JPS6235546B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an improvement in a tension adjustment device for applying belt tension to a belt power transmission device within a closed housing.

[Prior art]

Elastic biasing of the belt of a belt transmission device using a tension wheel has been practiced many times in the past, examples of which include Japanese Utility Model Publication No. 1019/1982 and Japanese Patent Publication No. 38822/1983.

However, since these belt transmission devices are applied to equipment that is relatively easy to move, such as agricultural machinery, operations such as belt replacement and belt tension adjustment are easy to perform. For this reason, although the transmission device is housed in a storage case, the tension adjustment device is also structured so that the case lid can be easily opened in the workshop or on site. However, belt power transmission devices that are constantly exposed to high humidity, high temperature, special atmospheres such as dust or volatile substances, and are installed in dangerous locations such as high places, are housed in sealed cast metal housings, and the inside of the housing cannot be opened. It is not intended to be done frequently.

For this reason, the distance between the drive shaft and the driven shaft is made small in advance, and a belt with a short circumference is used, which is designed to reduce the influence of a decrease in tension on belt elongation.

However, in the case of a belt transmission device in which the maintenance cover is not frequently opened, if a conventional tension adjustment device is applied, it is possible to apply a biasing force to the belt from outside the housing. With conventional adjustment devices of this type, it is impossible to judge whether the biasing force is the appropriate size without opening the maintenance cover and checking the belt tension, which leads to work inefficiency. I couldn't get rid of gender.

〔the purpose〕

The present invention has been made to solve these problems, and it is possible to control the tension force on the belt from outside the closed housing, and to control the magnitude of the tension force on the belt at all times during this operation. It is an object of the present invention to provide a tension adjustment device for a belt power transmission device that is configured so that the tension can be visually checked.

[Technical means to solve problems]

In the present invention, a nipple is provided for adjusting the pressure of a spring that applies tension to the wall surface of the housing, and
The nipple is arranged so that the free end of the pressure display shaft can protrude to the outside through a central through hole formed in the nipple.

[Effect]

As a result, the tension force on the belt can be controlled without opening the maintenance cover by operating the nipple that protrudes from the interior of the belt power transmission device to the exterior, and the tension force on the belt can be controlled concentrically with this nipple. Since the penetrating shaft indicates the optimum tension state of the belt, the optimum tension state of the belt can be quickly ensured while visually observing this indicated state. An embodiment of the present invention will be described below with reference to the drawings.

〔Example〕

Here, an example of an upper and lower belt power transmission device will be explained, but it goes without saying that the tension adjustment device of the present invention can also be applied to a one-stage reduction type belt power transmission device.

In addition, in FIG. 1, among the two stages of upper and lower belt transmissions, a variable diameter belt transmission B is installed in the upper stage, that is, the first stage side, and a constant speed ratio belt reducer C is installed in the lower stage, that is, the next stage, respectively, inside the sealed housing 10. Fig. 2 shows a vertical cross-sectional view of a two-stage power transmission device built into the engine. The belt transmitter B may be a constant speed ratio belt reducer similarly to the lower stage.

In the figure, 11 is an input rotating shaft to which a power source such as an induction machine is directly connected, 12 is an intermediate rotating shaft, and 13 is an output rotating shaft to which a load such as a blower fan is attached. Axes 11, 12 and 13
Variable diameter pulleys 21 and 22 and constant speed ratio pulleys 23 and 24 are arranged, and belts 18 and 19 constitute a two-stage belt transmission,
It is housed in an airtight housing chamber 20 formed by a circular box-shaped airtight frame 14 and a lid 15 . Variable diameter pulleys 21 and 22 are fixed pulleys 21a and 22a and sliding pulley 2, respectively.
It is composed of 1b and 22b. Intermediate shaft 1
2 is supported by a holding body 25, and on the other hand, this holding body 25 has fixed arms 29 extending in three directions.
a, 29b and 29c protrude, each having an elongated hole, and are fixed by bolts or nuts corresponding to the three standing stands 26a, 26b and 26c standing upright from the protruding bottom 14c of the frame 14. Furthermore, the input and output shafts 11 and 12 are supported by flanges 16 and 17, respectively.

On the other hand, as shown in FIG. 2, a blower heat insulating device 30 is provided on the inner wall of one side wall portion 14a of the box-shaped frame body 14 and protrudes outside the frame body, and a blower device, that is, a Sirotsko cooling blower 31 is attached thereto. There is. Although a centrifugal blower device is shown here,
An axial blower device may be used as long as a high static pressure can be maintained in the room 20. The rotary shaft 32 of the blower 31 is also equipped with a small diameter pulley 33, and a round belt 41 is wound around the large diameter pulley 42 provided above the drive side fixed pulley 21a. It is configured to be able to rotate at approximately 3000 rpm or more depending on the power.

On the other hand, a pilot control section 35 for controlling the drive-side variable pulley is installed on the other side wall 14b of the box-shaped frame 14, and a recycling motor 36 with a built-in gear reducer is fixed to a mounting base 37. The motor output is transmitted to the variable pulley 21 via the transmission 38.
It is connected to a connecting means 39 assembled to the. This reversible motor 36 performs speed change control.

