JPS6095748A - Cam driving device - Google Patents

Abstract

PURPOSE:To reduce number of components and to simplify a trigger mechanism by applying triggering once for one reciprocating operation of an operation button through the relation of engagement between a prescribed projection and latched projection so as to ensure operation very surely. CONSTITUTION:The latched projections 24a-24d are formed on the surface of a cam gear 21, a cam 25 is provided on the rear face, and a drive gear 20 is arranged in opposition to the gear 21. In depressing the operation button 27, the engagement between the projection 28a of an operating rod 28 and the latched projection 24b is released, the gear 21 is turned counterclockwise by a spring 26 and the gear 21 and the drive gear 20 are meshed with each other. Thus, the torque of the gear 20 is delivered to the gear 21, the operating force is extracted to an external mechanism via the cam 25 and trigger is applied once. The relation of engagement is restored to the initial state by the restoration of the operation button 27. Thus, the operation is conducted surely and stably, the number of parts is made less and the trigger mechanism is simplified.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a cam drive device that uses the rotational force of a motor to switch operation modes in devices such as magnetic recording and reproducing devices, and has a simplified trigger mechanism. It is.

Conventional configurations and their problems In recent years, magnetic recording and reproducing devices that use the rotational force of a motor to switch between operating modes without using direct force have become popular9. There is also a remarkable movement towards reducing costs.

Among these, a gear cam with missing teeth is used to utilize the rotational force of the motor, and the small force of the drive trigger of the sheep gear cam is used as the operating force.

It has been proposed that the trigger be activated by a single reciprocating motion (wanpuku/yu) of the operating button, making it operate as if it were activated by an electrical switch.

A conventional cam drive device will be described below with reference to FIGS. 1, 2, and 3.

FIG. 1 is a plan view of a conventional cam drive device.

1 is a drive gear that is constantly rotated by a motor.

2 is a cam gear, and the gear portion has one missing tooth portion 2a.

2b - At the center of the front surface there is a retaining part 2C - On the back side there is a cam surface (
(not shown) is provided with the engaging portion 2C.
The eccentric cam shape of the retaining portion 2C urges the cam 472 to rotate counterclockwise. Reference numeral 4 denotes a control arm supported by a shaft 5 mounted on the mechanical chassis, and is urged by a spring 6 to rotate clockwise.

An operating button 7 is slidable by an operating rod guided by a bottle 13 and biased in one direction by a spring 14. An operating arm 9 is rotatably supported by a shaft 10 mounted on the operating rod 8, and is urged by a spring 11 to rotate counterclockwise. Reference numeral 12 denotes a pin that locks the rotation of the operating arm 9 by the spring 11.

The operation of the cam drive device configured as described above will be explained below.

First, FIG. 1 shows a state in which the operation button 7 is not pushed in. One end 4a of the control arm 4 is engaged with the retaining portion 20 of the cam gear 2, and the cam gear 2 is rotated counterclockwise by the biasing force of the spring 3. It prevents it from rotating in any direction. In this state, the toothless portion 22L of the cam gear 2 is at a position corresponding to the drive gear 1, so the rotational force of the drive gear 1 is not transmitted to the cam gear 2.

Next, when the operation button is pushed in, the operation arm 9 pivotally supported by the operation rod 8 moves in the direction indicated by the arrow. This is υ
The protrusion 4b of the control arm 4 is pushed by the protrusion 9a of the operating arm 9, and the control arm 4 is rotated counterclockwise against the biasing force of the spring 6.

Then, the engagement between the one end 4a of the control arm 4 and the engagement portion 2C of the cam gear 2 is released. Then, the cam gear 2 rotates slightly counterclockwise under the urging force of the spring 3, and the gear portions of the drive gear 1 and the cam gear 2 mesh with each other, and the rotational force of the drive gear 1 is transmitted to the cam gear 2.

As shown in FIG. 3, this rotational force transmission stops when the cam gear 2 rotates half a turn and reaches the final position where the toothless portion 2b faces the drive gear 1, and this state is maintained at one end of the control arm 4.
a and the engaging portion 2c of the cam gear 2 are engaged with each other.

Note that, as the cam gear 2 rotates, any driving force is transmitted from the cam surface formed on the back surface to other mechanisms. Then, when the suppressing force of the operating button 7 is released, the operating arm 9 is rotated clockwise by the urging force of the barb 13 against the urging force of the spring 11, and the operating rod 8 is rotated without moving the control arm 4. will return.

