JPS5832697B2 - Drive device for moving the document table - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for moving a document table in a copying machine or the like by a predetermined stroke.
This relates to a drive device for reciprocating movement.

In an electrophotographic copying apparatus in which a so-called document table moves, the document table is moved by a predetermined distance in response to the rotation of a photoreceptor drum, and an electrostatic latent image corresponding to the document image is formed on the drum. I'm letting you do it.

The above-mentioned predetermined stroke amount is specifically the slit exposure width plus the length of the maximum document that can be copied by the copying apparatus, but as a means for moving the document table by this stroke amount, that is, reciprocating, For example, there is a device that uses a wire to directly drive the document table and a series of pulleys around which the wire is wound, and an electromagnetic clutch is provided on the pulley on the driving side so that the pulley can be rotated in the forward and reverse directions.

In this case, signals for turning on and off the electromagnetic clutch are sent and received by detecting, for example, the rotational position of the photosensitive drum by some means.

That is, the document table is reciprocated by the above-mentioned forward and reverse operations, but in this case, the electromagnetic clutch is turned on and off each time the operation is performed, which often causes failures and is troublesome to set the timing.

The present invention provides a novel document table drive device that does not use means such as an electromagnetic clutch, which can be one of the causes of failure in such devices.

The present invention will be explained below with reference to an illustrated embodiment.

FIG. 1 shows an example of an electrophotographic copying apparatus to which the present invention is applied, and the copying process thereof is performed as follows.

That is, when a document is placed on the document placement glass 2 of the document table 1 and a print button (not shown) is pressed, the photosensitive drum 3 begins to rotate in the direction of arrow a, and correspondingly, the document table 1 rotates in the direction indicated by the arrow. An electrostatic latent image is formed on the photoreceptor drum 3, which is moved forward and charged by the charger 4, by an optical system including a light source lamp 5 and a convergent light transmitter 6.

This image is visualized by a developing brush 7, further transferred onto a copy sheet 9 by a transfer charger 8, and the transferred image on a copy sheet 90 conveyed by a sheet conveying device 11 is fixed by a fixing device 12.

During this time, the residual charge on the photoreceptor drum 3 is removed by the static elimination charger 13, and the drum 3 further rotates.
One copy is obtained after exactly two rotations from the charging start position.

The document table 1 described above moves forward in the direction indicated by the arrow, and after exposure by the optical system is completed, moves back in the opposite direction to return to its initial position.

Here, a specific configuration example for reciprocating the document table 1 based on the above-described process will be described below.

That is, in FIG. 1, a document table 1 is supported so as to be able to reciprocate with respect to the main body of the apparatus.

FIG. 2 shows an example of the support system. The document table 1 is supported by side plates 14.15Vc of the main body of the apparatus, a bearing 16, and a large number of sliding balls 17, and is supported in the vertical and horizontal directions in the figure. It is possible to move freely with an extremely light load while the movement of the robot is restricted.

In FIG. 4, the shaft 18, which is disposed below the focusing light transmitter 6 (see FIG. 1) and has the photoreceptor drum 3 fixed thereto, is connected to the side plates 14 and 15 of the main body of the apparatus (see FIG. 2). is supported via a bearing 19 (the other one is not shown).

A forward gear 22, which is substantially integrated with the coaxial shaft 18 by a half-moon key 21, is attached to the right end of the 18 as viewed from the left in FIG.

As shown in FIG. 5, the gear 22 is integrally or substantially integrally provided with a rotating member 23.
A locked portion, ie, a recessed portion 23a, is formed at one location on the zero circumferential surface, with which a locking member to be described later engages.

In FIG. 4, an operating rotating member 25 is rotatably supported at the right end of the shaft 18 via a bearing 24.
The member 25 and the wire drum 26 are substantially integrated by screws 27.

A relatively long wire 28 is wound in double rows around the circumference of the wire drum 260, and as shown in FIG. 5, it is folded back and tightened with screws 29 in the middle.

Then, one end of the wire 28 is connected to the third
As shown in the figure, the other end is secured to a pin 32 on the left end side of the document table 1, and the other end is secured to a pin 34 on the right end side via a spring 33.

