JPH04319929A - Film winding mechanism with clutch - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates primarily to a clutch mechanism for a film winding mechanism of a camera.

0002

2. Description of the Related Art Conventionally, in a film winding mechanism of a camera, when attempting to manually pull out a film wound onto a spool, the following occurs. As shown in FIG. 4, the first mechanism is that the gear head 32 and spool 31 are directly connected to the gear head output shaft 34 and the spool bearing 33, so the spool 31 must rotate, but the gear head 32 Because it did not rotate, it was not possible to pull out the film. In other mechanisms, although not shown, a method has been adopted in which the gear head is placed outside the spool and a slip mechanism or clutch mechanism is constructed between the gear head and the spool.

However, conventional film winding mechanisms either do not have a slip mechanism or a clutch mechanism, or the slip mechanism or clutch mechanism that does have a problem that they have many parts, are large in size, and are expensive. It had a point.

0004

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a space-saving and inexpensive film winding mechanism with a clutch that allows the film wound around a spool to be manually pulled out.

[0005]

[Means for Solving the Problems] The film winding mechanism with a clutch of the present invention has a winding motor 2 in a spool 4, a gear head 8 directly connected to the winding motor 2, and a gear head 8 connected to an output shaft portion 9 of the gear head. The clutch member 11 is housed, and the spool 4 and the clutch member 11 engage with each other in a trapezoidal tooth shape, and the clutch member 11 is connected to the spool 4 and the base plate 1 having a leaf spring function.
It is characterized by a structure sandwiched between 6 and 6. Furthermore, the shape of the spool 4 is characterized in that the clutch tooth profile portion 7 is provided on the inner peripheral portion of the transmission spur gear 6.

[0006]

Embodiments Examples of the present invention will be described below with reference to the drawings. FIG. 1 shows an overall diagram of an embodiment of the present invention.
A winding motor 2, a gear head section 8, and a clutch member 11 are housed inside a spool 4 at a film winding portion of a camera frame 1. The hoisting motor 2 is fixed to a motor fixing base 3 with screws, and the motor fixing base 3 is fixed to the frame 1 with screws. The spool 4 has a spool claw 5 on its outer periphery. The spool claw 5 hooks the sprocket hole in the film, and the spool 4 rotates to wind up the film. Further, when the film is manually pulled out, the spool 4 is rotated by the film pulling force being transmitted to the spool claw 5. The bearing when the spool 4 rotates is supported by the motor fixing base 3, and the other bearings are supported by the output shaft part 9 of the gear head part 8 housed in the spool 4, and the spacer on the base plate 16. 15 is a bearing. Furthermore, when rewinding the film wound around the spool 4 by reversing the winding motor 2, the spur gear part 6 on the spool 4 rotates in the reverse direction, thereby transmitting the transmission of the intermediate gear a18, intermediate gear b19, etc. The gear is turned to rotate the batrone core that stores the film, and the film is wound up. The intermediate gear A18 transmits the rotational force to the transmission gears such as the intermediate gear b19, and transmits the rotation to the fork at the center rotation of the cartridge. Although not shown, there is a swinging lever whose swing rotation is centered around the rotation of the spur gear 6, and on the swinging lever there is a swinging gear that meshes with the spur gear portion 6. Spool 4 rotates forward (
When the spool 4 moves in the film winding direction), the swing lever rotates in the direction of escape to the intermediate gear a18, and since the swing gear and the intermediate gear a18 do not mesh with each other, the intermediate gear a18 does not rotate. However, when the spool 4 rotates in the reverse direction (rewinding the film and winding it onto a cartridge), the swing lever rotates in a direction that meshes with the intermediate gear a18, and the swing gear and the intermediate gear a18 mesh with each other. Therefore, the reverse rotation of the spool 4 rotates the intermediate gear a18, transmits the rotation to the intermediate gears, rotates the fork, and rewinds the film. The base plate 16 has a thin plate shape with spring properties, and is usually made of iron-based metal. It is also the base of the spacer 15 that supports the output shaft portion 9, and is fixed to the frame 1 with a set screw 17. The intermediate gear a18 and the intermediate gear b19 are gears that transmit rotational force from the spool to the fork. boss 2
0 is the central axis of intermediate gear a18 and intermediate gear b19,
This is a guide shaft that fixes the base plate 16 to the frame 1 with a set screw 17.

