Patent Application
20050242644
The invention is relates to a method to act upon at least two recipients of a pneumatic system in an alternating manner, for example a massage system of a motor vehicle seat, with a pressure medium flow. In addition, the invention relates to a pneumatic circuit to execute this method.
Pneumatic control and regulation circuits are used in numerous technical applications. Thus, pneumatic methods and corresponding pneumatic circuits are used in the motor vehicle industry, for example, to adjust the otherwise standardized contour of vehicle seats to external influences or to the individual desires of the user of the motor vehicle.
A pneumatically controlled seat for a vehicle is known from U.S. Pat. No. 4,655,505, which makes it possible for the driver to vary the pressure distribution of the seat. This device includes a plurality of flexible air chambers integrated into the vehicle seat, which are connected to an air pump and a pressure sensor via a corresponding number of connecting means. Each connecting means has a valve, which can be triggered via electronic control means, which evaluate the signal from the pressure sensor.
The combined, pneumatic and electric circuit of this device permits defined pressures to be built up in the individual air chambers of the seat due to the plurality of the valves and, therefore, to increase both the comfort of the seat as well as to take the longitudinal or lateral accelerations of the vehicle into account.
In particular, the device in U.S. Pat. No. 4,655,505 permits the pressure in each individual air chamber to be varied continuously in terms of time so that an optimized pressure distribution can be adjusted or the driver experiences a massage effect due to an oscillating change in the pressure conditions in the air chambers.
An expensive electrical control and regulating unit with corresponding electronics and at least one pressure sensor as well as a central computing unit is necessary to achieve this variation in the pressure conditions of the individual air chambers of the seat in U.S. Pat. No. 4,655,505.
The objective of the present invention is realizing a method or a pneumatic circuit to act upon at least two recipients of a pneumatic system in an alternating manner with a pressure medium flow, which method makes adequate filling of the involved recipients possible in a simple, but reliable manner.
The objective is attained with the method in accordance with the invention or by the pneumatic circuit in accordance with the invention with the features of claim 1 or claim 10.
The method in accordance with the invention to act upon at least two recipients of a pneumatic system in an alternating manner, in particular a pneumatic massage system of a motor vehicle seat, with a pressure medium flow or the corresponding pneumatic circuit provides that at least one, first air cushion that serves as a recipient is filled with a gaseous working fluid, while the working fluid is actively suctioned off from at least one other, second air cushion. The method in accordance with the invention or the pneumatic circuit to execute this method improves the operation, e.g., of an air-chamber-driven massage system in a vehicle seat by replacing the passive deaeration of the cushions according to the prior art with an active deaeration. A passive deaeration is very much a function of the environmental conditions (e.g., seat design, driver weight, ambient temperature, etc.). With an active evacuation of the concerned cushions, the achievable massage effect is more greatly noticeable. In a seat massage system, which is composed of at least two air cushions that are installed in a vehicle seat, on an alternating basis one cushion is filled with air or another kind of gaseous working fluid and the air is actively suctioned off in the other cushion. Because of this suctioning off of the air, the corresponding cushion is emptied better, thereby intensifying the massage effect that is a function of the pressure difference in the concerned air cushions.
Advantageous improvements and further developments of the method disclosed in claim 1 or the pneumatic circuit described in claim 10 are possible as a result of the measures and features listed in the other claims.
The pressure in the at least one, to be-emptied air cushion can be used to advantageously fill the at least one, to-be-filled air cushion. In this case, the designation “air cushion” is not limited to the use of air as a working fluid in the pneumatic system. The term “cushion” should also be understood in a wider sense and should include at least an inflatable recipient. Such a pneumatic system can be realized with an entire series of gaseous working fluids. By actively emptying the one air cushion, the pressure in the to-be-emptied cushion can be used to fill another cushion, instead of escaping into the atmosphere as is the case with the corresponding systems of the prior art. This essentially closed operating cycle means an improvement in the efficiency of the pneumatic system as well as an energy savings when operating such a system.
In an advantageous embodiment of the method in accordance with the invention, the alternating filling of the air cushions is achieved by a reversal of the rotational direction of the pump conveying the working fluid. Using such a pump permits the concerned air cushions to be filled or emptied in an alternating manner in a very simple way. Such a pump is driven in an advantageous manner by an electric motor, whose speed and rotational direction is presettable, e.g., via a corresponding control unit.
A pneumatic system can be realized in this way, in which the final pressure in the to-be-filled recipient (air cushion) or the frequency of the working fluid acting upon the concerned recipients in an alternating manner is presettable.
