JPH05307284A - Drive transmitting mechanism for image forming device - Google Patents

Abstract

PURPOSE:To obtain the drive transmitting mechanism for an image forming device which is easily assembled without raising cost. CONSTITUTION:In the drive transmitting mechanism for the image forming device in which the rotation of a main driving wheel 8 linked with the motor shaft 4a of a motor 4 is transmitted to a driven wheel through an endless belt, a supporting shaft 9 positioned on the same shaft center as the motor shaft 4a is provided, and the main driving wheel 8 is rotatably attached to the supporting shaft 9 so that its movement in a shaft direction is fixed, then the motor shaft 4a is linked with the main driving wheel 8 so that it can freely move in the shaft direction and fixed in the rotating direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive transmission mechanism for an image forming apparatus such as a copying machine or a printer.

[0002]

2. Description of the Related Art For transmission of driving force of an image forming apparatus, a gear may often cause an increase in load torque and noise, and therefore a timing belt or the like is often used.

FIG. 4 shows a first conventional example, in which a driven pulley 1 and a tensioner 2 are provided near a side plate 3, and a drive pulley 5 is screwed to a motor shaft 4a as shown in FIG. , The motor 4 is connected to the motor shaft 4a via the bracket 6.
Is attached with the side plate 3 side, and the timing belt 7 is wound around the driven pulley 1, the tensioner 2, and the main driving pulley 5.

Next, what is shown in FIG. 6 is a second conventional example (the same parts as those in the above-mentioned conventional example have the same reference numerals), and the motor 4 makes the main body of the motor 4 the side plate 3 side via the bracket 6. The driving pulley 5 is attached to the motor shaft 4a in the same manner as in the conventional example, and the driven pulley 1 and the tensioner 2 are provided at positions apart from the side plate 3 so as to match the driving pulley 5. 2. The timing belt 7 is wound around the driving pulley 5.

[0005]

In the above-mentioned first conventional example, since the motor 4 is located in front of the timing belt 7, it is possible to install it on the assembly line or at the time of maintenance.
The motor 4 is in the way and interferes with the winding of the timing belt 7.

In the second conventional example, since the timing belt 7 is located in front of the motor 4, it is easy to wind the timing belt 7, but since the driven pulley 1 has a long shaft, the tension of the timing belt 7 is increased. In this case, there is a fear that the load torque may increase due to the occurrence of a fall, so that it is often necessary to newly provide a bracket for supporting the shaft near the driven pulley 1.

Since both of these problems are factors of cost increase, they must be solved in today's demand for cost reduction.

Therefore, an object of the present invention is to provide a drive transmission mechanism for an image forming apparatus which is easy to assemble without increasing the cost.

[0009]

According to a first aspect of the present invention, there is provided a drive transmission mechanism of an image forming apparatus for transmitting the rotation of a main driving wheel connected to a motor shaft of a motor to a driven vehicle in an endless belt. A support shaft positioned on the same axis as the main drive wheel is mounted on the support shaft so that the main drive wheel is rotatable and axially fixed, and the motor shaft is movable in the main drive wheel in the axial direction. Fixed in the direction of rotation and connected.

According to the second aspect of the invention, the driving wheel is formed of a thermoplastic resin.

According to the third aspect of the present invention, a guide surface serving as a guide for connecting the main drive wheel and the motor shaft is formed at at least one of the main drive wheel and the motor shaft at the connecting portion between the main drive wheel and the motor shaft.

[0012]

According to the first aspect of the present invention, the main drive wheel is mounted on a support shaft positioned on the same axis as the motor shaft so as to be rotatable and fixed in the axial direction, and the motor is attached to the main drive wheel. Since the shaft is movable in the axial direction and is fixed in the rotational direction so that it can be connected, when assembling on the assembly line, the endless belt can be wound around the main driving wheel and the driven vehicle before mounting the motor. It's easy. Also, during maintenance, even if the motor shaft is pulled out, the motor will not be pulled out because it is mounted so that the movement in the axial direction is fixed, and it is easy to assemble and remove the motor. It will be easier.

According to the second aspect of the present invention, since the driving wheel is made of thermoplastic resin, the driving wheel can be reduced in weight and cost.

According to the third aspect of the present invention, at the connecting portion between the main drive wheel and the motor shaft, a guide surface serving as a guide for connecting them is formed on at least one of the main drive wheel and the motor shaft. As a result, the connection can be done smoothly during assembly, improving work efficiency.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. The same parts as those shown in the conventional example are designated by the same reference numerals. The present embodiment is applied to a cassette bank section in an image forming apparatus. Figure 1
As shown in FIG. 3, a driven pulley 1 serving as a driven wheel and a driving pulley 8 serving as a driving wheel, which are connected to a conveying roller (not shown), are arranged on the side plate 3 with their respective shafts supported, and these driven wheels are driven. A timing belt 7 as an endless belt is wound around the pulley 1 and the driving pulley 8. Further, the motor 4 is attached to the side plate 3 with the tip of the motor shaft 4a inserted into the driving pulley 8 via the bracket 6. In addition, the tension belt 2 is used by the tensioner 2.
Is under tension.

