JPS63235207A - Motor roller - Google Patents

Abstract

PURPOSE:To prevent the damage of a seal by leading in one end of a hollow tube together with a power feeding wire to a roller housing through a shaft member, and drawing out the other end to the area of no seal outside the housing, in a motor roller for a roller conveyer. CONSTITUTION:When the inner air pressure in a roller housing 11 rises, the pressure in the housing is released through a hollow tube 40. Therefore, a sealing device 24 is prevented from a damage by the inner pressure of the housing 11. As a result, the damage of the electric circuit system resulting from the invasion of oil or water into a motor roller 10 can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to improvements in motorized rollers used in roller conveyors for conveying articles.

<Prior Art> In order to convey articles, roller conveyors in which a plurality of rollers are arranged side by side at appropriate intervals in the conveying direction are often used in various fields. The holder incorporates a motorized roller that actively rotates itself.

These motor rollers have a common structure that includes a roller housing that is rotatably mounted around a shaft member, and an electric current that is housed within this roller housing and drives the roller housing to rotate around the shaft member. a motor; a seal device disposed around the shaft member at both ends of the roller housing for sealing the inside of the roller housing; and a seal device extending from at least one end of the roller housing through the shaft member. Furthermore, in order to effectively utilize the driving force of the motor, a planetary gear mechanism or the like is usually incorporated inside the roller housing to achieve a desired reduction ratio.

In this way, this type of motor roller for roller conveyors houses relatively precise electrical and mechanical systems inside, so no matter what environment it is used in, there will be no moisture or oil inside the housing. In order to prevent the intrusion into the rollers and protect these mechanical systems, it has been pointed out in the past that sufficient consideration should be given to the sealing performance with the shaft member, especially at the end of the roller.

(Problems to be Solved by the Invention) For the above-mentioned reasons, conventional motor rollers do not have a so-called normal oil seal structure or cap seal structure between the shaft members at both ends that support the roller and the roller ends. In addition, these sealing devices themselves, including their materials, are already almost complete technology, so they are certainly extremely resistant to external pressure, and therefore, under static conditions, they are resistant to external dust and dirt. It was successful in effectively preventing moisture from entering.

However, in the past, when this type of motor roller was used in a working environment where oil and moisture were directly exposed to it, the seal, which was supposed to be tight, broke and the oil and moisture entered the inside of the roller housing. However, accidents such as malfunctions and fires often occur due to damage to the motor's electrical circuit system. Moreover, this even occurred shortly after the installation of a new roller conveyor.

The present invention has been made to investigate the causes of such accidents and to provide sufficient measures for this type of motor roller to prevent them.

Means for Solving the Problems> In order to achieve the above object, the present inventor first investigated and explored the cause of the accident in the above conventional example.

As a result, we found that the conventional sealing device described above is unidirectional, and as mentioned above, the condition that pressure is applied only from the outside to the inside of the roller housing is always met. If so, although it certainly has a sufficient sealing function, it is surprisingly weak against pressure in the opposite direction, that is, pressure from inside the roller housing, and even a slight increase in this can easily cause deformation, such as turning over. Met.

On the other hand, such an increase in the internal pressure of the roller housing
It is easily caused by the heat generation of a motor running in a closed roller housing.

For this reason, although it was not possible to understand this with a static model that looked only in one direction, such as applying pressure from the outside to the inside of the roller housing, it is possible to When the motor generates heat, the air pressure inside the roller housing increases, and this deforms the sealing device with a force that lifts it up from the inside, creating a gap between the roller housing and the shaft that supports it. A mechanism occurs in which moisture and oil from the outside environment intrude through the rollers, causing failure of the motor rollers in a short period of time as described above, and in severe cases, smoke and ignition.

Based on this knowledge, the present invention provides a motor roller having the following configuration to solve these problems.

a roller housing rotatably mounted around the shaft member; an electric motor housed within the roller housing for rotationally driving the roller housing around the shaft member; A sealing device disposed around the shaft member to seal the inside of the roller housing, and a power supply line extending from at least one end of the roller housing through the shaft member to the motor. A motor roller for a roller conveyor; one end opening of the hollow tube is pulled into the roller housing together with the power supply line through the shaft member, and the other end opening of the hollow tube is drawn into the outside of the roller housing together with the power supply line. A motor roller characterized by: being able to extend the area to a space where sealing is not required;

(Operations and Effects) According to the present invention, the internal environment of the roller housing is in communication with a spatial region (separated from the working space) that does not require sealing via the hollow tube.

