JP2016206565A - Lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens barrel with simple configurations that can increase the performances at the rotational operation of a ring.SOLUTION: The lens barrel includes: a fixed barrel; a ring member that can rotate around the fixed barrel and has a periodic structure part with a periodic convexo-concave structure in at least one of an inner surface, an outer surface, and an end surface; and a rotation detecting mechanism set in the fixed barrel, the rotation detecting mechanism having a rolling part including an elastic body, and the rolling part being pressed with a predetermined charge amount against the periodic structure part and constantly being in contact with two or more points with the periodic structure part.SELECTED DRAWING: Figure 10

Description

  The present invention relates to a lens barrel, and more particularly to detection of rotation operation of an operation ring of a lens barrel.

  In recent years, as shown in Patent Documents 1 and 2, the operation amount or speed of the operation ring provided in the lens barrel is temporarily converted into an electrical signal, and the optical system provided in the lens barrel is optically converted based on the signal. A system that drives in the axial direction has been realized.

Japanese Patent Laid-Open No. 04-027906 JP 09-197245 A

  As disclosed in Patent Document 2, there is a method of detecting a rotation amount using a mechanical mechanism that presses a rolling portion against an operation ring and transmits a rotational force of the operation ring portion. In this method, the operation ring is provided with a periodic uneven structure so that the contact portion between the operation ring and the rolling portion pressed against the operation ring does not slip. However, such a mechanism has a problem that the operation quality of the operation lens is lowered.

  In view of the above problems, an object of the present invention is to provide a lens barrel having improved quality with a simple configuration.

In order to achieve the above object, the lens barrel of the present invention includes:
A fixed cylinder;
A ring member having a periodic structure portion that is rotatable around the fixed cylinder and has a periodic uneven structure on at least one of an inner peripheral surface, an outer peripheral surface, and an end surface;
A lens barrel provided with a rotation detection mechanism installed in the fixed cylinder,
The rotation detection mechanism has a rolling part including an elastic body,
The rolling part including the elastic body is configured to be in pressure contact with the periodic structure part with a predetermined charge amount and to be always in contact with the periodic structure part at a plurality of two or more points. And

  ADVANTAGE OF THE INVENTION According to this invention, the lens barrel which improved the quality at the time of rotation operation of a ring can be provided.

FIG. 3 is a schematic perspective view showing the lens barrel operation detecting means in the first embodiment. Block diagram for explaining the camera system in the first embodiment Sectional schematic diagram of the lens barrel in the first embodiment The schematic diagram which shows the rotation amount detection means in 1st Example. The perspective view of the cylindrical electrode in 1st Example, and the schematic diagram explaining rotation operation | movement The schematic diagram which shows the signal from the switch at the time of operation ring rotation in 1st Example Electrical circuit diagram of the first embodiment The flowchart showing the control flow of the operation detection in 1st Example. The schematic diagram which shows the arrangement configuration of the operation ring 101 and the friction wheel 105 in a 1st Example. Detailed view showing the contact state between the periodic structure portion 101b and the friction wheel 105 in the first embodiment Detailed view showing contact state of periodic structure portion 101b and friction wheel 105 The schematic diagram which shows the arrangement configuration of the operation ring 101 and the friction wheel 105 in 2nd Example. Detailed view showing the contact state of the periodic structure portion 101b and the friction wheel 105 in the second embodiment The schematic diagram which shows the arrangement configuration of the operation ring 101 and the friction wheel 105 in a 3rd Example. Detailed view showing the contact state of the periodic structure portion 101b and the friction wheel 105 in the third embodiment

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[Example 1]
Hereinafter, an imaging apparatus according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 2 is a block diagram of a camera system including a lens barrel according to the present invention. In FIG. 2, reference numeral 1 denotes a camera body of the digital camera, and 2 denotes a lens barrel that is a removable interchangeable lens unit.

  The lens barrel 2 includes a lens group 22 including a plurality of optical lenses, and the lens group includes a focus lens 22a. A lens driving unit 23 that is connected to the focus lens 22a and moves in the optical axis direction is provided. Further, an operation ring 24 that is gripped and rotated by an operator, a rotation amount detection unit 25 that detects a rotation amount when the operation ring 24 is rotated, and an operation detection unit 26 that detects the start of a rotation operation of the operation ring 24 are provided. Is provided. The operation detection means 26 corresponds to the rotation detection mechanism in claim 1.