Here, as shown in FIG. 2, the driving pulley 8 has a shaft hole 8a, a D-shaped deformed hole 8b, and a taper 8c serving as a guide surface formed from the side plate 3 side, and has a flange. The supporting shaft 9 is passed through the shaft hole 8a and attached to the side plate 3 by caulking the tip of the supporting shaft 9.

Further, the tip of the motor shaft 4a of the motor 4 is a D-shaped deformed rod like the deformed hole 8b so as to be inserted into the deformed hole 8b of the driving pulley 8. Here, the shapes of the deformed hole 8b and the tip of the motor shaft 4a are not limited to the D-shape, but also by a key (a), an elliptical hole and an elliptic shaft (b) as shown in FIG. ), With a flat hole and a flat shaft (c), with a + -shaped hole and a + -shaped shaft (d), with a star-shaped hole and a star-shaped shaft (e), with a jagged edge A hole and a shaft having a notch (f), a V-shaped hole and a V-shaped shaft (g), and the like are considered.

In such a construction, during assembly on the assembly line, since the driving pulley 8 is previously attached to the side plate 3 together with the driven pulley 1 by the support shaft 9, the timing belt 7 is connected to the driving pulley 8 and the driven pulley. Assembling is easy if the motor 4 is attached after being wound around 1.
Further, when the motor 4 is attached, the tip of the motor shaft 4a is inserted into the driving pulley 8.
Since the entrance of b has a taper 8c, it can be inserted easily and work can be done smoothly. Further, the drive pulley 8 is regulated in the thrust direction by the flange of the support shaft 9, and the rotational force from the motor shaft 4a is transmitted by fitting the D-shaped deformed hole 8b and the tip of the D-shaped motor shaft 4a. Unlike the conventional case, it is not necessary to attach it to the motor shaft 4a with a potato screw or the like, and a metal such as a sintered alloy can be changed to a resin such as a thermoplastic resin, so that the weight and cost can be reduced.

Further, at the time of maintenance, even if the motor 4 is removed and the tip of the motor shaft 4a is pulled out, the driving pulley 8 is not pulled out, and as described above, the motor 4 is easily attached and detached. is there.

In this embodiment, the guide surface for inserting the motor shaft 4a into the main drive pulley 8 is provided as a taper 8c on the main drive pulley 8. However, instead of the main drive pulley 8, the guide surface is provided at the tip of the motor shaft 4a. Alternatively, it may be provided on both the tip of the motor shaft 4a and the drive pulley 8.

[0021]

According to the first aspect of the present invention, the main drive wheel is mounted on the support shaft located on the same axis as the motor shaft so as to be rotatable and fixed in the axial movement, and the main drive wheel is mounted on the main drive vehicle. Since the motor shaft is movable in the axial direction and fixedly connected in the rotation direction, the endless belt may be wound around the driving wheel and the driven wheel before the motor is mounted at the time of assembly on the assembly line. Easy to assemble. Also, during maintenance, even if the motor shaft is pulled out, the motor will not be pulled out because it is mounted so that the movement in the axial direction is fixed, and it is easy to assemble and remove the motor. It will be easier. With such a simple structure, it is possible to improve the assemblability in the assembly line and the serviceability in the market without increasing the cost.

According to the second aspect of the present invention, since the driving wheel is formed of the thermoplastic resin, the driving wheel can be reduced in weight and cost.

According to the third aspect of the present invention, at the connecting portion between the main drive wheel and the motor shaft, a guide surface serving as a guide for connecting them is formed on at least one of the main drive wheel and the motor shaft. Therefore, the connection can be made smooth at the time of assembling, the working efficiency is improved, and the assembling cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

2A and 2B show a driving pulley and a support shaft, FIG. 2A is a perspective view showing an assembling direction, and FIG. 2B is a horizontal sectional view.

FIG. 3 is a front view showing various combinations of deformed bars and deformed holes.

FIG. 4 is a perspective view showing a first conventional example.

FIG. 5 is a perspective view showing screwing of a driving vehicle.

FIG. 6 is a perspective view showing a second conventional example.

[Explanation of symbols]

 1 Driven Vehicle 4 Motor 4a Motor Shaft 7 Endless Belt 8 Drive Vehicle 8c Guide Surface 9 Support Shaft

Claims (3)

[Claims] 1. A drive transmission mechanism of an image forming apparatus for transmitting the rotation of a main driving wheel connected to a motor shaft of a motor to a driven vehicle in an endless belt, wherein a support shaft positioned on the same axis as the motor shaft is provided. And a motor shaft attached to the support shaft so as to be rotatable and movable in the axial direction, and the motor shaft is connected to the main vehicle while being axially movable and fixed in the rotational direction. Drive transmission mechanism of the image forming apparatus. 2. The drive transmission mechanism for an image forming apparatus according to claim 1, wherein the main drive wheel is formed of a thermoplastic resin. 3. A connecting surface between the main drive wheel and the motor shaft is provided with a guide surface serving as a guide at the time of connecting them to at least one of the main drive wheel and the motor shaft. The drive transmission mechanism of the described image forming apparatus.