Therefore, even if the internal temperature of the roller housing rises when the motor operates, the resulting increase in internal air pressure is released to the outside through the hollow tube. The risk of damaging the sealing function by applying unexpected pressure from the seal can be sufficiently prevented.

Furthermore, as mentioned above, if the cause of the accident in the conventional example is found, the usual measures that can be taken are to make the sealing device two-stage, one to deal with the force from the outside of the roller housing to the inside, and one to deal with the force from the outside of the roller housing to the inside. One method is to deal with the force from the inside to the outside, but this method naturally increases costs and increases the size of the roller housing. According to the configuration of the invention, such problems do not occur.

<Embodiment> The attached drawing shows a front view of an example of a motor roller IO to which the present invention is applied, with main parts cut away.

The motor roller IO has a cylindrical hollow roller housing 11.
The surface thereof becomes a so-called roller surface 12, on which the article is placed and flows.

This roller housing 11 has a central shaft member 1 at both ends.
3.15, but the shaft member 13 shown on the left in the figure simply physically connects one end of the roller housing 11 to a suitable support structure (not shown), such as a conveyor frame structure. The shaft member 15 shown on the right has this physical support function as well as the function of supplying power to the internal motor 16. It also has the role of passing the line 26, and therefore has a hollow cylindrical shape. In the illustrated case, the motor 16 is assumed to be for three-phase AC drive, so there are also three power supply lines 26.

For convenience, the explanation will begin with the operation of the motor 16; however, when power is supplied to the motor 16 and driving force is applied to the sun gear 18 connected to the output shaft of the motor, this sun gear 18
is substantially in a fixed relationship with the non-rotatable shaft member 13 supporting the roller housing 11, so the housing structure or stator of the motor 16 tends to rotate around the sun gear 18.

Since this motor housing or stator is substantially dynamically integrated with the roller housing 11, a predetermined reduction ratio is achieved by a planetary gear mechanism 21 including a sun gear 18, a planetary gear 19, and an internal gear 20. As a result, the roller housing 11 rotates around the shaft members 13 and 15.

In order to make this rotation smooth, suitable bearings 17, .

is provided.

On the other hand, as mentioned above, in this type of motor roller, the side of the motor stator that receives power through the power supply line 26 rotates, so it is necessary to prevent the power supply line 26 from twisting. The end of the power supply line 26 passing through the member 15 and entering the roller housing 11 is connected to the motor 16 via a sliding contact device 30.

However, this sliding contact device 30 is a known existing device that is often used for this type of purpose, and has fixed contact surfaces 27 and 28.
, 29, and a brush 3:l that rubs on this contact surface.
, , , each brush 33 is connected to the corresponding contact surface 27
, 28 , 29 , a spring 3 that presses in the axial direction
4, , and an insulating sliding plate 31 for supporting the contact surface.
It consists of a brush support plate 35.

In the illustrated case, among the contact surfaces carried by the sliding plate 31, the innermost contact surface 27 is located at the center of rotation of the roller housing, and therefore serves as a disk-shaped or dot-shaped conductor region with a certain area. The contact surface 28 is formed in a ring shape surrounding the contact surface 27, and the outermost contact surface 29 is formed as a ring-shaped conductor whose diameter is further increased concentrically. .

The material of the sliding plate 31 that bears the fixed contact surfaces 27 to 29 is a suitable ceramic or plastic, and the overall shape in this embodiment is a disk having each of the contact surfaces 27 to 29 on its surface. The base of the shaped portion extends to penetrate into the interior of the shaft member 15, and a contact end is formed at this extended end to which a caulking contact or the like of the power supply line 26 inserted from the outside is connected.

Under such a configuration, in order to ensure sealing performance at the ends of each of the shaft members 13 and 15 supporting the roller housing 11, oil seals 22 and cap seals 23 are installed using conventional techniques. A sealing device 24 is provided.

These sealing devices 24 may be provided with the same configuration and shape as conventional ones, and in that case, as already explained, the pressure applied from the outside to the inside part of the roller housing 11 will be sufficient. Although it can perform a seal function,
If a relatively large pressure is generated inside the roller housing 11, the roller housing 11 may be turned up from the inside and deformed.

