JP2508022B2 - Lubrication mechanism for oil seal of ignition distributor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a lubrication mechanism for an oil seal that prevents oil from entering the ignition distributor.

[Prior Art] Since an ignition distributor handles high voltage inside, it is necessary to prevent oil from entering inside.

Therefore, for example, as shown in FIG. 4, a conventional ignition distributor 2 driven by a camshaft (rotating member) 1 of an engine (internal combustion engine) includes a distributor drive shaft 3 and
An oil seal 5 is provided between the distributor drive shaft 3 and a boss portion (support portion) 4 that supports the distributor drive shaft 3 to prevent oil inside the cam cover 6 from entering the ignition distributor 2.

If the distributor drive shaft 3 rotates in a state where the lip portion 7 of the oil seal 5 does not have an oil film on the sliding surface with the distributor drive shaft 3, the lip portion 7 generates heat and wears.

Therefore, between the distributor drive shaft 3 and the housing 4, two oil passages, one of which is inside the cam cover 6 and the other of which is open to the oil seal 5, so that an oil film is formed on the sliding surface of the oil seal 5. 8 and 9 were formed.

[Problems to be Solved by the Invention] However, while the oil seal 5 is functioning, the two oil passages 8 and 9 form a dead end due to the oil seal 5, so that oil is not supplied to the oil seal 5 Part 7 wears.

When the lip portion 7 of the oil seal 5 wears, the oil seal 5 fails to function and the dead end is released, so that the oil scattered in the cam cover 6 and the oil flowing along the inner wall of the cam cover 6 are released. There was a problem that it would flow into the ignition distributor 2.

The present invention has been made in view of the above circumstances, and an object thereof is to positively supply oil to an oil seal that prevents oil in the cam cover from flowing into the ignition distributor to prevent wear of the oil seal. It is to provide a lubrication mechanism of an oil seal of an ignition distributor which can be prevented.

[Means for Solving the Problems] In order to achieve the above object, the present invention employs the following technical means.

The lubrication mechanism of the oil seal of the ignition distributor has a connecting member for connecting to a rotating member in a case of an internal combustion engine in which oil is scattered, the distributor drive shaft having a smaller diameter than the connecting member, and the distributor drive shaft. The member side is arranged between the boss portion of the housing that supports it through a metal bearing, the distributor drive shaft and the boss portion, and on the side different from the connecting member with respect to the metal bearing. An oil seal, an oil suction port opened between the boss portion and the connecting member, and an oil supply port opened in a space facing the oil seal, and between the metal bearing and the boss portion. An oil supply passage, an oil outlet opening between the boss and the connecting member, and an oil opening in the space An outlet, and an oil discharge passage provided between the metal bearing and the boss.

The surface of the boss portion on the side of the connecting member is provided so that a gap between the boss portion and the connecting member is partially different, and the oil suction port is formed in a portion where a gap between the boss portion and the connecting member is wide. The oil outlet is opened at a portion where the gap between the boss portion and the connecting member is narrow.

[Operation] The oil suction port of the oil supply passage opens in a portion having a wide gap between the supporting portion and the connecting member, and the oil outlet port of the oil discharge passage opens in a portion having a narrow gap between the supporting portion and the connecting member. For this reason, when the connecting member is driven by the rotating member to rotate, a weak negative pressure is generated in a portion having a wide gap where the oil suction port opens, and a strong negative pressure is generated in a portion having a narrow gap opening for the oil outlet. appear.

In this way, a pressure difference occurs between the oil suction port and the oil outflow port. Therefore, the air in the case is sucked into the space facing the oil seal from the oil suction port, and the air sucked in the space is again discharged into the case from the oil outlet.

Along with this air flow, oil scattered in the case and oil flowing along the inner wall of the case are sucked into the oil suction port to lubricate the oil seal. The oil introduced into the space facing the oil seal flows out from the oil outlet along with the flow of air.

EFFECTS OF THE INVENTION According to the present invention, when the rotating member is rotated, oil is always positively supplied to the oil seal, so that an oil film is constantly formed on the sliding surface of the oil seal. It is possible to prevent the oil in the case from flowing into the spark distributor.

An oil supply passage for guiding the oil in the case to the oil seal and an oil discharge passage for returning the oil guided to the oil seal to the inside of the case are both provided between the metal bearing and the boss portion. ing. That is,
The oil supply passage and the oil discharge passage can be formed only by providing a groove or the like for communicating the space facing the oil seal with the gap on at least one of the outer circumference of the metal bearing and the inner circumference of the boss portion. Therefore, in the present invention, the oil supply passage and the oil discharge passage can be easily formed.