  Then, the rotation amount detection means 25, the operation detection means 26, the lens system controller 21 that manages the states of the lens barrel 2 and can communicate with the camera body 1 via the electrical contacts 15, and the signals from the operation detection means 26. There is a reset IC 27 that processes and sends a signal to the lens system controller 21.

  The camera body 1 is provided with a camera system control unit 11 capable of switching to a low power consumption mode of the camera and communicating with the lens system control unit 21. Then, the image sensor 14 is arranged at a position where a light beam that has passed through the lens group 22 having the optical axis 20 as an image is formed. After the photoelectric conversion by the image sensor 14, the signal quantized by the A / D converter is an image. It is sent to the processing unit 12. The image processing unit 12 includes a white balance circuit, a gamma correction circuit, an interpolation calculation circuit, and the like, and processes an output signal from the image sensor 14 to generate an image. The image generated by the image processing unit 12 is recorded in the memory unit 13.

  The memory unit 13 includes a processing circuit necessary for recording in addition to the actual recording unit. The camera system control unit 11 manages signals from the image processing unit 12, the memory unit 13, and the lens system control unit 21. Although the camera body has other means and functions related to photographing, it is not a main part of the present invention, so illustration and description thereof are omitted.

  The camera body 1 has three modes: a power-off mode, a photographing enable mode, and a low power consumption mode. The power off mode is a state in which all electrical operations of the camera are turned off, and in the photographing enabled mode, power is supplied to each electronic device by turning on a power button (not shown) from the power off mode. The camera is ready for shooting. The low power consumption mode is a state in which power supply to some electronic devices is suppressed in order to suppress power consumption when the camera operation is not performed for a certain period of time in the image capturing possible mode. On the other hand, the lens barrel 2 also has a low power consumption mode that suppresses power supply to an electronic device unit such as a rotation detection unit described later.

  The configuration of the rotation amount detection means and the operation detection means, which are the main parts of the lens barrel 2, will be described with reference to FIGS. FIG. 3 is a schematic cross-sectional view of the fixed cylinder 100, the operation ring 101, the rotation amount detection means, and the operation detection means. FIG. 4 is a schematic side view showing the configuration of the operation ring 101 and the rotation amount detection means, and FIG. 1 is a schematic perspective view showing the configuration of the operation ring and the operation detection means. The same number is attached | subjected about what has the same function.

  As shown in FIG. 3, an operation ring 101 is provided outside the fixed cylinder 100, and the operation ring 101 is free to rotate around the optical axis 20 with respect to the fixed cylinder 100. The operation ring 101 is provided with a comb tooth portion 101a used for detecting the rotation amount of the operation ring 101 and a periodic structure portion 101b having a periodic uneven structure used for detecting the start of the rotation operation. The periodic structure portion 101 b corresponds to the periodic structure in claim 1. The fixed cylinder 100 is provided with a photo interrupter 102a that detects the amount of rotation of the operation ring 101 by detecting the movement of the comb tooth portion 101a.

  The photo interrupter 102a has a light projecting portion and a light receiving portion, and detects the amount of rotation of the operation ring 101 by passing the comb tooth portion 101a between them. The photo interrupter 102a detects the amount of rotation including the rotation direction in a pair with the photo interrupter 102b (not shown in FIG. 2). The photo interrupter 102 and the comb tooth portion 101a serve as a part of the rotation amount detecting means. In order to detect the start of the rotation operation on the fixed cylinder 100 side, a cylindrical electrode 103 having a conductive portion and a non-conductive portion electrode pattern provided on the side surface of the cylinder is pivotally supported by a bearing 106.

  In addition, electrode brushes 104a, 104b, and 104c that are brought into contact with the conductive portion of the electrode pattern of the cylindrical electrode portion 103 are arranged. A friction wheel 105 that contacts the periodic structure portion 101 b of the operation ring 101 is fitted to the shaft portion of the cylindrical electrode 103. The friction wheel 105 corresponds to a rolling part including an elastic body in claims 1 to 4.

