JPS632902Y2 - - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention [Industrial Field of Application] The present invention relates to an improvement of a shift fork that is fitted into a circumferential groove of a coupling sleeve of a gear transmission to perform gear shifting.

[Prior Art] As a conventional shift fork for a transmission, there are those shown in FIGS. 1 to 3 for gear transmissions of automobiles, for example. For example, when shifting a synchronous mesh transmission to 1st speed, when the shift lever is put into 1st speed, the coupling sleeve 3 moves in the direction of arrow C due to the movement of the shift fork 1 fixed to the shift rod 2 via the coupling mechanism. Borkling 5 to 1
It is pressed against the cone surface 7 of the speed gear 6, and when the synchronizing action as a transmission ends, it completely engages with the clutch gear 8 of the first speed gear 6, completing the speed change. When shifting in this manner, a large load is applied to the sliding surface 9 between the sliding claw portion 1a of the shift fork 1 and the circumferential groove of the coupling sleeve 3, so that splashes due to the direction of gear rotation D and oil gutter of the gear case 4 are generated. Lubricating oil is supplied to this sliding surface by dripping from 10 and immersion in oil level E.

[Problems to be solved by the invention] However, in the shift fork 1 of such a conventional transmission, when trying to supply lubricating oil to the sliding surface 9 between the shift fork 1 and the coupling sleeve 3 in the B section, Also, since a large load is applied to the sliding surface 9 between the sliding claw portion 1a of the shift fork 1 and the circumferential groove of the coupling sleeve 3, lubricating oil cannot be smoothly supplied to the entire sliding surface. Also, since the coupling sleeve 3 is rotating, some of the lubricating oil may be splashed off the sliding surface, especially when the gear shift lever is operated quickly with great force.
When high-speed gears are used, the amount of lubricating oil is insufficient, and abnormal wear and seizure of the sliding surfaces 9 are likely to occur.

As a countermeasure, the sliding claw part 1 of the shift fork 1
It has been proposed to use abrasion-resistant chrome plating or other surface treatment on the sliding surface 9 of a, or to use a sintered alloy, but these methods have the drawbacks of high cost and insufficient effects. Also, there are some that have grooves or recesses in the sliding surface 9, or through holes between the sliding surfaces 9,
The purpose of replenishing lubricating oil is to retain and even out the lubricating oil that has entered the sliding surface 9.
It was passive and inadequate. Furthermore, if the coupling sleeve 3 rotates at high speed, a considerable portion of the lubricating oil may be splashed to the outside before being supplied to the entire sliding surface 9.

Further, if foreign matter gets mixed into the lubricating oil, it is likely to be caught on the sliding surface 9, which may even cause abnormal wear. In particular, the coupling sleeve 3, which has grooves or recesses on the sliding surface 9 for collecting oil, has the disadvantage that it becomes shallower due to wear and the oil collecting effect is reduced.

Composition of the invention Therefore, the present invention forms a part that actively collects lubricating oil dripping or splashing, and sends the oil to the sliding surface of the shift fork, and also prevents foreign matter from being captured on the sliding surface 9. With the aim of providing a shift fork with a structure that prevents the oil collection effect from decreasing due to wear, we adopted the following configuration.

[Means for Solving the Problems] That is, the gist of the present invention is to provide a shift fork of a transmission equipped with a supporting bone portion having a sliding pawl portion that is fitted into a circumferential groove of a coupling sleeve. , A through hole is provided between the two sliding surfaces of the sliding claw portion relative to the coupling sleeve, and a through hole is provided to communicate the two sliding surfaces, and a through hole is provided within the distal end surface of the supporting bone portion or the distal end surface of the sliding claw portion. A shift fork for a transmission is characterized in that it has an opening therein and an oil supply hole that intersects and communicates with the through hole.