In FIG. 4, the operating rotating member 250 large diameter boss portion 25a
A double-acting gear 36 is loosely engaged with the small-diameter boss portion 25b, and a disk cam 37 as shown in FIG. 5 is connected to the screw 3.
It is fitted by 8.

In FIG.
The boss portion 41a of the bushing body 41 is fitted into the hole 25d, and the bushing body 41 is held immovably by a screw 42.

Another boss portion 41b of the bushing body 41 is fitted into a hole 36a of the reciprocating gear 36, which is larger than the outer diameter of this boss.

A shaft 44 on which a locking member 43 on the forward gear 22 side is integrally fixed is rotatably fitted into the shaft hole of the bushing body 41. As shown in the figure, a clutch lever 45 having a bent piece 45a is fixed to the arm end.

Further, a pin 45b installed at the end of one arm of the clutch lever 45 is fitted into an elongated hole 36b bored above the hole 36a of the double-acting gear 36.

In FIG. 5, a concave portion 37a (see FIG. 6) is formed at one location on the circumferential surface of the disc cam 370, and a stopper 46 is fixed to a portion corresponding to the rotating portion 37a.

An operating piece 45c bent from the thin arm of the clutch lever 45 extends from a close portion of the concave portion 3γa of the disc cam 37 on the opposite side from the stopper 46 (see FIG. 6).

- The actuating lever 47, which has a pin 47a that can be freely engaged and detached from the recess 37a and the actuating piece 45ctC at the end of the arm, and is pivotally connected to the shaft 48, has the habit of turning right around the shaft 48 due to the elastic action of the spring 49. is given.

A release piece 47b bent toward the double-acting gear 36 is formed at the end of one arm of the operating lever 47, and a first renoid 51 is connected to the end of the narrow arm of the lever 47.

Here, in FIG. 5, at the bottom of the forward gear 22,
A drive mechanism for driving the gear 22 is provided, and a gear 54 is rotated from a drive source via a chain 52 and a sprocket 53, and a forward gear is rotated via an intermediate pinion 55, a gear 56 driven thereto, etc. 22 rotates in the same direction as the direction of arrow a of the photosensitive drum 3 which rotates together with the photosensitive drum 3.

In contrast to the forward drive mechanism composed of a series of gears including the forward gear 22 described above, the backward drive mechanism for moving the document table backward is configured as follows.

That is, a lever 58 is provided at the bottom of the backward gear 36 and is pivotally connected to a shaft 51 to which an intermediate pinion 55 on the forward drive mechanism side is fixed.

A gear 59 is fixedly attached to the shaft 57, and the gear 62, which is also attached to the lever 58, is separated from the double-acting gear 36 through an intermediate gear 61 attached to the lever 58, which is engaged with the gear 59. It is designed to rotate in the direction.

A second solenoid 62 is connected to the other arm end of the lever 58, and the lever 58 is given a right-handed rotational behavior around the shaft 57 by the elasticity of a spring 64. Due to this behavior, the hour wheel 62 is held in a position separated from the reciprocating gear 36.

Here, in FIG. 5, the drive motor (
(not shown) begins to rotate, and the gear 56 starts rotating from the chain 52.
Due to the drive system described above, the forward gear 22 rotates in the direction of the arrow along with the rotating member 23 having the recess 23a, and the photosensitive drum 3 also rotates in the same direction.

Moreover, at the same time, the gear 62 on the side of the first drive mechanism for backward movement also rotates in the direction of the arrow in a state separated from the backward movement gear 36.

FIG. 6 shows the above-mentioned state, in which the rotating member 23 having the recess 23a is rotating in the direction of the arrow.

When the first renoid 51 is excited in this state, the operating lever 47 rotates to the left around the shaft 48 against the elasticity of the spring 49, and the pin 47a of the lever 47 is connected to the disc cam 37 as shown in FIG. away from the recess 37a.

Then, the clutch V-par 45 rotates to the right around the shaft 44,
The locking claw 43a of the locking member 43 is connected to the recess 23 of the rotating member 23.
meshes with a.

That is, the locking member 43 has this locking claw 43a in the recess 2.
3a is given a rotational behavior in the direction of engagement, and this behavior is prevented by the pin 47aV: of the permanent actuation lever 47.

By the way, the above-mentioned rotational behavior of the locking member 43 is performed as follows.