  FIG. 4 shows the configuration of the operation ring 101 and the photo interrupters 102a and 102b, which are rotation amount detection means. Two photointerrupters 102a and 102b are arranged in the vicinity of the fixed cylinder 100. As described above, the comb teeth portion 101a is arranged on the operation ring 101 over the entire circumference. When the operation ring 101 is rotated, the comb tooth portion 101a is rotated accordingly. By the rotation, the slit portion and the light shielding portion of the comb teeth 101a pass between the light emitting portion and the light receiving portion of the photo interrupter. For this reason, the light receiving units of the photo interrupters 102a and 102b may or may not be able to detect the light from the light projecting unit, and this is obtained as a signal.

  By obtaining the signals of these two photon interrupters, the amount of rotation including detection of the rotation direction of the operation ring 101 can be detected. Since the rotation amount detection method including the detection of the rotation direction of the photo interrupter is a known technique, the details are omitted.

  FIG. 1 is a diagram for explaining the mechanism of the operation detection means. As shown in FIG. 1, the operation ring 101 is provided with a periodic structure portion 101 b having a periodic uneven structure over the entire circumference, and the periodic structure portion 101 b is a friction wheel fitted to the shaft portion of the cylindrical electrode 103. 105, and the rotation of the operation ring 101 is transmitted to the cylindrical electrode 103. The cylindrical electrode 103 is supported by a bearing 106. The cylindrical electrode 103 is made of a conductive metal such as stainless steel or copper alloy. Further, the cylindrical portion of the cylindrical electrode 103 is provided with an electrode pattern composed of a conductive portion and a non-conductive portion, which will be described in detail later, and slides in contact with the electrode brushes 104a, 104b, and 104c while receiving rotation.

  The electrode brushes 104a and 104b are in contact with the cylindrical electrode 103 at positions opposite to 180 degrees. Further, 104c is arranged in the vicinity of the electrode brush 104a. The electrode brush 104 is disposed in the fixed cylinder 100, and the other end (not shown) is connected to an electric circuit.

  Next, the electrode pattern will be described with reference to FIG. 5A is a schematic perspective view of the cylindrical electrode 103, and FIG. 5B is a developed schematic view of the electrode pattern of the cylindrical side surface portion 103e of the cylindrical electrode 103. FIGS. 5C, 5D, and 5E. ) Is a schematic side view showing contact between the cylindrical electrode 103 and the electrode brush 104. In FIG. 5, an electrode pattern is arranged on the cylindrical side surface portion 103 e of the cylindrical electrode portion 103, 103 a is a conductive portion, and 103 b indicated by hatching is a non-conductive portion.

  FIG. 5B shows the developed cylindrical side surface portion 103e. As shown in FIG. 5 (b), on the left half side of the cylindrical side surface portion 103e, a conducting portion 103a and a non-conducting portion 103b are arranged in a strip shape at an equal width and an equal pitch. The width 32 of the conducting part 103a is set shorter than the width 33 of the non-conducting part 103b. All the right half sides of the cylindrical side surface portion 103e are conductive portions. The left half side of the cylindrical side surface portion 103e contacts and slides with the electrode brushes 104a and 104b, and the right half side contacts and slides with the electrode brush 104c. FIGS. 5C, 5D, and 5E are schematic views for explaining the electrical connection between the electrode pattern portion of the cylindrical electrode 103 and the electrode brushes 104a and 104b when FIG. 5A is viewed from the arrow direction 31. FIG.

  FIGS. 5C, 5D, and 5E show the difference in the contact state between the cylindrical side surface portion 103e and the electrode brushes 104a and 104b, respectively, as the cylindrical electrode 103 rotates. 5C, the conductive portion 103a is in contact with the electrode brush 104a, FIG. 5D is in contact with the electrode brush 104b, and FIG. 5E is the electrode brush 104a, Both 104b are in a non-contact state. As shown in FIG. 5B, the electrode pattern is arranged such that the width 32 of the conducting part 103a is shorter than the width 33 of the non-conducting part 103b. , (D), or (e).

