JPH02216337A - Movable step device for vehicle - Google Patents

Abstract

PURPOSE:To prevent damage of a step plate by stopping its driving mechanism in detecting the step plate for its interference with an obstacle when the step plate movable between high and low positions is lowered toward the low position. CONSTITUTION:When an on-off getting person opens a door in a vehicle, a motor 17 operates pulling toward a direction C a link 19 by a link 18, and a step plate 8, supported by links 4, 5, is protruded (condition as shown by the drawing) to the outside. Here, because turning centers 12, 13 of brackets 10, 11 are positioned in a lower part from turning centers 6, 7 of the links 4, 5, the plate 8 is placed in a lower part from a storage position when the motor 17 is inoperative. Now the plate 8 halfway its lowering interferes with an obstacle of stones and rocks or the like, when the motor 17 generates a flow of overcurrent, a control device decides the plate to interfere with the obstacle, reversing the motor 17 lifting the plate 8 to the storage position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a step for a vehicle that facilitates getting on and off the vehicle.

(Prior Art) Conventionally, a step mechanism for a vehicle is known in which a step plate is supported movably in the vertical direction of the vehicle with respect to a vehicle chassis frame.

Furthermore, a movable step device for a vehicle is known in which the step plate is moved by a drive mechanism such as a hydraulic cylinder and the step plate is automatically lowered to a lower position only when, for example, a vehicle door is opened.

Such a movable step device for a vehicle is disclosed in, for example, Japanese Patent Application Laid-open No. 58
It has been proposed in Publication No.-39543 and the like.

(Problem that the invention sought to solve) However, in the conventional device, if there is an obstacle such as a rock under the step plate and the step plate cannot move to a predetermined low position, the step plate or drive mechanism There was a problem in that excessive force was applied to the step plate and the life of the drive mechanism was shortened.

Therefore, in the present invention, the problems of such conventional devices are solved, and a common feature is to prevent excessive force from being applied to the step plate or the drive mechanism when the step plate cannot move to a predetermined low position. This was considered a technical issue.

[Structure of the Invention] (Means for Solving the Problems) The technical means taken to solve the above-mentioned technical problems is a system that is attached to the chassis frame of a vehicle and installed between a predetermined high position and a predetermined low position. A movable step device for a vehicle, comprising: a step plate movable; and a drive mechanism for moving the step plate; The present invention further includes a detection means for detecting that the step plate has hit an obstacle, and a control device for stopping the lowering of the step plate when the step plate has hit the obstacle.

(Function) If the step plate hits an obstacle such as a rock while descending to a lower position,
The presence of the obstacle is detected by the detection means. Then,
The control device operates to stop the operation of the drive mechanism. When the operation of the drive mechanism is stopped, no further force is transmitted to the step plate or the drive mechanism. Therefore,
This prevents excessive force from being applied to the step plate or drive mechanism.
The desired technical task is achieved.

(Example) An embodiment of the present invention will be described based on the accompanying drawings.

First, the mechanical portion of the movable step device of this embodiment will be explained with reference to FIGS. 1, 2, 3, and 4. A bracket 2 is fixed to a chassis frame l of a vehicle with bolts 3. Projections 2a, 2b, 2c, and 2d, which are inclined with respect to the chassis frame 1, are integrally formed at the upper and lower parts of the bracket 2. (2d is not shown) This protrusion 2a
and 2c, a link 4 having a U-shaped cross section is provided with a protrusion 2a,
One end is rotatably supported by a shaft 6 in the longitudinal direction of the vehicle so as to be parallel to 2c. In addition, the protrusions 2b, t
A link 5 having a U-shaped cross section is located between the projections Zb, ! One end is pivotally supported by a shaft F so as to be parallel to d so as to be rotatable in the longitudinal direction of the vehicle.

