JPH0746048Y2 - Drainage tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a drainage tube for a rotating electric machine such as an electric motor or a generator.

[Prior Art] Generally, in rotary electric machines such as electric motors and generators, a drainage hole is provided in the bottom of the housing. However, in a starter motor mounted on a vehicle, water is received from below the vehicle body. Water may leak from the vent hole.

Therefore, Japanese Patent Laid-Open No. 63-240345 discloses a drainage tube that prevents water from entering through the drainage hole.

The water draining tube includes a tubular portion whose front end opening is formed as a drainage port, and a first projecting portion extending toward the center of the tubular portion on the inner peripheral surface of the tubular portion and the first projecting portion. A second projecting portion extending toward the center of the tubular portion is provided on the side facing the first projecting portion in the radial direction closer to the tip end.

Then, when water is received from below the vehicle body, the second projecting portion formed in a thin shape is pushed toward the first projecting portion side by water pressure, and the tip of the second projecting portion makes the first projecting portion project. By contacting the installation portion and covering the water inflow passage, water infiltration is prevented.

[Problems to be solved by the invention] However, in the water draining tube, when the second projecting portion receives continuous direct water hitting, the thin wall portion of the second projecting portion is flexible and easily deformed. There was a possibility that it would be deformed excessively by the force of. Therefore, in the conventional drainage tube, the second
When the projecting portion receives continuous direct water hit, and the thin portion of the second projecting portion moves above the first projecting portion and above the first projecting portion, the water intrusion passage is opened. Therefore, there was a problem of flooding inside the product.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a drainage tube capable of reliably preventing water from entering the inside of a product having a drainage hole.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention comprises a flexible tubular body, and a tip surface in which the tip opening of the tubular body is closed in a semicircular shape,
At the tip end of the tubular body and on the side facing the tip end surface in the radial direction, it is provided so as to project from the inner peripheral surface of the tubular body toward the center direction and is inclined toward the tip end direction of the tubular body. And a protruding portion provided on the cylindrical body, and a slit is formed in the cylindrical body on a side opposite to the distal end surface in the radial direction of the cylindrical body from a distal end opening portion of the cylindrical body to the protruding portion. The technical means is that the tip end surface and the protruding portion are provided in such a size that they overlap each other when viewed in the axial direction.

[Operation] In the water draining tube of the present invention having the above-mentioned configuration, the opening of the cylindrical body is closed in a semicircular shape by the tip surface, and the projecting portion is located above the opening to the tip side of the cylindrical body. It is provided so as to be inclined, and the tip end surface and the projecting portion overlap each other when viewed in the axial direction.

Therefore, even when the direct hit water is received from below the opening, the direct hit water that has entered the tubular body through the opening hits the protruding portion in the slit direction and is drained while opening the slit.

Further, when the direct hit water is received obliquely from below toward the slit side, the water pressure of the direct hit water deforms the tubular body so that the slit is closed, so that it is possible to prevent the direct hit water from flooding into the tubular body. Even when the direct hitting water enters from the gap of the closed slit, it does not hit the projecting portion located above the slit and enter the upper inside of the tubular body.

On the other hand, when the water is directly hit from the outside of the tip surface, the water directly hits the tip surface and scatters to the outside of the cylinder without entering the inside of the cylinder.

[Advantages of the Invention] The water draining tube of the present invention having the above-mentioned action closes the opening of the cylindrical body in a semicircular shape, and provides a projecting portion inclined toward the tip side above the opening, and further opening the opening. By forming the slit from the to the projecting portion, it is possible to reliably prevent water from entering the upper part of the tubular body regardless of the direction in which the water is directly hit.

[Embodiment] Next, a drainage tube of the present invention will be described based on an embodiment shown in the drawings.

FIG. 1 is a vertical cross-sectional view of a drainage tube.

The drainage tube 1 of the present embodiment is a drainage hole (not shown) provided at the bottom of the starter housing in order to discharge water accumulated in the starter due to dew condensation and to supply air into the starter housing. Attach it to and use it.

This drainage tube 1 is provided with a tubular body 2 as a drainage passage, and a tip end opening portion of the tubular body 2 is formed as a drainage port 2a and a rear end opening portion is formed as a mounting portion 2b to a drainage hole. Has been done.

The tip end (lower end in FIG. 1) of the cylindrical body 2 closes the opening in a semi-circular shape and is inclined (downward in FIG. 1) with respect to the center direction of the cylindrical body 2 (in the present invention). The tip surface 3 is formed.

The tip surface of the inclined surface 3 has a size exceeding the center line of the cylindrical body 2.