  On the other hand, the electrode brush 104c is always in contact with the right half of the cylindrical side surface portion 103e in any of the three states described above. That is, the conductive state between the electrode brushes 104 is one of three states: the electrode brushes 104a and 104c are conductive, the electrode brushes 104b and 104c are conductive, and the mutual electrode brushes are nonconductive.

  The ends of the electrode brushes 104a, 104b, and 104c are connected to an electronic circuit, and a signal is detected as two switches by conducting with the electrode brush 104c through the conducting part 103a. Each of the electrode brushes 104a and 104b detects a signal ON when in a conductive state with the electrode brush 104c, and detects a signal OFF when in a non-conductive state with the electrode brush 104c. FIG. 6 shows signals detected from the switches of the electrode brushes 104a and 104b when the operation ring 101 is rotated. A solid line 114a shown in FIG. 6 indicates a switch signal of the electrode brush 104a, and a broken line 114b indicates a switch signal of the electrode brush 104b, and indicates ON / OFF switching depending on a conductive state with the 104c.

  When the electrode brush 104a side switch indicates ON, the electrode brush 104b side switch indicates OFF, and when the electrode brush 104b side switch indicates ON, the electrode brush 104b side switch indicates OFF. With this configuration, both switches are not turned on at the same time. Since it is sufficient to obtain such a signal for detecting the start of the rotation operation, the resolution may be smaller than that of the rotation amount detection means, and the function is satisfied even when the dimensional accuracy of the width of the electrode pattern is low.

  FIG. 7 shows an electric circuit showing the connection between the electrode brushes 104a, 104b, and 104c and the lens system control unit 21. The electric circuit includes a changeover switch having terminals 141a, 141b, and 141c, field effect transistors (FETs) 142a and 142b, resistors 145a and 145b, and terminals 143a, 143b, 144a, 144b, and 146. The terminals 141a, 142b, and 143c of the change-over switch shown here correspond to 104a, 104b, and 104c in FIG. 1, respectively, and the terminal 141c selectively switches between conduction between the terminals 141a and 141b. The terminals 143a and 143b are connected to the lens system control unit, the terminals 144a and 144b are connected to the lens system control unit 21 and the reset IC 27, and the terminal 146 is connected to the power supply Vcc.

  Due to the characteristics of the FET 142a, the lens system control unit 21 connected to the terminal 143a switches the voltage between H (High) and L (Low) so that the conduction state between D (drain) and S (source) of the FET 142a. Can be controlled. When the terminal 143a is set to H, conduction between D and S of the FET 142a becomes possible, and when the terminal 143a is set to L, conduction between D and S of the FET 142a becomes impossible.

  When the voltage of the terminal 143a is L or OFF when the switch terminal 141a side is not conductive with the terminal 141c, no voltage drop occurs in the resistor 145a, and the voltage of the IN terminal 144a of the lens system control unit 21 becomes H. When the voltage of the terminal 143a is H and the switch terminal 141a is in conduction with the terminal 141c, a voltage drop occurs in the resistor 145a, and the voltage of the IN terminal 144a of the lens system control unit 21 becomes L.

  Further, the electrical circuit of the switch terminal portion 141b, the FET 142b, the terminal 144b, and the resistor 145b operates in the same manner as the electrical circuit of the switch terminal portion 141a, the FET 142a, the terminal 144a, and the resistor 145a.

  By adopting this configuration, it is possible to selectively detect ON and OFF of the switch terminals 141a and 141b. Therefore, since the switch that does not consume power when the lens barrel is in the low power consumption mode can be used, the rotation operation of the operation ring can be detected with reduced power consumption.

  Next, processing performed by the reset IC 27 will be described. As described above, the reset IC 27 receives a set of signals from the terminals 144a and 144b in FIG. Then, a signal is output to the input terminal of the lens system control unit 21 based on the received signal. When the signals from the terminals 144a and 144b are (H, H), an L signal is output, and when the signals are (H, L) or (L, H), an H signal is output.

Next, control from when the camera enters the low power consumption mode and the lens barrel enters the low power consumption mode until the operation ring rotates to return the camera from the low power consumption mode will be described.
A control flow of the lens system control unit from when the lens barrel recognizes the low power consumption mode on the camera side until the lens barrel side also enters the low power consumption mode will be described with reference to FIG.