The step plate 8 is fixed to a bar 9 with screws or the like, and a bracket 1 (1, 11) is fixed to both ends of the bar 9 by welding or the like. One end of the bracket 1G has a U-shaped cross section. Furthermore, it is parallel to the link 4.The other end of the link is supported by a shaft 12 on one end of the bracket 10 so as to be rotatable in the longitudinal direction of the vehicle.One end of the bracket 11 has a U-shaped cross section. has become,
Furthermore, it is parallel to link 5. This bracket 11
The other end of the link 5 is rotatably supported by a shaft 13 at one end of the link 5 so as to be rotatable in the longitudinal direction of the vehicle. As a result of the above, the link 4.5 is inclined by a predetermined angle with respect to the chassis frame l. Further, the step plate 8 is arranged parallel to the rocker panel 15 of the vehicle body 14.

A protrusion 2e is integrally formed on the bracket 2, and a motor box 16 is fixed to this protrusion 2m. A motor 1) is arranged within this motor box 16. A link 18 is connected to the shaft 22 of this motor box 16. One end of a link 19 is rotatably supported by a pin 20 at one end of the link 18 . The other end of the link 19 is rotatably supported by a pin 21 on a protrusion 4a formed integrally with the link 4.

Next, the general operation of the device of this embodiment will be explained.

When the vehicle door (not shown) is closed in FIGS. 1 and 2, the motor 17 is not operating and the step plate 8 is housed under the rocker panel 15. At this time, the link 4°5 is parallel to the step plate 8. When a passenger opens the door of the vehicle to get on or off the vehicle, the motor 17 operates and the link 18 rotates clockwise. As a result, the link 19 is pulled in the direction C in the second diagram. For this reason, the links 4.5 are connected to the axes 6 and 6, respectively.
The step plate 8 rotates clockwise around the rocker panel 7, and as shown in FIGS. 3 and 4, the step plate 8 projects outward from the rocker panel 15. At this time, the bracket 10.11 rotates counterclockwise about the shaft 11.13, so the step plate 8 rotates while always maintaining a position parallel to the rocker panel 15. Furthermore, since the center of rotation 14.13 of the bracket 10.11 is located below the center of rotation 6°7 of the link 4.5, the step plate 8 is located below the storage position of the motor 17 when it is not in operation. Placed. As a result, the step plate 8 is placed at a position where passengers can easily get on and off the vehicle. The motor 17 is activated when the step plate 8 reaches a predetermined low position, that is, the link 1
It detects when 9 is pulled to the maximum and stops the operation. As a result, the step plate 8 is held at the getting on/off position.

When the passenger finishes getting on and off the vehicle and closes the door of the vehicle, the motor 17
is activated again and presses link 21. This will cause link 4
．． 5 rotates counterclockwise around an axis 6.7, and the step plate 8 is housed in the lower part of the rocker panel 15.

The motor 17 detects when the step plate 8 reaches a predetermined high position, that is, when the link 19 is pushed to the maximum, and stops its operation. As a result, the step plate 8 is held in the retracted position by the link 19.

As mentioned above, the step plate 8 is connected to the rocker panel 1.
5, the link 4.5 is parallel to the step plate 8, so even if the length of the link 4.5 is increased, it can be stored at a high position with minimal storage space. . Therefore, by increasing the length of the link 4.5, the amount of protrusion of the step plate 8 can be increased.

If the amount of protrusion of the step plate 8 can be increased, the getting on/off position of the step plate 8 can be optimized, which makes it easier for people to get on the vehicle. Also, motor box 16
Since the link 4.5 is held by one bracket 2, it can be easily assembled to the chassis frame, and since the assembly is performed with high precision, it does not affect the operation of the step mechanism.

Hereinafter, with reference to FIGS. 5 and 6, motor box 1 will be explained.
6 will be explained in detail. Figure 5 shows motor box 1
6 is a cross-sectional view taken along line AA in FIG. 5.

A worm gear 31 is fixed to the rotation shaft of the motor 17. Further, a worm wheel 32 is engaged with the worm gear 31. The worm wheel 32 is coupled to the shaft 22, and the worm wheel 32 and the shaft 22 rotate together. The worm wheel 32 is made of resin such as polyacetal, and a substantially circular plate and a conductive plate 33 are bonded onto the worm wheel 32.