Therefore, the drainage port 2a is formed only on one side (right side in FIG. 1) from the center of the tubular body 2, and the opening area thereof is as shown in FIG.
As shown in the view A), the size is half or less of the cross-sectional area of the cylindrical body 2.

Further, inside the tubular body 2, a plurality (three in the present embodiment) of a semicircular shape protruding from the inner peripheral surface of the tubular body 2 toward the center thereof are provided.
The protruding portions 4 to 6 are formed.

These projecting portions 4 to 6 are respectively provided on the tip end side of the tubular body 2 by a predetermined angle (acute angle), and the tip portions thereof are formed in a size exceeding the center line of the tubular body 2. ing.

The protrusions 4 to 6 are provided at regular intervals in the up-down direction of the tubular body 2, are disposed on the sides of the tubular body 2 that are alternately opposed to each other in the radial direction, and are located at the bottom. 6 is provided on the side facing the inclined surface 3. By providing these projecting portions 4 to 6, the drainage passage of the cylindrical body 2 is formed in a labyrinth shape to prevent water from entering.

The drainage tube 1 is made by pouring synthetic rubber into a mold and integrally molded, and has an appropriate rubber hardness so that the protruding portions 4 to 6 and the inclined surface 3 are not torn off during the mold removal. Have.

As shown in FIG. 2, the cylindrical body 2 has a slit 7 formed on the side opposite to the inclined surface 3 in the radial direction between the tip of the cylindrical body 2 and the lowermost protruding portion 6.

The width of the slit 7 is determined in consideration of the rubber hardness,
For example, when the rubber hardness is 40, it has a width of 1 mm.

The operation of the water draining tube 1 of this embodiment will be described with reference to the drawings.

For example, as shown in FIG. 4, when the water is directly hit from below the cylinder 2.

The direct water hitting the inside of the cylinder 2 through the drainage port 2a hits the lowest projecting portion 6 and flows toward the slit 7 and does not enter the inside of the upper part of the cylinder 2 as shown in FIG. Drain while pushing 7 open.

As shown in FIG. 6, when water is directly hit from the slit 7 side.

The tubular body 2 made of rubber is deformed so as to close the slit 7 as shown in FIG. 7 while being pushed inward by the force of the direct hitting water.

Therefore, it is possible to prevent the direct hitting water from entering the cylindrical body 2. Even if the direct hit water enters from the gap of the closed slit 7, it does not hit the protruding portion 6 located above the slit 7 and enter the inside of the upper portion of the tubular body 2.

Further, as shown in FIG. 8, when the water is directly hit from the outside of the inclined surface 3.

The direct hitting water does not collide with the inclined surface 3 as it is and does not enter the inside of the cylindrical body 2, but scatters to the outside of the cylindrical body 2.

In this way, it is possible to prevent water from entering the upper part of the tubular body 2 regardless of the direction in which the drainage tube 1 receives water. Therefore, by attaching the drainage tube 1 of this embodiment to the starter. Even when water is received from the lower side of the vehicle body while traveling or washing the vehicle, it is possible to prevent water from entering the starter.

(Modification) In this embodiment, the drainage tube 1 is used for the starter, but it may be used for an electric motor other than the starter, a generator, or the like.

The slit 7 is not limited to one place and may be provided in two or more places.

[Brief description of drawings]

Fig. 1 is a vertical cross-sectional view of the drainage tube, Fig. 2 is a side view of the drainage tube, Fig. 3 is a view of Fig. 1A, and Figs. 4 and 5 are direct hit water from below the drainage port. Fig. 6 and Fig. 7 are the state diagrams of the water draining tube when it receives direct water from the slit side, and Fig. 8 shows the state of the water draining tube when it receives direct water from the inclined surface. It is a state diagram of the drainage tube in the case. In the drawing, 1 ... Drainage tube, 2 ... Cylindrical body 3 ... Inclined surface (tip surface), 4-6 ...

Claims (1)

[Scope of utility model registration request] 1. A flexible cylinder, (b) a front end surface obtained by closing a front end opening of the cylinder in a semicircular shape, and (c) a front end of the cylinder, and On a side facing the tip end surface in the radial direction, a projection portion is provided which protrudes from the inner peripheral surface of the tubular body toward the center direction and is provided so as to be inclined toward the tip end direction of the tubular body. A slit is formed in the cylindrical body on a side opposite to the distal end surface in the radial direction of the cylindrical body from a distal end opening portion of the cylindrical body to the projecting portion, and the distal end surface and the projecting portion are provided. The part is a drainage tube characterized in that it is provided in such a size that it overlaps when viewed in the axial direction.