  When the flow is started, it is determined in S1001 whether the camera side is in the low power consumption mode. If it is recognized that the camera is in the low power consumption mode, the process proceeds to step S1002. If it is recognized in step S1001 that the mode is not the low power consumption mode, the process proceeds to step S1004, the terminals 143a and 143b are set to L, and the flow is ended.

  In step S1002, an operation detection operation set operation is performed. The operation detection operation set will be described later.

  In step S1003, power supply to the connected rotation amount detection means is stopped, the lens barrel is set in the low power consumption mode, and the flow is ended. At this time, the output to the terminals 143a and 143b is held.

  Next, the control flow in the set of operation detection means will be described with reference to FIG. When the flow starts, the terminals 143a and 143b are set to H in step S1101. At this time, if the switch terminal 141a or 141b is in a conductive state with the terminal 141c and turned ON, a current flows through S of the FET 142a or 142b, and the terminals 144a and 144b indicate L.

  In step S1012, it is determined whether the terminal 144a is L or not. If it is determined that the terminal 144a is L, it is recognized that the terminal 141a of the switch is ON, the process proceeds to step S1013, the terminal 143a is set to L, and the flow ends. By setting the terminal 143a to L, even when the switch terminal 141a is ON, power is not consumed. Further, as described above, if the switch terminal 141a is ON, the terminal 141b is always OFF, so that power is not consumed unless the operation ring is turned.

  If it is determined in step S1012 that the terminal 144a is not L, the switch 141a is recognized to be OFF, and the process proceeds to step S1104.

  In step S1104, it is determined whether the terminal 144b is L or not. If it is determined that the terminal 144b is L, it is recognized that the switch 141b is ON, the process proceeds to step S1105, the terminal 143b is set to L, and the flow ends. By setting the terminal 143b to L, even when the switch terminal 144b is ON, power is not consumed. Further, since the switch terminal 141a is OFF, power is not consumed unless the operation ring is turned. If it is determined that the terminal 144b is H, it is recognized that both the switch terminals 141a and 141b are OFF, and the flow ends.

  As described above, since the output to the terminals 143a and 143b is held even when the lens barrel is in the low power consumption mode, the outputs (H, H) of the terminals 144a and 144b when the lens barrel is in the low power consumption mode are maintained. ) Is sent to the reset IC 27. Therefore, the signal to the input terminal of the lens system control unit 21 is L.

  When the operating ring is rotated by the operator, the switch is turned on when the conducting portion 103a comes into contact between the electrodes 104a and 104c or between the electrodes 104b and 104c, and the signal of (L, H) or (H, L) is reset. Issued to IC27.

  By receiving the signal, the reset IC 27 pulls up the input terminal of the lens system control unit 21 from L to H, returns the lens barrel from the low power consumption mode, and then returns the camera from the low power consumption mode.

  In this embodiment, the electrode pattern is arranged such that the conductive portion 103a and the non-conductive portion 103b in the contact area with the electrode brushes 104a and 104b are repeated three times each time the cylindrical electrode 103 is rotated once, but this is not restrictive. . As long as the three states shown in FIG. 5C can be repeated, the conductive portion 103a and the non-conductive portion 103b may be provided once or more than three times. Further, regarding the arrangement of the electrode brushes 104a and 104b, as long as the three states shown in FIG. 5C can be repeated, the electrode brushes 104a and 104b need not be arranged at a position 180 degrees opposite to the cylindrical electrode 103. I do not care.

  Next, the details of the mechanical configuration that transmits the rotational force of the operation ring 101 to the rotating electrode 103, which is the main part of the present invention, will be described with reference to FIGS. 3 and 9 to 11. As described above with reference to FIG. 3, the operation ring 101 is provided with the periodic structure portion 101 b which is a periodic uneven structure used for detecting the start of the rotation operation. Further, the cylindrical electrode 103 has a friction wheel 105 fitted to a shaft portion, and the friction wheel 105 is made of an elastic body such as rubber, or partially includes an elastic body. FIG. 9 schematically shows an arrangement configuration of the operation ring 101 and the friction wheel 105 when the lens barrel is viewed from the optical axis direction.

