formed by the inner cylinders 5, 6, 5f, 6b. The gears are designed to stay engaged. Furthermore, by increasing the size of the modules of both gears, the engagement of the gears is further prevented.

In this embodiment, the above two safety measures are taken. The value of this module is at least larger than the module of gears 8, 10, 12, and 14 whose center distances are fixed. By combining the gear train and the motor 7 into a unit (gear train unit), it becomes possible to unify the system to be subjected to vibration isolation. Therefore,
By suppressing the transmission of vibration from this one unit to the lens barrel, the vibration and noise of the entire unit can be suppressed with a simple configuration. The means for supporting the gear train unit at this time will be described in detail. The gear train unit is connected to the convex portions 5b and 5c of the first inner cylinder 5.
(not shown) with stepped screws 21, 29 via vibration insulating members 22, 27. In addition, a second cylinder installed on the base plate 18 of the gear train unit is inserted into the cylindrical hole formed by the cutout 5f of the first inner cylinder 5 and the cutout 6b of the second inner cylinder 6. A buffer member 31 serving as a regulating means is fitted. Vibrations caused by vibrations of the motor or collisions between gears of the gear train are absorbed by the gear train unit through the vibration insulating members 22 and 27.
Since it is supported by the inner cylinders 5 and 6 by 9, it is insulated. Moreover, since the inner cylinders 5 and 6 have the photographic lens group 4 inside and are constrained from the inside, the part that supports the gear train unit is
The flange portions a and 5e are avoided, and the convex portions 5b and 5c (not shown) in the cylindrical portion 5d are selected. Therefore, vibrations from the gear train unit are transmitted to the inner cylinder via the vibration insulating member, thereby preventing the generation of noise due to resonance of the inner cylinder. Furthermore, if the gear train unit is directly fixed to the first inner cylinder 5 and the second inner cylinder 6 or brought into contact with the casing 1, the vibration component of the gear train unit which is the vibration source will be absorbed by the first inner cylinder. The natural frequencies of the cylinder 5, the second inner cylinder 6, the casing 1, etc. and the components around them cause the inner cylinders 5, 6, the casing 1, etc. to resonate and generate noise. Therefore, in this embodiment, the above-mentioned gear train unit is provided so as not to come into contact with surrounding members that are likely to resonate, and this unit is supported by interposing vibration insulating members between the first and second inner cylinders 5 and 6. , the entire motor and gear train can be insulated from vibration with a simpler structure than providing vibration insulating members for the motor and each gear.
In this lens barrel, during automatic operation, the built-in focusing lens is driven by the motor 7, and when it reaches a close or infinite position, if the focus is out of focus at that position, the focusing lens is A reversing device is provided for reversing the drive direction. However, when this reversing device fails, the focusing lens collides with the mechanical restricting member and stops, but the motor still attempts to continue driving. Therefore, at this time, a large torque that decelerates the rotation of the motor is generated in the output gear 15, which attempts to largely displace the entire gear train unit with respect to the lens barrel, causing the meshing of the output gear 15 and the internal gear 16 to change. Displaced in the direction of removal. In addition, when the distance ring is detoured during manual operation to reach a close or infinite mechanical limit position, and the distance ring is still rotated in a direction exceeding this limit, the gear train unit is activated via the clutch mechanism. A large load is applied to the In this way, even if the clutch mechanism fails, the unit is likely to change significantly. Furthermore, the unit similarly tends to be displaced by an external impact. The above-mentioned displacement is regulated by the first regulating means and the second regulating means to ensure normal operation.

Next, the first regulating means and the second regulating means will be explained in detail.

The second regulating means is such that when the gear train unit receives an abnormal force in a direction perpendicular to the optical axis direction due to a failure as described above, the buffer member 31 is 6b, but since the buffer member 31 has elasticity, it deforms itself and absorbs the impact force, preventing large displacement of the gear train unit and not transmitting the impact. to prevent it. That is, the buffer member 31, which is the second regulating means, acts effectively against large displacements of the gear train unit when the above-mentioned force is applied, particularly when a force perpendicular to the optical axis direction is applied.
Note that the collision member 31 is inserted into the cylindrical hole under normal operating conditions.
Even when the gear train units are in contact with each other, vibration of the gear train unit is prevented by the presence of the shock member 31. Next, the first regulating means will be described.
The first restriction means is that when the gear train unit receives an abnormal force in the optical axis direction due to the above-mentioned malfunction or when the lens barrel is accidentally hit against a wall or dropped on the floor, the shock absorbing member 24, 25 prevents the substrate 17 from coming into direct contact with the stepped screw 23 or the flange portion 5e, and also restricts the gear train unit from being displaced beyond a certain degree in the optical axis direction. Further, the stepped screw 23 has a screw shaft portion 23a and a substrate 17.
Under normal operating conditions, the blank holes 17a do not come into contact with each other, so vibrations of the gear train unit are not transmitted. And stepped screw 2
3 is screwed into the flange portion 5e of the first inner cylinder 5 with the substrate 17 sandwiched between the buffer members 24 and 25, and like the other stepped screws 21 and 29, vibration is applied to the cylindrical portion 5d. Unlike the insulating members 22, 27 which are screwed in so as to press them appropriately, the stepped screw 23 is screwed into the base plate 17 of the gear train unit so as not to press the buffer members 24, 25. Therefore, the stepped screw 23, which is the first regulating means, regulates a large displacement of the gear train unit when a force in the direction of the optical axis is applied, and the buffer members 24, 25 Normally, vibrations are not transmitted from the unit to the lens barrel.

