JPH036299Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a pulley mounting structure for a washing machine in which a pulley is mounted on the rotating shaft of a rotor blade.

[Conventional technology]

The washing machine generates water flow in the washing tank by rotating rotary blades installed at the bottom of the washing tank. In such a washing machine, as shown in FIG. 3, a rotating shaft 1 having rotary blades 7 attached to its upper end projects downward through a cylindrical bearing 5 attached to the lower surface of the bottom of a washing tank 4. Washable motor (not shown)
A pulley 2 that decelerates and transmits the rotation is fixed.

The bearing 5 is fastened to the bottom of the washing tank 4 with a bearing nut 6.

Further, the rotation of the washing motor is transmitted to the pulley 2 by a V-belt 8.

Then, as shown in FIG. 4, a screw hole 1b into which the mounting screw 3 is screwed is bored in the lower part of the rotating shaft 1, perpendicular to the axial direction, and the boss part 2 of the pulley 2
In a, a round hole 2c through which the rotating shaft 1 passes vertically is bored vertically, and a through hole 2b through which the mounting bolt 3 passes is bored horizontally at right angles to the round hole 2c.

Then, insert the lower part of the rotating shaft 1 into the round hole 2c,
A mounting bolt 3 is screwed into the screw hole 1b through the through hole 2b and is tightened and fixed.

[Problem that the invention attempts to solve]

In the conventional fixing structure of the pulley 2 using the mounting bolt 3, tensile stress caused by tightening and shear stress caused by the torque transmitted to the pulley 2 act on the threaded valley of the mounting bolt 3, resulting in stress concentration. Therefore, bolts made of general steel may cause damage during operation of the washing motor, and to withstand this, it is necessary to increase the diameter of the rotating shaft 1 as much as possible and the diameter of the mounting bolt 3, or to use bolts made of chrome-molybdenum steel, etc. The strength had to be increased by using special steel mounting bolts, which resulted in extremely high costs.

The purpose of the present invention is to eliminate the disadvantages of the conventional example,
By reducing the stress acting on the mounting bolts, damage to the mounting bolts can be prevented and the durability of the bolts can be extended, and the diameters of the mounting bolts and rotating shaft can be reduced, and the material of the mounting bolts can be made from ordinary steel. An object of the present invention is to provide a pulley mounting structure for a washing machine which leads to a reduction in manufacturing costs.

[Means for solving problems]

In order to achieve the above object, the present invention forms the lower end of the rotating shaft of the rotor blade into a prismatic body with a horizontally rectangular cross section,
Further, a screw hole perpendicular to the axial direction is provided above the square prism, and a square hole that matches the prism is provided at the bottom of the boss part of the pulley, and the prism of the rotating shaft is inserted into the square hole. The gist is that the mounting bolts are inserted and fitted into each other, and then inserted into the bolt through holes drilled laterally in the boss portion of the pulley and into the threaded holes of the rotating shaft, and then tightened.

[Effect]

According to the present invention, the prismatic body formed at the lower end of the rotating shaft is fitted into the square hole drilled in the boss of the pulley, so that the rotating shaft can be washed at this part, and the large amount of torque transmitted from the motor can be Only a small torque is applied to the mounting bolt, which passes through the bolt through hole drilled horizontally in the boss part of the pulley and the screw hole drilled perpendicularly to the axial direction of the rotating shaft. The main role of the bolt is to support it in the thrust direction, reducing the load.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Fig. 1 is a longitudinal sectional front view showing the main parts of the pulley mounting structure of the washing machine of the present invention, Fig. 2 is an exploded perspective view of the same, and the same components as Figs. 3 and 4 showing the conventional example refer to the same reference. The symbols are attached.

In the figure, reference numeral 1 denotes a rotating shaft protruding from the bottom surface of the washing tank with rotary blades (not shown) installed at the bottom of the washing tank. This is the same as in the conventional example in that the lower part of the rotary shaft 1 is inserted into the round hole 2c of the boss part 2a of the pulley 2.

The lower end of the rotating embodiment 1 has a cross section with a vertical width of A, for example.
It was formed into a rectangular prism 1a with a vertically long rectangle larger than the width B.

