EP1985842A1

EP1985842A1 - Starter

Info

Publication number: EP1985842A1
Application number: EP08007114A
Authority: EP
Inventors: Yoshinori Yamaguchi
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2007-04-27
Filing date: 2008-04-10
Publication date: 2008-10-29
Anticipated expiration: 2028-04-10
Also published as: JP4240133B2; EP1985842B1; JP2008274830A

Abstract

In the starter (1), the inner peripheral hollow part of an electrical magnetic coil (15) in the electromagnetic relay (6) is covered with the sealing cap (17) made of rubber. The ventilation hole (17a) is formed in the sealing cap (17). The inside of the electromagnetic relay (6) communicates with outside atmosphere through the ventilation room (22) and the open passage (23) formed in the housing (7) and the ventilation hole (17a). The sealing cap (17) is positioned toward the circumferential direction by the positioning means (7c, 17b) formed in the housing (7) and the sealing cap (17) so that the ventilation hole (17a) is placed at an upper part to the ventilation room (22) when the starter (1) is mounted to a vehicle. This structure protects the inside of the electromagnetic relay (6) from water invasion through the ventilation hole (17a) even if water enters the ventilation room (22).

Description

BACKGROUND OF THE INVENTION

1. Field of the invention

The present invention relates to a starter of a constant meshing type in which the pinion gear is in constant meshing the ring gear of an internal combustion engine of a vehicle.