[Embodiment] Next, a lubrication mechanism of an oil seal of an ignition distributor according to the present invention will be described based on an embodiment shown in the drawings.

 FIG. 1 shows a cross-sectional view of an essential part of an embodiment of the present invention.

In the ignition distributor 100, the distributor drive shaft (hereinafter referred to as drive shaft) 110 is a camshaft 200 that is a rotating member of the present invention.
The rotation angle of the engine crankshaft, the ignition timing, etc. are detected from the rotation position of the drive shaft 110.

The connecting member 120 is provided at the end of the drive shaft 110 protruding from the boss 131 of the housing 130 that holds the end of the drive shaft 110. The connecting member 120 has a diameter larger than that of the drive shaft 110, and has an end surface on the side to which the cam shaft 200 is connected, which is provided with a protrusion 121 fitted into a groove 201 formed in the end surface of the cam shaft 200.

At the end of the boss 131 inside the housing 130, the drive shaft 11
A ball bearing 140 that rotatably supports 0 is provided, and a metal bearing 150 that rotatably supports the drive shaft 110 is also provided at an end portion outside the housing 130.
The boss portion 131 and the metal bearing 150 constitute the support portion A of the present invention.

Further, the inner periphery and the lip portion 161 are provided on the inner periphery of the boss portion 131 between the ball bearing 140 and the metal belling 150.
An oil seal 160 is provided that is in sliding contact with 110 and that prevents oil in the cam cover 210, which is the case of the present invention that wraps the cam shaft 200, from entering the housing 130.

As shown in FIG. 2, the end surface of the boss portion 131 on the connecting member 120 side is provided with a step 132 of about 1 to 2 mm that divides the end surface into two parts from the center. Due to the step 132, the supporting portion A
A wide gap portion 133 and a narrow gap portion 134 are formed between the end surface of the and the connecting member 120. In order to avoid interference, the length between the end surface of the boss 131 of the narrow gap portion 134 and the connecting member 120 in this embodiment is, for example, 0.5 to 1.5 mm.
It is set to the extent.

Two grooves 135 and 136 are formed on the inner circumference of the boss 131 on the coupling member 120 side of the oil seal 160. The two grooves 135 and 136 are surrounded by the metal bearing 150, one of which is the oil supply passage 170 of the present invention, and the other of which is the oil discharge passage 180.

The oil supply passage 170 includes a connecting member 120 and a housing 130.
Oil intake port 171 that opens to a wide gap 133 between
And boss 131, metal bearing 150, oil seal 16
An oil supply port 172 opened in a space 137 facing the oil seal 160 surrounded by 0 is provided. Also, the oil discharge passage 1
80 is provided with an oil discharge port 181 opening to a narrow gap 134 between the connecting member 120 and the housing 130, and an oil outlet port 182 opening into the space 137. An oil reservoir is formed in the space 137 at a portion lower than the oil supply port 172 or the oil discharge port 181.

The oil supply passage 170 is provided at the same position as or higher than the oil discharge passage 180, and in this embodiment,
As shown in FIG. 2, they are provided at the same height and face each other via the center of the drive shaft 110.

The cam cover 210 on the axial extension of the cam shaft 200 is provided with an insertion hole 211 for disposing the connecting member 120 provided on the drive shaft 110 of the ignition distributor 100 in the cam cover 210. When the boss portion 131 of the housing 130 is fitted into the insertion hole 211, the projection 121 of the connecting member 120 is fitted into the groove 201 of the cam shaft 200, and the rotation of the cam shaft 200 is transferred to the drive shaft 110 via the connecting member 120. Transmitted. The housing 130 is fastened to the cam cover 210 with the bolt 220. An O-ring 190 is provided in the groove 138 formed on the outer periphery of the boss portion 131, and with the boss portion 131 inserted in the insertion hole 211, the oil is inserted between the boss portion 131 and the insertion hole 211. Are prevented from leaking to the outside of the cam cover 210.

 Next, the operation of the above embodiment will be described.

When the engine starts and the camshaft 200 rotates,
The connecting member 120 connected by the groove 201 and the protrusion 121 rotates, and the drive shaft 110 connected thereto also rotates.

When the connecting member 120 rotates, a negative pressure is generated between the connecting member 120 and the end surface of the support portion A.

Since the gap between the connecting member 120 and the end face of the support portion A is different between the wide gap portion 133 and the narrow gap portion 134, a weak negative pressure is generated in the wide gap portion 133 and the narrow gap portion 134.
Then, a strong negative pressure is generated.