FIG. 2 is a detailed view of FIG. 1 of the present invention. The shaft 10 of the output shaft portion constitutes a radial bearing with the spool 4. The gear head section 8 decelerates the rotation of the hoisting motor 1, converts it into low speed rotation and high torque, and transmits it to the output shaft section 9. or,
Since high torque is transmitted to the output shaft portion 9, the gear head portion 8 is required to have rigidity that can withstand the high torque. Since the hoisting motor 2 and the gear head section 8 are contained within the cylindrical shape of the spool 4, they have a cylindrical shape. Therefore, the output shaft portion 9
coincides with the center of the cylindrical shape of the spool 4. An example of such a gear head 8 will be explained in detail. The motor shaft 21 is the output shaft of the hoisting motor 2, is located on the central axis of the cylindrical outer shape of the motor, and has a D-cut anti-rotation shape. The sun gear 22 is a gear that transmits the rotation of the motor shaft 21. The lower case 23 is fixed to the hoisting motor 2 and holds a fixed circular gear 26. The planetary gear 24 is held by a holder body 25, and the sun gear 22 and the fixed internal gear 2
6. It meshes with the movable internal gear 27. The holder body 25 holds the planetary gear 24 and connects the lower case 23 and the movable internal gear shaft 2.
8 is a bearing supported at both ends, and rotates on the central axis of the motor shaft 21. Therefore, by rotating the sun gear 22 integrally with the motor shaft 21, the planetary gears 24 are moved to the holder body 25.
It rotates on its own axis while being supported by the motor shaft 21, and also revolves around the central axis of the motor shaft 21. In addition, the fixed internal gear 26 and the movable internal gear 2
Since there is a difference in the number of teeth 7, the movable internal gear 27 decelerates the rotation of the sun gear 22 according to the principle of a differential gear, and rotates with high deceleration torque. The movable internal gear 27 is composed of a tooth profile portion of internal teeth, a movable internal gear shaft 28, a shaft 10 of an output shaft portion, and an output shaft portion 9. In this way, since the gear head section 8 uses a planetary gear mechanism, it can obtain a large reduction ratio and large torque with a small size, and has the additional advantage that it does not rotate even if a rotational force is applied from the output shaft section 9 side. have.

FIG. 3 is an operational diagram of the present invention. The clutch tooth profile part 7 of the spool is located inside the spur gear part 6 and outside the bearing part of the spool 5, and the tooth profile is arranged radially from the central axis of the spool 5, and the cross-sectional shape from the circumferential direction is a trapezoidal tooth profile. . The clutch tooth profile portion 13 of the clutch member has tooth profiles arranged radially from the central axis of the clutch member 11, and its cross-sectional shape in the circumferential direction is a trapezoidal tooth profile. Since the clutch tooth profile 7 of the spool and the clutch tooth profile 13 of the clutch member have the same shape in the same straight line from the central axis, they mesh perfectly.

Before explaining the operation, the clutch member 11 will be explained in detail with reference to FIGS. 6, 7, and 8. A clutch member bearing portion 12 is located at the center and has a cross-like spline shape. The output shaft portion 9 also has a cross-shaped spline shape with respect to the central axis. Therefore, the clutch member bearing portion 12 and the output shaft portion 9 are fitted into each other in a bearing-shaft relationship. Therefore, the rotational force of the output shaft portion 9 can be transmitted to the clutch member 11. Furthermore, the output shaft portion 9 and the clutch member 11 can slide in the direction of the central axis. The clutch tooth profile portion 7 of the spool and the clutch tooth profile portion 13 of the clutch member have the shape shown in the perspective view in FIG. As shown in the clutch tooth shape 14 shown in FIG. 6, the clutch teeth are created in a radial shape toward the zero point on the central axis.

The operation of the present invention will be explained with reference to FIG. First, the film winding function will be described. The winding motor 2 rotates in the winding direction, the spool 4 rotates, and the spool claw 5 hooks into the sprocket hole of the film to wind the film. The rotation of the hoisting motor 2 rotates the output shaft portion 9, and the rotation of the output shaft portion 9 rotates the clutch member 11. The clutch member 11 is sandwiched between the spool 4 and the base plate 16, and the clutch tooth profile 13 of the clutch member and the clutch tooth profile 7 of the spool are in mesh with each other, so the rotation of the clutch member 11 is transmitted to the spool 4 and winds the film. increase. When winding of the film is finished, the spool 4 cannot rotate, but when the output shaft portion 9 attempts to rotate, action and reaction forces act on the clutch tooth profile 7 of the spool and the clutch tooth profile 13 of the clutch member, causing the clutch teeth to rotate. Since the shape is trapezoidal, a force in the rotational direction and a thrust force in the axial direction of the spool 4 are generated. This thrust force is proportional to the rotational torque, and the clutch member 11 causes the base plate 16 to deflect due to the thrust force, and the amount of deflection of the base plate 16 is proportional to the rotation torque. The winding torque generated at the end of film winding shifts the clutch tooth profile 7 of the spool and the clutch tooth profile 13 of the clutch member, causing the clutch member 11 to bend the base plate 16. However, the spring strength of the base plate 16 is set so that the clutch tooth profile 7 of the spool and the clutch tooth profile 13 of the clutch member do not come off under this winding torque.