That is, in FIG. 5, the side wall 26 of the wire drum 26
A pin 26b is installed in the pin 26a, and another pin 36c is installed in the side surface of the double-acting gear 36 on the wire drum 26 side (see FIG. 4).

A compressible spring 65 is placed between these two pins, and the elasticity of this spring 65 causes the double-acting gear 36 to move into the sixth gear.
In the figure, the wire drum 26 is being rotated clockwise around the shaft 18 and counterclockwise around the shaft 18.

This rotation is prevented in the following manner.

That is, in FIG. 7, the inner peripheral edge of the hole 36a formed in the double-acting gear 36 on the left side in the figure presses against the boss portion 41b of the bushing body 41 due to the elasticity of the spring 65.

In this state, if the actuating piece 45c of the clutch lever 45 is
Push the beveled edge of the lever 45 around the shaft 440
When rotated to the left to the position shown in the figure, pin 4 of the same lever 45
5b presses the left side edge of the elongated hole 36b of the double-acting gear 360, causing the gear 36 to rotate a predetermined amount around the shaft 18, specifically, the large-diameter boss portion 25a of the operating rotating member 25 in FIG. Rotate only the corner counterclockwise.

Then, stretch the spring 65 according to this rotation angle.

Figure 8 shows these relationships.
45 is rotated by an angle α around the shaft 440, that is, when it is rotated from the position shown in FIG. 7 to the position shown in FIG. Rotate by θ and expand the spring 65 accordingly.

Note that in the figure, line AA indicates the center locus of the hole 36a of the double-acting gear 36.

Due to the rotation of the double gear 360, the boss portion 41b of the bushing body 41 is rotated by the double gear 360, as shown in FIG.
It comes into pressure contact with the right inner peripheral edge of the hole 36a of No.6.

In this way, the double-acting gear 36 is charged with a force acting to rotate it clockwise due to the elasticity of the stretched spring 650, and in FIG. As shown in the figure, when the pin 47 is separated from the recess 37a, the pin 47 is moved away from the clutch lever 45.
When the constraint state of a is released, the reciprocating gear 36 rotates clockwise by θ due to the elasticity of the spring 65 described above, and assumes the position shown in FIG. 7.

At the same time, the clutch lever 45 also pivots clockwise around the shaft 44 by an angle α, and assumes the position also shown in FIG.

Here, in FIG. 6, when the print button is pressed and the drive motor starts rotating via a control circuit (not shown),
The forward gear 22 and the rotating member 23 mentioned above rotate in the direction of the arrow, and the first
The solenoid 51 is energized, so that the operating lever 47 rotates to the left around the shaft 48 against the elasticity of the spring 49, and the pin 47a moves into the recess 37 of the disc cam 37.
move away from a.

Then, the clutch lever 45 tries to rotate to the right around the shaft 440, and the locking pawl 43a of the locking member 43, which is substantially integral with the lever 45, comes into pressure contact with the circumferential portion of the rotating member 230, while the clutch lever 43a is already Recess 23a of rotating member 23 in a rotating state
1, the portion 43a engages with the recess 23a as shown in FIG.

At the same time, as shown in FIG. 5, the locking member 43, bushing body 41, and clutch lever 45 all rotate clockwise in a state in which they just revolve around the shaft 18.

As the bushing body 41 revolves, the operating rotating member 2
5 rotates and is substantially integral with the wire drum 26.
And the disc cam 37 rotates clockwise.

That is, the wire drum 26 rotates in the direction of the arrow, and moves the document table 1 forward in the direction of the arrow via the wire 28.

Further, the double-acting gear 36 also has a boss portion 41b of the bushing body 41.
The wire drum 26 rotates in the same direction as the wire drum 26, following the revolution of the wire drum 26.

In FIG. 7, as described above, due to the clockwise rotation of the disk cam 3, the pin 47a of the actuating member 47 is transferred to the circumference of the disk cam 370, and the elasticity of the spring 49 (see FIG. 6) causes the pin 47a of the operating member 47 to move around the circumference. While maintaining this state, the disc cam 37 continues to rotate and reaches the position shown in FIGS. 9 and 10.

