JPS61184247A - Rotation transmission mechanism - Google Patents

Abstract

PURPOSE:To enable selective transmission of a power to 2 systems of wheel trains, by shifting rotation of a worm between a forward and a reverse direction. CONSTITUTION:With a driving motor 1 forward rotated as shown by an arrow mark (a), a worm 5 is located in a first position and geared with a first worm gear 6 to drive the gear 6 in the direction of an arrow mark (c). Meanwhile, the motor 1 shifted to a direction reverse to the arrow mark (a), the worm 5 is rotated in a direction shown by an arrow mark (b), the first worm gear 6 is forced to rotate in the direction reverse to the arrow mark (c), but, since the gear 6 is checked through the force of a leaf spring 8, the gear is prevented from rotation, the worm 5 is moved leftward from the first worm gear 6, and is moved to a second position. In which case, the worm 5 is geared with only a second worm gear 9 to drive the gear 9 in the direction of an arrow mark (d). The first and second worm gears 5 and 9 are respectively coupled to 2 systems of wheel trains.

Description

Detailed Description of the Invention Technical Field The present invention relates to a rotation transmission mechanism, more specifically, a rotation transmission mechanism that selectively transmits the driving force of one drive source to two transmission trains according to the forward and reverse rotation of the drive source. Regarding the mechanism.

Conventionally, when selectively driving two train systems, it is necessary to selectively rotate the drive motor provided for each train, or
One drive motor is rotated in one direction, and a clutch mechanism is provided between this motor and the wheel train to perform switching.

The former requires two drive motors, and a circuit for driving and controlling each motor must be provided for each motor, while the latter requires a clutch mechanism, making the configuration complex and requiring the use of an electromagnetic clutch. There were problems in terms of configuration and cost, such as the need for a control circuit.

Purpose An object of the present invention is to provide a rotation transmission mechanism that has a simple configuration and is inexpensive.

Structure: The present invention rotates a worm in forward and reverse directions using a driving means, and when the worm rotates forward, the worm engages with a first worm gear at a first position to rotate the first worm gear.
When the worm rotates in the reverse direction, the worm moves to the second position by the thrust force applied to the first worm gear, meshes with the second worm gear, and rotates the second worm gear. The first worm gear and the second worm gear are connected in different rows.

Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

13= In FIGS. 1 and 2, reference numeral 1 indicates a drive motor, such as a DC motor, as a drive means whose rotation direction can be switched between forward and reverse directions. Output shaft 2 of drive motor 1
A worm shaft 3 is connected and fixed to the worm shaft 3. The worm shaft 3 is supported by bearings 4a and 4b of the substrate 4 so as to be rotatable and slidable in the axial direction. A worm 5 is fixed to the worm shaft 3. The drive motor 1 is supported by support means (not shown) so as to be movable in the axial direction.

Therefore, the worm 5 is movable between the bearing parts 4a and 4b. Hereinafter, as shown in FIG. 1, the position where the worm 5 abuts the end surface of the boss portion 5a against the bearing portion 4a will be referred to as the first position, and as shown in FIG. The position where the end surface of the boss portion 5b abuts against the bearing portion 4b is referred to as a second position.

A first worm gear 6 that meshes with the worm 5 when the worm 5 is in the first position is rotatably provided on the base plate 4 by a support shaft 7. As will be described later, the first worm gear 6 is rotated in the direction indicated by the forward rotation of the worm, but rotation in the opposite direction to this rotation direction is prevented by a leaf spring 8 as a non-return means. . Further, a second worm gear 9 is rotatably provided on the base plate 4 by a support shaft 10, which meshes with the worm 5 which rotates in the opposite direction when the worm 5 is in the second position. As will be described later, the second worm gear 9 is rotated by the worm in the direction indicated by the arrow, but rotation in the opposite direction to this rotation direction is prevented by a leaf spring 11 as a check means. The non-return means is not limited to a leaf spring, and any suitable means such as a one-way clutch or a ratchet mechanism may be used.

The relative positions of the first worm gear 6 and the second worm gear 9 in the axial direction of the worm shaft are set as follows. The worm 5 meshes only with the first worm gear 6 in the first position shown in FIG. 1, and only with the second worm gear 9 in the second position shown in FIG. When moving, it passes through an intermediate position where it meshes with both worm gears 6.9 at the same time. That is, both worm gears 6.9 are positioned so that they can mesh with the worm 5 independently and simultaneously.

Now, in FIG. 1, if the drive motor 1 is rotating forward in the direction shown by arrow a, the worm 5 is in the first position and meshes with the first worm gear 6, and rotates the gear 6 in the direction of arrow C. Drive rotation.

When the rotational direction of the drive motor 1 is switched to the direction opposite to the arrow a, the worm 5 rotates in the direction already indicated by the arrow, and attempts to rotate the first worm gear 6 in the direction opposite to the arrow C. However, since the gear 6 is checked by the leaf spring 8, it does not rotate.

