JP2555661B2 - Joint structure - Google Patents

Description

TECHNICAL FIELD The present invention relates to a joint structure between a drive shaft and a driven shaft, and is particularly suitable for connecting a cam shaft or crank shaft of an internal combustion engine and a rotary shaft of a rotation angle sensor. Involved in various joint structures.

[Prior Art] Conventionally, expensive oil has been used as a lubrication method for a connecting portion that connects an output shaft of an internal combustion engine and a rotating shaft of an ignition distributor via a coupling.

Therefore, the present applicant has examined a structure in which oil lubrication is changed to relatively inexpensive grease lubrication and a structure employing grease lubrication (Japanese Patent Laid-Open No. 62-60980, etc.). There was a point.

[Problems to be Solved by the Invention] That is, in any case, grease is filled between the output shaft and the rotary shaft, but the grease is attached to the pin for rotatably connecting the coupling to the rotary shaft. , The lubrication of the pin is poor and the pin wears.
There is a problem that the durability of the pin is reduced. Therefore, in the structure in which the connecting portion is lubricated with grease, it is necessary to fix the coupling to the rotating shaft.

However, since there is a limit to manufacturing with high accuracy, mounting eccentricity generally occurs between the shaft center of the output shaft and the shaft center of the rotary shaft. Therefore, when mounting eccentricity occurs between the output shaft and the rotary shaft, if the coupling is fixed to the rotary shaft as described above, the mounting eccentricity between the output shaft and the rotary shaft can be corrected. Since it is not possible, the output shaft and the rotary shaft may not work together. For example, even if the output shaft and the rotary shaft work together, they are mounted in an eccentric state, so overload is applied to the rotary shaft bearing and rotary shaft, wear occurs at the joint, and durability of the joint decreases. I was afraid.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a joint structure that prevents mounting eccentricity between a drive shaft and a driven shaft and that allows a pin connecting a coupling and a driven shaft to be lubricated with grease.

[Means for Solving the Problems] A joint structure according to the present invention includes a drive shaft having an axial hole in which an engaging groove is formed, and a drive shaft fitted in the axial hole and having the engaging groove in one side. An engaging claw that engages with is projected, and the other is a coupling that is a tubular portion with a radial pin hole,
A driven shaft having a radial pin hole formed at an end portion fitted into the tubular portion of the coupling, and a driven shaft loosely fitted in the pin hole of the coupling and press-fitted into the pin hole of the driven shaft, In a joint provided with a pin for rotatably connecting a ring to a driven shaft, the axial hole is filled with grease for lubricating a sliding portion between the pin hole of the coupling and the pin, and the inside of the axial hole is filled with grease. In the gap between the circumference and the outer circumference of the cylindrical portion of the coupling, a seal member for preventing the grease from leaking is provided at the other end of the pin hole.

[Operation] The joint structure of the present invention has the following operation due to the above configuration.

The pin for connecting the coupling and the driven shaft is loosely fitted in the pin hole of the coupling and press-fitted into the pin hole of the driven shaft. It is fitted.

The coupling and the driven shaft are fitted into the axial hole of the drive shaft, which is prefilled with grease, with the engaging claws of the coupling at the head. At this time, when the coupling reaches the engagement groove formed in the bottom wall of the axial hole of the drive shaft while rotatably moving about the pin as a fulcrum, the engagement claws follow the inner wall of the engagement groove. However, by engaging at a predetermined position, the drive shaft and the driven shaft are connected with the mounting eccentricity corrected.

In the gap between the inner circumference of the axial hole of the drive shaft and the outer circumference of the cylindrical portion of the coupling, the seal member is provided on the other end of the pin hole, so the grease filled in the axial hole of the drive shaft is Since it penetrates into the sliding portion between the inner periphery of the pin hole and the outer periphery of the pin, the pin can be lubricated.

[Effects of the Invention] The joint structure of the present invention has the following effects due to the above configuration and operation.

