The invention relates to a device for dispensing a pressurized material.
In the state of the art, it is known to use devices for dispensing a liquid material, which devices present two chambers separated by a piston.
Such devices comprise a first chamber containing a gas generator and a second chamber in which the liquid for dispensing is present, the first and second chambers being separated by the piston.
In those devices, the gas generator is initially actuated in order to put the first chamber under pressure. This pressure rise created in the first chamber is transmitted by the piston to the liquid, thereby enabling the liquid to be dispensed to the outside of the device. While the liquid is being delivered, the piston moves in said device and the volume of the second chamber decreases progressively. The piston moves until it comes into abutment against the end wall of the device, when dispensing of the material terminates. In that type of device the piston at the end of its stroke serves to provide sealing for the system and the inside volume of the device thus remains under pressure. This remnant pressure can be a drawback under certain circumstances. In addition, with such systems, when a pipe is connected to the outlet of the device, the pipe remains full of liquid. The liquid present in the pipe does not participate in the desired function, thereby reducing the effectiveness of the device.
It would therefore be desirable to provide a device in which the inside volume can be depressurized at the end of dispensing the material, and that presents improved effectiveness by enabling the residual liquid to be purged.
Solutions have been proposed in the state of the art for this purpose. Nevertheless, those solutions can be relatively complex as a result of integrating a significant number of additional elements and of requiring certain additional steps to be performed in order to fabricate such devices, or they may present problems of reliability by presenting an untimely loss of sealing between the two chambers when the device is subjected to external mechanical stresses or when the liquid expands under the effect of heat.
The invention seeks to solve the above-mentioned problems of prior art devices.
To this end, in a first aspect, the invention provides a device for dispensing a pressurized material, the device comprising a body defining a pressurizing chamber containing a gas generator, and a tank containing the material to be dispensed, said tank being defined by an end wall having an outlet orifice, the device further comprising a piston configured to move inside the body, the piston separating the pressurizing chamber from the tank, the gas generator being configured to trigger the dispensing of the material to the outside of the body through the outlet orifice by causing the piston to pass from a material-storage, first position to an end-of-material-dispensing, second position in which the piston faces the end wall;
the piston, when in the first position, presenting a housing that is closed by a fragile portion beside the pressurizing chamber and that is open beside the tank, the housing containing a striker element that is held in said housing and that defines a channel opening out into the tank, said striker element presenting a length greater than the length of the housing and projecting from the piston so that the fragile portion is broken by the striker element when the piston is in the second position.
The gas generator is configured to produce pressurizing gas that exerts pressure on the piston, which pressure is communicated by the piston for the material present in the tank. The outlet orifice is configured to allow the material to be delivered to the outside of the body as a result of the tank being pressurized by the gas generated in the pressurizing chamber.
The invention serves advantageously to provide a device that is reliable and of simple design, and that makes it possible, once the piston is in the second position at the end of dispensing the material, to depressurize the inside of the body automatically. Specifically, the design of the device of the invention merely requires a blind housing to be formed in the piston, which housing is closed beside the pressurizing chamber and open beside the tank and contains a striker element. When the piston is in the first position, the striker element projects from the piston into the tank. In addition, the striker element is of a length that is significant, being longer than the length of the housing. These characteristics of the striker element ensure that the fragile portion closing the housing is broken when the piston goes from the first position to the second position. Specifically, the gas generator is configured so that, when triggered, it causes the piston to move towards the end wall so as to move the striker element within the housing as a result of the projecting portion of the striker element impacting against the end wall. This movement of the striker element within the housing serves to break the fragile portion by impacting against it. When the fragile portion has broken, the pressurizing chamber is in communication with the tank and with the outlet orifice via the channel defined by the striker element so as to depressurize the inside of the body.
In an embodiment, when the piston is in the first position, the striker element has a first end facing the fragile portion and a second end projecting from the piston, the striker element presenting a cavity extending between its first and second ends and defining said channel.
Under such circumstances, when the piston goes from the first position to the second position, the impact of the second end with the end wall causes the striker element to move inside the housing so as to break the fragile portion by its first end impacting thereagainst. Once the fragile portion has broken, the pressurizing chamber is in communication with the tank and with the outlet orifice via the cavity defined by the striker element.
