JP2004345498A - Opening and closing drive device of opening and closing body for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an opening and closing drive device of an opening and closing body for a vehicle capable of easily detecting whether a thrust of an opening direction energizing means is sufficient or not. <P>SOLUTION: This opening and closing drive device of the opening and closing body for the vehicle is constituted by providing an opening and closing driving force generator 5 and the opening direction energizing means (gas stay 4) made of a fluid pressure sealing cylinder between a car body 2 and the opening and closing body (tail gate 1) and is devised to hold a totally opening position of the opening and closing body only by energizing force of the opening direction energizing means, internal pressure of the opening direction energizing means is detected, and opening door drive by the opening and closing driving force generator is not practiced when an internal pressure detected value is lower than a specified value in full closure of the opening and closing body. Consequently, it is possible to estimate the thrust of the opening direction energizing means from the internal pressure of the opening direction energizing means and accordingly, it is possible to easily avoid lowering of usability of the opening and closing body due to thrust shortage of the opening direction energizing means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a drive device for automatically opening and closing a vehicle opening / closing body using, for example, an electric motor.
[0002]
[Prior art]
A tailgate that opens in a rearward opening surface, such as a wagon vehicle, tends to be relatively heavy, and requires a large opening operation force. Therefore, it is common to provide a so-called gas stay composed of a cylinder filled with oil and gas for assisting the operation force in the opening direction and generating a holding force in the open state.
[0003]
In this gas stay, the thrust for holding the tailgate in the open position may become insufficient due to a change in the weight of the tailgate, a change in the rotational resistance of the hinge portion, a change in the ambient temperature, or the like.
[0004]
As a technique for coping with such inconvenience, an opening / closing drive device using a motor with a speed reducer is provided between the opening / closing body and the vehicle body, and when it is detected that the opening / closing body has closed (moved down) by its own weight. Japanese Patent Application Laid-Open No. 2001-107642 proposes a device in which a clutch is connected, and the closing force due to its own weight is stopped by applying the resistance force of a motor with a speed reducer to an opening / closing body.
[0005]
[Patent Document 1]
JP 2001-107642 A [0006]
[Problems to be solved by the invention]
However, according to the configuration of the prior art, a motor with a speed reducer is suddenly connected to the opening / closing body that has begun to close by its own weight, and is immediately stopped, so that an excessive load due to the inertia of the opening / closing body acts on the drive system. There was a risk of doing so. In addition, since it is necessary to constantly monitor that the opening / closing body is closed by its own weight, the control circuit of the opening / closing drive tends to be complicated.
[0007]
The present invention has been devised to solve such a problem of the related art, and its main object is to make it possible to easily detect that the thrust of the opening direction urging means is slightly insufficient, An object of the present invention is to provide an opening / closing drive device for a vehicle opening / closing body configured so that the opening / closing body does not fall into a state of closing by its own weight from a fully open position.
[0008]
[Means for Solving the Problems]
In order to achieve such an object, according to the first aspect of the present invention, an opening and closing mechanism is provided between a vehicle body (2) and an opening / closing body (tailgate 1) provided on the vehicle body so as to be capable of turning vertically. A driving force generator (5) and an opening direction urging means (gas stay 4) comprising a fluid pressure sealing cylinder are provided, and the fully open position of the opening / closing body is held only by the urging force of the opening direction urging means. An opening / closing drive device for a vehicle opening / closing body having the above structure includes an internal pressure detecting means (11) of an opening direction urging means, and when the detection value of the internal pressure detecting means falls below a predetermined value when the opening / closing body is fully closed. In this case, the door opening drive by the opening / closing driving force generator is not executed.
[0009]
With this configuration, it is possible to detect whether or not the thrust of the opening direction urging means is sufficient simply by monitoring the internal pressure of the opening direction urging means. The self-weight closing door of the body can be easily avoided.
[0010]
In particular, according to the configuration of claim 2, the predetermined value is determined in consideration of the inclination of the vehicle and the temperature of the sealed fluid, and the opening direction urging means is determined not to be able to hold the fully open position of the opening / closing body. If the value is a predetermined value, it is possible to appropriately set a predetermined determination value.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
[0012]
FIG. 1 shows a main part of a tailgate of a wagon or the like to which the present invention is applied. The tailgate 1 is supported by the vehicle body 2 with a hinge shaft 3 extending in the left-right direction of the vehicle body 2, and the opening at the rear end of the vehicle body is opened and closed by pivoting its free end in the vertical direction. ing.
[0013]
Between the outer edge of the tailgate 1 and the inner edge of the vehicle body opening, the tailgate 1 is propelled from a certain opening angle by its thrust by a sealing pressure in a cylinder set to balance the weight of the tailgate 1. A known gas stay 4 is provided which urges in the opening direction and exerts a holding force in a fully opened position.
[0014]
The opening / closing drive device 5 includes a pinion 6 that is driven to rotate by a motor with a reduction gear (not shown), and a rack 7 that meshes with the pinion 6 and is driven in the front-rear direction of the vehicle body 2. The rotational force is converted to the thrust of the rack 7 and the thrust is applied to the tailgate 1 via the link 8 to drive the tailgate 1 to open and close. Needless to say, the configuration of the opening / closing drive device 5 is not limited to the rack / pinion mechanism.
