Patent Description:
One application for such a sample testing device is a device wherein the sample collector receives a breath gas sample from a person. The testing device analyses the concentration of a given substance in the breath sample. In particular the device detects the presence of alcohol or a further mind-altering substance in the breath sample.

The breath gas sample flows from the person through the sample collector towards a gas sensor of the device. The gas sensor checks the received sample on the given substance.

Such breath sample testing devices are known from, e.g., <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, and <CIT>.

<CIT> shows a sample collector with a mouthpiece (Mundteil <NUM>) and a connecting part (Anschlussteil <NUM>) made as one piece of polypropylene.

One object of the invention is to provide a gas sample collector and a gas sample testing device with such a sample collector wherein the flow of breath gas through the sample collector is improved.

This object is solved by a sample collector according to claim <NUM> and by a gas sample testing device according to claim <NUM>. Preferred embodiments are specified in the depending claims. Preferred embodiments of the sample collector are also preferred embodiments of the gas sample testing device.

The sample collector according to the invention is arranged for receiving a breath gas sample, in particular a gas sample exhaled by a person towards the sample collector. The received breath gas sample is to be investigated.

The sample collector comprises an inflow part and an outflow part. The inflow part comprises an inflow opening. The outflow part comprises an outflow opening.

The sample collector provides a flow duct. This flow duct is arranged for guiding a gas sample from the inflow opening through the sample collector to the outflow opening. When a person ejects a breath gas sample, the inflow opening is directed towards the person. The gas sample flows through the flow duct.

The inflow part and the outflow part together form a housing. This housing defines the flow duct and surrounds the flow duct in a gas-tight manner. Thanks to the gas-tight housing a gas sample is guided from the inflow opening to the outflow opening and can leave the flow duct only through the outflow opening (or the inflow opening) but cannot leave the housing laterally.

A gas sample flows through the flow duct from the inflow opening to the outflow opening. The gas sample flows in a flow direction through the flow duct. In the following the terms "upstream" and "downstream" refer to this flow direction.

The inflow part tapers in a direction from the inflow opening towards the outflow opening. The outflow part tapers in a direction from the outflow opening towards the inflow opening. Therefore, the cross-sectional area of the flow duct first decreases and then increases again - seen in the flow direction from the inflow opening to the outflow opening.

According to the invention the inflow part tapers in a direction towards the outflow opening. In other words: The cross-sectional area of the inflow part decreases in the flow direction. Therefore, the gas sample is concentrated in the downstream direction towards the outlet of the inflow part which is opposite to the inflow opening. This feature increases the reliability of the sample collector in combination with a gas sensor arranged downstream of the sample collector by delivering a sufficient amount of gas to the gas sensor.

According to the invention the outflow part also tapers. With other words: The cross-sectional area of the outflow part increases in the flow direction. This feature reduces the risk of a jam of gas in the flow duct. In contrast the gas sample can expand in the outflow part.

The gas-tight housing for the flow duct provides a kind of nozzle or jet for the gas flowing from the from the inflow opening to the outflow opening. Thanks to this feature the flow duct better guides the gas. The risk that the flow of gas through the flow duct is perturbated is then reduced.

According to the invention the provided housing is gas-tight. Therefore, no breath gas can "escape laterally" from the flow duct. In contrast the gas which passes through the inflow opening into the flow duct can only leave this flow duct through the outflow opening (or the inflow opening).

Thanks to the gas-tight housing the risk is reduced that a turbulence in the flow duct occurs wherein this turbulence is caused by gas laterally or angularly "escaping" from or entering into the flow duct. In addition, the risk is excluded that air gets stuck or jams adjacent to a hole or aperture in the housing positioned between the inflow and the outflow openings. This risk is excluded because no holes are present in the housing.

Preferably the inflow part is mechanically connected with the outflow part. In one implementation the inflow part is rigidly connected with the outflow part. In a further implementation both parts are integrally formed, even monolithic, i.e. manufactured in one process step, e.g. by moulding. In an alternative implementation the inflow part is separably or releasably connected with the outflow part, i.e. the two parts can be disconnected from each other.

In one embodiment the inflow opening is circular with a diameter of at least <NUM>. Preferably the shape of the inflow opening, however, differs from an ideal circle. Such a shape better fits to a gas sample testing device which can be held in one hand. The maximal dimension of the inflow opening is at least <NUM>, preferably at least <NUM>. This feature enables a contactless input of a gas sample. In particular it is possible that a person blows towards the sample collector for inputting a breath gas sample. It is not necessary that the face of the person touches the sample collector. A contactless input is more hygienic than an input by using a mouthpiece. Nevertheless, a sufficient amount of a gas sample is received by the sample collector. Preferably the dimension of the inflow opening perpendicular to the direction of the maximal dimension is at least <NUM>.

