JPS592020Y2 - Endless belt misalignment correction device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a deviation correction device for an endless belt that prevents the belt from deviation to either the left or the right with respect to the running direction while the wide endless belt is running.

Conventionally, when an endless belt is conveyed over a predetermined path by a series of rollers, the belt shifts either to the left or to the right with respect to the direction of travel.

To prevent a belt-shaped endless belt with a relatively narrow center from shifting, it is possible to provide a belt roller with flanges that loosely pinch both sides of the endless belt. Even if flanges are provided on both sides of the belt to prevent the belt from shifting, it is not only extremely difficult to prevent the belt from shifting, but also because the side edges of the belt and the flanges rub against each other, causing the belt to slip. This will result in damage to the side edges.

Therefore, it is not preferable to use a member such as a flange that rubs against the side edge of the belt as a means to prevent deviation of the wide endless belt. It is already known that one of the rollers is swingably supported, and when the belt is deflected on the roller, the swingable roller is tilted in a direction in which the end of the belt becomes higher. However, conventionally, this type of device forcibly pushes a movable member with the edge of the belt that is biased to one side, and further transmits the movement of this movable member to the swingable roller via a link mechanism. Due to the tilting of the rollers, the edges of the endless belt are subjected to considerable stress, which also results in damage to the edges of the belt in this device.

This conventional device also has the disadvantage that its construction is very complex.

In order to avoid the use of the relatively complicated link mechanism in the above-mentioned conventional devices, it is possible to electrically detect belt misalignment. The drawback is that not only is the cost high, but the structure is also complicated because it is necessary to add a means to skillfully connect the electrical means and the mechanical means that actually tilts the roller. There is.

An object of the present invention is to provide a misalignment correction device for a wide endless belt that eliminates all of the above-mentioned conventional drawbacks.

When the tension on both sides of a wide endless belt, which is passed between a pair of belt rollers, becomes unbalanced, the belt tends to shift toward the side with greater tension.

Focusing on this behavior, the present invention swings the roller when the belt approaches one side edge, that is, when strong tension is applied to one end of the roller, and increases the tension exerted on the belt by the other end of the roller. The purpose is to correct the misalignment of the belt by smoothing it out.

And, with this invention, no matter which direction the belt moves,
A specific object is to provide a device capable of correcting the deviation of a belt without using any movement of the side edges of the belt or giving the belt a tendency to move in a particular direction.

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

In a copying machine or a sheet conveying device, as shown in FIGS. 1 and 2, a relatively medium-wide endless belt 1 is passed between a swinging roller 2 and a fixed roller 3, and the fixed roller 3 is The shaft is driven by a motor (not shown) that drives the shaft in the direction of greater movement.

The swinging roller 2 is slidably held by self-aligning bearings 5, 5 on a bending shaft 4 whose both ends are bent in a direction away from the fixed roller 3.

Further, the self-aligning bearings 5, 5 are attached to the end plate of the roller 2 by a C-ring 6 around the hole.

One end of the bending shaft 4 is attached to a support plate 9 fixed to a stationary member (not shown), and the other end is attached to a side plate 8 fixed to the stationary member.
Each is supported by

A long hole 7 is bored in the side plate 8, one end of the bending shaft 4 passes through the long hole 7, and the belt 1 is fixed by an adjustment screw 10 and a stopper nut 11 screwed into the bent part 8a of the side plate 8. It is screwed so that it can slide freely in the running direction.

The adjustment screw 10 on the side plate 8 is used to set the inclination of the bending shaft 4 during assembly, and is not necessarily necessary.

Since the embodiment of the present invention is constructed as described above, when the fixed roller 3 is driven by a motor (not shown), the endless belt 1 that is passed between the roller 3 and the swinging roller 2 can be moved. Travel in the direction of high volume.

At that time, both rollers 3 and 2 are kept completely parallel,
In addition, if the thickness of the belt 1 is completely uniform, the belt 1 would run without shifting to the left or right in the running direction, but in reality, the above ideal state is impossible. Therefore, the belt 1 shifts during running.

In order to automatically correct the deviation of the belt 1 while it is running, a swinging roller 2 is used as one of the rollers.

When the belt 1 tension in the width direction of the belt 1 changes due to some cause such as elongation during use or uneven wear on the surface of the roller 2, the belt 1 has a tendency to move toward the side where the belt 1 tension is larger. There is.

For example, in Fig. 2, the distance between the side plate 8 and the side edge of the belt 1 is a, and the gap between the side plate 8 and the end of the roller 2 is C, but when the tension on the right side of the belt 1 increases, the belt 1 Try to move to the right.

