JPS60260757A - Reciprocating device - Google Patents

Abstract

PURPOSE:To obtain a reciprocating device which can be driven at uniform speed and provided at a low price and is small-sized by providing transmitting means adapted to rotate in normal and reverse directions, and transmitting rotation of one of the members to a driven member capable of reciprocating. CONSTITUTION:In case of adopting the above reciprocating device for a driving device for a separating finger in a copying machine, when a lever 13 brought into contact with a rotating cam 12 is turned in direction of an arrow (b) by the drive of a cleaner body, a pinion gear shaft 17 is rotated through a one-way cluch 16 in the lever 13. The rotation is secondly transmitted from a helical gear 19 through a plurality of spur gear trains (not shown) to a pinion gear 25, so that a rack 14 is moved in direction of an arrow E to oprated finger unit not shown through a coupling pin 15. With the movement of the rack 14, switch levers 33, 34 having pins 35, 36 engaged with a groove 14a are pivoted, and at a designated point of time, the engagement form of the above spur gear trains is changed through bases 26, 27 to move the rack 14 in the opposite direction to the arrow E.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a reciprocating device, and more particularly to a reciprocating device that converts unidirectional motion into reciprocating motion.

An example of a device using such a reciprocating device is a drive device for a separating claw provided in an image forming apparatus such as a copying machine, and this will be described below as an example. However, it goes without saying that the present invention is not limited to this example.

Conventionally, this type of device used a cam 1 or the like to slide back and forth in the longitudinal direction of the drum 2, as shown in FIG.
The structure was such that it could not move at a constant speed in the longitudinal direction.

Therefore, when the drum 2 is rotated, the trajectory of the pawl 3 draws a sine curve as shown in Figure 3, and the contact time between the pawl 3 and the surface of the drum 2 at point X is longer than other parts. It becomes very long and has the disadvantage that a flaw 5 is formed on the circumference of the drum at the aforementioned point X when used for a long period of time.

This drawback will be explained in detail with reference to FIG. If the claws draw a sine curve on the circumference of the drum, the movement in the longitudinal direction of the drum will be simple harmonic even if the claws move at a constant speed on the sine curve. Therefore, υ=υocosωt, °・υ=γωcosωt
becomes. (υ0 is the velocity in the tangential direction of uniform circular motion) From this, at the points Al and A2: Cog(1) t =:
Since 0, υ=O, and at point B, since Cogωt=1, υ=γω.

From the above, at point A, the claw is stopped on the drum,
It accelerates from there, passes over the drum at maximum speed at point B, decelerates from there, and comes to a stop again at point A2. This appears as a difference in the contact time of the claws in the longitudinal direction of the drum, resulting in scratches as shown in Figure 2 on the circumference of the drum.

In addition, there are methods to perform reciprocating motion at a constant speed, such as controlling using a stepping motor or using two clutches to perform forward and reverse rotation, but this leads to increased costs and the device itself is The drawback was that it was too large.

The present invention has been made in view of the drawbacks of the above-mentioned conventional examples, and an object of the present invention is to provide a reciprocating device that can be driven at a constant speed.

A reciprocating device of the present invention for achieving the above object includes an input means, a first transmission member that rotates in the normal direction, a second transmission member that rotates in the reverse direction, a driven member that can reciprocate, and the first transmission member. or a switching auxiliary means for positioning the first and second transmission members so that the drive of either one of the first and second transmission members is transmitted to the driven member; a switching means formed on the driven member to control switching timing of the second transmission member, and converting the drive from the input means into reciprocating motion of the driven member. Features.

Hereinafter, the present invention will be explained based on an illustrated embodiment.

FIG. 5 is a diagram showing the present invention attached to the main body of a copying machine. The pawl drive unit 40 is connected to a pawl unit 33 with a pawl 34 by a connecting pin 15, and this pawl unit 33
is guided by the guide rail 32. In addition, 12 is an eccentric cam that rotates using the drive of the cleaner main body, 13 is a lever that is driven by the eccentric cam, 14 is a rack that moves reciprocatingly by the drive, and 15 is a connecting pin with the claw unit.

Next, the configuration will be explained in more detail while explaining the operation.

As shown in FIG. 6, when the lever 13 in contact with the cam 12 which rotates due to the drive of the cleaner main body is driven in the direction of the arrow, the one-way clutch 16 (FIG. 7) inside the lever 13 is activated. The pinion gear shaft 17 (FIG. 1) is locked and rotated in the C direction.

Here, when the cam has escaped, the lever 13 returns to its original position by the spring 18, but at this time, the brake is applied by another one-way clutch 16', and the lever 13 is
3 returns, the pinion gear shaft 17 stops at the position where it was sent by the lever, and is again rotated in only one direction by the lever 13.

