JPS628683Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a reverse transmission device used in a tricycle or the like.

Unlike conventional tricycles, tricycles equipped with balloon tires have a simple structure similar to motorcycles, and the transmission uses a forward-only gear shift cam system similar to motorcycles. However, in the case of a tricycle, it is desirable to be able to move backwards in terms of mobility.

Therefore, it has been considered to attach a reverse transmission to the above-mentioned gear shift cam type general driving transmission. A method was devised in which the back gear was shifted via a fork and engaged with the idle gear. However, in this method,
In order to prevent the back gear from being shifted by mistake, the gear shift drum must be rotated to shift the back gear only after the stopper is engaged with the gear shift drum and the stopper is released using the back gear release lever. It is necessary to make sure that this is not possible. Therefore, it is necessary to operate both the release lever and the gear shift drum operation lever, which is troublesome. Also, if you release the stopper using the release lever,
Even when the transmission gear output shaft rotates at high speeds, such as when going down a hill or coasting, the back gear can be forcibly shifted using the gear shift drum operating lever, reducing the noise caused by gear meshing. There is a disadvantage that a dangerous situation may occur in which a problem occurs or a sudden backlash occurs.

In view of the above-mentioned circumstances, the object of the present invention is to provide a reverse transmission device for use in conjunction with a gear shift drum-type general driving transmission device of a tricycle such as the one described above, which can shift the reverse gear with a single and simple operation. The object of the present invention is to provide a reverse transmission that can shift the gear and prevent the back gear from shifting when the output shaft of the transmission rotates at high speed. A back gear shift fork is attached to the shaft so as to move together with the shaft, the shaft is always biased in one direction by an elastic member, and a stopper cam is provided at the tip of the shaft in the biasing direction to restrict movement of the shaft. The reverse transmission is characterized in that the stopper cam and the elastic member shift the back gear via the shaft and fork.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.

FIG. 1 is a conceptual sectional view showing an embodiment of the reverse transmission according to the present invention, which is attached to a gear shift drum type transmission for general driving.

In the figure, 1 is an intermediate shaft of a general driving transmission to which rotation is transmitted from the engine crankshaft via a clutch (not shown), 2 is an output shaft installed parallel to the intermediate shaft 1, 1 and the output shaft 2 is provided with a multi-speed gear 3 (only a portion of which is shown) for general driving. The rotation of the intermediate shaft 1 transmitted from the crankshaft is changed in speed via the speed change gear 3 and transmitted to the output shaft 2, and then to wheels (not shown).

The reverse transmission according to the present invention includes a reverse drive gear 4 provided on the intermediate shaft 1, and a reverse idle gear 5 (not shown in FIG. 1, see FIG. 2) that is always engaged with the gear 4. A back driven gear 6 is spline-engaged with the output shaft 2 and positioned adjacent to the gear 5 so as to be disengaged from the gear 5.
Back gear shift fork 7 to move in the direction
, a shift fork shaft 8 on which the fork 7 is attached, and an elastic member (in this embodiment, a coil spring) 9
, a stopper cam 10 provided at the tip of the shaft 8 in the urging direction, and a backing lever 11 for rotating the cam 10.

The driven gear 7 is attached to the shaft 8 by press fitting or by a circlip 12 or the like in order to move together with the shaft 8. The shaft 8 is also provided with a shift fork (not shown) for shifting the speed change gear 3 for general driving. The cam 10 has a front plate 10a and a rear plate 10b arranged at a predetermined interval in the axial direction of the shaft 8, and both plates 10.
a and 10b (see FIG. 3, which is a view in the direction of arrow D in FIG. 1), and the pivot shaft 1 of the back lever 11 is connected to the back lever 11 via an arm plate 13.
It is fixedly installed in 1a. This stopper cam 10 is moved to the lower position shown by the solid line in FIGS. 1 and 3 by depressing the rear pedal 11c of the back lever, and to the third position by depressing the front pedal 11b.
This is the upper position indicated by the chain double-dashed line in the figure. As described above, the shaft 8 is urged in the direction of the cam 10 by the spring 9, so when the cam 10 is in the downward position, the tip of the shaft 8 contacts the front plate 10a, and when the cam 10 is in the upward position, it contacts the rear plate 10b. . In order to position the cam 10 at these two positions, two recesses are provided in the arm plate 13, and a positioning stopper 14 for engaging the ball is provided in the recesses.

Further, the back gear shift fork 7 is provided with a protrusion 7a, and this protrusion 7a is fitted into a back gear shift fork regulation groove 15a provided on the gear shift drum 15 for general driving. The gear shift drum 15 is arranged parallel to the output shaft 2,
As shown in FIG. 4, which is a developed view of the gear shift drum 15, the regulation groove 15a has a straight portion 15b extending perpendicular to the axial direction of the drum 15, and a straight portion 15b extending in the axial direction of the drum 15 at the neutral position N. It consists of a protruding portion 15c. That is, drum 15
The back gear shift fork 7 is configured to be shiftable only when is in the neutral position.