Therefore, in the present invention, the shaft member 1
A hollow tube 40 is passed through the roller housing 5, and its one end opening 41 is pulled into the roller housing 11, and the other end opening 42 of the hollow tube 40 is pulled out together with the power supply line 26 to a space outside the roller housing where sealing is not required. There is.

For example, the terminal of the power supply line 26 is connected to a power distribution board or the like that is installed in a place away from the work space and away from water or oil, so this is a spatial area that does not require a seal. As an example, the other end opening 42 of the hollow tube 40 may be pulled out together with the hollow tube 40 and placed by simply hanging inside the switchboard. Of course, it is preferable to cover and seal the power supply line 26 with a covering means 44 (imaginary line) such as an ordinary heat shrink tube 44 up to this spatial region where sealing is not required.

In this regard, a bushing 25 or the like is also inserted inside the shaft member 15 as a further auxiliary sealing means.

In any case, with the addition of the hollow tube 40 according to the invention, the increase in the internal pressure of the roller housing 11 is released through this hollow tube 40, thus making the sealing device 24 as small as the conventional device. Even if it is kept to a relatively simple and inexpensive device in terms of scale or unidirectionality, its functionality will not be compromised. However, this means that even such a simple sealing device can effectively perform its sealing function according to the present invention, and does not mean that a strict sealing device should not be provided. Even when a higher-grade, high-performance sealing device is installed, if there is a hollow tube 40 that releases internal pressure in accordance with the idea of the present invention, even higher performance can be expected.

Also, the area where the air pressure can be the highest is the motor 1.
6, when looking at the illustrated cross section, there is a sliding contact device 30 between the area where the motor 16 is located and the area where the opening 41 at one end of the hollow tube 40 faces. There is a plate 31 and a brush support plate 35, and their outer peripheral surfaces are in close contact with the inner peripheral surface member of the roller housing, and it appears that there is no gap, but in reality, in this type of motor roller, there is no gap between them. Since a gap is created that allows free air circulation, it is not possible for the internal pressure in the vicinity of the motor area 16 to escape to the opposite side of the sliding contact device 30 from which the hollow tube opening 41 faces. There is no need to worry about that.

However, of course, if desired, channels may be formed to actively allow air flow, as exemplified by the grooves 45 formed along the surface of the sliding plate 31 in the illustrated embodiment; However, the brush support plate 35 may be provided with through holes instead of grooves, and the brush support plate 35 may also be provided with through holes or grooves.
The opening 41 at one end of the hollow tube 40 may be brought to the nearest point.

As is clear from the above description, the present invention is not limited in application to the motor roller IO having the illustrated structure, but can be applied to almost all motor rollers of this type.

[Brief explanation of the drawing]

The accompanying drawing is a fragmented front view showing essential parts of an example of a motor roller to which the present invention is applied. In the figure, IO is the motor roller as a whole, 11 is a roller housing, 12 is a roller surface, 13.15 is a shaft member, 1
6 is a motor, 17 is a bearing, 21 is a planetary gear mechanism,
22 is an oil seal, 23 is a cap seal, 24 is the sealing device as a whole, 26 is a power supply line, 30 is a sliding contact device, 31 is a sliding plate that carries the fixed contact surfaces 27, 28, and 29, and 35 is a brush 33 ．． , , , 40 is a hollow tube, 41 is an opening at one end of the hollow tube, 42 is an opening at the other end, and 45 is a groove formed for air circulation.

Claims (1)

[Scope of Claims] A roller housing rotatably mounted around a shaft member, an electric motor housed within the roller housing for rotationally driving the roller housing around the shaft member, and an electric motor for rotating the roller housing around the shaft member; sealing devices disposed around the shaft member at both ends to seal the inside of the roller housing; and a power supply to the motor drawn out through the shaft member from at least one end of the roller housing. A motor roller for a roller conveyor, the motor roller having a track, wherein one end opening of the hollow tube is drawn into the roller housing together with the power supply line through the shaft member, and the other end opening of the hollow tube is connected to the power supply line. A motor roller characterized in that the track is extended to a space outside the roller housing where sealing is unnecessary.