As a result, as shown in FIG.
And a pressure difference corresponding to the rotation speed of the camshaft 200 occur between the oil outlet 182 and the oil outlet 182. When the rotation speed of the camshaft 200 increases and the pressure difference increases, the oil supply passage 170
The air in the cam cover 210 is sucked and supplied into the space 137, and the air in the space 137 is again discharged into the cam cover 210 from the oil discharge passage 180.

With the flow of air due to the pressure difference between the wide gap portion 133 and the narrow gap portion 134, the oil scattered in the cam cover 210 and the oil flowing along the inner wall of the cam cover 210 are sucked into the oil suction port 171. It is supplied to the space 137 facing the oil seal 160 and stored in the oil reservoir. Then, the oil supplied to the space 137 is the oil seal 160
Is lubricated, and the oil is again discharged from the oil discharge passage 180 into the cam cover 210.

According to the present invention, since the oil is always positively supplied to the oil seal 160 when the camshaft 200 rotates, an oil film is always formed on the sliding surface between the lip portion 161 of the oil seal 160 and the drive shaft 110. The wear of the lip portion 161 of the oil seal 160 is prevented, and the oil in the cam cover 210 can be prevented from flowing into the housing 130 of the spark distributor 100.

(Modification) In the above embodiment, the wide gap portion and the narrow gap portion are provided so as to change abruptly due to the step, but the boundary between the wide gap portion and the narrow gap portion may be gently continuous. good.

The shapes and proportions of the wide-gap portion and the narrow-gap portion are not limited to those in this embodiment, and if a pressure difference occurs between the wide-gap portion and the narrow-gap portion when the connecting member rotates, Any shape and ratio may be used.

Although the example in which the position of the oil supply passage is provided at substantially the same height as the oil discharge passage or at a position higher than the oil discharge passage is shown, the position of the oil supply passage may be provided at a position lower than the oil discharge passage.

Although an example using a camshaft as a rotating member of an internal combustion engine is shown, it is applied to all members that rotate according to the rotation of the crankshaft during operation of the internal combustion engine, such as the crankshaft, sprocket shaft, and support shaft of the oil pump gear. can do.

The support portion was composed of the boss portion of the housing and the metal bearing, and the oil supply passage and the oil discharge passage were formed on the inner surface of the boss portion.However, the oil supply passage and the oil discharge passage may be provided on the inner or outer circumference of the metal bearing. The metal bearing may be omitted and the support portion may be formed of a boss portion, and the boss portion may be provided with an oil supply passage and an oil discharge passage.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing an essential part of an embodiment of the present invention, FIG. 2 is a sectional view taken along the line I-I of FIG. 1, and FIG. FIG. 4 is a graph showing the relationship between the pressure difference generated between the oil outlet and the oil outlet and the rotational speed of the camshaft, and FIG. 4 is a cross-sectional view showing a conventional oil seal lubrication mechanism. In the figure, 110 …… Distributor drive shaft, 120 …… Coupling member, 130 …… Housing, 133 …… Wide gap, 13
4 …… Narrow part, 160 …… Oil seal, 170 ……
Oil supply passage, 171 …… Oil inlet, 172 …… Oil supply inlet, 180 …… Oil discharge passage, 181 …… Oil outlet, 182 …… Oil outlet, 200 …… Camshaft, 210
…… Cam cover, A …… Supporting part

Claims (1)

(57) [Claims] 1. A metal bearing having a connecting member for connecting to a rotating member in a case of an internal combustion engine in which oil is scattered, a distributor drive shaft having a diameter smaller than that of the connecting member, and the connecting member side of the distributor drive shaft being a metal bearing. A boss portion of the housing supported via, and between the distributor drive shaft and the boss portion,
And an oil seal disposed on a side different from the connecting member with respect to the metal bearing, an oil suction port opened between the boss portion and the connecting member, and a space facing the oil seal. An oil supply port that is opened between the metal bearing and the boss portion, an oil outlet opening between the boss portion and the connecting member, and the space. Has an oil outlet that opens,
An oil discharge passage provided between the metal bearing and the boss portion, wherein a surface of the boss portion on the connecting member side is provided such that a gap between the boss portion and the connecting member is partially different. The intake port is opened in a portion where the gap between the boss portion and the connecting member is wide, and the oil outlet is opened in a portion where the gap between the boss portion and the connecting member is narrow. Lubrication mechanism for electric oil seals.