  The cylindrical electrode 103 has a rotational axis parallel to the optical axis and the friction wheel 105 fitted to the shaft portion is pressed against the periodic structure portion 101b by a predetermined charge amount while deforming an elastic portion. The rotational force of the operation ring 101 is transmitted to the cylindrical electrode 103 by the frictional force acting between them. At this time, the periodic structure portion 101b, which is a periodic uneven structure in the operation ring, has an effect of increasing the friction force between the two by contacting only the convex portion with the friction wheel 105. The contact portion between the periodic structures 101b is prevented from slipping, and the transmission of rotational force is prevented from becoming insufficient.

  Although it is possible to reliably transmit the rotational force without slipping by simply using the gear corresponding to the friction wheel 105, an abnormal noise due to the meshing of the gear occurs when the operation ring rotates, and the user feels uncomfortable. Therefore, a friction detection mechanism using friction as in the present invention is required. With the above configuration, it is possible to detect the rotational movement of the operation ring using a mechanical configuration and return the lens barrel from the low power consumption mode with a configuration that does not require standby power.

FIG. 10 is a detailed schematic view showing an enlarged contact portion between the periodic structure portion 101b and the friction wheel 105 in the present embodiment. The friction wheel 105 is disposed in pressure contact with the convex portion of the periodic structure portion 101b of the operation ring 101 by a charge amount h while deforming the elastic body portion. At this time, the center O ₁ of the operation ring 101 of the inner peripheral portion radius R _1, the distance Y ₀ between the center O ₂ of the friction wheel 105 of radius R ₂ is represented by _{Y 0 = R 1 -R 2 +} h . When rotating the operation ring 101 in the rotational direction F ₁ shown, protrusion peak portions which friction wheel 105 and the periodic structure portion 101b are in contact, will Utsurikawa' in the order of S _1, S ₂ shown.

  At this time, as shown in FIG. 11, when the pitch P of the periodic structure is wide and there is only one contact point, the fluctuation of the charging force is large when the convex portion is changed to the convex portion, an impact occurs, and the operation ring 101 There is a problem in that the impact is transmitted to the user's hand that rotates and reduces the quality of the operational feeling.

Therefore, in embodiments of the present invention shown in FIG. 10, the pitch P of the periodic structure, with respect to a radius R _1, the size of each part, such as the radius R ₂ of the friction wheel 105 of the internal gear portion 101b, the appropriate charge amount h Only the friction wheel 105 is press-contacted to the internal gear portion 101b, so that the two are always in contact with each other at two or more convex vertices.

  By constantly contacting multiple locations, fluctuations in the charging force and the impact associated with the transition of the contact point from the convex vertex to the convex vertex are suppressed, and the quality of the operation feeling when rotating the operation ring 101 is improved. Can be made.

The appropriate charge amount h is derived as follows for each part size. As shown in Figure 10, when positioned on the extension of the center O ₂ of the center O ₁ and the friction wheel 105 vertices S ₁ is operating ring 101 of the convex portion with a periodic structure portion 101b, a convex adjacent to the S ₁ the distance between the center O ₂ parts vertex and the friction wheel 105 is farthest. In this case, the vertex S ₂ of the next convex portion so that the positional relationship in contact with the friction wheel 105, by setting the charge amount h in a proper amount is placed in pressure contact with the friction wheel 105 to the internal gear 101b Therefore, it is possible to realize a configuration in which two or more points always contact each other. For this purpose, the length L of the illustrated line segment S ₂ O ₂ corresponding to the distance between the center of the friction wheel 105 and the next convex vertex S ₂ is less than the radius R ₂ of the friction wheel O ₂ by L < R ₂ is required. The length of the line segment S ₂ O ₂ L is represented by formula (1) below using the horizontal component X ₂ and the vertical component Y ₂ of the line segment S ₂ O ₂ in FIG. 10.