Further, a screw hole 1b is bored in the cylindrical portion above the quadrangular prism 1a so as to be perpendicular to the axial direction.

It is desirable that this screw hole 1b be provided parallel to the longer width A of the rectangular prism 1a. 9 in the figure is a chamfer formed around the opening of the screw hole 1b.

On the other hand, a round hole 2c (see FIG. 1) is provided in the boss portion 2a of the pulley 2, into which the cylindrical portion of the rotating shaft 1 is inserted;
Further, a square hole 2d having a shape that matches the square prism 1a of the rotation shaft 1 is provided below so as to be continuous therewith, and a mounting bolt 3 is provided perpendicularly to the round hole 2c.
A bolt through hole 2b into which the bolt is inserted was drilled horizontally.

In this way, in order to fix the pulley 2 to the rotating shaft 1, first fix the square prism 1a at the lower end of the rotating shaft 1.
is inserted into the square hole 2d of the pulley 2 and fitted, and the mounting bolt 3 is passed through the bolt through hole 2b of the pulley 2 and further screwed into the screw hole 1b of the rotating shaft 1 to be tightened and fixed.

Furthermore, as is clear from what has been said above,
When attaching the pulley 2 to the square column 1a of the rotating shaft 1, since the cross section of the square column 1a and the square hole 2d of the pulley 2 are vertically elongated squares, by matching them, the bolt of the pulley 2 can be inserted. Since the hole 2b and the screw hole 1b of the rotating shaft 1 naturally match, it is possible to prevent incorrect installation, and the pulley 2
The installation work efficiency can be improved.

In the embodiment described above, the lower end of the rotating shaft 1 and the hole on the pulley 2 side into which it is fitted are square, but
It is also possible to use other polygons such as a horizontally elongated modified hexagon or an octagon.

Next, regarding the operation, when the washing motor is in operation, the rotation of the washing motor is transmitted to the pulley 2 via the V-belt, and the rotational torque is transmitted to the boss portion 2a via the square prism 1a of the rotating shaft 1. The torque is transmitted to the lower square hole 2d, and this portion receives the torque applied to the mounting bolt 3 in a distributed manner.

As a result, the shear stress acting on the threaded valley of the mounting bolt 3 is several steps smaller than that of the conventional pulley mounting structure, and the main role of the mounting bolt 3 is to prevent the pulley 2 from coming off in the thrust direction. Even bolts made of small materials can maintain strength and durability.

[Effect of idea]

As mentioned above, in the pulley mounting structure of the washing machine of the present invention, most of the torque from the washing motor is received by the prismatic body at the lower end of the rotating shaft, and only a small torque is applied to the mounting bolt. Therefore, the diameter of the rotating shaft can be made small. In addition, the mounting bolts can be made of inexpensive general steel, and the cost reduction effect is extremely large.

In this way, the pulley mounting structure is strong and reliable, and it also has excellent assembly workability such as easy positioning.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional front view of the main parts showing one embodiment of the pulley mounting structure of the washing machine of the present invention, Fig. 2 is an exploded perspective view of the same main parts, and Fig. 3 is a longitudinal sectional front view showing the conventional pulley mounting structure. FIG. 4 is a longitudinal sectional front view of the main parts of the same. 1...Rotating shaft, 1a...square prism, 1b...screw hole, 2...pulley, 2a...boss part, 2b...
...Bolt through hole, 2c...Round hole, 2d...Square hole, 3...Mounting bolt, 4...Washing tank, 5...
Bearing, 6...Bearing nut, 7...Rotor blade, 8...
V-belt, 9... Chamfered portion.

Claims (1)

[Scope of utility model registration request] The lower end of the rotating shaft of the rotor blade is formed into a prismatic body with a horizontally rectangular cross section, and a screw hole is bored above the prismatic body perpendicular to the axial direction, while the prismatic body is formed at the bottom of the boss portion of the pulley. Provide a square hole that matches the square hole, insert and fit the prismatic body of the rotating shaft into the square hole, and insert the mounting bolt into the bolt through hole drilled horizontally in the boss part of the pulley and the threaded hole on the rotating shaft to screw the screw. A washing machine pulley mounting structure characterized by a tightened structure.