[Function] The oil supply hole has an opening in the distal end surface of the supporting bone portion or the distal end surface of the sliding claw portion. The oil supply hole further intersects and communicates with a through hole provided between two sliding surfaces of the sliding claw portion relative to the coupling sleeve. Therefore, lubricating oil can be introduced not only through the gap between the coupling sleeve and the sliding pawl but also through the opening. Moreover, especially when the rotational speed increases, more lubricating oil collides with the opening and is supplied to the oil supply hole.

Further, the oil supply hole communicates with the sliding surface with the coupling sleeve via the through hole. Therefore, the lubricating oil is reliably supplied to the sliding surface without being splashed to the outside on the way.

Furthermore, even if foreign matter enters the oil supply hole, it will accumulate on the inner wall surfaces of the intersecting through holes, making it difficult for it to reach the sliding surface.

Next, an example of the present invention will be described. The present invention is not limited to these, but includes various embodiments without departing from the gist thereof.

[Embodiments] Next, embodiments of the present invention will be described with reference to the drawings shown in Figs.

4 and 5 show a first embodiment of the present invention, in which the outer shape of the support bone portion 41b and sliding claw portion 41a of the shift fork 41 is the same as that of the shift fork 1 shown in FIG. An oil supply hole 46 is bored in the circumferential direction of the coupling sleeve 3 from near the center of the tip surface 43a of the sliding claw part 41a, and the oil supply hole 46 is inserted into the coupling sleeve 3 within the sliding claw part 41a. That is, the sliding claw portion 41 penetrates in the axial direction of
A through-hole 47 bored to communicate both sliding surfaces 9 of a.
The sliding surface 9 can be easily connected to the sliding surface 9 without increasing the weight of the shift fork 41.
It is possible to send oil to

In the shift fork 41 configured as described above, dripped oil and splashed oil adhere to the tip surface 43a of the sliding pawl portion 41a or the tip surface 43b of the support bone portion 41b due to the rotation of the gear in the D direction, and the dripping oil and splashed oil adhere to the tip surface 43a of the sliding pawl portion 41a or the tip surface 43b of the support bone portion 41b, and are deposited at the opening. 4
The oil enters the oil supply hole 46 through the oil supply hole 46 through the through hole 47 and is delivered to the vicinity of the center of the sliding surface 9 between the sliding claw portion 41a and the coupling sleeve 3.

That is, the amount of lubricating oil supplied from the narrow gap between the tip surface 43 of the sliding pawl 41a and the coupling sleeve 3 is limited, and the amount that enters through that gap is also splashed away by centrifugal force. This alone tends to result in insufficient supply of the sliding surface 9.

However, since the opening 46a of the oil supply hole 46 is provided separately from the above-mentioned gap, it is possible to absorb the amount that cannot enter through this gap or the amount that cannot reach the gap at all. Moreover, once the oil enters the oil supply hole 46 and the through hole 47, there is no fear of it being blown away by centrifugal force, and the oil is reliably supplied to the sliding surface 9. And, there tends to be a shortage of supply.
A lubricating effect on the rear part of the sliding surface 9 can be achieved.

Furthermore, even if foreign matter enters the oil supply hole 46, it will accumulate on the inner wall surface of the through hole 47 that intersects and communicates with it, making it difficult for it to be discharged to the sliding surface 9. In addition, the sliding claw portion 41
Even if a is worn out, the oil supply hole 46 and through hole 47
Since it is provided inside the sliding claw portion 41a, the oil collection effect will not be reduced.

Shift fork 51 of the second embodiment shown in FIG.
The oil supply hole 56 and the through hole 57 are arranged in the same manner as the oil supply hole 46 and the through hole 47 in the shift fork 41 of the first embodiment shown in FIG. Therefore, the sliding claw part 5
The diameter of the opening 56a on the tip face 53a side of 1a is made larger than the diameter of the portion 56b that supplies oil to the through hole 57, and has the same effect as the first embodiment, as well as the ability to supply oil to the sliding surface 9. The amount of oil increases further.