L = √ (X ₂ ² + Y ₂ ² ) Equation (1)
Further, when ∠S ₂ O ₁ S ₁ is Δθ, Δθ = P / R ₁ using the pitch P measured along the arc of the periodic structure,
X ₂ = R ₁ sin (P / R ₁ ) ・ ・ ・ Equation (2)
Y ₂ = R ₁ cos (P / R ₁ ) − (R ₁ −R ₂ + h) Equation (3)
And substituting Equation (2) and Equation (3) into Equation (1),
L = √ [R ₁ ² sin ² (P / R1) + {R ₁ cos (P / R ₁ ) −R ₁ + R ₂ −h} ² ] (4)
It becomes.
Here, using the condition of L <R ₂ and the equation (4),
R ₂ > R ₁ sin (P / R ₁ ) (Equation 5)
The charge amount h is h ≧ R ₂ −R ₁ {1-cos (P / R ₁ )} −√ {R ₂ ² −R ₁ ² sin ² (P / R ₁ )} (formula 6)
When the above condition is satisfied, the proper positional relationship is established, and the convex portions S ₁ and S ₂ simultaneously contact the friction wheel 105.

  In the present invention, by using an appropriate charge amount h that simultaneously satisfies the conditions of the above formulas (5) and (6) for the dimensions of each part, a plurality of convex vertices at two or more places are always friction wheels. 105, the impact during operation of the operation ring 101 can be reduced, and the quality of the hand feeling can be improved.

  Note that, as described above, in the method of transmitting the rotational force of the operation ring 101 to the friction wheel 105 by the frictional force of the periodic structure, there is a concern that there is a slight transmission loss of the rotation amount due to both sliding. For this reason, this method is not suitable for moving the focus lens, etc., which requires transmission of a precise amount of rotation. In the present invention, the above configuration is used as an operation start detection means for returning from the low power consumption mode, in which a slight loss of rotation amount is not a problem, so that high quality and standby power are required. There is provided a lens barrel capable of returning from the low power consumption mode with no configuration.

[Example 2]
In the first embodiment, as shown in FIG. 9, the friction wheel 105 is arranged inside the operation ring 101. However, the present invention is not limited to this, and the operation ring 101 has a periodic structure as shown in FIG. The portion 101b may be provided on the outer side of the ring, and the friction wheel 105 may be disposed on the outer side of the operation ring 101. In this case, as shown in FIG. 13, when positioned on the extension of the center O ₂ of the center O ₁ and the friction wheel 105 vertices S ₁ is operating ring 101 of the convex portion with a periodic structure portion 101b, described above FIG. 10, the distance between the apex of the convex portion adjacent to S ₁ and the center O _{2 of the} friction wheel 105 is the longest.

At this time, the length L of the illustrated line segment S ₂ O ₂ corresponding to the distance between the center of the friction wheel 105 and the next convex portion vertex S ₂ is such that the vertical component Y ₂ is as shown in FIG. Unlike the case
Y ₂ = (R ₁ + R ₂ −h) −R ₁ cos (P / R ₁ ) Equation (7)
Therefore, substituting equation (2) and equation (7) into equation (1),
L = √ [R ₁ ² sin ² (P / R1) + {R ₁ + R ₂ −h−R ₁ cos (P / R ₁ )} ² ]... (8)
It becomes.

Here, using the condition of L <R ₂ and the equation (8),
While satisfying the formula (5), the charge amount h is h ≧ R ₂ + R ₁ {1-cos (P / R ₁ )} − √ {R ₂ ² −R ₁ ² sin ² (P / R ₁ ) } ・ ・ ・ ・ ・ Formula (9)
When the above condition is satisfied, the proper positional relationship is established, and the convex portions S ₁ and S ₂ simultaneously contact the friction wheel 105.

  A state in which a plurality of convex vertices at two or more locations always contact the friction wheel 105 by using an appropriate charge amount h that simultaneously satisfies the conditions of the above formulas (8) and (9) for each part dimension. Thus, a lens barrel capable of reducing impact during operation of the operation ring 101 and improving the quality of the hand feeling is provided.

[Example 3]
Further, as shown in a perspective view of the lens barrel 2 seen from the side surface in FIG. 14, the periodic structure portion 101 b may exist at the end of the operation ring 101. At this time, the friction wheel 105 is disposed at the end portion of the operation ring 101 while being pressed against the periodic structure portion 101b while taking a rotation axis in a direction perpendicular to the optical axis. FIG. 15 is an enlarged side view showing a contact portion between the friction wheel 105 and the periodic structure portion 101b.

