Automatic control device for a motorized vehicle gearbox

An automatic control device is provided for a gearbox of a motorized vehicle. The motorized vehicle gearbox includes a movable block movable between a forward driving position, a neutral position, and a reverse driving position. The automatic control device includes a motor, a transmission gear driven by the motor and including an eccentric axle provided thereon, a connecting rod having an end rotatably connected to the eccentric axle, an eccentric block including an end rotatably connected to the other end of the connecting rod, and an actuating device including a first end securely connected to the other end of the eccentric block and a second end securely engaged with the movable block to move therewith. When the motor is activated, the transmission gear is driven to move the movable block to one of the forward driving position, the neutral position, and the rearward driving position.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an automatic control device for a motorized vehicle gearbox.

2. Description of the Related Art

A typical two-wheeled motorized vehicle cannot move backwards. Nevertheless, a beach motorcycle must have this function to avoid getting stuck when desired.

FIG. 15of the drawings illustrates a conventional motorized vehicle gearbox with a control mechanism for controlling forward/backward movement.FIG. 16is a perspective view of main parts of the gearbox inFIG. 15. The gearbox includes a transmission shaft4′, a first gear1′ mounted on the transmission shaft4′ via a bearing11′ for forward driving, a second gear2′ mounted on the transmission shaft4′ via a bearing21′ for rearward driving, a first follower shaft6′, and a second follower shaft7′. A movable block3′ is mounted on the transmission shaft4′ to move therewith. Further, the movable block3′ is slidable along a longitudinal direction of the transmission shaft4′. The movable block3′ includes two protrusions31′ respectively on two sides thereof for respectively and releasably engaging with one of an engaging groove12′ defined in a side of the first gear1′ and an engaging groove22′ defined in a side of the second gear2′. The movable block3′ is connected to an actuating rod5′ to move therewith.

When the actuating rod5′ is shifted to move the movable block3′ to a position in which one of the protrusions31′ is engaged in the engaging groove12′ of the first gear1′ or the engaging groove22′ of the second gear2′, one of  the first shaft6′ and the second shaft7′ is turned, thereby driving the motorized vehicle forward or backward. However, operation of the actuating rod5′ is required.

FIG. 17of the drawings illustrates a motorized vehicle gearbox with another conventional control mechanism for controlling forward/backward movement.FIG. 18is a perspective view of main parts of the gearbox inFIG. 17. To solve the inconvenience of operation of the actuating rod, the control mechanism inFIG. 17comprises an automatic control device8′ including a motor81′, a reduction gear82′, and a screw83′ that meshes with the actuating rod50′. Thus, the motor81′ can be activated to move the actuating rod50′ via transmission by the reduction gear82′ and the screw83′. Nevertheless, the motor81′ must be activated to turn in a reverse direction for moving the actuating rod50′ in a reverse direction, which causes inconvenient control movement. Further, the travel “X” (FIG. 17) of the first gear1′ to the second gear2′ (or vice versa) is fixed, yet the travel of the actuating rod50′ on the screw83′ is not fixed. As a result, the movable block3′ might impinge the first gear1′ and/or the second gear2′.

Further, the protrusion31′ of the movable block3′ may not be exactly aligned with, e.g., the engaging groove12′ of the first gear1′ (FIG. 18) during rotation of the movable block3′. Namely, the movable block3′ has to turn through a small angle to allow insertion of the protrusion31′ into the engaging groove12′. Transmission of the control device is not reliable. Further, damage to the parts of the control mechanism resulting from impingement occurs, as no buffering means is provided.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an automatic control device for a gearbox of a motorized vehicle. The motorized vehicle gearbox includes a movable block movable between a forward driving position for driving the motorized vehicle forward, a neutral position, and a reverse driving position for driving the motorized vehicle rearward.

The automatic control device includes a motor, a transmission gear driven by the motor and including an eccentric axle provided thereon, a connecting rod having a first end rotatably connected to the eccentric axle and a second end, an eccentric block including a first end rotatably connected to the second end of the connecting rod and a second end, and an actuating device including a first end securely connected to the second end of the eccentric block and a second end securely engaged with the movable block to move therewith.

When the motor is activated, the transmission gear is driven to move the movable block via transmission by the eccentric axle, the connecting rod, the eccentric block, and the actuating device, thereby moving the movable block to one of the forward driving position, the neutral position, and the rearward driving position.