2. Description of the Related Art

Japanese patent laid open publication No. JP 2006-207573 has disclosed a conventional starter. Such a conventional starter is comprised of a motor that generates rotation power, an electromagnetic relay that performs ON/OFF control of a current to be supplied to the motor, a pinion gear that transmits a driving torque of the motor to the ring gear of an internal combustion engine. In the above starter disclosed in JP 2006-207573 , the pinion gear is in constant mesh with the ring gear.
Because the starter mounted to a motor vehicle is often covered with water when the vehicle drives, it is better to use a closed-type electromagnetic relay which is closed when compared with an open-type electromagnetic relay. That is, when the open-type electromagnetic relay in the starter is covered with water, there is a high possibility that water enters into the inside of the open-type electromagnetic relay, and as a result, rusts and freezes the electrical contacts of the electromagnetic relay.
On the other hand, there is almost no possibility of rusting or freezing the electrical contacts of the closed-type electromagnetic relay in the starter because of having a low possibility of water invasion.
However, such a closed-type electromagnetic relay is requested to have a strong sealing structure to withstand the inside pressure of the electromagnetic relay because a high inside pressure is generated in the closed-type electromagnetic relay when the plunger moves because when the plunger moves, great pressure is generated in the closed type electromagnetic relay. Furthermore, the closed-type electromagnet relay needs to perform the additional step (for example, a drying step) in order to completely remove water from the closed-type electromagnetic relay during its assembling step. Accordingly, because the starter with the closed-type electromagnetic relay needs to perform this complicated process, its manufacturing cost is increased when compared with that of the starter having the open-type electromagnetic relay.
In order to decreasing the manufacturing cost of the starter with the closed-type electromagnetic relay, there is a starter with an open passage in the housing to which the motor and the closed-type electromagnetic relay are fixed. In the starter, the inside of the closed-type electromagnetic relay communicates with the outside atmosphere through an open passage, in order to drain water from the inside of the closed-type electromagnetic relay to the outside.
However, if the vehicle is covered with a lot of water and the water is accumulated in the transmission case of the vehicle when the ring gear operates, the water would enter the inside of the closed-type electromagnetic relay through the open passage formed in the housing.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a starter with an electromagnetic relay with an improved water-proof function.
To achieve the above purposes, the present invention provides a starter (1) that is comprised mainly of a motor (2), an output shaft (4), a pinion gear (5), an electromagnetic relay (6), and a housing (7). The motor (2) generates rotation power when receiving electric power. The output shaft (4) of the motor (2) rotates by the rotation power. The pinion gear (5) is placed on the output shaft (4) and is always engaged with a ring gear (13) of an internal combustion engine. The pinion gear (5) transmits a driving torque of the motor (2) in the starter (1) to the ring gear (13). Electrical contacts of a motor circuit of the motor (2) turns ON and OFF when a plunger (16) in the electromagnetic relay (6) is attracted and released (or returned to its original position). The motor (2) and the electromagnetic relay (6) are fixed to the housing (7). The housing (7) has a ventilation room (22) and an open passage (23). That is, the ventilation room (22) is formed in the housing (7) at a rear side of the plunger (16) in the electromagnet relay (6) assembled in the starter (1). The ventilation room (22) in communication with the inside of the electrical magnet relay (6) through a ventilation hole (17a, 17a-1, 17a-2, 17a-3) formed in a sealing cap (17, 17-1, 17-2, 17-3). The ventilation room (22) communicates with the outside atmosphere through the open passage (23). The housing-side part of the electromagnetic relay (6) is covered with the sealing cap (17, 17-1, 17-2, 17-3). The sealing cap (17, 17-1, 17-2, 17-3) has the ventilation hole (17a, 17a-1, 17a-2, 17a-3) to be placed in a ceiling-direction side of a vehicle, to which the starter (1) is mounted, when compared with the position of the ventilation room (22).
The electromagnetic relay (6) communicates with the outside atmosphere through the ventilation hole (17a, 17a-1, 17a-2, 17a-3), the ventilation room (22), and the open passage (23).
The electromagnet relay (6) does not need to have a strong sealing structure capable of withstanding the inside pressure of the electromagnetic relay (6) because the electromagnetic relay (6) communicates with the outside atmosphere through the ventilation hole (17a, 17a-1, 17a-2, 17a-3) formed in the sealing cap (17, 17-1, 17-2, 17-3), the ventilation room (22), and the open passage (23) formed in the housing (7). Furthermore, because the starter (1) with the electromagnetic relay (6) does not need to perform any water drain during the electromagnetic relay (6) assembling, it is possible to decrease the manufacturing cost of the starter (1) when compared with that for the starter with a conventional closed-type electromagnetic relay.
Still further, the sealing cap (17, 17-1, 17-2, 17-3) is so placed that the ventilation hole (17a, 17a-1, 17a-2, 17a-3) is placed at an upper position when compared with the position of the ventilation room (22) when the starter (1) is mounted to a vehicle. Even if water enters the inside of the ventilation room (22) from the outside of the starter (1) through the open passage (23), the water can not reach the inside of the electromagnetic relay (6) through the ventilation hole (17a, 17a-1, 17a-2, 17a-3). This structure of the starter (1) according to the present invention can provide high-water proof function when the starter (1) is mounted to a vehicle which is often covered with water.
In the starter (1) according to another aspect of the present invention, the open passage (23) has open parts (23a, 23b) at one end and the other end thereof. The open part (23b) communicating with the ventilation room (22) would be placed at an upper side in the vehicle, to which the starter (1) is mounted, when compared with the position of the open part (23a) that communicates with the outside atmosphere.
The open parts (23a, 23b) of the open passage (23) formed in the housing (7) have a difference in position. Even if water enters the inside of the open passage (23) through the open part (23b) communicating with the outside atmosphere, this structure can protect the open part (23a) at the ventilation room (22) side from water invasion. Still further, even if water in the open passage (23) enters the inside of the ventilation room (22), it is possible to easily drain the water through the open passage (23) because the open part (23a) is formed at the bottom part of the ventilation room (22).
In the starter (1) according to another aspect of the present invention, the sealing cap (17, 17-1, 17-2, 17-3) is positioned so that the ventilation hole (17a, 17a-1, 17a-2, 17a-3) is positioned at the upper part by positioning means (7c, 17b) formed in the housing (7) and the sealing cap (17, 17-1, 17-2, 17-3) when compared with the position of the ventilation room (22).
Because the ventilation hole (17a, 17a-1, 17a-2, 17a-3) can be easily and certainly positioned at the upper part when compared with the position of the ventilation room (22) in the sealing direction of a vehicle to which the starter (1) is mounted, the present invention can provide both a highly reliable and highly waterproof starter.
In the starter (1) according to another aspect of the present invention, the positioning means is composed of a convex part (17b) or a concave part formed in the sealing cap (17, 17-1, 17-2, 17-3) and a concave part (7c) or a convex part formed in the housing (7), and the sealing cap (17, 17-1, 17-2, 17-3) is positioned by mating the positioning means having the convex part (17b) and the concave part (7c). The present invention can provide the starter (1) with the electromagnetic relay (6) and the sealing cap (17, 17-1, 17-2, 17-3) with the positioning means with a simple structure using a combination of the concave part (7c) and the convex part (17b).
In the starter (1) according to another aspect of the present invention, the ventilation hole (17a-1, 17a-2, and 17a-3) is formed with a different shape. Because the ventilation hole (17a-1, 17a-2, and 17a-3) is formed in a curved shape (17a-1), a crank shape (17a-2), and a labyrinthine structure in which the ventilation hole (17a-3) has a crank shape (17a-3) with obstacle walls therein, it is possible to protect the electromagnetic relay (6) from direct water-invasion through the ventilation hole (17a-1, 17a-2, and 17a-3). This structure of the ventilation hole can enhance the water proof function of the electromagnetic relay (6) in the starter (1).