Therefore, the worm 5 rotating in the direction indicated by the arrow is moved to the first worm gear 6 by the thrust force against the first worm gear 6 which does not rotate
Move to the left in the diagram.

The worm 5 moving leftward passes through an intermediate position where it meshes with the first worm gear 6 and the second worm gear 9, and then reaches the second position shown in FIG. This second position is
The worm is held by the boss portion 5b abutting against the bearing portion 4b. The worm 5 located at the second position meshes only with the second worm gear 9 and rotationally drives this gear in the direction of arrow d.

As shown in FIG. 2, when the rotation direction of the worm 5, which is rotating in the direction of the arrow A, is switched to the direction of the arrow a, the second worm gear 9 attempts to rotate in the direction of the arrow d, but is reversed by the leaf spring 11. It cannot be rotated because it is stopped. For this purpose, the worm 5 is moved toward the first position shown in FIG. 1 by the thrust force against the second worm gear 9, which is stationary.

The first worm gear 5 and the second worm gear 9 are each connected to two systems of transmission trains (not shown), and when each gear is rotated by the worm 5, it rotationally drives each transmission train.

When the worm 5 is engaged with one of the worm gears to rotate it, there is friction between the boss parts 5a, 5b of the worm 5 and the bearing parts 4a, 5a, which are in contact with each other, depending on the load of the transport train. is occurring. Turn-7= Depending on the magnitude of the load on the wheel train being rotated and driven, it is desirable to take appropriate friction reduction means between the two.

In the illustrated embodiment, since the worm 5 and the worm shaft 3 are integrated, the motor and the worm both move in the same direction according to the rotational direction of the drive motor 1, but the drive motor 1 is fixed. It may be arranged as follows. in this case,
The worm 5 is attached to the worm shaft 3 using appropriate means such as a key so as to be relatively movable in the axial direction and integrally in the rotating direction. When such a configuration is adopted, the worm 5 is rotated depending on the rotation direction of the drive motor 1.
only is moved between the first and second positions.

Next, an application example of the rotation transmission mechanism of the present invention will be explained.

FIG. 3 shows a two-stage cassette type paper feeding device in a recording device such as a copying machine or a facsimile machine. This paper feeding device includes a negative paper feeding mechanism 12, a lower paper feeding mechanism 13,
It consists of a pair of registration rollers 14 that receive recording sheets selectively sent out from both mechanisms and convey them to a recording section (not shown). Upper paper feed mechanism 12 and lower paper feed mechanism 13
The configuration includes a paper feed path 1 that communicates with a pair of registration rollers 14.
5. ! 6 have the same length, and their arrangement positions are separated into upper and lower sections. Therefore, the configuration of the upper paper feed mechanism 12 will be explained, and the structure of the lower paper feed mechanism 13 will be described in "Two-copy paper feed". An alphabetic letter is added to the reference numeral indicating the structure of the mechanism 12, and the explanation thereof will be omitted.

The upper paper feeding mechanism 12 includes a feed roller 17 that rotates in the direction of the arrow to feed the recording paper in the paper feeding direction, and a feed roller 17 that is stopped or rotates in the opposite direction to the paper feeding direction and feeds paper other than the topmost paper. a friction roller 18 that suppresses the advance of the recording paper S, a pickup roller 19 that sends out the stacked recording paper S toward both rollers 17 and 01, a cassette 20 that stores the recording paper S, and a movable roller of this cassette. bottom plate 20a of
a bottom plate push-up lever 21 for pushing up the recording paper stacked on the plate and lifting the uppermost recording paper to a predetermined position relative to the pickup roller 19; and a bottom plate drive for swinging this lever. It consists of a shaft 22.

The cassette 20 is detachably attached to a cassette holder (not shown). When the bottom plate pusher 21 is swung by a rotation transmission mechanism to be described later, the recording paper S is raised to a predetermined position relative to the pickup roller 19. Figure 3 shows both the upper and lower bottom plate presses.
Nileper 22.22L also shows a 1-elevated form.

The sole drive shaft 22 and the sole drive shaft 22L are selectively driven by a rotation transmission mechanism shown in FIG. In addition, in FIG. 4, the drive motor 1 explained in FIG. 1, the worm 5, and the first . The second worm gear 6.9 is given the same reference numeral. An operating lever 23 is fixed to the bottoming drive shaft 22. The free end 23a of this lever 23 is positioned on the rotation locus of the engagement pin 25, which is equivalent to the end surface of the drive shaft 24.

The drive shaft 24 is rotatably supported by an axle 26,
A toothed portion 24a is formed on its outer periphery. Tooth portion 24a
The small diameter tooth portion 27a of the idle gear 27 is engaged with the small diameter tooth portion 27a of the idle gear 27. The large-diameter tooth portion 27b of the idle gear 27 meshes with the small-diameter tooth portion 28 that is integral with the -10-th worm gear 6. Hereinafter, the reduction gear train from the first worm gear 6 to the drive shaft 24 will be referred to as the -th gear train 29.

