JPH01145452A - Shift gear for marine driving unit - Google Patents

Abstract

PURPOSE:To enable a dog to be smoothly and surely returned to a neutral position by providing the second detent mechanism in addition to the first detent mechanism. CONSTITUTION:Assuming a case that a dog 30 meshes with a forward gear 56, when a shift sleeve 68 is controlled moving in the leftward direction in the drawing, immediately before a pawl 64 of the dog 30 meshes with a pawl 66 of the gear 56, the first ball 84 is dislocated from the first stopper groove 92 escaping from a neutral position, but the second ball 86 comes into contact with a wide slope 96 of the second stopper groove 94, tending to return into the stopper groove 94. Consequently, the shift sleeve 68 and the dog 30 receive a detent load in a direction of returning to the neutral position. And in a condition that the dog 30 completely meshes with the gear 56, dislocating the second ball 86 from the second stopper groove 94, no detent load acts in the neutral direction. Thus receiving the detent load only by controlling the dog 30 to be released from the meshed condition, the dog is surely returned to the neutral position.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a shift device for a marine drive unit, and particularly to a shift device provided with a detent mechanism for maintaining a neutral position in a clutch for single forward/forward switching. Regarding equipment.

[Prior Art] Generally, a so-called dog clutch is used in a shift device for a marine propulsion device such as an outboard motor or an outboard/outboard motor to switch between forward and backward travel.

Ideally, this dog clutch could perform two functions at the same time: to smoothly engage the dog moving in the axial direction of the propeller shaft with the pawl of the forward/reverse gear, and to ensure that the dog returns to the neutral position. It is said to be a target.

On the other hand, it has been common practice to provide a so-called detent mechanism on the propeller shaft or shift rod (
For example, see Japanese Unexamined Patent Publication No. 59-156494), but it is difficult to achieve both of the above two functions with such a numerical detent mechanism. This is because in order to smoothly engage the dog, it is necessary to release the state in which the dog is held by the titent mechanism before the dog begins to engage, while in order to ensure that the dog returns to the neutral position, the dog can move as wide as possible. This is because it is necessary to apply a load to return the dog to the neutral position within the range, and these are considered to be contradictory to each other.

Therefore, in recent years, priority has been given to smooth engagement of the dogs, and the dogs are often urged in the direction of engagement from the time the dogs leave the neutral position. (Refer to Japanese Patent Application Laid-Open No. 59-9315) [Problems to be Solved by the Invention] However, in such products, for example, in an inboard/outboard motor, there are many problems in the shift link mechanism from the shift lever to the dog. If there are links intervening, looseness is likely to occur in the interlocking between the links, which may make it difficult for the dog to return to the neutral position.

The present invention has been made in view of the problems of the prior art, and its purpose is to solve the problem when the shift link mechanism from the shift lever to the dog has many links and a certain amount of play may occur. Another object of the present invention is to provide a shift device for a drive unit for a ship, which allows the dog to reliably return to the neutral position simply by disengaging the dog from meshing with a gear.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides forward and reverse propellers which are rotated in opposite directions by an engine drive shaft and fitted onto a propeller shaft so as to be freely rotatable. A ship comprising a gear, a dog that is operated to move in the axial direction of a propeller shaft and selectively meshes with both gears to transmit the rotation to the propeller shaft, and a first detent mechanism that holds the dock in a neutral position. a second detent mechanism that urges the dog to a neutral position at least from a position where the dog is released from the first detent mechanism to a position where the dog meshes with the one gear; It has been established.

[Function] With this configuration, the dog is simply moved from the state in which it is engaged with one of the forward and backward gears to the direction in which it is released from the state by the function of the second detent mechanism, and the dog is moved by the biasing force of the second detent mechanism. It automatically returns to the neutral position and is reliably held at the neutral position by the first detent mechanism.

[Example] The present invention will be explained below based on embodiments shown in the drawings.