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred, non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which:

FIG.1 is a side view showing the entire configuration of the starter having the electromagnetic relay of an improved water-proof function according to the first embodiment of the present invention;
FIG. 2 is a front view of the housing of the starter shown in FIG. 1, observed from the rear side of an internal combustion engine mounted to a vehicle;
FIG. 3A is a cross section of the sealing cap that covers and seals the electromagnetic relay of the starter according to the first embodiment shown in FIG. 1;
FIG. 3B is a plan view showing the sealing cap observed from the plunger side in the electromagnetic relay of the starter shown in FIG. 1; and
FIG. 4A to FIG. 4C, each is a cross section showing a modification of the ventilation hole formed in the sealing cap for the electromagnetic relay of the starter according to the second embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, various embodiments of the present invention will be described with reference to the accompanying drawings. In the following description of the various embodiments, like reference characters or numerals designate like or equivalent component parts throughout the several diagrams.

First embodiment

A description will be given of the starter according to the first embodiment of the present invention with reference to FIG. 1, FIG. 2, FIG. 3A, and FIG. 3B.
FIG.1 is a side view showing the entire configuration of the starter 1 having the electromagnetic relay 6 of an improved water-proof function according to the first embodiment of the present invention. FIG. 2 is a front view of the housing 7 of the starter 1 shown in FIG. 1, observed from the rear side of an internal combustion engine mounted to a vehicle. FIG. 3A is a cross section of the sealing cap 17 that covers and seals the electromagnetic relay 6 in the starter 1 according to the first embodiment shown in FIG. 1. FIG. 3B is a plan view showing the sealing cap 17, observed from the plunger 16 side in the electromagnetic relay 6 of the starter 1 shown in FIG. 1.
As shown in FIG. 1, the starter 1 is comprised mainly of the motor 2, the reduction device 3, the output shaft 4, the pinion gear 5, the shock absorbing device, the electromagnetic relay 6, and the housing 7.
The motor 2 generates rotation power and outputs driving torque. The reduction device 3 is capable of reducing the rotation of the motor 2. The output shaft 4 transmits the driving torque of the motor 2 to the ring gear 13 of an internal combustion engine (not shown). The pinion gear 5 is supported by the output shaft 5. The shock absorbing device (will be explained later) is capable of absorbing shock applied to the driving mechanism of the starter 1 through the pinion gear 5. The electromagnetic relay 6 turns the electrical contacts placed in the motor circuit ON and OFF for the motor 2. The motor 2 and the electromagnetic relay 6 are fixed to the housing 7.
The motor 2 is a well-known DC electric motor. When the main electrical contact is closed by the electromagnetic relay 6, the motor 2 receives electric power of the battery (not shown) mounted to the vehicle. The armature (not shown) built in the motor 2 generates rotation power. The motor 2 is tightly fixed to the housing 7 by through bolts 8.
The reduction device 3 is an epicycle reduction gear composed of planet gears capable of decreasing the rotation speed transmitted from the motor 2 through the armature shaft 9. The decreased rotation speed obtained through the planet gear 10 is transmitted to the output shaft 4.
The output shaft 4 and the armature shaft 9 are placed on the same axis. The end part of the output shaft 4, which is the opposite side of the motor 2, is rotatebly supported to the nose section 7a of the housing 7 through the shaft bearing 11.
The other end part of the output shaft 5, which is the same side of the motor 2, is connected to the armature shaft 9 through the reduction device 3.
The pinion gear 5 is rotatably engaged with the outer periphery of the output shaft 4 through the bearing 12. In addition, the pinion gear 5 is always engaged with the ring gear 13 of the internal combustion engine (not shown). The motor torque that is amplified by the reduction device 3 when the internal combustion engine (not shown) starts and the amplified one is transmitted to the ring gear 13.
The shock absorbing device is composed mainly of the shock absorbing member 14 made of rubber or another member placed between the output shaft 4 and the pinion gear 5.
The shock absorbing device is capable of absorbing shock applied to the driving mechanism of the starter 1. For example, the shock absorbing member 14 is elastically compressed when an excess power is applied to the pinion gear 5 through the ring gear 13.
The electromagnetic relay 6 is comprised of the built-in electromagnetic coil 15 and the built-in plunger 16. The electromagnetic coil 15 forms an electromagnet. This electromagnet operates on receiving electric power of the battery (not shown) mounted to a vehicle. The plunger 16 moves on the inner periphery of the electromagnetic coil 15 in its axial direction (toward the right and left directions). When the electric power is supplied to the electromagnetic coil 15, the electromagnet is formed in the electromagnetic coil 15. Thereby, the plunger 16 is forcedly attracted, and the main electrical contact connected to the plunger 16 is electrically closed, namely, turns ON.
When the electric power supply from the battery to the electromagnetic coil 15 is halted, and the attraction force thereby disappears, the plunger 16 is forcedly returned to its original position by the force of a return spring (not shown), and the main electrical contact is thereby open, namely, turns OFF.
As shown in FIG. 1, the electromagnetic relay 6 is placed close to the outside in the radial direction of the motor 2 and fixed to the housing 7 by pairs of bolts and nuts (not shown).
In the electromagnetic relay 6, the inner-peripheral hollow section of the electromagnetic coil 15 is sealed with the sealing cap 17. The inner-peripheral hollow section of the electromagnetic coil 15 opens toward the housing side in the axial direction (toward the left side in FIG. 1).