Preferably the maximal dimension of the outflow opening is at least <NUM>, preferably at least <NUM>. This feature ensures that enough gas can flow out of the outflow part. The risk is reduced that a jam or backflow of gas occurs while the gas sample flows through the flow duct.

Preferably the length of the inflow part, i.e. the dimension in the flow direction, is between <NUM> and <NUM>.

The inflow part and / or the outflow part may taper linearly or in a parabolic or elliptic manner, e.g..

In one embodiment the inflow part comprises an inflow part transition aperture. The inflow part tapers in a direction from the inflow opening towards the inflow part transition aperture. The outflow part comprises an outflow part transition aperture. The outflow part tapers in a direction from the outflow opening towards the outflow part transition aperture. The two transition apertures may coincide. It is also possible that one transition aperture is larger than the other one. The larger opening may encircle the smaller one.

Preferably the maximal dimension of the inflow part transition aperture is no more than <NUM>, preferably no more than <NUM>. This feature enables a sufficient amount of compression of the gas sample flowing through the inflow opening. In addition, a sufficient amount is directed towards a gas sensor downstream of the sample collector. Preferably the maximal dimension of the outflow part transition aperture is also no more than <NUM>, preferably no more than <NUM>. This feature ensures that the outflow part fits to the inflow part. Preferably the maximal dimension of the inflow part transition aperture and the maximal dimension of the outflow part transition aperture are at least <NUM>. These features reduce the risk of a jam of gas in the flow duct.

Preferably the respective dimension of the inflow part transition aperture is between <NUM>% and <NUM>% of the inflow opening in the same direction perpendicular to the flow direction. The respective dimension of the outflow part transition aperture is between <NUM>% and <NUM>% of the outflow opening in the same direction. In one implementation the outflow part comprises an outflow part protrusion. This outflow part protrusion surrounds the outflow part transition aperture. A section of the inflow part engages into the outflow part transition aperture and is surrounded by the outflow part protrusion. In an alternative implementation the inflow part comprises an inflow part protrusion. This inflow part protrusion surrounds the inflow part transition aperture. A section of the outflow part engages into the inflow part transition aperture and is surrounded by the inflow part protrusion.

These implementations ensure a gas-tight housing even if the actual geometry of the inflow part and / or the outflow part differs slightly from a required geometry. Such a deviation may happen due to inevitable manufacturing tolerances. A double-wall mechanical connection between the inflow part and the outflow part is more stable than a mechanical connection just along an edge.

In one embodiment, the sample collector comprises a collector outlet which is preferably positioned downstream of the outflow part. The collector outlet comprises at least one outlet aperture, preferably several outlet apertures. The collector outlet guides a gas sample having passed the flow duct towards the or at least one outlet aperture. Preferably the collector outlet distributes the gas sample onto several outlet apertures of the collector outlet.

The sample collector comprises a collector casing. This collector casing surrounds the housing formed by the inflow part and the outflow part, preferably with a distance to the housing. The flow duct is therefore positioned in the interior of the casing. The housing guides the gas sample through the interior of the casing. Preferably the collector casing comprises at least one outlet positioned downstream of the inflow part. Due to the collector casing and the housing of the flow duct a dead space is provided between the casing and the housing. The inner surface of the collector casing and the outer surface of the housing form different walls of this dead space. The dead space can take the entire space between the inner surface of the collector casing and the outer surface of the housing or just a part of it. As the housing is gas-tight, no gas flowing through the flow duct can enter this dead space. It is possible that the collector casing surrounds the dead space in a gas-tight manner. It is also possible that a fluid connection between the dead space and the environment is established, e.g. through at least one opening in the collector casing.

Thanks to the collector casing and the housing the housing can be designed in view of aerodynamic requirements of the flow duct. It is possible that a user grips and therefore touches the collector casing. The collector casing can be designed to fulfil ergonomic and hygienic requirements. It is possible that the cross-sectional area of the collector casing remains constant in a flow direction from the inflow opening to the outflow opening or tapers along the entire length therebetween. Preferably some gripping elements are mounted at the outer surface of the collector casing. Thanks to the dead space the housing and the collector casing can be designed independently from each other and to fulfill specific requirements.

In another embodiment, the inflow part can releasably be inserted into the collector casing. After being inserted, the inflow part and the connected outflow part are kept and held by the collector casing. It is possible but not necessary that the outflow part is connected with the collector casing or with the optional collector outlet.