This conductive plate 33 has two notches 33a, 3
3b is provided. Three electrical contacts $4,35,36 are in contact with the conductive plate 33. When the step plate 8 is in the getting-on/off position, there is no electrical continuity between the electrical contacts 34 and 35. Further, when the step plate 8 is in the retracted position, electrical contact between the electrical contacts 35 and 36 becomes non-conductive. When the step plate 8 is neither in the boarding position nor in the storage position, between the electrical contacts 34 and 35 and between the electrical contacts 35 and 3
6 are both electrically conductive.

These electrical contacts 34, 35, 36 serve to control the motor 17 by a control circuit 70 shown in FIG. The control circuit 70 will be explained below with reference to FIG.

A battery 85, a courtesy switch 84, and a motor box 16 are electrically connected to the control circuit 70. The courtesy switch 84 is a vehicle door (not shown)
This is a switch that detects the opening and closing of the vehicle door, and its contacts open only when the vehicle door is fully closed.

The control circuit 70 includes a power supply control circuit lot and a forward/reverse control circuit 1.
02, an overcurrent detection circuit 103 and a protection circuit 104.

The power supply control circuit 101 is a circuit that controls power supply to the control circuit 70. The power supply control circuit 101 supplies power to the control circuit 7G while the vehicle door is opened and the courtesy switch 84 is closed, and while the step plate 8 is in a position other than the retracted position. Conversely, when the vehicle door is closed,
While the courtesy switch 84 is open and the step plate 3 is in the retracted position, power supply to the control circuit 70 is stopped.

The forward and reverse rotation control circuit 102 is a circuit that controls the rotation direction of the motor 17. The forward/reverse control circuit 102 controls the motor 17 when the vehicle door is opened and the courtesy switch 84 is closed.
is rotated in the normal direction to lower the step plate 8 toward the getting-on/off position. Conversely, when the vehicle door is closed and the courtesy switch 84 is opened, the motor 17 is reversed to raise the step plate 8 toward the retracted position.

The overcurrent detection circuit 103 is a circuit that detects the magnitude of the current flowing through the motor 17 when the step plate 8 descends toward the boarding/exiting position, and compares it with a predetermined value set in advance. Overcurrent detection circuit l.

3 is equipped with an internal integration circuit 90 in order to distinguish between an instantaneous overcurrent that flows when the motor 17 starts up and a continuous overcurrent that flows when the step plate 8 hits an obstacle. The overcurrent detection circuit 103 outputs an electric signal indicating that "an obstacle is present" when the chip plate 8 hits an obstacle. The forward/reverse control circuit 102 stops energizing the motor 17 when it receives an electric signal indicating "obstruction present" from the overcurrent detection circuit IO3.

The protection circuit 104 is a circuit that protects the control circuit 7 from surge current and reverse voltage.

The operation when the vehicle door is opened will be described below. When the vehicle door is opened, the contacts of the courtesy switch 84 are closed and the control terminal 86a of the power switch circuit 86 becomes "L".At this time, the power switch circuit 8
6 connects the battery 85 and the power supply circuit 87, and supplies constant voltage power Vcc to each circuit of the control circuit 7G. Therefore, when the vehicle door is opened and the courtesy switch 84 is closed, the control circuit 70 begins to operate.

When the courtesy switch 84 is closed, the output of the inverter 71 becomes "H". At this time, since the motor 17 is not started, no voltage is generated in the detection resistor 79, and the amplifier 7
The output of the inverter 7 remains "L II". Therefore, the output of the inverter 7 is "H", and the output of the integrating circuit 9G is 11H.
", the output of the inverter 76 is "L", and the output of the inverter 73 is "'H". As a result, Nantes Gate 72
Since both of the input terminals of the input terminal become "H", the output of the Nandt gate 72 becomes 'L°°. At the same time, the output of the inverter 74 is l L l", and the output of the inverter 75 is "
becomes H″.