Further, this pinion gear shaft 17 is coaxial with the helical gear 19 and rotates together with the spur gear 20 to 21.
, 22, and 24 in the order of □. There is a pinion gear 25 coaxially on the spur gear 24, and this pinion gear 25
is engaged with the rack 14, so the rack moves in the E direction. That is, the pinion gear shaft 17 and the helical gear 19 constitute an input means, and the spur gear 22 constitutes a first transmission member that rotates in the normal direction.

Here, the aforementioned helical gear 19, spur gear 20.23 are on the base 26, spur gears 21.22 are on the base 27, and the bases 26.27 are respectively connected to the shaft 28.
29 can be rotated in the directions of arrows F and G, but link 3
0, so that when the gear 22 (23) on one side is meshing with the gear 24, the gear 23 (22) is not meshed. Furthermore, the link 30 has a click 31 which receives force from a click spring 32 in order to determine its position and instantaneously change gears. In other words, the spur gear 23 transmits the second transmission member that rotates in reverse.
The click 31 and the click spring 32 constitute switching auxiliary means.

Next, this gear switching mechanism will be explained.

As described above, when the rack 14 moves to the left by the drive of the cleaner main body, the groove 14 on the back side of the rack 14
Guide pins 35, 36 of switching levers 33, 34 are guided by a. The switching levers 33, 34 rotate about rotation centers 37, 38, respectively, and are subjected to force by springs 39, 40 such that the guide pins 35, 36 are pressed against one side of the rack groove 14a.

The movement of the guide pins 35 and 36 in the rack groove 14a is the ninth
As shown in the figure, a valve spring 40.41 is incorporated in this groove, and together with the aforementioned spring 39.40, the movement of the guide bin is regulated, and the force of the spring 39.40 causes the guide bin to When falling, the above-mentioned click 31 exceeds the click spring 32.

This movement moves the switching levers 33, 34, and by pushing the link 30 between the bases 26 and 27 in either direction, only one of the gears 22 and 23 will mesh with the gear 24, and this meshing gear will cause The direction of movement of the rack 14 is determined. In other words, the rack groove 14a constitutes a switching means.

Incidentally, switching errors can be prevented by providing a tapered portion 45 in the α portion as shown in FIG.

With the structure described above, the rack 14 is reciprocated, and the claws attached to the rack slide in the longitudinal direction of the drum.

This differs from structures using cams and links, etc. in that the pawls move at a constant speed in the longitudinal direction, and the reverse rotation is instantaneous, so the trajectory of the pawls on the drum is as shown in Figure 10, unlike the conventional method. It has a mechanism that prevents scratches.

The above is an explanation of the embodiment of the reciprocating device according to the present invention, but it goes without saying that the present invention is not limited to this embodiment.

For example, in the above-mentioned embodiment, a trouble means using a click spring 32 as a switching auxiliary means is shown. The position of the base 26, 27 may be switched from side to side using the 26.

In addition, the guide bins 35, 36 and the groove 1 can also be used as switching means.
4a, the rack 14 may directly or indirectly move the bases 26, 27 from side to side.

Furthermore, the rotation of a motor or the like may be directly transmitted to the shaft 28.

Since the reciprocating device according to the present invention has the above-described configuration, it has the effect that the driven member can reciprocate at a constant speed, unlike the conventional structure using a cam and a link, and furthermore, reverse rotation is instantaneous. It has the advantage that it can be done with

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view of an embodiment of the reciprocating device according to the present invention, Fig. 2 is a schematic configuration diagram of a conventional example, Fig. 3 is a diagram showing the locus of a claw on a conventional drum, and Fig. 4. 5 is a diagram illustrating the drawbacks of the conventional example, FIG. 5 is a diagram of the reciprocating device according to the present invention attached to the copying machine body, FIG. 6 is a schematic perspective view of the reciprocating device according to the present invention, and FIG. 7 is a diagram illustrating the drawbacks of the conventional example. A vertical cross-sectional view of a reciprocating device according to the present invention,
FIG. 8 is a sectional view taken along the line B-B in FIG. 1, FIG. 9 is a diagram showing the movement of the guide pin in the rack groove, and FIG. 10 is a diagram showing the locus of the pawl according to the present invention on the drum circumference. 11 are diagrams showing other embodiments of the rack groove. 12-m-Eccentric cam, 13-Momentary lever, 14-Momentary rack, 14a--Rack groove, 16--One-way clutch, 17--Pinion gear shaft, 18-Momentary spring, 19
--- Helical gear, 21.22, 23.24-m- spur gear, 25- momentary pinion gear, 30- momentary link, 31
- momentary click, 32- momentary click spring.

Claims (1)

[Claims] (1) An input means, a first transmission member that rotates in the normal direction, a second transmission member that rotates in the reverse direction, a driven member that can reciprocate, and driving either the first or second transmission member. switching auxiliary means for positioning the first and second transmission members such that the first and second transmission members are transmitted to the driven member; a switching means formed on the driven member to control switching timing of the second transmission member; Features a reciprocating device.