That is, in FIG. 9, the bent piece 4 of the clutch lever 45
5a abuts against the side edge 47c of the release piece 47b of the operating lever 47 as the actuating rotating member 25 (see FIG. 5) rotates in the clockwise direction, rotating integrally with the disc cam 37.

FIG. 10 shows just this state. In the same figure, the disk cam 37 further rotates, and as this rotates, the oblique edge 46a of the stopper 46 pushes up the pin 47a of the actuating lever 47 that has been transferred to the rotating portion 46a. As shown in FIG. 11, the lever 47 is rotated slightly to the left around the shaft 48 against the elasticity of the spring 49.

At this time, the release piece 47b of the operating member 47 is
Rotate the clutch lever 45 to the left around the shaft 44 (see FIG. 12) to the position shown in FIGS. Similarly, the locking member 43 is rotated to the left in the same direction, and now at 11.
The locking pawl 43a of the locking member 43 that was engaged with the recess 23a of the rotating member 23 separates from the recess 23a.

In this state, the wire drum 26 (see Fig. 5)
The rotation of the document table 1 stops, and at the same time, as shown in FIG. and stops at the position it moved to.

In the above-mentioned state, the slit exposure for the original image of the original is completed, and this signal is captured and the second
The solenoid 62 is energized, and as a result, the V-bar 58 rotates to the left against the elasticity of the spring 64 around the shaft 5T, and is maintained in a position separated from the double-acting gear 36 at Konjaku 1. The gear 62 of the member 58, which has been rotated in the direction of the arrow, meshes with the reciprocating gear 36 as shown in FIG.

Then, the gear 36 begins to rotate in the opposite direction to the previous rotation direction, that is, in the counterclockwise direction.

Then, as shown in FIG. 12, the hole 36a of the double-acting gear 36
The boss portion 4 of the bushing body 41 that abuts the inner peripheral edge on the right side of
1b is pushed by the gear 36 and revolves counterclockwise around the shaft 18, and at the same time, as shown in FIG. Rotate.

That is, the wire drum 26 rotates in the opposite direction to the direction indicated by the arrow in the figure, and by reversing the wire drum 26, the document table 1 is started from the position indicated by the chain line via the wire 28 and the pulley 31 as shown in FIG. Return to position.

Here, due to the above-mentioned counterclockwise rotation of the disk cam 37 in FIG. 11, the pin 47a of the operating lever 47 is transferred from the oblique edge 46a of the stopper 46 to the circumferential surface of the disk cam 37 as shown in FIG. go.

At this time, the bent piece 45a of the clutch lever 45 moves away from the release piece 47b of the operating lever 47, and the first
In FIG. 2, the clutch lever 45 attempts to rotate clockwise around the shaft 440 due to the stored elasticity of the spring 65.

That is, although the locking pawl 43a of the locking member 43 tries to fall into the recess 23a of the rotating member 23, the rotating member 23 remains independent even when the engagement operation between the locking member 43 and the locking member 43 is released. Therefore, as shown in FIG. 13, the locking pawl 43a moves away from the recess 23a and transfers to the space between the rotating members 230 while being in pressure contact with the rotating member 230, resulting in the above-described falling movement of the locking pawl 43a. can't happen.

Then, the disk cam 37 rotates from the position shown in FIG. 13 to the position shown in FIG. It falls to 37a.

By the way, in FIG. 6, a toothed part 36d is provided at one location on the circumference of the double-acting gear 36, and the toothed part 36d is formed by cutting out a predetermined number of teeth. reaches the position shown in Figure 14, and gear 3
6 rotates and reaches the position corresponding to the driving side gear 62, the mesh is disengaged and the driven side double-acting gear 36
The rotation of should be stopped.

In this state, as described above, the pin 47a of the operating lever 47 is inserted into the recess 37a of the disc cam 37 as shown in FIG.
The document table 1, which had been moving back from the imaginary line to the starting position in FIG. 3, stopped at the starting position.
Further, the stopper 46 revolves from the position shown in FIG. 14 to the position shown in FIG. 6, and its left side edge 46b comes into contact with the pin 47a of the operating lever 47, thereby regulating the document table 1 at the starting position.