Thus, for example the final pressure in the to-be-filled cushion, which determines the hardness of the vehicle seat and specifies the intensity of the massage effect, can be preset manually via corresponding operating elements. In this way, it is possible to take different users or different usage conditions of the vehicle seat into account. In addition to the desired final pressure in the air cushions, the frequency with which the air cushions are filled and emptied, for example, can also be manually adjusted and thereby adapted to the individual driving situation.
In an alternative exemplary embodiment of the method in accordance with the invention, the filling of the recipients is controlled by a control unit, which obtains information about the occupation of the seat via various detectors. Thus, for example the weight of the vehicle user, the body size or even the elapsed travel time can be detected via corresponding sensors and transmitted to the control unit. Control programs to activate the air cushions that have been adapted to the driver type and the driving situation can be selected in the control unit via correspondingly stored characteristic curves. Thus, it is possible for example to take a very long travel time into account by a slight massage effect counteracting the driver's fatigue. It is also conceivable to detect the so-called microsleep of a driver and to alert the driver to this situation by an intensified massage effect and to prevent further “nodding off.”
In one embodiment of the method in accordance with the invention, the final pressure in the at least one, to-be-filled recipient and/or the frequency of the working fluid acting upon the at least two recipients in an alternating manner is controlled or regulated by a constriction of the pressure medium flow on the pressure side of the feed pump, in particular by a throttling valve.
In an alternative embodiment the final pressure or the frequency of the action is controlled or regulated by actuating a bypass between the suction side and the pressure side of the feed pump for the working fluid.
The pneumatic circuit to act upon at least two recipients of a pneumatic system in an alternating manner with a pressure medium flow advantageously features a feed pump and connecting means, which are connected with one another in such a way that the at least one, first recipient is connected to the at least one, second recipient via the connecting means and the feed pump. An essentially closed conveyance system in which the working medium is merely transferred by pumping over is yielded in this way. In addition, the pneumatic circuit can feature a recipient that serves as a storage reservoir for the working fluid.
The suction side of the feed pump for example can be connected to at least one, first recipient, while the pressure side of the feed pump is simultaneously connected to at least one, second recipient. The reversal of the rotational direction of the feed pump permits simple pumping over of the working fluid to be realized in this way.
In another exemplary embodiment of the pneumatic circuit in accordance with the invention, a component controlling the pressure medium flow can be connected on the suction side of the feed pump with at least one recipient. A corresponding design of the controlling component makes it possible for the pressure side of the feed pump to also be connected to the same component.
Such a pressure control means can advantageously be realized as a pneumatically driven actuator, which regulates the acting upon of the recipients in an alternating manner. In this case, it is possible to use a simple feed pump without the possibility of the reversal of rotational direction.
A component with a valve that can be regulated and switched can be used as the pressure control means in a simple and therefore advantageous manner.
The feed pump can be embodied advantageously as a vane-cell pump, in particular as a vane-cell pump with means to reverse the rotational direction. In another advantageous exemplary embodiment of the pneumatic circuit, the connecting means between the feed pump and the recipients features an output valve, which opens the connecting line when a specific pressure limit is reached on the suction side of the pump in order to supply additional working fluid to the system.
Such a pneumatic system can be installed in an advantageous manner in a vehicle seat, in particular the seat of a motor vehicle, so that a massage effect can be realized in the vehicle seat with the aid of the method in accordance with the invention, which expands vehicle comfort as well as increases travel safety.
With the method in accordance with the invention or the pneumatic circuit in accordance with the invention to execute this method it is possible to improve the functioning of a massage system, in particular a massage system for a vehicle seat, by replacing the passive deaeration of the recipients with an active deaeration. As a result, it is possible to realize a massage system that is largely independent of the environmental conditions.
Exemplary embodiments of the pneumatic circuit in accordance with the invention are depicted in the drawing and are supposed to be explained in greater detail in the following description. The figures of the drawing, the description thereof as well as the claims contain numerous features in combination. A person skilled in the art will also observe these features individually and combine them into additional, meaningful combinations.
The drawing shows:
An adjustable valve 30, which can be arranged in a bypass 32 between the suction side 18 and the pressure side 20 of the feed pump 22, can regulate the pumping capacity of the pump 22. To do so, the adjustable valve 30 can possess a control for example, which is connected with the central control unit of the pneumatic circuit, which also regulates the electric motor 24 of the feed pump 22.