In this case, as shown in FIG. 15, when the apex S1 of the convex portion having the periodic structure portion 101b is located directly below the center of the friction wheel 105, it is adjacent to S ₁ as in FIGS. the distance between the center O ₂ of the apex of the convex portion friction wheel 105 is farthest. At this time, the length L of the illustrated line segment S ₂ O ₂ corresponding to the distance between the center of the friction wheel 105 and the next convex portion vertex S ₂ is different from the case of FIG. 10 and FIG. The vertical positions in the figure of the convex vertex groups in 101b are equal, and the horizontal component X ₂ and the vertical component Y ₂ are

X ₂ = P Equation (10)
Y ₂ = R ₂ −h Equation (11)
Therefore, substituting Equation (10) and Equation (11) into Equation (1),
^{L = √ {P 2 + (} R 2 -h) 2} ····· formula (12)
It becomes.

Here, using the condition of L <R ₂ and the equation (12),
R ₂ > P ··· Formula (13)
The charge amount h is h ≧ R ₂ −√ (R ₂ ² −P ² ) (14)
When the above condition is satisfied, the proper positional relationship is established, and the convex portions S ₁ and S ₂ simultaneously contact the friction wheel 105.

  A state where two or more convex vertices are always in contact with the friction wheel 105 by using an appropriate charge amount h that simultaneously satisfies the conditions of the above expressions (13) and (14) for each part dimension. Thus, it is possible to reduce the impact when operating the operation ring 101 and improve the quality of the hand feeling.

  As described above, according to the present invention, it is possible to provide a lens barrel having improved quality during the ring rotation operation.

  The present invention is useful for a lens barrel having an operation ring, a camera using the lens barrel, a camera to which the lens barrel is connected, and a camera system including these.

1 camera, 2 lens barrel, 11 camera system controller,
21 lens system control unit, 22 optical lens group, 23 lens drive unit,
24 operation ring, 25 rotation amount detection means, 26 operation detection means, 27 reset IC,
100 fixed cylinder, 101 operation ring, 101b periodic structure part,
102 photo interrupter, 103 cylindrical electrode, 104 electrode brush,
105 Friction wheel, 106 bearing

Claims (5)

A fixed cylinder;
A ring member having a periodic structure portion that is rotatable around the fixed cylinder and has a periodic uneven structure on at least one of an inner peripheral surface, an outer peripheral surface, and an end surface;
A lens barrel provided with a rotation detection mechanism installed in the fixed cylinder,
The rotation detection mechanism has a rolling part including an elastic body,
The rolling part including the elastic body is configured to be in pressure contact with the periodic structure part with a predetermined charge amount and to be always in contact with the periodic structure part at a plurality of two or more points. A lens barrel. The ring member has the periodic structure portion on the inner peripheral surface, the radius is R ₁ , the pitch of the periodic structure is P, the radius of the rolling portion including the elastic body is R ₂ , and the predetermined charge amount is h
R ₂ > R ₁ sin (P / R ₁ )
The charge amount h is h ≧ R ₂ −R ₁ {1-cos (P / R ₁ )} −√ {R ₂ ² −R ₁ ² sin ² (P / R ₁ )}
The lens barrel according to claim 1, wherein: The ring member has the periodic structure on the outer peripheral surface, the radius is R ₁ , the periodic structure pitch is P, and the radius of the rolling part including the elastic body is R ₂ , the predetermined charge amount h Is
R ₂ > R ₁ sin (P / R ₁ )
And the charge amount h is h ≧ R ₂ + R ₁ {1-cos (P / R ₁ )} −√ {R ₂ ² −R ₁ ² sin ² (P / R ₁ )}
The lens barrel according to claim 1, wherein: Said ring member has said periodic structure on the end face, when the periodic structure pitch and P, and the radius of the rolling portion including the elastic body and R _2, the predetermined charge amount h is
R ₂ > P
And the charge amount h is
h ≧ R ₂ − √ (R ₂ ² -P ² )
The lens barrel according to claim 1, wherein:   The lens barrel according to any one of claims 1 to 4, wherein the rotation detection result by the rotation detection mechanism is used for an operation start detection unit of the lens barrel.