In yet another embodiment, the collector casing is mechanically connected with the collector outlet. This makes it easier to replace the housing for the flow duct, i.e. the inflow part and the connected outflow part. Preferably this mechanical connection is gas-tight and is a rigid connection. This increases the mechanical stability.

In one implementation the outflow part comprises a separator element and a supporting element. The separator element is arranged perpendicular or angular to the flow direction and to the collector casing and forms one wall of the dead space. Preferably the separator element entirely bridges the distance between the housing and the collector casing. The separator element therefore reduces the risk that the collector casing is mechanically pressed together. The separator element can be flat, i.e. extend in a plane, or curvilinear, i.e. curved towards the outflow opening.

The supporting element engages the inner side of the collector casing and / or touches the collector outlet. Preferably the supporting element is in a full-area contact with the inner side of the collector casing. This feature increases the mechanical stability and guides the outflow part when the outflow part is inserted into the collector casing. Preferably the supporting element comprises at least one aperture and / or recess which coincides or at least overlaps with an aperture of the collector outlet.

A preferred gas sample testing device comprises a sample collector according to the invention. In addition, the gas sample testing device comprises a base body. The sample collector is mechanically connected with the base body. The outflow opening of the sample collector points towards the base body. The sample collector is arranged to guide a received gas sample through the flow duct towards the base body. The base body comprises a gas sensor. The gas sensor is arranged to detect at least one substance in a received gas sample, preferably alcohol.

As the outflow opening points towards the base body, the gas sample can flow from the inflow opening through the flow duct and the outflow opening into the base body.

In another embodiment, the sample collector is connected with the base body such that at least a part of the gas sample can flow straight ahead from the inflow opening through the flow duct and the outflow opening into the base body and to the gas sensor without being deflected. Therefore, turbulences which may be caused by a deflection are avoided. In an alternative embodiment the sample collector is connected with the base body such that the gas sample is deflected when flowing from the sample collector into the base body. This alternative embodiment enables a user to carry the base body in an upright position which is sometimes more ergonomic. The user can blow into the sample collector when looking in a horizontal direction.

In another embodiment, the sample collector of the gas sample testing device comprises a collector outlet with at least one first outlet aperture and at least one second outlet aperture. The collector outlet is arranged downstream of the outflow part. The collector outlet guides a gas sample having passed the flow duct towards the outlet apertures and distributes the gas sample onto the first and second outlet apertures. The, or every, first outlet aperture directs a gas sample to the gas sensor. The, or every second outlet aperture directs a gas sample into the environment of the gas sample testing device, thereby circumventing the base body. This embodiment reduces the risk of a jam in the sample collector. The cross-section areas and the positions of the first and second outlet apertures serve as degrees of freedom for guiding the gas sample.

The collector casing may comprise one further outflow opening which is arranged downstream of the outflow part. This additional opening further reduces the risk of a jam.

In one application, the gas sample testing device is arranged for receiving a breath sample in a contactless manner from a person. The person exhales breath which is partly received by the sample collector and guided to the gas sensor. Preferably the gas sample testing device can be held in one hand.

In the following the invention is described with reference to preferred embodiments and with reference to the following figures:.

<FIG> shows a breath alcohol testing device <NUM> from two different viewing directions being perpendicular to each other. <FIG> further shows the area <NUM> surrounding the testing device <NUM>. This testing device <NUM> serves as the gas sample testing device according to one embodiment of the invention.

The testing device <NUM> has approximately the form of a cuboid with two larger surfaces and two smaller surfaces. <FIG> shows the testing device <NUM> in a side view; <FIG> shows it in a cross-sectional view in the plane A - A of <FIG>. The testing device <NUM> comprises a sample collector <NUM> and a base body <NUM>. The sample collector <NUM> can be removably connected with the base body <NUM>. Some fastening elements <NUM> fasten the sample collector <NUM> at the base body <NUM>, cf.

A person can blow a gas sample into the sample collector <NUM> without touching the sample collector <NUM>, i.e. in a contactless manner and therefore with a distance between the person's face and the testing device <NUM>. The flow direction in which the gas sample flows into the sample collector <NUM> is shown by an arrow FD.

The base body housing of the base body <NUM> surrounds a power supply unit <NUM> and a control unit <NUM>. Several gripping elements <NUM> at the base body <NUM> make it easier for a person to carry the base body <NUM> and thereby the testing device <NUM>. A display unit <NUM> in the base body housing can display measurement or test results in a human-perceptible form. A part of the injected gas sample is guided through the gas duct <NUM> to an alcohol sensor <NUM> in the interior of the base body <NUM>. This alcohol sensor <NUM> measures the alcohol concentration in the inserted gas sample. At least the measurement results of the alcohol sensor <NUM> enable an automatic decision whether or not the breath alcohol is above or below a given threshold. The alcohol sensor <NUM> can be an electro-chemical or an optical sensor, in particular an infrared sensor. Preferably the gas duct <NUM> guides the gas sample into a measuring chamber in the interior of the base body <NUM>.