It is possible to prevent mounting eccentricity between the drive shaft and the driven shaft,
In addition, the pin connecting the coupling and the driven shaft can be lubricated by the grease filled between the coupling and the drive shaft.

[Example] An example of the joint structure of the present invention will be described with reference to the drawings.

FIG. 1 shows a joint structure C between an engine E and a cam position sensor S using an embodiment of the present invention.

The engine E is mounted on an automobile and transmits rotational power from a cam shaft 11 which is a drive shaft to the outside. A center hole 12 is formed in the cam shaft 11 at a portion slightly eccentric from the shaft center. A ball 13 is driven into the center hole 12, and the ball 13 and the right side portion 14 in the figure serve as a lubricating oil passage for engine oil. On the contrary, in the left side portion 15 of the center hole 12 shown in the figure, an axial hole 16 having an inner diameter larger than the inner diameter of the central hole 12, and a cam position sensor S on the inner circumference of the bottom wall 17 of the axial hole 16 are provided. A substantially rectangular engagement groove 18 with which the connecting portion 2 engages is formed.

The cam position sensor S includes a connecting portion 2 that is connected to the cam shaft 11 of the engine E and a detecting portion 6 that detects the cam position.

The coupling portion 2 includes a coupling 3 that engages with the engagement groove 18 of the cam 11, a rotary shaft 4 that is a driven shaft that is coupled to the cam shaft 11 via the coupling 3, and the coupling 3 that is a rotary shaft. Four
The pin 5 is attached so as to be rotatable in a direction orthogonal to the axis of the.

The coupling 3 is entirely fitted in the axial hole 16 of the cam shaft 11 and rotates integrally with the cam shaft 11.
As shown in FIG. 2, the coupling 3 includes an annular portion 31 which is loosely fitted in the axial hole 16 of the cam shaft 11, and the annular portion 31.
A cylindrical portion 32 is provided so as to extend from the outer peripheral edge of 31 toward the left side in the drawing so as to form the same outer diameter as the annular portion 31.

The annular portion 31 has an engaging claw that engages with the engaging groove 18 of the cam shaft 11.
33 is projected toward the right side in the figure. The engaging claw 33 is
It is provided at a position slightly eccentric from the axial center of the coupling 3 (one-dot chain line in FIG. 2). In addition, the tip 33 of the engaging claw 33
The a is formed in a rectangular shape, and a taper 33c is formed from the tip 33a toward the root 33b. The taper 33c makes the engagement claw 33 easily engage with the engagement groove 18 of the cam shaft 11.

Here, since the cam position sensor S is a device that outputs an ignition timing signal, the positional relationship of the signal of a certain ignition timing (the positional relationship between the peaks of the timing rotors 61 and 62 and the pickups 63 and 64) is predetermined. There is. Therefore, when the engaging claw 33 is formed on the shaft center of the coupling 3 and the coupling 3 is attached to the cam shaft 11 with a shift of 180 degrees, the ignition timing will be shifted, so that the same direction will always be maintained in one rotation. Since it is necessary to attach the coupling 3 to the cam shaft 11, the engagement groove 18 of the cam shaft 11 and the engagement claw 33 of the coupling 3 are slightly decentered from the shaft center.

An annular groove 35 for mounting an O-ring 34, which is a sealing member, is formed at the left end of the outer periphery of the cylindrical portion 32 in the figure.
Further, the cylindrical portion 32 has an engaging claw 33 and an O-ring on the annular portion 31.
It has a pin hole 36 which is formed between an annular groove 35 in which 34 is mounted and which is formed at a position in the radial direction with respect to the axial center.
Here, the O-ring 34 includes the inner circumference of the axial hole 16 and the cylindrical portion 32.
Since it is provided on the left side of the pin hole 36 in the drawing in the gap with the outer periphery of the, the sliding portion 37 between the pin hole 36 and the pin 5 and the sliding portion 38 between the cylindrical portion 32 and the rotary shaft 4 are lubricated. It prevents the grease 39 from leaking from the axial hole 16.

