CN106515841A - Control mechanism for variable transmission ratio steering system - Google Patents

Abstract

The invention discloses a control mechanism for a variable transmission ratio steering system. The control mechanism comprises a control switch, a control switch rack, a slidable rotating shaft, a variable length lever, a steering wheel rack, a planet gear frame, a gear ring, a sun gear, planet gears, a control cable, a motor and a passing gear. The sun gear and the steering wheel rack are engaged with each other. One end of the variable length lever is hinged to the steering wheel rack, and the other end of the variable length lever is connected with the control switch. The slidable rotating shaft can only slide up and down in a groove. The passing gear is engaged with an external gear of the gear ring and the control switch rack. The motor is engaged with the external gear of the gear ring. The planet gears are engaged with an internal gear of the gear ring and the sun gear. According to the control mechanism for the variable transmission ratio steering system, variable transmission ratio transmission of a steering mechanism of an automobile can be achieved, the transmission ratio of the steering mechanism is decreased during a low speed, the sensitivity is improved, the transmission ratio of the steering mechanism is increased during a high speed, the sensitivity is reduced, and the stability during driving is improved; and meanwhile, an angle sensor is not needed, so that the advantage of low cost is achieved.

Description

A Control Mechanism of Variable Transmission Ratio Steering System

technical field

The invention relates to an automobile steering system, in particular to a control mechanism of a variable transmission ratio steering system.

Background technique

The transmission ratio of the steering mechanism of an automobile is generally fixed, and the steering mechanism with a fixed transmission ratio has the advantages of simple structure and low cost. However, automobiles have different requirements for the transmission ratio of the steering mechanism at different speeds. When turning sharply or turning around at low speeds, the transmission ratio is expected to be smaller, which can increase the flexibility of the steering system and facilitate steering. And when driving at high speed, it is hoped that the transmission ratio of the turning mechanism is larger, so that the vehicle will not turn sharply because of a slight turn of the steering wheel, thereby increasing the stability of the vehicle. However, the steering mechanism with fixed transmission ratio cannot meet these two requirements at the same time.

In order to meet the requirements of flexibility and stability at the same time, some high-end cars use variable transmission ratio steering systems. These turning systems are realized through a set of two-degree-of-freedom planetary gear mechanisms or harmonic gear mechanisms, which require the installation of a drive The cost of the motor and angle sensor is relatively high.

Contents of the invention

Aiming at the above-mentioned problems existing in the steering mechanism of automobiles in the prior art, the present invention provides a control mechanism of a variable transmission ratio steering system to overcome the problem that the existing variable transmission ratio steering system needs to install an angle sensor, thereby bringing about high costs .

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

A control mechanism of a variable transmission ratio steering system, including a control switch, a control switch rack, a slidable rotating shaft, a variable length lever, a steering wheel rack, a planetary gear carrier, a ring gear, a sun gear, a planetary gear, a control cable, motor, passing wheel; the sun gear is connected to the steering wheel, the planetary gear carrier is connected to the wheel, the ring gear includes an internal gear and an external gear, and two planetary gears are provided; the sun gear is connected to the steering wheel rack Mesh with each other, and the rotation of the sun gear drives the steering wheel rack to move laterally. The variable length lever is a telescopic rod, one end of which is hinged on the steering wheel rack, and the other end is connected to the control switch. The variable length lever is provided with slot, the slidable rotating shaft can only slide up and down in the slot, the control switch is installed on the control switch rack, the passing wheel is respectively meshed with the outer gear of the ring gear and the control switch rack, and the control switch is controlled by The cable transmits the control signal to the motor, the motor meshes with the outer gear of the ring gear, the planetary gear meshes with the inner gear of the ring gear and the sun gear respectively, and the two ends of the star gear carrier are respectively hinged on the rotation shafts of the planetary gears.

Further, when the vehicle is running at a low speed, by moving the slidable rotating shaft down, the transmission ratio of the steering mechanism is reduced, and the turning sensitivity is increased.

Further, when the vehicle is running at high speed, the transmission ratio of the steering mechanism is increased by moving the slidable rotating shaft upwards, and the turning sensitivity is reduced.

The beneficial effects of the present invention are as follows:

The invention can realize the variable transmission ratio transmission of the turning mechanism of the automobile, reduce the transmission ratio of the steering mechanism at low speed, increase the sensitivity of steering, increase the transmission ratio of the steering mechanism at high speed, reduce the sensitivity, and increase the stability when driving; at the same time, No angle sensor is required, which has the advantage of low cost.

Description of drawings

Fig. 1 is a structural principle diagram of the control mechanism of the variable transmission ratio steering system of the present invention.

Fig. 2 is a structural principle diagram of the present invention when reducing the transmission ratio of the control mechanism.

Fig. 3 is a structural principle diagram of the present invention when increasing the transmission ratio of the control mechanism.

In the figure: 1-control switch, 2-control switch rack, 3-slidable shaft, 4-variable length lever, 5-steering wheel rack, 6-planetary gear carrier, 7-ring gear, 8-sun gear, 9-planetary gear, 10-control cable, 11-motor, 12-passing wheel.

detailed description

The present invention will be further explained below in conjunction with the accompanying drawings.

The structure of the control mechanism of the variable transmission ratio steering system of the present invention is as shown in Figure 1, including control switch 1, control switch rack 2, slidable rotating shaft 3, variable length lever 4, steering wheel rack 5, planetary gear carrier 6. Ring gear 7, sun gear 8, planetary gear 9, control cable 10, motor 11, passing wheel 12.

The sun gear 8 is connected with the steering wheel, the planetary gear carrier 6 is connected with the wheels, the ring gear 7 includes an inner gear and an outer gear, and two planetary gears 9 are provided.