First, FIG. 1 shows the overall configuration of the outboard portion of an inboard/outboard motor. Gimbal bouncing 1 on transom board lO
2 is fixed, a gimbal ring 14 is supported to be rotatable in the left and right directions with respect to the gimbal housing 12, and a swivel bracket 16 is supported to be rotatable in the up and down directions with respect to the gimbal ring 14 via a pin 18. , which constitutes a transom unit. By connecting the drive unit 22 to the swivel bracket 16, the drive unit 22 is fixed to the transom board 10 so as to be rotatable in the left and right and up and down directions. Reference numeral 24 denotes a universal joint connected to an engine (not shown), and the driven shaft of this universal joint 24 transmits its rotational power to the intermediate transmission shaft 28 via a gear mechanism 26, thereby controlling the rotation of the intermediate transmission shaft 28. Power is dog 30
It is transmitted to the propeller shaft 34 through the forward/reverse switching mechanism 32 having a forward/reverse motion, and rotates the propeller 36 to obtain the propulsion force for the ship.

38 is provided as part of the transom unit 20,
This is a bellows that covers the universal joint 24.

Reference numeral 40 denotes a remote control cable connected to a shift operation lever (not shown), and an arm shift rod 42 provided at the end thereof projects from the transom unit 20 side to the drive unit 22 side. This linear motion of the arm shift rod 42 is converted into a rotational motion and transmitted to a shift camshaft 46 provided on the drive unit 22 side via an intermediate swing link mechanism 44, and the rotational motion of this shift camshaft 46 is This is converted into a linear reciprocating motion of the dog 30 of the forward/reverse switching mechanism 32 and transmitted.

Reference numeral 48 is a water pressure detection port for a water pressure detection device using a pitot tube, and is connected to the lower casing 50 of the drive unit 22.
It is open at the front end. 52 is a tilt switch for tilting the drive unit 22 in the vertical direction;
is an anode provided at a position covering an idle hole (not shown).

FIG. 2 shows the structure of the forward/reverse switching mechanism 32 in detail. This forward/reverse switching mechanism 32 includes a forward and reverse gear 56 fitted on the propeller shaft 34 so as to be freely rotatable.
58, these gears 56.5 mesh with a bevel gear 62 fixed to a drive shaft 60 driven by the engine and are rotated in opposite directions. The propeller shaft 34 has the dock 30 between the gears 56 and 58.
The propeller shaft 34 is spline-coupled and is slidable in the axial direction of the propeller shaft 34. The dog 30 is provided with a pair of pawls 64, 64 that protrude outward in the axial direction, and the gears 56, 58 are each provided with a pawl 66, 66 that opposes the pawls 64, 64. It is formed.

A substantially cylindrical shift sleeve 68 is inserted into the propeller shaft 34 along its axial direction so as to be movable forward and backward in the axial direction. Cross bin 70 fixed to this shift sleeve 68
The dog 30 passes through the propeller shaft 34 in a direction perpendicular to the axis of the propeller shaft 34 with sufficient play, and both ends thereof face the annular groove 72 of the dog 30 and are prevented from falling off by a coil spring 74. As a result, the movement of the shift sleeve flow 8 is transmitted to the dog 30.

A large-diameter head 76 is formed at the end of the shift sleeve 68 protruding from the propeller shaft 34, and a U-shaped cross-section locking portion 80 of the cam follower 78 is locked to the large-diameter head 76. When the shift camshaft 46 is rotated, the cam follower 78 is moved in the axial direction of the propeller shaft 34 through the sliding relationship between the cam portion 82 at the lower end of the shift camshaft 46 and the cam follower 78, whereby the shift sleeve is moved. 6
8 is moved in the axial direction.