Next, when the film wound around the spool is manually pulled out, the torque applied to the spool 4 is larger than the torque at the end of film winding. Therefore, as the force for drawing out the film increases, the amount of engagement between the clutch tooth profile 7 of the spool and the clutch tooth profile 13 of the clutch member gradually decreases, and eventually they come off. The force with which the clutch teeth are disengaged is regarded as a torque applied to the spool 4, and is called clutch torque. In this manner, when the force for drawing out the film exceeds the clutch torque, the teeth of the clutch portion disengage and the spool 4 rotates, allowing the film to be drawn out. In the clutch-equipped film winding mechanism of the present invention, the shape of the clutch teeth, the materials of the spool 4 and the clutch member 11, and the base plate are selected so that the clutch torque is in the range of 1.2 to 3 times the winding torque. This is achieved by setting 16 spring constants.

FIG. 5 is a conceptual diagram of FIG. 3 of the present invention. Therefore, a conceptual explanation of the clutch mechanism will be given with reference to FIG. The shaft 10 of the output shaft part is part of the movable internal gear 27 and part of the output shaft part 9, and is fitted into the bearing part of the spool 4. When a force is applied to pull out the film, the clutch tooth profile 7 of the spool and the clutch tooth profile 13 of the clutch member tend to rotate relative to the central axis of the spool 4, and rotational torque is applied. Since the clutch tooth profile is trapezoidal, the clutch member 11 functions to deflect the trapezoid 16. As the force for drawing out the film increases, the amount of deflection of the base plate 16 increases in proportion to the force. The amount of engagement between the clutch tooth profile 7 of the spool and the clutch tooth profile 13 of the clutch member is also proportional to the film drawing force. When the film drawing force increases, the clutch teeth disengage, the spool 4 rotates, and the film is drawn out.

[0013]

[Effects of the Invention] As described above, according to the present invention, since it is sufficiently small compared to known similar clutch mechanisms and film winding mechanisms, the space saving effect is large, the reliability is high, and the number of parts is reduced. A film winding mechanism with a clutch that is small in size and low in cost is provided.

[Brief explanation of drawings]

FIG. 1 is an overall view showing one embodiment of the present invention.

FIG. 2 is a detailed view of FIG. 1 of the invention.

FIG. 3 is an operational diagram of FIG. 2 of the present invention.

FIG. 4 is a sectional view showing a conventional example.

FIG. 5 is a conceptual diagram of FIG. 3 of the present invention.

FIG. 6 is a sectional view of the clutch member of the present invention.

FIG. 7 is a plan view of the clutch member of the present invention.

FIG. 8 is a perspective view of the clutch tooth profile of the present invention.

[Explanation of symbols]

1 Frame 2 Hoisting motor 3 Motor fixing base 4 Spool 5 Spool claw 6 Spur gear part 7 Clutch tooth profile 8 Gear head part 9 Output shaft part 10 Output shaft shaft 11 Clutch member 12 Clutch member bearing part 13 Clutch tooth profile 14 Clutch tooth profile shape 15 Spacer 16 Base plate 17 Set screw 18 Intermediate gear 1 19 Intermediate gear 2 20 Boss 21 Motor shaft 22 Sun gear 23 Lower case 24 Planetary gear 25 Holder body 26 Fixed internal teeth 27 Movable internal teeth 28 Movable internal gear shaft 31 Spool 32 Gear head part 33 Spool bearing part 34 Output shaft part

Claims (3)

[Claims] 1. A hoisting motor, a gear head directly connected to the hoisting motor, and a clutch member coupled to an output shaft of the gear head are housed in a spool, and the spool and the clutch member engage with each other through clutch teeth. Further, the film winding mechanism with a clutch is characterized in that the clutch member is sandwiched between the spool and a base plate having a leaf spring function. 2. The film winding mechanism with a clutch according to claim 1, wherein the clutch tooth profile is provided on the inner circumference of the transmission spur gear in the shape of the spool. [Claim 3] The clutch torque when manually pulling out the film wound on the spool is 1.2 times the torque on the spool of the film end lock generated when the winding motor finishes winding the film. 2. The film winding mechanism with a clutch according to claim 1, wherein the clutch is set to three times.