As explained above, the cam gear 2 can be triggered by one reciprocating movement (one button push) of the operation button 7, regardless of the duration of the press.

However, according to the conventional configuration, mechanical parts such as the control arm 4 and the operation arm 9 are required in order to reliably operate the cam gear 2 and switch one operation mode with one reciprocating movement of the operation button 7. The number of parts is large, resulting in high costs, and it is also disadvantageous in terms of space, which hinders miniaturization.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional problems, and provides a cam drive device that reduces the number of parts, has a simple configuration, and can reliably trigger a cam gear with one reciprocating movement of an operation button. The purpose is to provide.

Structure of the Invention The present invention provides an operating rod that is always biased by a spring in the return direction and that can be pushed and slid against the biasing force.

A projection provided on a part of the operating rod; a drive gear driven by a motor; a cam gear having teeth and a tooth-missing part that mesh with the drive gear; and a first part provided on one surface of the cam gear.
and a second retaining protrusion, a cam surface provided on the other surface of the cam gear, and an urging member that applies an urging force in the rotational direction to the cam gear. When the operating rod is not pressed, the protrusion and the first Due to the locking of the locking protrusion, the drive gear locks the rotation of the cam gear due to the biasing force of the biasing member at a position facing the toothless portion of the cam gear, and when the operating rod is pushed in, the driving gear is locked with the first locking position. The projection is disengaged and the cam gear is rotated by the biasing member (as a result, the teeth of the cam gear mesh with the drive gear, the rotational force of the movable gear is transmitted to the cam gear, and the cam surface provided on the cam gear is rotated by the □ external When the operating force is taken out to the cam gear and the meshing between the cam gear and the drive gear ends at the tooth-missing portion - the projection and the second retaining projection engage and the biasing member rotates the cam gear. and when the operating rod is returned to the position where it engages with the second protrusion after snow or when the operating rod is returned to the position where the protrusion and the second
? The engagement force of the engagement protrusion is released, and the cam gear rotates due to the biasing force of the biasing member, and the protrusion and the first protrusion engage with each other to lock the rotation of the cam gear. A cam drive device characterized in that the cam gear extracts power from the teeth between the tooth-missing portions, faces the drive gear within the tooth-missing portions, and is configured so that no operating force is applied to the outside from the cam surface. With a simple configuration, the cam gear trigger is reliably triggered once regardless of the pushing time by one reciprocating push operation of the operating rod, and other mechanical parts are stably driven by the displacement of the cam surface provided on the cam gear. It is something that can be done.

DESCRIPTION OF THE EMBODIMENT FIG. 4 shows a plan view of a cam drive device in an embodiment of the present invention. In Fig. 4, the drive gear 21, which is always rotated by the motor and is decelerated by the motor, is a cam gear.
3&, 23b. 24a, 24b, 24C
924d is a locking protrusion formed integrally on the surface of the cam gear 21, and 26 is a cam integrally formed on the back surface of the cam gear 21.

Further, as shown in FIG. 7, the cam gear 21 has a cam surface (cam groove) 36 on the back surface, and a lever 37 has a pin 36 that is guided by the cam surface 36 as the cam gear 21 rotates.
The operating force for other mechanisms is taken out by this.

Reference numeral 26 denotes a spring whose one end abuts against the cam 25 and always urges the cam gear 21 to rotate counterclockwise.

The 2yH operation button 28 has a protrusion 28L at one end when the operation button 27 is operated, and is always biased by a spring 29. 3o is a guide pin 0 The entire operation of the above configuration will be explained below.

First, when the operation button 27 is not operated, it is in the state shown in FIG.
Since the protrusion 2B& engages with the engagement protrusion 24b of the □ cam gear 21, counterclockwise rotation is prevented. Since the toothless portion 23& of this -1 cam gear 21 faces the drive gear 2o, this rotational force is not transmitted to the cam gear 21.

Next, when the operation button 27 is fully pushed in against the biasing force of the spring 29, the engagement between the projection 28& and the engagement projection 24b is disengaged, and the spring 26
The cam gear 21 is slightly rotated counterclockwise by the urging force. As a result, the tooth portion 22& of the cam gear 21 meshes with the drive gear 2o, and rotational force is transmitted. This state is shown in FIG. The rotational force of the drive gear 20 rotates the cam gear 21, and as shown in FIG. The structure is such that this amount of movement is taken out as a driving force for other mechanical parts.