Furthermore, a support arm 5 of a tension pulley 54 is attached to the column 52 that stands upright from the freewheel-shaped protruding bottom portion 14c.
3 is provided, and a spring or coil spring 55 provided coaxially with the pressing shaft 56 presses the support arm 53, thereby pressing the pulley 54 against the back of the second stage belt 19. As will be described later, the pressing force exerted by the coil spring 57 is adjusted by rotating the screw 57.

Next, a holder 25 is integrally assembled in advance in the center of the intermediate shaft 12, to which the variable driven pulley 22 is attached to the upper end and the small diameter pulley 24 is attached to the lower end, and this integral assembly A can be removed from the semicircular opening 14d provided on the right side of the housing 10. In addition, in order to adjust the distance between the input/output shafts 11 and 13 and the intermediate shaft 12 when this assembly A is installed, a take-up mechanism is provided at the end of the protruding bottom portion 14c of the housing 10. There is an upright adjustment column 60 and a bolt 61, and the bolt 61 is screwed into a screw hole 62 provided on the back surface of the support 25 to enable manual take-up.

FIG. 3 shows a partially cutaway perspective view of the lower belt tension adjustment section 50 shown in FIG. 2. FIG. Frame body 14
A support arm 52 is fixed upright to the bottom flange portion 14h of the support arm 52, and a support arm 53 having an L-shaped support portion 53a and an arm portion 53b is supported thereon. An engaging portion 53c extends from the arm portion 53b, and is pivotally engaged with one end of the indicating shaft 56. a locking plate 58 adjacent to the pivot portion of the indicator shaft 56 and assembled integrally with the indicator shaft 56;
Adjustment nipple 5 integrally molded with bolt portion 57a
A coil spring 55 is installed between one end of the coil spring 7 and one end of the coil spring 55. The bolt portion 57a of the adjustment nipple 57 is exposed from the tip of the protruding adjustment portion 14g of the frame body 14, so that the tension can be adjusted from the outside of the frame body, and a tapered through hole is provided inside the adjustment nipple 57. The other end of the indicator shaft 56 is connected to the bolt portion 5.
The belt tension can be visually checked by the positional relationship between the nipple and the scale further exposed from the indicator shaft 56 on the side circumferential surface of the indicator shaft 56.

With such a configuration, the intermediate shaft assembly A including the driven pulley 22, the driving pulley 24, and the holder 25 can be attached or detached from within the frame 14 by simply removing a nut during maintenance. However, when newly installing the belt or correcting the elongation of the belt, it is necessary to balance the respective tensions of the upper and lower belts 18 and 19, but in this case, in the embodiment, first the upper belt 18 is First by take-up equipment. As a result, the input/output shaft 11
Once the positions of the intermediate shafts 13 and 13 are determined, the intermediate shaft holder 25 is fixed to the stand with a nut to prevent unexpected abnormal vibrations from occurring in the belt, and then the tension on the lower belt 19 is fixed. The tension adjustment device 50
This is done by.

[Other Examples]

Although the tension adjustment device of the above embodiment is applied to a two-stage power transmission device, it can also be applied to a normal one-stage reduction type belt power transmission device because it has a structure that can be applied independently to a lower-stage reduction gear. is clear.

〔Effect of the invention〕

According to the present invention, the housing that houses the belt power transmission device is kept in a sealed state, and the tension force of the belt is reduced by operating the nipple protruding from the indoor to the outdoor on the wall of the housing on the outdoor side. It has the advantage that it can be adjusted and that the nipple can be operated while constantly visually observing the tension force on the belt by means of a pressing force indicating shaft that passes through the nipple during the operation. As a result, it is possible to absorb the elongation of the belt that occurs when an overload occurs on the belt, and to ensure the optimum tension force that allows stable torque transmission at all times, extremely quickly and without having to open the maintenance cover of the belt transmission device. Since it can be operated, it is extremely advantageous when performing maintenance in hazardous locations.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a power transmission device using a tension adjustment device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of the power transmission device taken along the line - in FIG. 1. FIG. 3 shows a partial perspective view of a tension adjustment device used in the transmission device. In the figure, 10...housing, 11, 12 and 13...input shaft, intermediate shaft and output shaft, 14...
Frame body, 14a and 14b...Side wall portion, 14c...
...Protruding bottom part, 14d...Opening part, 15...Lid body,
30...Heat insulation device, 35...Control device, 50...
Tension adjustment device, 60... Take-up device, A...
...Intermediate shaft assembly, B...First stage transmission section, C...Second transmission section.

Claims (1)

[Claims] 1. A belt power transmission that has a tension pulley on the indoor side of a closed housing that houses a belt power transmission device, a lever for pivotally supporting this pulley, and a spring that applies back pressure to this lever. In the tension adjustment device of the device, a nipple is arranged on the wall surface of the housing to be in contact with the spring on the indoor side and to be able to adjust the pressing force by the spring on the outdoor side, and a central through hole made in the nipple is provided. and an indicator shaft for the pressing force, the free end of which penetrates toward the outdoor side, and the nipple can be operated while the indicator shaft is displayed outdoors. tension adjustment device. 2. The tension adjustment device for a belt power transmission device according to claim 1, wherein a scale means for measuring the amount of back pressure applied to the belt is provided on the free end of the indicator shaft.