While the output of the Nantes gate 72 is °“L 11, the relay 8
A current flows through the coil 8 from the power supply Vbd through the contact 35, the conductive plate 33, and the contact 34, and the contact of the relay 88 is switched to the power supply Vb side. From this moment, current begins to flow through relay 83, motor 17, relay 89, and resistor 79, causing motor 17 to rotate forward and step plate 8
begins to descend toward the entry/exit position.

When the step plate 8 leaves the storage position, the contact 35
The contact 36 becomes conductive, and the power supply Vbd is applied to the coil of the relay 89.
is connected. However, since the output of inverter 75 is 11 HII, the contact of relay 89 is held on the ground side.

Thereafter, when the step plate 8 reaches the getting-on/off position, the contacts 34 and 35 become non-conductive, and the current flowing to the coil of the relay 88 is cut off.

As a result of the second result, the contact point of the relay 88 is switched from the power supply VB side to the ground side, and the motor 17 is stopped.

In this way, when the vehicle door is opened and the courtesy switch 84 is closed, the control device 70 controls the step plate 8 to be lowered toward the boarding/exiting position.

The operation when the vehicle door is closed will be described below. When the vehicle door is closed, the contacts of the courtesy switch 84 are closed. At this time, the output of the inverter 71 is "'H"
°°, but the control terminal 86a of the power switch circuit 86 is held at "L11" by the output of the inverter 82. At this time, the output of the inverter 74 is "L11".
I Hl", and the output of the inverter 75 becomes "L".

While the output of the inverter 75 is "L°", current flows from the power supply Vbd to the coil of the relay 89 through the contacts 35 and 36. As a result, the contact of the relay 89 switches from the ground side to the power supply Vb side. From the moment the current flows through relay 8
9, motor 17 and relay 88 begin to flow, motor 17 reverses and step plate 8 begins to rise towards the retracted position.

When the step plate 8 leaves the getting on/off position, the contact point 34
The contact 35 becomes conductive, and the power supply Vbd is applied to the coil of the relay 88.
is connected. However, since the output of the Nant gate 72 is Hu, the contact of the relay 88 is held on the ground side.

Thereafter, when the step plate 8 reaches the retracted position, the contacts 35 and 36 become non-conductive, and the current flowing to the coil of the relay 89 is cut off.

As a result, the contact of the relay 89 is switched from the electric Bvb side to the ground side, and the motor 17 is stopped.

In this way, the control device 7G controls the step plate 8 when the vehicle door is closed and the courtesy switch 84 is opened.
control to raise it toward the storage position.

The automatic retracting operation when the step plate 8 hits an obstacle while moving toward the boarding/exiting position will be described below.

Only while the vehicle door is opened and the step plate 8 is lowered toward the entry/exit position, current flows through the resistor 79 and a voltage is generated across the resistor 79. This voltage has a magnitude proportional to the magnitude of the current flowing through the motor 17. The voltage generated across resistor 17 is applied to inverter 77 after being amplified by amplifier 78 .

When the step plate 8 hits an obstacle such as a rock and stops descending, the motor 17 becomes overloaded and an overcurrent flows through the motor 17. At this time, when the magnitude of the current flowing through the resistor 79 exceeds a predetermined value, the output voltage of the amplifier 78 exceeds the dark value of the inverter 7, and the output of the inverter 77 becomes
It becomes L”.

When the output of the inverter 77 shows "L" for a predetermined time or more,
That is, when the motor 17 is maintained in an overloaded state for a predetermined period of time or more, the output of the integrating circuit 9G changes to "L" and the output of the inverter 76 changes to "H". At this time, the output of the inverter 73 is "L".

As a result, the output of the AND gate 72 becomes ``H'', and the current flowing through the coil of the relay 88 disappears. Therefore, the contact of the relay 88 is switched from the voltage 1vb side to the ground side. At the same time, the output of the inverter 73 changed to °"L", so the coil of the relay 89 was connected to the power supply V.
From bd to power contact 35, conductive plate 33, electrical contact 3
A current flows through 6, and the contact of relay 89 is switched from the ground side to the power supply VB side. Therefore, the motor 17 begins to rotate in reverse.