Next, the operation of this device will be explained.

FIG. 1 shows a neutral state during normal driving. During general driving, keep the rear pedal 11c depressed. Therefore, the cam 10 is in the above-mentioned lower position, and the forkshaft 8 moves in the direction of arrow C against the spring 9, and is positioned by the front plate 10a of the cam. Therefore, the driven gear 6 and the idle gear 5 do not mesh with each other (see FIG. 2).

To shift the driven gear 6 from this state, the front pedal 11b is depressed. Then, cam 1
0 is the upper position, the shaft 8 is in the spring 9
The rear plate 10b of the cam moves in the direction of arrow B.
is positioned in contact with the Then, together with the shaft 8, the fork 7 and the driven gear 6 are connected to the arrow B
The driven gear 6 shifts to mesh with the idle gear 5. In this case, the driven gear 6 is shifted by the spring 9 and cannot be forcibly shifted by the lever 11. In other words, since the driven gear 6 is moved by the spring 9, the driven gear 6 does not mesh with the idle gear 5 unless the rotational speed of the output shaft 2 becomes small, so there is no sudden backlash, and a safe and large gear mesh is achieved. No sound is generated.

Note that if the rear pedal 11c is depressed from this state, the shaft 8 is moved in the direction of arrow C by the cam 10, and both gears 5 and 6 are disengaged.

Further, the fork 7 is fitted into a regulating groove 15a of the drum via its protrusion 7a. In cases other than neutral during general driving, the above protrusion 7
a fits into the straight part 15b of the regulation groove, and arrows B and C
Directional movement is restricted to impossible. Therefore,
In this case, even if the front pedal 11b is depressed, the fork 7 does not move, and the driven gear 6 and idle gear 5
There is no risk of them interlocking. In addition, in the case of the neutral position, the protrusion 15c of the regulation groove is aligned with the shaft 8.
Since the driven gear 6 is formed in the axial direction of the front pedal 11b, the driven gear 6 is shifted via the fork 7 by depressing the front pedal 11b. Even if an attempt is made to rotate the gear shift drum, the drum cannot be rotated because the protrusion 7a of the fork is within the protrusion 15c parallel to the axial direction of the drum.

As mentioned above, the reverse transmission according to the present invention is a reverse gear (in the above embodiment, a reverse driven gear).
is shifted by an elastic member by operating a reverse lever, rather than by a lead groove of a general driving gear shift cam. Therefore, it is possible to shift the reverse gear by simply operating a single reverse lever, and since the gear is shifted by an elastic member, it is safe because it will not be shifted when the output shaft is rotating at high speed. There is no loud gear meshing noise.

Furthermore, by fitting the forks into the regulation grooves provided on the gear shift drum, double meshing of the gears can be completely prevented, resulting in safety.
Note that it is also possible to employ other means for preventing gear double meshing than this regulating groove.

It should be noted that the present invention can be modified in various ways without departing from its gist, and can be attached to devices other than the general driving transmission shown in the embodiment, and can also be applied to devices other than motor tricycles.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional conceptual diagram showing an embodiment of the reverse transmission device according to the present invention, Fig. 2 is a cross-sectional conceptual diagram showing the reverse drive gear, idle gear, and driven gear of the device shown in Fig. 1; 1 is a conceptual diagram viewed from the direction of arrow D in FIG. 1, and FIG. 4 is an exploded conceptual diagram of the gear shift drum shown in FIG. 1. 4... Back drive gear, 5... Back idle gear, 6... Back driven gear, 7
...back gear shift fork, 7a...protrusion,
8... Back gear shift fork shaft, 9...
...Elastic member, 10... Stopper cam, 11...
Back lever, 15...Gear shift cam, 15
a... Back gear shift fork regulation groove.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A back gear shift fork shaft is disposed so as to be movable in the axial direction, a back gear shift fork is attached to the shaft so as to move together with the shaft, and the shaft is constantly held in place by an elastic member. A stopper cam is disposed at the tip of the shaft in the biasing direction and restricts movement of the shaft, and the stopper cam and the elastic member are configured to shift the back gear via the shaft and fork. A reverse transmission device characterized by: (2) A protrusion is provided on the back gear shift fork, and the protrusion is fitted into a back gear shift fork regulation groove formed on the gear shift cam for general driving, so that the fork can be shifted only when the regulation groove is in the neutral position of the cam. The reverse transmission device according to claim 1 of the utility model registration claim, characterized in that the reverse transmission device has a shape.