[0015]
According to the above configuration, in the region from the fully closed position of the tailgate 1 to a certain opening angle A, the thrust of the gas stay 4 is opened due to the positional shift between the rotation center of the gas stay 4 and the rotation center of the tailgate 1. The region that does not contribute as an auxiliary force, that is, the region up to the angle A, is driven to open only by the torque of the motor with a speed reducer applied to the pinion 6.
[0016]
When the opening angle A is exceeded, the thrust of the gas stay 4 is applied as the door opening assist force, and the torque load on the motor with a speed reducer is reduced (region B). If the opening angle is further increased, the door can be held open only by the thrust of the gas stay 4, and when the angular position C is reached, the current to the motor with the speed reducer is cut off and the clutch is disengaged, etc. The transmission of the driving force given to the pinion 6 to open the pin 1 is cut off, and the holding force at the fully open position depends on the thrust of the gas stay 4.
[0017]
In such a configuration, when the holding force of the open position with respect to the tailgate 1 is insufficient due to a change in the weight of the tailgate 1, a change in the rotation resistance of the hinge shaft 3, a change in the ambient temperature, or the like, the tailgate 1 is naturally moved by its own weight. Could be closed.
[0018]
In order to deal with such inconvenience, in the present invention, as shown in FIG. 2, the internal pressure of the gas stay 4 is detected by a pressure sensor 11, and the internal pressure value is input to a pressure determination circuit 12, and the gas stay 4 When it is determined that the gate 1 cannot be held at the fully open position, a command to stop the door drive control is issued to the motor drive circuit 13 so that the electric motor 14 does not drive the pinion 6. This avoids a situation in which the natural closing of the tailgate 1 due to its own weight can occur.
[0019]
By the way, the gas stay 4 is configured such that oil mixed with gas is sealed in the cylinder 15 at a predetermined pressure, and the piston rod 16 is moved from the cylinder 15 to Thrust in the pushing direction is generated. According to this, as the piston rod 16 extends, the internal volume of the cylinder 15 increases by the amount of the piston rod 16, so that the internal pressure decreases. The volume change of the cylinder 15 at this time is absorbed by the compressibility of the gas mixed in the oil. That is, as shown in FIG. 3, since the internal pressure value of the cylinder 15 becomes minimum when the piston rod stroke of the gas stay 4 is maximum, it is presumed that this minimum value cannot maintain the weight of the tailgate 1 at the fully open position. The judgment value is set by the internal pressure at the time when the stroke is minimum.
[0020]
Even if the gas stay 4 is normal, since the fluid viscosity generally increases at low temperatures and the thrust decreases, and the force required to hold the door open due to the effect of gravity increases on a slope, even if the gas stay 4 is normal, It is preferable to define the condition under such a condition that the thrust required for holding the door open is maximized. In other words, the thrust required to hold the tailgate 1 at the fully open position differs depending on the vehicle attitude (inclination) and the ambient temperature, so that by setting such conditions, the determination value can be set appropriately.
[0021]
【The invention's effect】
As described in detail above, according to the present invention, it is possible to determine whether the thrust of the gas stay is sufficient only by monitoring the internal pressure of the gas stay as the opening direction urging means provided in the opening / closing drive device. It is possible to easily prevent the usability of the tailgate from being reduced due to insufficient thrust of the gas stay without complicating the control circuit and the like. In particular, it is possible to predict that the thrust of the gas stay will be insufficient before the opening direction drive is performed, compared to the conventional one where the gas stay malfunctions after turning off the driving force. The gate does not move closed by its own weight. Therefore, it is not necessary to configure each part so as to withstand the overload when the tailgate is moved by its own weight closing door, so that it is not necessary to set the strength of each part excessively, which is also effective in promoting the downsizing of the opening / closing drive device. It is a target.
[Brief description of the drawings]
FIG. 1 is a schematic side view of a rear part of a wagon to which the present invention is applied. FIG. 2 is a block diagram showing the configuration of the present invention. FIG. 3 is a graph showing the relationship between cylinder internal pressure and piston rod stroke. ]
DESCRIPTION OF SYMBOLS 1 Tail gate 2 Body 3 Hinge shaft 4 Gas stay 5 Opening / closing drive 6 Pinion 7 Rack 8 Link 11 Pressure sensor 12 Pressure judgment circuit 13 Motor drive circuit 14 Electric motor

Claims (2)

An opening / closing driving force generating device and an opening direction urging means including a fluid pressure sealing cylinder are provided between a vehicle body and an opening / closing body provided on the vehicle body so as to be capable of turning vertically. An opening / closing drive device for a vehicle opening / closing body configured to hold a fully open position of the opening / closing body only by the urging force of the urging means,
It has an internal pressure detecting means of the opening direction urging means, and when the detection value of the detecting means is less than a predetermined value when the opening / closing body is fully closed, the door driving by the opening / closing driving force generator is not executed. An opening / closing drive device for a vehicle opening / closing body. The predetermined value is set in consideration of the inclination of the vehicle and the temperature of the sealed fluid, and is a minimum value at which it is determined that the opening direction urging unit cannot hold the fully open position of the opening / closing body. The opening / closing drive device for a vehicle opening / closing body according to claim 1.

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