At this time, no current flows through the resistor 79, but since the output of the inverter 76 becomes "H", the output of the amplifier 7B is latched and self-maintained at "°H".

Therefore, the motor 17 continues to rotate in reverse and the step plate 8 continues to rise towards the retracted position.

In this way, if the step plate 8 hits an obstacle while moving toward the boarding/exiting position and the motor 17 is kept in an overloaded state for a predetermined period of time or more, the step plate 8 is immediately stopped from descending, and at the same time the step plate 8 is stopped. 8 begins to rise.

By the way, the self-holding state of the amplifier 78 is released by closing the vehicle door. That is, when the vehicle door is closed and the courtesy switch 84 is opened, the output of the inverter 71 is "L" and the output of the inverter 74 is +H.
++, the output of the inverter 75 becomes "L" and the output of the inverter 77 is forced to "H"°. If this state continues for the predetermined time mentioned above, the output of the integrating circuit 90 will go high.
°, the output of the inverter 76 becomes "L'" and the self-holding state of the amplifier 78 is released. After this, the control circuit 7
0 returns to the initial state before detecting the obstacle.

Even if the control circuit 70 returns to the initial state, the step plate 8 continues to rise toward the retracted position because the control circuit 70 executes the control described above when the vehicle door is closed.

According to the control circuit 70 having such a configuration, if the door of the vehicle is closed and opened after the step plate 8 hits an obstacle, the step plate 8 can be lowered again. It can be moved faithfully according to the will of the occupants.

In the device of this embodiment, the fact that the step plate 8 hits an obstacle such as a rock is detected based on the magnitude of the current flowing through the motor 17. However, the obstacle detection may be performed by other detection means. For example, detection may be performed using a pressure-sensitive switch, touch sensor, optical sensor, ultrasonic sensor, radar, or the like.

〔Effect of the invention〕

According to the present invention, when the step plate hits an obstacle such as a rock while descending toward a lower position, the control device operates to stop the operation of the drive mechanism.

Therefore, it is possible to prevent excessive force from being applied to the step plate and the drive mechanism, and damage to the step plate and the drive mechanism can be prevented.

Further, since excessive force is not transmitted to the step plate, it is safe even if a human body, luggage, etc. are caught under the step plate while the step plate is lowered.

[Brief explanation of the drawing]

Figure 1 is a view showing the stored state of the step plate, Figure 2 is a view shown in the direction of arrow A in Figure 1, Figure 3 is a view showing the protruding state of the step plate, and Figure 4 is shown in the direction of arrow B in Figure 3. It is a diagram. FIG. 5 is a sectional view of the motor box. FIG. 6 is a sectional view taken along the line AA in FIG. 5. FIG. 7 is a block diagram depicting the control circuit. ■...Chassis frame, 2.10.11...Bracket, 3.20.21...Bin, 4.5,18.19...Link, 6,7. 12. 13... Axis, 8... Step plate, 9... Bar 14... Vehicle body, 15... Rocker panel, 17... Motor box (drive mechanism), 18... Motor, 22 ... shaft, 70 ... control circuit (control device), 101 ... power supply control circuit, 102 ... forward/reverse control circuit, 1G! ...Overcurrent detection circuit (detection means).

Claims (3)

[Claims] (1) A chassis frame of a vehicle, a step plate attached to the chassis frame and movable between a predetermined high position and a predetermined low position, a drive mechanism for moving the step plate, and the drive mechanism detecting means that operates while the step plate is being lowered toward the predetermined low position and detects that the step plate has hit an obstacle; A movable step device for a vehicle, comprising: a control device that stops the step plate from lowering when the step plate is lowered. (2) The control device is characterized in that if the step plate hits an obstacle while descending toward a lower position, the control device further raises the step plate toward a higher position after stopping. The movable step device for a vehicle according to claim (1). (3) The movable step device for a vehicle according to claim (2), further comprising door opening/closing detection means for detecting the opening/closing state of the vehicle door, wherein the control device detects whether the vehicle door is opened while the step plate is rising. A movable step device for a vehicle, characterized in that when the vehicle is moved, the step plate is lowered toward a lower position.