Further, if the operation button 27 is continued to be pressed from the state shown in FIG. engages with the engagement protrusion 240, and further rotation is prevented. At this time, the toothless portion 23b is in a position facing the drive gear 20, and the rotational force of the drive gear 2o is not transmitted. In this state, as shown in FIG. 7(C), the movement of the lever 37 due to the displacement of the cam surface 36 has ended, and the driving of other mechanical parts has ended.

When the operation button 27 is returned from this state, the engagement between the protrusion 2B& and the engagement protrusion 240 is released, the cam gear 21 rotates counterclockwise due to the urging force of the spring 16, and the retaining protrusion 24& is engaged with the protrusion 2B&. The rotation will be accurate at that point. During this time, since the drive gears 14 face each other within the toothless portion 23, the rotational force of the drive gears 14 is not transmitted to the cam gear 21. Furthermore, the cam gear 21 rotates for a short period of time after the engagement between the projections 28& and the engagement projections 240 is disengaged until the engagement between the projections 28& and the retention projections 241L. There is no length (up to the cam groove), and the lever 37 is configured not to be moved. Therefore, when the operation button 27 is pushed in, the protrusion 28& and the locking protrusion 2 are not driven.
4& is released, the tooth portion 22b meshes with the drive gear 20, the rotational force of the drive gear 20 is transmitted to the cam gear 21, and the lever 37 is moved by the cam surface 36 in the direction opposite to the direction of the arrow B. Return the mechanism to its original position. If the operation button 27 is kept pressed when the teeth of the drive gear 20 and the cam gear 21 have finished engaging, the protrusion 28
a engages with the engagement protrusion 2ad, and then, when the operation button 27 is returned, the engagement between the protrusion 282L and the engagement protrusion 2nd is released, and when the cam gear 21 rotates a little due to the biasing force of the spring 26, the protrusion is removed. 282L engages with the engagement protrusion 24b, the rotation is stopped and it returns to its original position as shown in FIG. This drive gear 2
While o faces the toothless portion 23b of the cam gear 21, the cam surface 36 is not displaced and no driving force is transmitted to other mechanical parts.

Also, press the operation button 27 from the state shown in FIG.
If the operation button 27 is returned immediately after the engagement between the engagement protrusion 2ab and the engagement protrusion 2ab is released, the protrusion 28& will be replaced by the engagement protrusion 24C.
The cam gear 21 rotates until it engages with one engagement protrusion 24& without being engaged with the engagement protrusion 24&.

During this time, as described above, while the driving gear 2o and the tooth portion 22& are engaged and the driving force is transmitted, other mechanical portions are being driven by the lever 37 from the cam surface 35.

Hereafter, each time the operation button 27 is pressed, the above operation is repeated.

As described above, according to this embodiment, the engagement relationship between the projection 2S& and the engagement projections 24a, 24b, 24C, and 24d allows the cam gear to be reliably engaged by one reciprocating push operation of the operation button 27, regardless of the length of time the button is pressed. 21 trigger can be applied once and the operation is stable.

Furthermore, other mechanical parts are driven by the teeth 22a of the cam gear 21,
The cam surface 36 is configured to perform the operation while 22b is engaged.
The operation is stable because of the

In addition, the number of parts is smaller than that of the conventional ρ0, and the configuration is simple, and the space required is small, allowing for miniaturization.

Effects of the Invention The present invention provides an operating rod that is always biased by a spring in the return direction and that can be pushed and slid against the biasing force, a protrusion provided on a part of the operating rod, and a drive gear driven by a motor. a cam gear having a toothed portion and a toothless portion that mesh with the drive gear; - first and second locking protrusions provided on one surface of the cam gear; and a cam surface provided on the other surface of the cam gear; It is a cam drive device consisting of a biasing member that applies a biasing force in the rotational direction to the cam gear, and the cam provided on the cam gear is reliably triggered once by the operation rod's reciprocating pushing action, regardless of the pushing time. Other mechanical parts can be driven by the displacement of the surface.Furthermore, the cam surface is formed so that the driving of other mechanical parts is performed while the teeth of the cam gear are meshing, making the operation very stable. It is something that exists.