The sun gear 8 and the steering wheel rack 5 mesh with each other, and the rotation of the sun gear 8 drives the steering wheel rack 5 to move laterally. The variable length lever 4 is a telescopic rod, one end of which is hinged on the steering wheel rack 5, and the other end is connected with the control switch 1. A slot is arranged in the variable length lever 4, and the slidable rotating shaft 3 can only slide up and down in the slot. The control switch 1 is installed on the control switch rack 2 . The passing wheel 12 meshes with the outer gear of the ring gear 7 and the control switch rack 2 respectively, and the control switch 1 transmits a control signal to the motor 11 through the control cable 10, and the motor 11 meshes with the outer gear of the ring gear 7. The planetary gears 9 mesh with the inner gear of the ring gear 7 and the sun gear 8 respectively. Both ends of the planetary gear carrier 6 are respectively hinged on the rotating shaft of the planetary gear 9 .

The steering wheel rack 5 is driven by a gear mounted on the steering wheel shaft. The control switch 1 is installed on the control switch rack 2 . The control switch rack 2 is driven by the ring gear 7 of the planetary gear mechanism. The variable length lever 4 is made up of two rods, one of which is inserted in the other, and the two rods can slide relative to each other, thereby changing the total length of the rod. Groove is arranged in the variable length lever 4, and slidable rotating shaft 3 can slide in the groove. One end of the variable length lever is connected with the steering wheel rack 5, and the other end is connected with the control switch 1. The sun gear 8 is connected with the steering wheel, the planetary gear carrier 6 is connected with the wheels, and the slidable rotating shaft 3 can only move up and down.

The working process of the control mechanism of the variable transmission ratio steering system of the present invention is as follows:

When the driver turns the steering wheel clockwise, as shown in Figure 1, the steering wheel rack moves to the right, driving the variable length lever to move to the right. Because of the blocking of the slidable rotating shaft, the other end of the variable length lever pushes the control switch to the left. The control switch generates a control signal to make the motor rotate counterclockwise, thereby driving the ring gear to rotate clockwise. At this time, the sun gear and the ring gear drive the planetary gear carrier to rotate clockwise. At the same time, the ring gear drives the control switch rack to move to the left through the passing wheel. If the driver stops turning the steering wheel at this moment, the variable length lever will no longer push the control switch to the left, the control signal disappears, and the motor stops.

When the vehicle is running at a low speed and the transmission ratio of the steering mechanism needs to be reduced to increase the turning sensitivity, the slidable shaft moves downward, as shown in Figure 2. At this time, the steering wheel rack only needs a small amount of movement to drive the control switch rack to move in a large range, so that the motor drives the ring gear to rotate greatly, thereby increasing the rotation angle of the planetary gear carrier, reducing the transmission ratio of the steering mechanism, and increasing sensitivity.

When the vehicle is running at high speed, it is necessary to increase the transmission ratio of the steering mechanism and reduce the sensitivity, the slidable shaft moves upward, as shown in Figure 3. At this time, the large-scale movement of the steering wheel rack can only drive the control switch rack to move a small amount, so that the motor drives the ring gear to rotate in a small range, thereby increasing the transmission ratio of the steering mechanism and reducing sensitivity.

In summary, the control mechanism of the variable transmission ratio steering system of the present invention can realize the variable transmission ratio transmission of the turning mechanism of the automobile, reduce the transmission ratio of the steering mechanism at low speeds, increase the sensitivity of steering, and increase the speed of the steering mechanism at high speeds. The transmission ratio reduces the sensitivity and increases the stability when driving. At the same time, no angle sensor is needed, which has the advantage of low cost.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (3)

1. A control mechanism for a variable transmission ratio steering system, characterized in that it includes a control switch (1), a control switch rack (2), a slidable rotating shaft (3), a variable length lever (4), a steering wheel tooth bar (5), planetary gear carrier (6), ring gear (7), sun gear (8), planetary gear (9), control cable (10), motor (11), passing wheel (12); the sun Wheel (8) is connected with steering wheel, and described planetary gear carrier (6) is connected with wheel, and described ring gear (7) comprises internal gear and external gear, and described planetary gear (9) is provided with two; The sun gear (8) meshes with the steering wheel rack (5), the rotation of the sun gear (8) drives the steering wheel rack (5) to move laterally, the variable length lever (4) is a telescopic rod, one end of which is hinged to the steering wheel On the bar (5), the other end is connected with the control switch (1), the variable length lever (4) is provided with a groove, the slidable shaft (3) can only slide up and down in the groove, the control switch (1) Installed on the control switch rack (2), the said passing wheel (12) meshes with the outer gear of the ring gear (7) and the control switch rack (2) respectively, and the control switch (1) passes through the control cable (10) Send the control signal to the motor (11), the motor (11) meshes with the outer gear of the ring gear (7), and the planetary gear (9) is respectively connected to the inner gear of the ring gear (7) and the sun gear (8) meshed with each other, and the two ends of the planetary gear carrier (6) are respectively hinged on the rotating shaft of the planetary gear (9). 2. The control mechanism of a variable transmission ratio steering system according to claim 1, characterized in that: when the vehicle is running at a low speed, the transmission ratio of the steering mechanism is reduced by moving the slidable rotating shaft (3) downward, increasing Turn sensitivity. 3. The control mechanism of a variable transmission ratio steering system according to claim 1, characterized in that: when the vehicle is running at high speed, the transmission ratio of the steering mechanism is increased and the transmission ratio of the steering mechanism is reduced by moving the slidable shaft (3) upward Turn sensitivity.