This sealing cap 17 covers the end part of the plunger 16 which projects toward the housing 7 side from the end surface in the axial direction of the electromagnetic-coil case. This electromagnetic-coil case accommodates the electromagnetic coil 15. The outer peripheral edge part of the sealing cap 17 is supported between the end surface in the axial direction of the electromagnetic-coil case and the housing 7 when the electromagnetic relay 6 is fixed to the housing 7.
This sealing cap 17 has one ventilation hole 17a through which the electromagnetic relay 6 is ventilated (see FIG. 3A and FIG. 3B).
The plate member 18 (see FIG. 1) is placed in the inside of the sealing cap 17. The plunger 16 is returned to its original position by the return spring, and is finally contacted to the plate member 18.
The main electrical contact is composed mainly of the pair of fixed contacts and a movable contact. The pair of fixed contacts (not shown) is connected to the motor circuit through the pair of outer terminals 19 and 20. The movable contact and the plunger 16 move together. The movable contact electrically connects the pair of fixed contacts. That is, the main electrical contact enters the closed state when the movable contact is pushed to the pair of fixed contacts and the fixed contacts are electrically connected through the movable contact. The main electrical contact enters the open state when the movable contact is separated from the pair of fixed contacts and the fixed contacts are electrically disconnected.
The pair of outer terminals is composed of the B terminal 19 and the M terminal 20. The B terminal 19 is electrically connected to the battery plus (+) terminal through a battery cable. The M terminal 20 is electrically connected to the motor lead wire 21 in the motor 2. Those B terminal 19 and the M terminal 20 are fixed to the resin cover 6a of the electromagnetic relay 6.
The housing 7 has a nose part 7a. The nose part 7a is inserted into the internal combustion engine side through an open part formed in the starter attachment wall (for example, the transmission case) placed in the internal combustion engine side.
The pinion gear 5 is accommodated in the inside of the nose part 7a. As shown in FIG. 2, the open part 7b is formed at the ring gear side in the radial direction of the nose part 7a. Through the open part 7b, the pinion gear 5 is engaged with the ring gear 13. That is, the inside of the housing 7 communicates with the outside atmosphere through the open part 7b.
As shown in FIG. 1, the housing 7 has the cylindrical hole, the ventilation room 22, and the open passage 23. The cylindrical hole in the housing 7 has a larger inner radius than the outer radial of the plunger 16. The ventilation room 22 is formed from the bottom part of the cylindrical hole toward the depth direction of the housing 7. Through the open passage 23, the ventilation room 22 communicates with the outside atmosphere through the open passage 23.
The sealing cap 17 is placed in the cylindrical hole in the housing 7. Although the sealing cap 17 separates the electromagnetic relay 6 from the ventilation room 22, the inside of the electromagnetic relay 6 communicated with the ventilation room 22 through the ventilation hole 17a formed in the sealing cap 17.
Specifically, as shown in FIG. 1, the ventilation hole 17a communicates with the communicating room 22a. The communicating room 22a is formed in a part of the ventilation room 22 so that the ventilation room 22 is extended toward the outside of the radial direction thereof. The communicating room 22a is formed in the upper part (, or toward the ceiling direction of the vehicle) of the ventilation room 22.
The sealing cap 17 is also positioned toward the circumferential direction of the sealing cap 17 by the positioning means formed in the housing 7 and the sealing cap 17.
For example, this positioning means is composed mainly of the concave part 7c (see FIG. 2) formed in the housing 7 and the convex part 17b (see FIG. 3) formed at the outer peripheral part of the sealing cap 17. Instead of the concave part 7c and the convex part 17b, it is possible that the convex part is formed in the housing 7 and the concave part is formed at the outer peripheral part of the sealing cap 17.
The concave part 7c and the convex part 17b are engaged together and the sealing cap 17 is positioned at the housing 7 toward the circumferential direction.
As shown in FIG. 2, the open part 23a is placed at a higher position rather than the position of the open part 23b, where the open part 23a communicates with the bottom part of the ventilation room 22, and the open part 23b communicates with the outside atmosphere.
Next, a description will now be given of the operation of the starter 1 according to the first embodiment of the present invention.
The armature of the motor 2 starts to rotate when the electromagnetic relay 6 receives electrical power supplied from the battery (not shown), the main electrical contact is closed (namely, turns ON), and the electrical power is thereby supplied to the motor 2.
The reduction device 3 decreases the rotation speed of the armature of the motor 2, and transmits the rotation power of the armature to the output shaft 4. The rotation power of the motor 2 is then transmitted from the pinion gear 5 to the ring gear 13. The internal combustion engine (not shown) that is cranked to the ring gear 13 starts to rotate by the rotation power.
When the rotation speed of the internal combustion engine exceeds the rotation speed of the starter 1, a one-way clutch (not shown) built in the ring gear 13 starts to race, and the ring gear 13 is separated from the crank shaft of the internal combustion engine. This can avoid the transmission of the rotation speed of the internal combustion engine to the pinion gear 5, and protect the armature of the motor 2 in the starter 1 from over-running.
After the internal combustion engine starts, the rotation speed of the armature in the motor 2 is gradually decreased when the main electrical contact is open (namely, turns OFF), and the electric power supply from the battery to the motor 2 in the starter 1 is halted. Finally, the motor 2 in the starter 1 stops.