In addition, the number of parts is small, the structure is simple, and it is highly effective in practice.

[Brief explanation of the drawing]

1 to 3 are plan views showing a conventional cam drive device, FIGS. 4 to 6 are plan views showing a cam drive device according to an embodiment of the present invention, and FIG. 7 is a plan view showing a cam drive device according to an embodiment of the present invention. FIG. 3 is a plan view showing a cam surface. 20... Drive gear, 21... Cam gear 2
3a. 23 b ・-=Tooth missing part-2aa, 2ab, 240
. 2ad...Engaging protrusion, 26...Spring,
28...Operating rod-2El...Protrusion. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 3
Figure 4 Figure 5 Figure 0? 51 Figure 6

Claims (1)

[Claims] (1) An operating rod that is always biased by a spring in the rear tightening direction and that can be pushed and slid against the biasing force, a projection provided on a part of the operating rod, and a drive gear driven by a motor. and,
A cam gear having a tooth portion and a toothless portion that mesh with the drive gear, and first and second locking protrusions provided on one surface of the cam gear. It consists of a cam surface provided on the other side of the cam gear and a biasing member that applies a biasing force in the rotational direction to the cam gear.
In the non-pressed state of the drive rod, the drive gear locks the rotation of the cam gear due to the biasing force of the biasing member at a position where the drive gear faces the toothless portion of the cam gear due to engagement between the protrusion and the first locking protrusion, and the operation rod In the pressed state, the engagement between the protrusion and the first engagement protrusion is released, and the cam gear is rotated by the biasing member, so that the teeth of the cam gear are engaged with the drive gear, and the rotational force of the drive gear is When the operating force is transmitted to the cam gear and taken out from the cam surface provided on the cam gear, and the engagement between the cam gear and the driving gear ends at the tooth-missing portion due to the rotation of the cam gear, the protrusion and the second retaining protrusion engage. When the rotation of the cam gear is stopped by the biasing member and the operating rod is returned after that or before the engagement of the second protrusion with the protrusion, the engagement between the protrusion and the second engagement protrusion is released. The cam gear is rotated by the urging of the urging member, and the protrusion and the first protrusion are engaged to lock the rotation of the cam gear, so that one reciprocation of the operating rod can move the gap between the teeth of the cam gear. A cam drive device that extracts the power from the teeth and is configured so that it is not opposed to the drive gear within the toothless portion and that there is no operating force from the cam surface to the outside. An operating rod that is biased by a spring in the direction and that can be pushed and slid against the biasing force, and a part of the operating rod (
a drive gear driven by a motor; a cam gear having a tooth portion meshing with the drive gear; and a plurality of tooth-missing portions; and the teeth provided on one surface of the cam gear at the tooth-missing portions. A pair of first and second retaining protrusions that engage with the protrusion so as to face the drive gear at a notch, a cam surface provided on the other surface of the cam gear, and a biasing force in the rotational direction to the cam gear. It consists of a biasing member. When the operating rod is not pressed, the engagement between the protrusion and the first engagement protrusion causes the drive gear to stop rotating due to the biasing force of the biasing member at a position facing the toothless portion of the cam gear;
When the operating rod is pushed in, the engagement between the protrusion and the first engagement protrusion is released, and the cam gear is rotated by the urging member, so that the teeth of the cam gear are engaged with the drive gear, and the rotational force of the drive gear is applied to the cam gear. The operating force is transmitted to the outside from the cam surface provided on the cam gear, and when the cam gear rotates and the engagement between the cam gear and the driving gear ends at the second tooth-missing portion, the projection and the second tooth The second engagement protrusion of the notch engages and locks the rotation of the cam gear by the biasing member, and when the operating rod is returned after that or before the second protrusion and the protrusion are engaged, the protrusion and The second locking protrusion of the second tooth-missing part is released, and the biasing member rotates the cam gear, causing the protrusion to engage with the first protrusion of the second tooth-missing part. After the cam gear is completely locked in rotation, the locking protrusions corresponding to the plurality of missing teeth engage with the protrusions, and one reciprocation of the operating lever moves between the missing teeth of the cam gear. A cam drive device that extracts power from a tooth portion, faces a drive gear within a toothless portion, and is configured so that no operating force is applied to the outside from a cam surface.