In an embodiment, the cavity is an inside cavity of the striker element.
In an embodiment, the striker element further comprises at least one first opening situated beside the first end and in communication with the inside cavity.
Such a characteristic serves advantageously to achieve effective depressurization in the event of the fragile portion shutting a portion of the inside cavity at the first end after breaking. Under such circumstances, depressurization takes place at least through the first opening.
In an embodiment, the striker element further comprises at least one second opening situated beside the second end and in communication with the inside cavity.
Such a characteristic further enhances discharging of the pressurized gas, in particular through the second opening.
In an embodiment, the striker element is also provided with a through slot extending between its first and second ends and in communication with the inside cavity.
Such a characteristic is advantageous insofar as the slot confers resilience to the striker element, making it easier to insert in the housing while fabricating the device. In addition, like the first and second openings described above, the through slot in communication with the inside cavity still further enhances depressurizing of the inside of the body.
In an embodiment, the striker element comprises a tubular wall surrounding the inside cavity, the first and second openings, when present, being through openings formed in the tubular wall.
In an embodiment, the cavity is defined by an internal spline present in the outer surface of the striker element.
In an embodiment, the striker element, when the piston is in the first position, comprises a first end facing the fragile portion and a second end projecting from the piston, said channel being defined by a volume situated between the striker element and a wall of the housing and extending between the first and second ends of the striker element.
Under such circumstances, when the piston goes from the first position to the second position, the impact of the second end against the end wall causes the striker element to move within the housing so as to break the fragile portion by impacting against it with the first end. Once the fragile portion has broken, the pressurizing chamber is in communication with the tank and with the outlet orifice via a volume defined by the striker element and by the wall of the housing.
In an embodiment, when the piston is in the first position, the housing comprises a first portion in which the striker element is held and situated beside the fragile portion, and a second portion situated beside the tank, which second portion is larger than the first portion.
The presence of the enlarged second portion of the housing still further enhances the discharging of the pressurized gas.
In an embodiment, the striker element has a portion of chamfered shape situated facing the fragile portion when the piston is in the first position.
Such a characteristic is advantageous since it makes it possible to break the fragile portion while tilting it so as to avoid it obstructing the channel once it has broken.
In an embodiment, the material for dispensing is in liquid form. In a variant, the material for dispensing is in the form of a foam or in powder form.
In an embodiment, the gas generator is a pyrotechnic gas generator. In a variant, the gas generator may be a tank of gas under pressure.
The present invention also provides a fire extinguisher formed by a device as described above in which the material for dispensing is an extinguishing agent. Nevertheless, the invention is not limited to using the above-described device as an extinguisher. In particular, in a variant, the above-described device could form a lubricator device in which the material for dispensing is a lubricant, such as lubricating oil.
Other characteristics and advantages of the invention appear from the following description of particular embodiments of the invention, given as non-limiting examples and with reference to the accompanying drawings, in which:
The device 100 has a body 110 of elongate shape. The body extends along an axis A. The body 110 is of axisymmetric shape about the axis A. In the example shown, the body 110 is cylindrical in shape. The body 110 of the device is closed at the first end by a first end wall 120 that has a pyrotechnic gas generator 130 fastened thereto, and at a second end it is closed by a second end wall 140. In a variant, it would be possible to use a tank of gas under pressure instead of the pyrotechnic gas generator. The axis A connects the first end wall 120 to the second end wall 140 and generally corresponds to the travel direction of the piston 150 in the body 110.
The piston 150 is present inside the body 110. When the piston 150 is in the first position, it defines inside the body 110 two chambers that are separated in sealed manner by said piston 150, one forming a pressurizing chamber 160 in which the gas generator 130 is present and the other forming a tank 170 storing the material that is to be delivered by the device 100. By way of example, the material that is to be delivered may be a liquid, a foam, or a powder material. The first end wall 120 defines the pressurizing chamber 160. The second end wall 140 defines the tank 170.