(Effects of the starter 1 according to the present invention)

Because the inside of the electromagnetic relay 6 communicates with the outside atmosphere through the ventilation hole 17a formed in the sealing cap 17, the ventilation room 22 and the open passage 23 formed in the housing 7, the starter 1 according to the present invention does not need to have any sealing mechanism capable of resisting the high inside pressure of the electromagnetic relay 6 caused when the plunger 16 moves. Further, because the inside of the electromagnetic relay 6 always communicates with the outside atmosphere, the manufacturing work for the starter 1 according to the present invention does not need to drain water during the electromagnetic relay assembling. As a result, it is possible to decrease the manufacturing cost of the starter 1 with the electromagnetic relay 6 according to the present invention when compared with that of the starter having the conventional closed-type electromagnet relay.
In addition, because the open part 23a is placed at a higher position of the ceiling of a vehicle, to which the starter 1 is mounted, when compared with the open part 23b communicating with the outside atmosphere, it is possible to protect the open part 23a of the open passage 23 at the ventilation room 22 side from water invasion even if water enters in the inside of the open passage 23 through the open part 23b at the outer atmosphere side.
Still further, even if water reaches the ventilation room 22 through the open part 23a of the open passage 23, it is possible to avoid water accumulated in the ventilation room 22 and to easily drain the water to the outside of the starter 1 through the open passage 23 because the open part 23a of the open passage 23 is placed at the bottom side of the ventilation room 22.
Furthermore, the ceiling cap 17 is so placed in the housing 7 that the ventilation hole 17a formed in the sealing cap 17 points toward the ceiling direction of the starter 1 shown in FIG. 1 when compared with the position of the ventilation room 22. In other words, as shown in FIG. 1, because the ventilation hole 17a is placed at the upper part of the ventilation room 22, it is possible to vent water accumulated in the ventilation room 22 to the outside of the starter 1 through the open passage 23. This structure protects the electromagnetic relay 6 from water invasion by the position of the ventilation hole 17a even if water reaches the ventilation room 22. This structure of the starter 1 according to the present invention can maintain a higher water-proof function even if the starter 1 is mounted to a vehicle and the vehicle is always covered with water when wind and rain hit the vehicle.