During this time, that is, when the toothless portion 36c of the double-acting gear 36 comes to the gear 62 in FIG. 14, or the transmission relationship is severed, the electric circuit is energized for the first time as shown in FIG. The second solenoid 620, which was supposed to maintain its excitation effect, is deenergized, and the lever 58 is rotated clockwise around the shaft 570 by the elasticity of the spring 64 and returned to its original position as shown in FIG. Insertion tooth portion 3 of moving gear 36
Leave 5d.

In FIG. 6, the pin 47a of the operating lever 47 is depressed into the recess 37a of the disc cam 37, so the locking pawl 43a of the locking member 43 is in the recess 23a of the rotating member 23 in the rotating state. , first solenoid 51 (fifth
(see figure) will not fall unless it is energized.

As described above, when the double-acting gear 36 reverses, the locking pawl 43a of the locking member 43 may not engage with the recess 23a of the rotating member 23. I can say that.

Note that the copying of the -cycle is completed when the photosensitive drum 3 has rotated twice, and at the same time, the rotation of the forward gear 22 and the rotating member 23, which are in a normally rotating state in FIG. 5, is stopped.

As described above, in the embodiment of the present invention, as shown in FIG. 5, the document table is moved forward by rotating the forward gear 22 in the forward direction, and the document table is moved backward by rotating the backward gear 36 in the reverse direction. Since the locking member 43 automatically performs the so-called clutch action of disconnecting and connecting the drive transmission relationship with the wire drum 26 interposed between them, safety is ensured. Since the series of drive and clutch actions are performed mechanically, the operation is reliable and there are fewer failures than when using means such as an electromagnetic clutch.

In the present invention, a copying apparatus in which the photosensitive drum rotates twice to obtain one copy has been described; however, the present invention is not limited to this; The present invention can also be applied to.

In addition, in this embodiment, a one-wire type was described as shown in FIG. All you have to do is move it around.

As described above, according to the present invention, a locking member having a clutch action is interposed between the forward and backward drive mechanisms for reciprocating the document table and the operating rotating member connecting the document table, and this movement is automatically performed. Therefore, the reciprocating movement of the document table is performed mechanically and reliably, and there are fewer failures than those using an electromagnetic clutch, and the operation is highly safe.

[Brief explanation of drawings]

FIG. 1 is a front view showing an example of an electrophotographic copying apparatus to which the present invention is applied, FIG. 2 is a longitudinal cross-sectional view of the document table in the device, and FIG. 3 is a diagram for explaining the reciprocating movement of the document table. FIG. 4 is a vertical cross-sectional view of the main drive section of the document table moving drive device according to an embodiment of the present invention, seen from the left in FIG. 1, and FIG. FIG. 6 is an exploded perspective view of the device, FIG. 6 is a front view showing the main drive unit in the flat position in FIG. 4, and FIG. FIG. 8 is a diagram for explaining the relationship between the clutch lever rotation and action and the related backward movement gear, and FIG. 9 shows the document table in the forward movement state. FIG. 10 is an operational view taken from FIG. 9 showing the state of the document table just before the end of its forward movement, and FIG. Figure 12 shows the clutch lever in the same position as Figure 11.
A front view of the main part showing the relationship between the double-movement gear hole and the boss part of the bushing body, Figure 13 is an operational view from Figure 11 when the document table has started to move backward, and Figure 14 is the document table FIG. 14 is an operational diagram from FIG. 13 showing a state immediately before completing the backward movement. 1...--Original table, 22, 54, 55, 56...
... Forward drive mechanism, 23 ... Rotating member, 2
3a... Open locking part, 25... Operating rotation member,
36,59°61.62... Double-acting drive mechanism,
43...Curved locking member.

Claims (1)

[Claims] 1. A forward drive mechanism that moves the document table forward, a backward drive mechanism that moves the document table backward, a rotating member that is interlocked with the forward drive mechanism and has a locked portion, and the backward drive mechanism. It has an operating rotational member connected to the document table, and a movement habit that is attached to the operating rotational member and tries to engage the above-mentioned locked part, and when engaged with the locked part, the above-mentioned A locking member that integrally rotates the rotating member and the operating rotating member to move the document table forward; means for releasing the blocking action and engaging the locking member with the locked portion; and releasing the engagement action when the forward movement of the document table is completed, and the document being moved backward by the backward movement drive mechanism. 1. A driving device for moving a document table, comprising means for holding the release operation until the table returns to the starting position.