In an embodiment of the invention, the actuating device includes an actuating wheel having a longitudinal axle extending therefrom. The longitudinal axle of the actuating wheel is securely connected to the second end of the eccentric block. A positioning groove is defined in a periphery of the actuating wheel and includes three positioning sections respectively corresponding to the forward driving position, the neutral position, and the rearward driving position of the movable block. An actuating rod includes a first end slidably guided in the positioning groove and movable between the three positioning sections. The  actuating rod further includes a second end connected to the movable block to move therewith. The motor turns in the same direction to drive the actuating wheel in a first direction and then in a second direction opposite to the first direction.

In another embodiment of the invention, the actuating device includes a rod having a first end and a second end. An axle is formed on the first end of the rod and securely connected to the second end of the eccentric block. The second end of the rod is connected to the movable block to move therewith. The motor turns in the same direction to drive the rod in a first direction and then in a second direction opposite to the first direction.

An elastic element is provided for absorbing additional travel of the motor in a case that the movable block is in one of the forward driving position and the rearward driving position and that a protrusion of the movable block4is not aligned with an engaging groove of an associated one of a first gear and a second gear of the gearbox.

A sensor may be mounted on the eccentric block and a sensing device may be provided for detecting an angular position of the eccentric block by means of detecting a position of the sensor. The sensing device stops the motor based on detected angular position of the eccentric block, thereby positioning the movable block in one of the forward driving position, the neutral position, and the rearward driving position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring toFIGS. 1 through 3, an automatic control device in accordance with the present invention is designated by10and designed for use with a motorized vehicle gearbox. The gearbox includes a transmission shaft1, a first gear2mounted on the transmission shaft1via a bearing (not labeled) for forward driving, a second gear3mounted on the transmission shaft1via a bearing (not labeled) for rearward driving. A movable block4is mounted on the transmission shaft1to move therewith. Further, the movable block4is slidable along a longitudinal direction of the transmission shaft1. The movable block4includes two protrusions41respectively on two sides thereof for respectively and releasably engaging with one of an engaging groove21defined in a side of the first gear2and an engaging groove31defined in a side of the second gear3, thereby driving the motorized vehicle forward or backward.

The automatic control device10comprises a motor11, a reduction gear12, a transmission gear13, a connecting rod14, an eccentric block15, an actuating device16, an elastic element17, and a sensing device18. The motor11includes an output shaft110for driving the reduction gear12that meshes with the transmission gear13. An eccentric axle131is provided on the transmission gear13and rotatably connected to an end of the connecting rod14. Further, a linking rod141has a first end rotatably mounted to the axle131and a second end that has a longitudinal axis coincident with a rotating axis of the transmission gear13. The linking rod141is provided for improving rotational stability.

A peg151is formed on an end of the eccentric block15and rotatably connected to the other end of the connecting rod14. A sensor1511is mounted on the peg151. Also formed on the end of the eccentric block15is an actuating peg152that is located corresponding to the elastic element17. Formed on the other end of the eccentric block15is a hole153, which will be described later.

The actuating device16includes a substantially cylindrical actuating wheel160having a longitudinal axle161extending therethrough. The longitudinal axle161is securely received in the hole153of the eccentric block15. An abutting member162is formed on an end face of the actuating wheel160. Further, a positioning groove163is defined in a periphery of the actuating wheel160. An actuating rod164includes a first end slidably guided in the positioning groove163and a second end connected to the movable block4to move therewith. The positioning groove163includes three positioning sections “A”, “B”, and “C” corresponding to a forward gear position, a neutral gear position, and a reverse gear position, respectively.

The elastic element17is mounted around the axle161of the actuating device16and includes a first end abutting against the actuating peg152and a second end abutting against the abutting member162.

The sensing device18controls operation of the motor11and is mounted adjacent to the eccentric block15. Further, the sensing device18faces the forward gear position, neutral position, and reverse gear position and cooperates with the sensor1511on the eccentric block15.

The motor11can be activated to drive the reduction gear12and the transmission gear13for moving the connecting rod4and the eccentric block5. The actuating peg152of the eccentric block5presses against the first end171of the elastic element17, and the second end172of the elastic element17presses against the abutting member162of the actuating wheel160of the actuating device16, thereby driving the actuating wheel160to turn. Further, the actuating rod164slides along the positioning groove163for shifting the movable block4to a first position engaging with the first gear2for forward driving, a second position (neutral position), or a third position engaging with the second gear3for backward driving.