Alternatively or in addition, a control valve 34 can be arranged on the pressure side of the feed pump. Because of the corresponding regulation, the pressure in the cushions and the frequency of the working fluid acting upon the cushions can be influenced.
In the present exemplary embodiment in
Pressure sensors, which can monitor the pressure in the to-be-filled recipients, are located in the recipients, the connecting lines or even in the feed pump. The control unit can also prescribe a specific feed time for the feed pump 22 for example, which, with a known pumping capacity of this pump, determines the final pressure in the to-be-filled recipient. In addition, this final pressure can also be adjusted via the control valves 30 or 34, for example. If the actuator 36 changes its position, then the filled recipient 10 is now connected to the suction side of the feed pump 22 so that this recipient is now actively emptied and the working fluid is pumped over into the now to-be-filled recipient 12 via the feed pump 22.
By prescribing the change frequency for the actuator 36 setting, the frequency of the working fluid acting upon the two recipients in an alternating manner can thus be preset for example. The actuator 36 can be operated mechanically, for example, or else even pneumatically.
The pneumatic system depicted in
One the one hand, the second output channel 40 of the actuator 36 is coupled via connecting means 58 and a constrictor 60 to the second recipient 12 and, on the other hand, via connecting means 62 and a constrictor 64 to a second reservoir 66. The supply line to the reservoir 66 also features a time-lag element 68 and a reflux valve 70 for deaerating the reservoir. Like the reservoir 52, the reservoir 66 is connected to the actuator 36 via a device 72, but on the opposite side.
In its interior, the actuator 36 features continuous channels, which produce the connection between the pressure side 20 with one of the connecting means 42 or 58 as well as a connection of the suction side 18 of the feed pump 22 with the respective connecting means 42 or 58 not connected with the pressure side. The mobility of the actuator 36 is regulated by a counter device 76, which is depicted schematically as an elastic spring in
The functioning of the pneumatic circuit in accordance with the invention shall be described in more detail in the following in accordance with the exemplary embodiment in
In this alternatively possible setting of the actuator 36 that is not depicted in
A portion of the working fluid conveyed by the feed pump is supplied to the working chamber 66 via the connecting means 62 and the time-lag constrictor 64. The pressure in the second working chamber 66 now rises in accordance with the adjustment of the constrictor 64, while the recipient 12, which is the described case may be another inflatable air cushion, is pumped up. The increasing pressure in the working chamber 66 is transmitted to the pneumatic actuator 36 via a corresponding device 86 so that a force results against the spring force of the counter spring 76. If this force is sufficiently great to overcome the locking force of the actuator 36 due to the counter device 76, then a sufficiently great pressure has built up in the working chamber 66; thus, the actuator will be pushed back into its first setting (shown in
Thus, a complete cycle of the method in accordance with the invention to act upon at least two recipients of a pneumatic system in an alternating manner with a pressure medium flow is concluded and the system automatically begins again with the filling of the recipient 10 as described above.
Because of the alternating filling or emptying of the concerned air cushions, a system based on this invention in the seat of a motor vehicle permits seating comfort to be improved and relief for the spinal column to be achieved due to the massage effect that ensues. The frequency of this movement can be adjusted via the setting of the relative constrictor sizes 64 or 48, the extent of the volumes involved and not the least also via the required pressure medium flow. It is also easily possible for the user himself, for example, to individually adapt the frequency of the movement via direct adjustment of the strength of the counter device 76.
A small-capacity compressor, e.g., a vane-cell pump or even a diaphragm pump, can be used to circulate the working fluid of the device.
In the exemplary embodiment in
In the exemplary embodiment in
The method in accordance with the invention to act upon a pneumatic system in an alternating manner with a pressure medium flow or the corresponding pneumatic circuit to execute this method is not limited to the exemplary embodiments depicted in the figures. In particular, the method or the associated device is not limited to the use of air as the working medium. Even if air is preferred as an easily available and therefore cost-effective working medium, other gaseous working fluids are also possible. The use of water or other liquid working fluids involves the problem that a leak in the system can lead to a saturation of the vehicle seat so that the use of liquid working fluids shall be refrained from.
The method in accordance with the invention and the corresponding pneumatic circuit are not limited to the application in a massage system and in particular not limited to the use in the vehicle seats of a motor vehicle. On the contrary, such a pneumatic system can be used in a multiplicity of technical applications.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10238240.9 | Aug 2002 | DE | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/DE03/02508 | 7/25/2003 | WO | 2/22/2005 |