The rotary shaft 4 is a housing 41 of the cam position sensor S.
Is rotatably supported by a bearing 42. Rotating shaft 4
The left side portion 43 in the figure is inserted into the housing 41 of the cam position sensor S, and the right side portion (hereinafter referred to as the tip portion) 44 in the figure is fitted into the cylindrical portion 32 of the coupling 3. The outer periphery of the tip portion 44 of the rotary shaft 4 and the cylindrical portion 32 of the coupling 3
A gap A is formed between the inner circumference and the inner circumference. Further, a pin hole 45 formed at a position in the radial direction with respect to the shaft center is formed in the tip end portion 44.

The pin 5 is loosely fitted in the pin hole 36 of the coupling 3 and is press-fitted into the pin hole 45 of the tip portion 44 of the rotary shaft 4. Further, a minute gap B is formed between the outer periphery of the pin 5 and the inner periphery of the pin hole 36 of the coupling 3.

The detection part 6 of the cam position sensor S is provided on the housing 41.
The timing rotors 61 and 62 are press-fitted into the left side portion 43 of the rotary shaft 4 in the drawing. Further, these timing rotors 61 and 62 detect an ignition timing signal by pickups 63 and 64 provided with a minute gap, respectively, and send the signal to a computer (not shown).

The operation of the joint structure C of the cam shaft 11 and the rotary shaft 4 of this embodiment will be described with reference to the drawings.

Rotating shaft 4 and detecting portion 6 of the preliminary cam position sensor S
Assemble and. Then, the cam position sensor S
The tip portion 44 of the rotary shaft 4 projecting from the housing 41 is fitted into the cylindrical portion 32 of the coupling 3. Then, the pin hole 36 of the coupling 3 and the pin hole 45 of the rotary shaft 4 are aligned with each other, the pin 5 is driven through one of the pin holes 36, the center part of the pin 5 is press-fitted into the pin hole 45, and both ends are The pin 3 is loosely fitted in both pin holes 36, and the coupling 3 is attached to the tip end portion 44 of the rotary shaft 4.

Then, the coupling 3 is rotatably coupled to the rotary shaft 4 in the arrow direction I orthogonal to the axis of the rotary shaft 4 by the gap A formed between the coupling 3 and the tip portion 44 of the rotary shaft 4. It Further, the coupling 3 is rotatable in the arrow direction II orthogonal to the axis of the rotating shaft 4 by the minute gap B formed between the coupling 3 and the pin 5 (smaller movement than the rotation movement in the arrow direction I). ) Is connected to the rotary shaft 4.

Therefore, the coupling 3 can move in the arrow directions I and II about the pin 5 as a fulcrum. At this time, the O-ring 34 is attached to the annular groove 35 formed on the outer periphery of the cylindrical portion 32 of the coupling 3.

Then, the tip end 44 of the coupling 3 and the rotary shaft 4 is set in advance with the engaging claw 33 of the coupling 3 at the top, and the grease
It is fitted in the axial hole 16 of the cam shaft 11 filled with 39. At this time, the coupling 3 moves rotatably in the directions I and II of the arrow, while the bottom wall 17 of the axial hole 16 of the rotary shaft 4 is moved.
When reaching the entrance of the engaging groove 18 formed in the, the taper 33c of the engaging claw 33 comes into contact with the inner wall of the engaging groove 18, and the taper 33c fits into a predetermined position along the inner wall of the engaging groove 18. . In this way, the engaging claw 33 of the coupling 3 is inserted into the engaging groove 18 of the cam shaft 11.
By engaging with, the cam shaft 11 and the rotary shaft 4 are connected in a state where the mounting eccentricity is corrected.

Therefore, it is possible to prevent the cam shaft 11 and the rotary shaft 4 from being attached in an eccentric state, and thus the bearing 42 of the rotary shaft 4 can be prevented.
Also, the durability of the connecting portion 2 can be improved without overloading the rotating shaft 4.