Second embodiment

A description will be given of the starter according to the second embodiment of the present invention with reference to FIG. 4A, FIG. 4B, and FIG. 4C.
FIG. 4A to FIG. 4C are cross sections showing three different modifications of the ventilation holes 17a-1, 17a-2, 17a-3 formed in the sealing caps 17-1, 17-2, 17-3, respectively. Each sealing cap covers the electromagnetic relay 6 of the starter 1 according to the second embodiment of the present invention.
As shown in FIG. 4A, the ventilation hole 17a-1 of a curved shape is formed in the ceiling cap 17-1.
As shown in FIG. 4B, the ventilation hole 17a-2 of a crank shape without any obstacle wall is formed in the ceiling cap 17-2.
As shown in FIG. 4C, the ventilation hole 17a-3 of a crank shape having obstacle walls therein as a labyrinthine structure is formed in the ceiling cap 17-3.
When compared with the configuration of the ceiling cap 17 shown in FIG. 3A and FIG. 3B that is used in the starter 1 according to the first embodiment, the ceiling caps 17-1, 17-2, and 17-3 used in the starter according to the second embodiment can protect the electromagnetic relay 6 from direct invasion of water. This structure of the ceiling caps 17-1, 17-2, and 17-3 can increase the water proof function.
While specific embodiments of the present invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limited to the scope of the present invention which is to be given the full breadth of the following claims and all equivalent thereof.

Claims

A starter (1) comprising:
a motor (2) that generates rotation power;

an output shaft (4) of the motor (2) that rotates by the rotation power;

a pinion gear (5) that is placed on the output shaft (4) and is always engaged with a ring gear (13) of an internal combustion engine, and transmits a driving torque of the motor (2) to the ring gear (13);

an electromagnetic relay (6) having a plunger (16) by which electrical contacts of a motor circuit of the motor (2) turn ON and OFF;

a housing (7), to which the motor (2) and the electromagnetic relay (6) are fixed, having a ventilation room (22) and an open passage (23), where the ventilation room (22) is formed in the housing (7) at a rear side of the plunger (16), and the ventilation room (22) is joined to an inside of the electrical magnet relay (6) through a ventilation hole (17a, 17a-1, 17a-2, 17a-3) formed in a sealing cap (17, 17-1, 17-2, 17-3), and the ventilation room (22) is communicated to an outside atmosphere through the open passage (23); and

the sealing cap (17, 17-1, 17-2, 17-3), with which a housing-side part of the electromagnetic relay (6) is covered, having the ventilation hole (17a, 17a-1, 17a-2, 17a-3), to be placed in a ceiling-direction side of a vehicle to which the starter (1) would be mounted, when compared with the position of the ventilation room (22).
The starter (1) as claimed in claim 1, wherein the open passage (23) has open parts (23a, 23b) at one end and the other end thereof, the open part (23b) communicating with the ventilation room (22) would be placed at an upper side in the vehicle, to which the starter (1) is mounted, when compared with the position of the open part (23a) that communicates with the outside atmosphere.
The starter as claimed in claim 1 or 2, wherein the sealing cap (17, 17-1, 17-2, 17-3) is positioned so that the ventilation hole (17a, 17a-1, 17a-2, 17a-3) is positioned at the upper part by positioning means (7c, 17b) formed in the housing (7) and the sealing cap (17, 17-1, 17-2, 17-3) when compared with the position of the ventilation room (22).
The starter as claimed in claim 3, wherein the positioning means is composed of a convex part (17b) or a concave part formed in the sealing cap and a concave part (7c) or a convex part formed in the housing (7), and the sealing cap (17, 17-1, 17-2, 17-3) is positioned by mating the positioning means having the convex part (17b) and the concave part (7c).
The starter as claimed in any one of claims 1 to 4, wherein the ventilation hole (17a-1) of a curved shape is formed in the ceiling cap (17-1).
The starter as claimed in any one of claims 1 to 4, wherein the ventilation hole (17a-2) of a crank shape is formed in the ceiling cap (17-2).
The starter as claimed in any one of claims 1 to 4, wherein the ventilation hole (17a-3) of a labyrinthine structure of a crank shape having obstacle walls therein is formed in the ceiling cap (17-3).