At this time, due to the reaction of this deviation, the roller 2 supported by the bending shaft 4 by the self-aligning bearing 5
The tilt angle of the swingable swinging roller 2 with respect to the fixed roller 3 changes as shown in FIG. 3 by moving the top to the left.

That is, the gap between the side plate 8 and the end surface of the roller 2 is narrower than in FIG.

In that case, the distance a between the side plate 8 and the side edge of the belt 1 remains unchanged from that in FIG.

Then, the tension on the right side of the belt 1 is decreased, and the tension on the left side of the belt 1 is increased.

Since the hole of the self-aligning bearing 5 that supports this roller 2 swings on the bending shaft 4, the movement of the roller 2 stops at a position where the belt tension is balanced in the width direction, that is, a position where the deviation of the belt 1 disappears. The belt 1 runs stably.

FIG. 4 shows a comparison of the transitional state and the inclined state of the roller 2 in FIG. 2 and FIG. 3, indicated by α, and the roller 2 in FIG. 2 are respectively indicated by broken lines.

When it is desirable for the belt 1 to run in a fixed position, the regulation foils 12 and 13 are rotatably fixed on both sides of the belt 1 so that their surfaces lightly touch both sides of the belt 1, as shown in FIGS. 5 and 6. do it.

For example, when belt 1 moves to the right while traveling, belt 1
The side edge of the belt 1 is strongly pressed by the circumferential surface of the regulation foil 13, and as a reaction, the swinging roller 2 moves along the bending shaft 4 and stops at an appropriate position where no shifting force is generated. The side edges are not pressed and run stably.

In the present invention, as described above, both ends of the supporting shaft of the swinging roller are symmetrically bent in a direction away from the fixed roller.

The effect of symmetrically bending this support shaft will be explained based on FIG. 7.

FIG. 7 schematically shows how tension is applied to the endless belt with respect to the bending axis.

The tension of the endless belt 1 is applied to the bent portions 4r, 41 of the bending shaft 4 via swing rollers and self-aligning bearings 5,5.

In this case, if the forces applied to the bearings are represented by vectors P, , P2, each bearing has a drag force R1 perpendicular to the axis.
1 and Rlr, and the drag forces R2Q and R perpendicular to the above PI and P2
2r occurs.

At this time, the drag forces R2□ and R21 are forces generated on one roller, the swinging roller, so R2L+
It becomes R2r20 and is in equilibrium.

In other words, the drag forces R2, R2r cancel each other out, meaning that the force applied to the swinging roller does not act to move the endless belt in the axial direction.

Therefore, since there is normally no force that pulls the endless belt in any direction, it is possible to avoid problems such as unnecessary tension between the belt and the swinging roller, and fatigue and deformation of the belt. be understood.

As described above, since the roller of the present invention has its axis symmetrically bent, there is no directionality in the movement of the roller.

In other words, moving from side to side applies the same tension to the belt, and the rollers move smoothly.

In addition, because the roller moves in the opposite direction to the belt shift due to the reaction of the belt shift, the side edge of the belt is prevented from sticking out from one end of the roller and touching the side plate, etc. and causing damage, and the belt can run in a fixed position. .

A similar effect can be obtained by providing a regulating foil in contact with the side edge of the belt.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the main parts of the structure of the present invention, and FIG. 2 is a plan view showing a cross section of the swinging roller of the present invention in its normal position.
Figure 3 is a plan view showing a cross section of the rocking roller moved to the left along the bending axis, and Figure 4 compares the position of the roller and the inclination angle of both rollers in Figures 2 and 3. Fig. 5 is a plan view showing a cutaway cross section of the belt with regulating foils arranged on the side edges of the belt, Fig. 6 is a side view of Fig. 5, and Fig. 7 is a cross-sectional view of the belt on the bending axis. It is a schematic diagram explaining the tension of an endless belt. 1...belt, 2...oscillating roller,
3...Fixed roller, 4...Bending shaft, 5...Self-aligning bearing, 1213...
...Regulation foil.

Claims (1)

[Scope of utility model registration request] A bending shaft whose both ends are bent symmetrically in a direction away from the fixed roller, a pair of self-aligning bearings provided at both ends of this bending shaft so as to be slidable in the axial direction, and these self-aligning bearings enable the above-mentioned An endless belt misalignment correction device comprising a swinging roller rotatably supported on a bending shaft and slidably in the axial direction, and an endless belt stretched between the roller and a fixed roller.