JPH0125800Y2 - - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a shift device for an outboard motor.

The outboard motor shift device is as shown in Figure 1.
It has a shift cam 1 that strokes in the vertical direction,
A forward cam portion F is attached to the side of this shift cam 1.
, neutral cam part N, and reverse cam part R
are formed in stages, and this shift cam 1
The end of the push rod 2 is pressed into contact with the force of the return spring 3, and the push rod 2 is connected via a push pin 4 and a dog pin 5 to a shifter dog 7 spline-fitted to the outer periphery of the propeller shaft 6. It is adapted to be moved in the left-right direction in accordance with the vertical movement of the shift cam 1. When the end of the push rod 2 is positioned on the forward cam portion F of the shift cam 1 and the shifter dog 7 moves to the left in the figure, the claw 7a of the shifter dog 7 engages with the claw 8a of the forward gear 8, causing the rotation of the drive shaft 9. is transmitted to the propeller shaft 6 as forward rotation, and when the end of the push rod 2 is positioned on the reverse cam portion R of the shift cam 1 and the shifter dog 7 moves to the right in the figure, the claw 7a is transferred to the claw 10a of the reverse gear 10. When engaged, the rotation is transmitted to the propeller shaft 6 as reverse rotation, and when the end of the push rod 2 is positioned on the neutral cam portion N of the shift cam 1 and the shift dog 7 is placed in the neutral position, rotation is transmitted in either direction. It is becoming more and more difficult to do so.

However, in the above-mentioned conventional shift device, when the reverse cam portion R of the shift cam 1 hits the push rod 2 during reverse, that is, when the shift cam 1 has fully descended, the forward cam portion F moves downward. As a result, the shape of the tip end of the gear case 11 inevitably becomes large, making it difficult to obtain a streamlined shape with low fluid resistance.

This invention was made with the aim of focusing on the problems of the above-mentioned conventional technology and improving them.
The position of the push rod during forward or reverse operation is determined by contacting a contact part fixed to the gear case side, and the forward or reverse cam part of the shift cam is eliminated to shorten the overall length of the shift cam. An object of the present invention is to provide a shift device for an outboard motor that can be downsized and streamline the gear case.

Embodiments of this invention will be described below with reference to FIGS. 2 to 5, using the same reference numerals for parts common to those in FIG. 1.

The embodiment shown in FIG. 2 shows a case where the shift cam 1 is provided with a reverse cam portion R and a neutral cam portion N, but is not provided with a forward cam portion F.

The lower end of the neutral cam portion N has an inclined surface 1a facing toward the push rod 2 side, and has a pointed end portion 1a.
b is formed.

On the other hand, a contact portion 12 is formed in the gear case 11 on the same axis as the push rod 2, and is located at a position where the end of the push rod 2 comes into contact during forward movement and the pawl 7a of the shifter dog 7 engages with the pawl 8a of the forward gear 8. When the shift cam 1 is lowered while the push rod 2 is in contact with this contact portion 12, the tip portion 1b cuts between the contact portion 12 and the push rod 2 and pushes the push rod 2 back with its inclined surface 1a. It's becoming like that.

In addition, if there is a concern that the abutting part 12 will be abraded due to the push rod 2 coming into contact with this abutting part 12, the abutting part 12 should be made of the same material or the same hardness as the push rod 2, as shown in FIG. A member 13 can be embedded so that the end of the push rod 2 rests against this member 13.

Therefore, during reverse and neutral, the push rod 2 is pushed against the return spring 3 by the reverse cam portion R and the neutral cam portion N of the shift cam 1, and the shifter dog 7 is moved to shift the reverse gear 1.
0 engages with the claw 10a, or separates to maintain a neutral position.

At the time of forward movement, the shift cam 1 disengages upward from the end of the push rod 2 as shown in the third figure.
The push rod 2 is a contact portion 12 of the gear case 11.
At this time, the pawl 7a of the shifter dog 7 meshes with the pawl 8a of the forward gear 8, and forward rotation is transmitted to the propeller shaft 6.

To return to neutral again, lower the shift cam 1 so that its lower tip 1b touches the contact portion 12.
and the end of the push rod 2 and push the push rod 2 back, and when the end of the push rod 2 is located at the neutral cam portion N of the shift cam 1, the shifter dog 7 is placed in a neutral state in which it does not mesh with any gear. . To further reverse, move shift cam 1 further down.
The reverse cam portion R pushes the push rod 2, and the claw 7a of the shifter dog 7 engages the reverse gear 10.
The driving force is transmitted to the propeller shaft 6 in the form of reverse rotation. At this time, the neutral cam part N is lowered below the push rod 2 as shown in FIG. Only less is needed.

Note that if the relationship of shifter dog 7 to forward gear 8 and reverse gear 10 is reversed,
The shift cam 1 may be provided with a forward cam portion and a neutral cam portion.

As described above, this invention forms one cam part that engages the shifter dog with the reverse or forward gear and a neutral cam part on the side surface of the shift cam, and also forms the lower end into a pointed part, and the inside of the gear case that supports the propeller shaft. In addition, the shift cam has a contact part that determines the position where the end of the push rod comes into contact with the forward or reverse gear and can engage the shifter dog with the forward gear or reverse gear, so the shift cam has only one cam part and a neutral cam part. Therefore, the length of the shift cam can be shortened, which reduces the size of not only the shift cam but also the gear case, reducing weight and cost. In particular, it is possible to form the gear case into a streamlined shape with low fluid resistance. This will greatly contribute to increasing ship speed and reducing fuel consumption.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing a conventional outboard motor, Fig. 2 is a cross-sectional view of essential parts showing an embodiment of a shift device according to this invention, Figs. 3 and 4 are explanatory diagrams of the same operating state, FIG. 5 is a sectional view of the same modification. 1...Shift cam, 1a...Slope, 1b...
Point, 2... Push rod, 4... Push pin, 5... Dog pin, 6... Propeller shaft, 7... Shifter dog, 8... Forward gear, 10... Reverse gear, 11... Gear case, 12... Contact Department.

Claims (1)

[Scope of utility model registration request] The side surface of the shift cam in which the push rod follows the stroke of the shift cam, slides the shifter dog on the propeller shaft, and selectively engages the forward gear and reverse gear to switch between forward and reverse transmission of driving force to the propeller shaft. A cam part for engaging the shifter dog with the reverse gear or forward gear and a cam part for neutral are formed, and the lower end is formed into a pointed part, and the end of the push rod is placed in the gear case supporting the propeller shaft during forward or reverse operation. What is claimed is: 1. A shift device for an outboard motor, comprising: a contact portion that determines a position where a shifter dog can engage with a forward gear or a reverse gear;