In this embodiment, the gear train unit is attached to the first inner cylinder 5 via the angle members 19 and 26 with the stepped screw 2.
When installed with 1 and 29, the output gear 15 of the gear train unit and the internal gear (lens drive gear) 1
As described above, the angle members 19 and 26 are located in the hole 19, which is a position adjusting means, so that the position of the gear train unit can be set so that the gear train unit can be properly engaged with the gear train unit 6.
b, 26b, and its stupid holes 19b, 2
The gear train unit can be installed in the proper position using screws 20 and 28 through 6b.

In the automatic focusing lens barrel of this embodiment, vibration insulating members 22, 27 and supporting members 21, 2
9 to support the gear train unit on the inner cylinder to insulate vibrations and thereby prevent the generation of noise. By providing the buffer member 31, when an abnormal force is applied, the gear train unit is prevented from large displacement, and the gears are prevented from disengaging, and the output gear of the gear train unit and the gear train unit are prevented from disengaging under normal operating conditions. The position adjusting means can also determine the position of the gear train unit so that the gear train unit meshes normally with the lens drive gear.

As described above, according to the present invention, while the relay member provided with the vibration insulating member is fixed to the lens barrel by the support member, the relay member and the unit board are moved relative to each other via the adjustment part of the relay member, and the unit is fixed. Since the position of the unit can be adjusted relative to the lens barrel, there is no need to make delicate adjustments such as positioning on vibration-isolated parts, and the unit can be moved freely. The distance between the rotation centers of the gears can be easily adjusted to a predetermined distance, that is, to a position where the gears mesh properly.

Since the vibration insulating section and the position adjustment section are configured separately in this way, each function can be fully exerted.

In addition, many elements that can be used as drive sources have been made into units, and the shape of the units has been devised, so
When fixing the unit to the lens barrel, a vibration insulating member is interposed between the unit and the lens barrel to suppress the transmission of vibrations and reduce noise caused by vibrations, without increasing the size of the lens barrel. can reduce the occurrence of

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention, FIG. 1 is a perspective view of an automatic focusing lens barrel, FIG. 2 is an exploded perspective view of a gear train unit and an inner cylinder, FIG. 3 is a partial cross-sectional view of the angle member and the vibration isolation member. Explanation of symbols of main parts, {7...drive source, 8,
9, 10, 11, 12, 13, 14, 15... power transmission mechanism, 17, 18... board, 15... output gear} (gear train unit), {22, 27...
...Vibration insulation member (vibration insulation means), 21, 29...
...supporting member, 17a, 23...first regulating means,
5f, 6b, 30, 30a, 31... second regulating means, 19b, 20, 26b, 28... position adjusting means} (supporting means).

Claims (1)

[Claims for Utility Model Registration] A focusing lens, a lens driving gear that is rotatably provided at a predetermined position in a lens barrel and drives the focusing lens, and a lens driving gear that uses power from a driving source to drive the lens. An auto-focusing lens barrel comprising a power transmission mechanism having a plurality of gears for transmission to gears, comprising a pair of arc-shaped unit substrates along the shape of the auto-focusing lens barrel, the unit a single unit that holds the drive source and the power transmission mechanism between substrates; and a single unit that holds the drive source and the power transmission mechanism between the substrates; a support means joined to a predetermined position of the focusing lens barrel; and the output gear 1 at an appropriate position in the vertical direction of the shaft 13 supporting the output gear of the power transmission mechanism.
5 and the lens driving gear 16a are adjusted so that the distance between their rotation centers becomes a predetermined distance, and when the unit is supported at a predetermined position of the autofocus lens barrel, (a) relay members 19 and 26 that connect the unit and the autofocus lens barrel; (b) a vibration insulator disposed on the relay member and interposed between the autofocus lens barrel and the relay member to suppress vibration transmission from the unit to the autofocus lens barrel; (c) supporting members 21, 29 for supporting and fixing the relay member at a predetermined position of the autofocus lens barrel via the vibration insulating member; (a) adjustment means 19b provided on the relay member;
26b; (b) fixing means 20, 28 for fixing the relay member and the unit board via the adjusting means of the relay member; (c) the relay member on which the vibration insulating member is disposed; With the member fixed to the automatic focusing lens barrel by the supporting member, the relay member and the unit board are relatively moved through the adjusting means of the relay member to adjust the position of the unit to the automatic focusing lens barrel. 1. A support and position adjustment device for an automatic focusing lens barrel, which is adjustable with respect to the focusing lens barrel.