In the example shown, the pyrotechnic gas generator 130 comprises a pyrotechnic charge 131 that, on combustion, generates gas for pressurizing the pressurizing chamber 160. The gas generator 130 has an opening 132 centered on the axis A and including a flared portion through which the gas resulting from the combustion of the charge 131 can reach the pressurizing chamber 160. Such a pyrotechnic gas generator 130 is itself known, and is not described in greater detail herein.
The second end wall 140 of the device 100 is provided with an outlet orifice 141 that, in the example shown, is constituted by a through hole made in the second end wall 140. When the piston 150 is in the first position, as shown in
The piston 150 is of axisymmetric shape about the axis A and, by way of example, and as shown, it is cylindrical in shape. The piston 150 has a pressure application portion 151 extending transversely, e.g. perpendicularly, relative to the axis A. In the example shown, the pressure application portion 151 is in the shape of a disk. Furthermore, the piston 150 includes a skirt 152, which is cylindrical in shape in this example, extending from the portion 151 towards the first end wall 120. In a variant, it would be possible to use a piston without such a skirt. The portion 151 has a groove 153 that receives a gasket 154, e.g. of torroidal shape, that provides sealing between the pressurizing chamber 160 and the tank 170. The gasket 154 is positioned between the portion 151 and the body 110.
A housing 155 is provided in the piston 150 in the pressure application portion 151. When the piston 150 is in the first position, the housing 155 is a blind housing that is closed by a fragile portion 157 beside the pressurizing chamber 160 and that is open into the tank 170. When the piston 150 is in the first position, there is no communication between the pressurizing chamber 160 and the tank 170. In this first position, the chamber 160 and the tank 170 are separated in sealed manner by the piston 150, and in particular by the fragile portion 157 of the piston 150. A striker element 180 is held in the housing 155.
With reference to
The striker element 180 extends along a longitudinal axis corresponding to the axis A1 of the housing 155. The striker element 180 extends between a first end 180a facing the fragile portion 157 and a second end 180b projecting from the piston 150 and situated in the tank 170. The second end 180b projects from the piston 150 by a non-zero distance d measured between said second end 180b and the second face 151b. Unless mentioned to the contrary, the distance d is measured along the axis A1 of the housing 155. The striker element 180 is held tight in the first portion 155a of the housing 155. The striker element 180 exerts a clamping force that results from its contact with the wall of the housing 155. The clamping force exerted by the striker element 180 in the housing 155 serves to hold it in position while the piston 150 is in its first position. The striker element 180 may be inserted as a force fit in the housing 155. Because it is held in position, the striker element 180 does not break the fragile portion 157 before the generator 130 is actuated, e.g. as a result of the material shaking because of vibration or impacts to which the device 100 is subjected. Sealing between the tank 170 and the pressurizing chamber 160 is thus preserved before the device 100 is used.
In the configuration shown in
The striker element 180 used has the structure of a split tube with the structure that is shown in
With reference to
At the end of dispensing the material, when the piston reaches the second position the second end 180b of the striker element 180 that projects beyond the piston 150 comes into contact with the second end wall 140. As a result of this impact, the striker element 180 slides inside the housing and its first end 180a thus breaks the fragile portion 157 by impact. The force exerted by the second end wall 140 on the striker element 180 during the impact is strictly greater than the clamping force that holds the striker element 180 in the housing 155 so as to ensure that the striker element 180 is pushed into the housing.
After impact, the structure shown in
The striker element 280 shown in
The striker element 380 shown in
The striker element 480 shown in
The striker element 580 shown in
The striker element 680 shown in
In the example shown, the piston 450 defines clamping portions 452 that are to exert a clamping force on the striker element 980 so as to hold it in position in the housing 455 while the piston 450 is in the first position. As shown in
When the piston is in the second position and the first end 980a of the striker element 980 has broken the fragile portion 457, gas escapes along the path E via the channels 453 so as to be discharged to the outside of the device through the outlet orifice 341 in the second end wall 340 (
Number | Date | Country | Kind |
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1659163 | Sep 2016 | FR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/FR2017/052598 | 9/27/2017 | WO | 00 |