When the transmission gear13turns and moves the connecting rod14counterclockwise to a position shown inFIGS. 4 and 5, the actuating rod164is located in the positioning section “A” as a result of counterclockwise rotation of the actuating wheel160. Meanwhile, the protrusion41of the movable block4is engaged with the engaging groove21of the first gear2for driving the motorized vehicle forward.

When the transmission gear13further turns and moves the connecting rod14counterclockwise to a position shown inFIGS. 6 and 7, the actuating rod164is located in the positioning section “B” as a result of further counterclockwise rotation of the actuating wheel160. Meanwhile, the movable block4is in a neutral position not engaging with any one of the first gear2and the second gear3.

When the transmission gear13further turns and moves the connecting rod14counterclockwise to a position shown inFIGS. 8 and 9, the actuating rod164is located in the positioning section “C” as a result of further counterclockwise rotation of the actuating wheel160. Meanwhile, the other  protrusion41of the movable block4is engaged with the engaging groove31of the second gear3for driving the motorized vehicle backward.

When the transmission gear13further turns and moves the connecting rod14counterclockwise to a position shown inFIGS. 10 and 11, the actuating rod164returns to the positioning section “B” as a result of clockwise rotation of the actuating wheel160. Meanwhile, the movable block4is in a neutral position not engaging with any one of the first gear2and the second gear3. Thus, the motor11and the transmission gear13always turn in the same direction for driving the actuating wheel160in the clockwise direction or the counterclockwise direction. The operational stability is improved, as reverse rotation of the motor11is not required. Further, travel of the movable block4can be precisely determined by the connecting rod14and the positioning groove163.

The sensing device18may detect position of the sensor1511and deactivates the motor11, thereby stopping the actuating rod164in the desired position (forward gear position, neutral position, or reverse gear position). In particular, the sensing device18detects an angular position of the eccentric block15by means of detecting a position of the sensor1511on the eccentric block15. The sensing device18stops the motor11based on detected angular position of the eccentric block15, thereby positioning the movable block4in one of the forward driving position, the neutral position, and the rearward driving position.

Referring toFIG. 12, in a case that the movable block4is in one of the forward driving position and the rearward driving position and that the respective protrusion41of the movable block4is not aligned with the engaging groove21of the first gear2(or the engaging groove31of the second gear3), the motor11still turns11so as to move the transmission gear13and the eccentric block13to a predetermined position, the actuating peg152of the eccentric block15turns  and thus causes displacement of the first end171of the elastic element17. Meanwhile, the movable block4turns to urge the respective protrusion41of the movable block4to be aligned with the engaging groove21of the first gear2(or the engaging groove31of the second gear3). The second end172of the elastic element17turns the abutting member162and the actuating wheel16to a predetermined position under the action of the elasticity of the elastic element17. Thus, the elastic element17absorbs the additional travel of the motor11, the transmission gear13, and the eccentric block15and thus improves operational stability.

FIGS. 13 and 14illustrate another embodiment of the invention, wherein the actuating device16is replaced by another actuating device including a rod19having a first end and a second end. An axle191(which corresponds to the axle161of the first embodiment) and an abutting member192(which corresponds to the abutting member162of the first embodiment) are formed on the first end of the rod19. Further, an engaging member193is formed on the second end of the rod19for securely engaging with the movable block4. The movable block4is moved in a manner substantially the same as that in the first embodiment when the motor11turns.

According to the above description, the automatic control device in accordance with the present invention includes the following advantages:

1. The transmission gear1and the motor11always turn in the same direction to move the movable block4. Namely, reverse rotation of the motor11is not needed, providing smooth operation.

2. The movable block4can be reliably retained in one of the forward gear position, neutral position, and reverse gear position.

3. The sensing device18and the sensor1511precisely stop the motor11, thereby precisely positioning the movable block4.

4. The elastic element17absorbs additional travel of the motor11, the transmission gear13, and the eccentric block15resulting in misalignment between the respective protrusion41of the movable block4and the respective engaging groove21,31. The operational stability is thus improved.

Although the invention has been explained in relation to its preferred embodiments, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the invention as hereinafter claimed.