The shift sleeve 68 is provided with two detent mechanisms. The first detent mechanism includes a plurality of first balls 84 that penetrate through the shift sleeve 6 in the radial direction and move forward and backward, and the second detent mechanism also includes a plurality of similar second balls 84 located at a position spaced apart from the first hole 84 in the axial direction. It is equipped with 86. The first hole 84 and the second ball 86 are held in a first holding hole 85 and a second holding hole 87 formed in the shift sleeve 68, respectively, and are held in a pair of extruded balls 88 arranged in the shift sleeve flow 8. These first
By contacting the lower portions of the ball 84 and the second ball 86 and urging the both pushing balls 88 in a direction away from each other by a spring 90 interposed between the pushing balls 88,
The first ball 84 and the second ball 86 in both cylinders are urged to protrude outward in the radial direction. On the other hand, a first locking groove 92 and a second locking groove 94 are formed in the inner peripheral wall surface of the propeller shaft 34 that accommodates the shift sleeve 68 so as to be able to move forward and backward, corresponding to the first ball 84 and the second ball 86, respectively. When the shift sleeve 68 and the dog 30 are in the neutral position, the first ball 84 and the second ball 86 are in the first position, respectively.
It is arranged so as to engage in the locking groove 92 and the second locking groove 94. Here, the first locking groove 92 needs to be locked only when the first ball 84 is in the neutral position, so its width is relatively narrow, and the force cylinder 2 locking groove 94 is comparatively narrow. Its width is wide, and its cross section is tapered and widens towards the end.

The operation of such a detent mechanism is
This will be explained based on the diagram. Here, the same or equivalent parts as in FIG. 2 are indicated by the same reference numerals, and the explanation of these parts will be omitted.

First, the state shown in FIG. 3A is in the neutral position,
The first ball 84 and the second ball 86 are accurately locked in the first locking groove 92 and the second locking groove 94, respectively. now dog 3
Assuming that the shift sleeve 68 is engaged with the forward gear 56, the shift sleeve 68 is moved to the left in the figure, resulting in the state shown in FIG. 3B.

The state shown in FIG. 3B is the claw 64 of the dock 30 or the claw 6 of the gear 56.
6, the first ball 84 has come off the first locking groove 92 and has left the neutral position. However, the second ball 86 is still in contact with the slope 96 of the wide second locking groove 94, and therefore the second ball 86 is still in contact with the slope 96 of the second wide locking groove 94.
By attempting to return to the inside, the shift sleeve flow 8 and the dock 30 receive a detent load in the direction of returning to the neutral position.

In the state shown in FIG. 3C, the dog 30 is fully engaged with the gear 56, and the second ball 86 is in the second locking groove 94.
, and the detent load in the neutral direction is no longer acting.

In this embodiment, the load by the second detent mechanism was applied from the neutral position of the dog 30 to just before the dog 30 meshed with one of the gears. The detent load may be applied to the neutral position even after the engagement with the shaft is completed.

In such a case, the dog stroke (moving pressure fllI
) and the detent load, that is, the load that attempts to return it to the neutral position, is shown in Figure 4. The detent load is at its maximum just before the dog starts to engage, and after that, even after #J starts, there is a slight It can be seen that a large detent load remains.

[Effects] As explained above, according to the present invention, since the second detent mechanism is provided in addition to the first detent mechanism, the dock can be brought to the neutral position extremely smoothly and reliably just by being released from the engaged state. It has a great effect of being able to go back.

[Brief explanation of the drawing]

Fig. 1 is a side view showing the entire inboard/outboard motor which is an embodiment of the shift device for a marine drive unit according to the present invention, Fig. 2 is a sectional view showing an enlarged main part of the same embodiment, and Fig. 3A 3C to 3C are schematic diagrams of the detent mechanism, in particular, FIG. 3A shows the state in the neutral position, FIG. 3B shows the state immediately before dog engagement, and FIG. 3C shows the state when dog engagement is completed. 22... Drive unit 30... Dog 32... Forward/backward switching mechanism 34... Propeller shaft 84... First ball 86... Second ball 92... First locking groove 94... ...Yoshiyuki Inaba, 2nd Suigamizo Attorney, Patent Attorney Proceedings Amendment (Hakudo February 1, 1986)

Claims (1)

[Claims] (1) Rotated in opposite directions by the engine drive shaft,
Forward and reverse gears are fitted on the propeller shaft so that they can rotate freely, and the dog of the dog clutch that is moved in the axial direction of the propeller shaft and selectively meshes with both gears to transmit the rotation to the propeller shaft. and a first detent mechanism for holding the dog in a neutral position, in which the dog is moved from at least the position where the dog is released from the first detent mechanism to the one gear. A shift device for a marine drive unit provided with a second detent mechanism that urges a dog to a neutral position until the dog is engaged.