Shift fork 61 of the third embodiment shown in FIG.
In this case, more lubricating oil is collided with the tip of the supporting bone portion 61b and captured than in the shift fork 41 of the first embodiment shown in FIG. It is configured to prevent the oil from escaping into the oil supply hole 66 and the through hole 67. That is, the distal end surface 63b of the support bone portion 61b is provided with an opening 66a of the oil supply hole 66, and the distal end surface 63b is surrounded by walls 63c, 63d, and 63e in three directions.
As a result, an oil collecting tank 68 is formed, which has openings on the surface opposite to the tip surface 63b and the surface opposite to the wall 63d. The oil supply hole 66 is provided to be inclined in the direction of the sliding claw portion 61a, and is communicated with a through hole 67 that is bored through the coupling sleeve 3 in the axial direction at the sliding claw portion 61a. . Therefore, it has the same effect as the first embodiment, and the distal end surface 63a of the sliding claw part 61a and the supporting bone part 61b
The escape of the lubricating oil that collided with the tip surface 63b is reduced, the amount of lubricating oil flowing into the oil supply hole 66 and the through hole 67 is further increased, and the amount of oil sent to the sliding surface is increased. In addition, depending on the amount of oil required, the oil supply hole 66 or the through hole 6
What is necessary is to change the direction, diameter size, and number of 7.

Effects of the invention The shift fork of the invention has an opening in the distal end surface of the supporting bone part or the sliding claw part, and a through hole as described above in the sliding surface of the sliding claw part and the coupling sleeve. Because it has a communicating oil supply hole, the necessary amount of lubricating oil is ensured even under harsh conditions such as when the sliding surfaces of the coupling sleeve and shift fork come into contact with each other under high load and at high speeds during gear shifts. Furthermore, even if foreign matter enters the sliding surface, it is unlikely to reach the sliding surface and will not be damaged, eliminating problems such as seizure or abnormal wear on the sliding surface, which has the effect of greatly improving durability. Furthermore, even if the sliding surfaces wear out, the oil collection effect will not deteriorate.

Further, the present invention is an effective shift fork that can obtain the above-mentioned great effects by simply improving the conventional shift fork by providing an oil supply hole and a through hole.

[Brief explanation of the drawing]

Figure 1 is a front view of a conventional shift fork incorporated into a transmission, Figure 2 is a sectional view of the main part taken along line A-A in Figure 1, and Figure 3 is an enlarged view of section B in Figure 2. A perspective view, FIG. 4 is a front view showing the state of use of the first embodiment of the present invention, and FIGS. 5 to 7 show the second or third embodiment of the shift fork of the present invention, corresponding to FIG. 3. It is a perspective view shown in parts. 3...Cut spring sleeve, 9...Sliding surface,
21... Lubricating oil splash, 41, 51, 61... Shift fork, 41a, 51a, 61a... Sliding claw portion, 41b, 51b, 61b... Support bone portion, 43
a, 53a, 63a...Sliding claw tip end surface, 43
b, 53b, 63b... distal end surface of supporting bone part, 46,
56, 66... Oil supply hole, 47, 57, 67... Through hole, 46a, 56a, 66a... Opening.

Claims (1)

[Claims for Utility Model Registration] 1. In a shift fork of a transmission equipped with a support bone portion having a sliding pawl portion that is fitted into a circumferential groove of a coupling sleeve, two of the sliding pawl portions relative to the coupling sleeve are provided. A through hole is provided between the two sliding surfaces to communicate the two sliding surfaces, and an opening is provided within the distal end surface of the supporting bone portion or within the distal end surface of the sliding claw portion, and A shift fork for a transmission characterized by forming oil supply holes that intersect and communicate. 2. The transmission shift according to claim 1, wherein the oil supply hole is formed so that the diameter on the distal end side of the support bone portion is larger than the diameter on the inside side of the support bone portion or the inside side of the sliding claw portion. Folk.