A second wheel train 30 consisting of a similar reduction gear train is also provided between the bottomed drive shaft 22L and the second worm gear 9.

Regarding the configuration of this gear train, the reference numerals assigned to the first wheel train 29 will be given an alphabetic letter, and a detailed explanation will be omitted.

The drive shaft 24.24L is movable in the axial direction of the support shaft 26.26L, and when the cassette 20.20L is not attached, the engagement pin 25.25L is connected to the free end 23a, 23aL of the actuation lever. It is retracted to a position where it does not engage, and when the cassette is installed, it is moved to a position where both can be engaged. Also, if the cassette is installed and the top recording paper is not at the specified height,
A recording paper level sensor (not shown) is activated to turn on the drive motor 1.

In FIG. 4, when the cassette 20 is loaded and its recording paper is not at a predetermined level, the drive motor 1 rotates in the direction of arrow a to position the worm 5 at the first position. The rotation of the drive motor 1 is decelerated and transmitted to the drive wheels 24 via the worm 5 and the first wheel train 29, causing the drive shaft 24 to rotate in the direction indicated by the arrow.

When the drive wheel 24 rotates, one of the engagement pins 25 engages the operating lever 23, causing it to swing in the direction of arrow e. Swinging of the operating lever 23 causes the bottom plate push-up lever 21 to swing in the direction of arrow e via the bottoming drive shaft 22. The bottom removal push-up lever 21 engages with the bottom plate 20a of the cassette 20,
This is raised, and the recording paper stacked at the bottom is raised to a predetermined position relative to the pickup roller 19, as shown in FIG. When a recording paper level sensor (not shown) detects that the uppermost recording paper has been raised to a predetermined height, the power to the drive motor 1 is cut off and the motor is stopped.

When the cassette 20L is installed, the recording paper stored in it is not yet placed at a predetermined height position, so a recording paper level sensor (not shown) detects this and moves the drive motor 1 with the arrow Give a signal to rotate in the direction of the arrow opposite to a. When the drive motor 1 rotates in the direction indicated by the arrow, the worm 5 moves to the second position explained in FIG. make it move. As shown in FIG. 3, when a recording paper level sensor (not shown) detects that the uppermost recording paper has been raised to a predetermined position relative to the pickup roller 19L, the drive motor 1 is activated by the detection signal. be stopped.

As described above, the two transducers 29 and 30 are selectively rotationally driven by the forward and reverse rotation of one drive motor 1.

Recording paper is selectively fed out from the cassette 20.20L. Then, when the height of the stored recording paper decreases, the drive motor 1 is rotated in either the forward or reverse direction based on a signal from the recording paper level sensor that detects this.

Depending on the rotational direction of this drive motor, the worm 5 is placed in a first position (see FIG. 1) or a second position (see FIG. 2), and the worm 5 is placed in the first worm gear 6 or the second worm gear 9.
1. The second wheel train 29, 30 is selectively driven to rotate.

Effects of the Invention As described above, the present invention provides a rotation transmission mechanism with an extremely simple configuration in which the rotation of the drive means is selectively transmitted to two transmission lines simply by switching the rotation of the worm between forward and reverse directions. can be obtained.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 show an embodiment of the present invention, and the $1l
iifil"9"-4"'@ * M' a W't
-M*' 1r front view, FIG. 2 is a front view showing a mode in which the worm is located in the second position, FIG. 3 is a front view showing an example of a two-stage cassette type paper feeder to which the present invention is applied, Fourth
The figure is a front view showing the bottom push-up mechanism of the paper feeder to which the rotation transmission mechanism of the present invention is applied. DESCRIPTION OF SYMBOLS 1... Drive means, 5... Worm, 6... First worm gear, 9... Second worm gear.

Claims (1)

[Claims] A worm rotatable in forward and reverse directions and movable between a first position and a second position in its axial direction; and selectively driving the worm to rotate in forward and reverse directions. a driving means; a first worm gear that meshes with and rotates the worm when the worm is rotated in the forward direction and is in the first position; A second worm gear that rotates by meshing with a worm located at a second position through an intermediate position where the first worm gear meshes with the first worm gear, a first worm gear that meshes with and rotates with the worm that rotates in the forward direction, and a worm gear that rotates with the worm that rotates in the opposite direction. and a check means for preventing the second worm gears from rotating in opposite directions, and when the worm rotates in the forward direction, the worm is in the first position and rotates the first worm gear, and the worm rotates in the opposite direction. When the worm rotates in the reverse direction, the worm moves to the second position by thrust force against the first worm gear, meshes with the second worm gear, and rotates the second worm gear.