Here, the O-ring 34 includes the inner periphery of the axial hole 16 and the cylindrical portion.
It is provided on the left side in the drawing from the pin hole 36 in the gap between the outer circumference of 32. That is, the cylindrical portion 32 of the coupling 3
Since the pin hole 36 in which the pin 5 is loosely fitted is provided between the engaging claw 33 and the O-ring 34, the grease 39 filled in the axial hole 16 of the cam shaft 11 has the axial hole. From between the inner periphery of 16 and the outer periphery of the coupling 3, it will penetrate into the sliding portion 37 between the inner periphery of the pin hole 36 formed in the cylindrical portion 32 of the coupling 3 and the outer periphery of the pin 5, The pin 5 can be lubricated. Therefore, the joint structure C of the present embodiment can prevent wear of the pin 5 and prevent deterioration of the durability of the pin 5.

Furthermore, the grease that lubricated the pin 5 has two pin holes.
It flows out from the opening inside 36, and the cylindrical part of coupling 3
The sliding portion 38 between the inner periphery of 32 and the outer periphery of the tip end portion 44 of the rotating shaft 4 penetrates into the sliding portion 38, so that the sliding portion 38 between the coupling 3 and the rotating shaft 4 can be lubricated. It is possible to prevent abrasion with the rotating shaft 4 and deterioration of durability.

Other Embodiments In the present embodiment, the joint structure of the present invention is adopted as the joint structure of the cam shaft of the engine and the rotary shaft of the cam position sensor. It may be adopted in a joint structure between the shaft and the rotary shaft of the cam position sensor.

Further, it may be adopted in a joint structure between an output shaft such as a cam shaft or a crank shaft of an engine and a rotary shaft of equipment such as an ignition distributor and a rotation angle sensor. Further, it goes without saying that the invention can be applied to the joint structure between the drive shaft and the driven shaft of various devices without departing from the scope of the present invention.

In this embodiment, the engaging claw of the coupling is provided at a position slightly eccentric from the shaft center and at a position orthogonal to the pin. However, the engaging claw of the coupling is located at the shaft center or the pins 0 to 90. It may be provided at a position forming an angle of degrees, or a plurality of engaging claws may be provided. When the shape or the number of engaging claws is changed, the engaging groove of the drive shaft also needs to be deformed in accordance with the shape of the engaging claws.

In this embodiment, the O-ring which is the seal member is mounted on the outer circumference of the coupling, but it may be mounted on the inner circumference of the axial hole of the drive shaft. Further, as the seal member, a seal member such as an oil seal may be used instead of the O-ring.

[Brief description of drawings]

FIG. 1 is a sectional view showing a joint structure of an engine camshaft and a cam position sensor rotary shaft adopting an embodiment of the joint structure of the present invention, and FIG. 2 is an embodiment of the joint structure of the present invention. It is a half cross-sectional view showing a adopted connecting portion. In the figure, C ... Joint structure, E ... Engine, S ... Cam position sensor, 3 ... Coupling, 4 ... Rotating shaft (driven shaft), 5 ... Pin, 11 ... Cam shaft (driving shaft) , 16 …… Axial hole, 18 …… Engagement groove, 32 …… Cylindrical part, 33 …… Engaging claw, 34 …… O-ring (seal member), 36, 45 …… Pin hole

Claims (1)

(57) [Claims] 1. A drive shaft having an axial hole in which an engaging groove is formed, and an engaging claw which is fitted in the axial hole and engages with the engaging groove on one side. , The other is a coupling having a tubular portion with a radial pin hole, a driven shaft having a radial pin hole formed at an end fitted into the tubular portion of the coupling, and a pin of the coupling. A joint provided with a pin that is loosely fitted in a hole and press-fitted into a pin hole of the driven shaft, and that rotatably connects the coupling to the driven shaft, wherein the pin hole of the coupling and the pin hole are formed in the axial hole. Grease is filled to lubricate the sliding parts with the pin, and the grease is prevented from leaking to the other end of the pin hole in the gap between the inner circumference of the axial hole and the outer circumference of the cylindrical portion of the coupling. It is characterized in that a seal member for Hand structure.