<FIG> and <FIG> show the sample collector <NUM>. The sample collector <NUM> comprises an inflow part <NUM> with a guiding element <NUM>, an outflow part <NUM>, an optional collector outlet <NUM>, and a collector casing <NUM> with an outer wall <NUM>. The inflow part <NUM> is rigidly or releasably connected with the outflow part <NUM>. The two parts <NUM>, <NUM> together form the core sample collector. The core sample collector <NUM>, <NUM> can be inserted into the collector casing <NUM> and can be removed from the collector casing <NUM>. The collector casing <NUM> holds the core sample collector <NUM>, <NUM>, e.g. by means of a click-stop connection. <FIG> shows, in a perspective view, the sample collector <NUM> with the parts <NUM>, <NUM> not yet being inserted, <FIG> in a cross-sectional view the sample collector <NUM> with the parts <NUM>, <NUM> being inserted.

Several fastening elements <NUM> fasten the inserted inflow part <NUM> at the inner side of the outer wall <NUM> of the collector casing <NUM>. In one implementation every fastening element is a protrusion which engages a corresponding aperture in the outer wall <NUM>. Several gripping elements <NUM> make it easier for a person to grasp and hold the collector casing <NUM>.

In one embodiment described below the outflow part <NUM> between the guiding element <NUM> and the collector casing <NUM> implements an abrupt change in the cross section, cf. <FIG> and the first embodiment described below.

In one application, the core sample collector <NUM>, <NUM> is used for taking one sample and is afterwards replaced with a new one. It is also possible to reuse the core sample collector <NUM>, <NUM> several times, i.e. for several gas samples.

The elliptic inflow part <NUM> provides an elliptic inflow opening IO through which a gas sample can flow into the device <NUM>, cf. The inflow part <NUM> further provides an inflow part transition aperture <NUM> which is opposite to the inflow opening IO. The guiding element <NUM> tapers in a direction toward the inflow part transition aperture <NUM>. As can be seen, the inflow part <NUM> tapers in a parabolic manner, i.e. the reduction of the cross-sectional area decreases towards the inflow part transition aperture <NUM>. Preferably the guiding element <NUM> has the form of a cone or hopper.

The elliptic outflow part <NUM> provides an elliptic outflow opening OO through which a gas sample can flow towards the collector outlet <NUM>. The outflow part <NUM> further provides an outflow part transition aperture <NUM> which is opposite to the outflow opening OO. The core sample collector <NUM>, <NUM> of the embodiments therefore provides a kind of nozzle for guiding the gas sample along a flow duct.

The core sample collector <NUM>, <NUM> forms the housing for a main flow duct <NUM>. A gas sample from a person to be tested is injected through the inflow opening IO and flows through the main flow duct <NUM> towards the outflow opening OO and through the outflow opening OO into the collector outlet <NUM>. Gas can only "enter" into or "escape" from the core sample collector <NUM>, <NUM> through the inflow opening IO or through the outflow opening OO.

A gas sample can leave the core sample collector <NUM>, <NUM> into the collector outlet <NUM>. The gas sample can leave the collector outlet <NUM> and therefore the sample collector <NUM>.

Two small openings <NUM> are formed at the short side of the collector casing <NUM> and two large openings <NUM> at the longer side of the collector casing <NUM>. Several stiffeners form slotted apertures <NUM> in the large openings <NUM>. The gas duct <NUM> leads into the interior of the base body <NUM>.

The guiding element <NUM> provides the main flow duct <NUM> and prevents any large amount of gas flowing back towards the inlet opening IO of the inflow part <NUM>. A dead space <NUM> is formed between the core sample collector <NUM>, <NUM> and the collector casing <NUM>.

<FIG> show a first embodiment of the sample collector <NUM> wherein the outflow part <NUM> has a flat plane and flat top surface. <FIG> shows the core sample collector <NUM>, <NUM>. <FIG> shows the outflow part <NUM> of the first embodiment. <FIG> show a second embodiment of the sample collector <NUM> wherein the outflow part <NUM> has a curvilinear plane and curved top surface. <FIG> shows a third embodiment wherein the core sample collector <NUM>, <NUM> is integrally formed, i.e. made as one piece, and wherein the outflow part <NUM> also has a curvilinear plane.

The inflow part <NUM> has the following parts:.

The outflow part <NUM> has the following parts:.

In the third embodiment according to <FIG> the transition apertures <NUM> and <NUM> coincide. The inflow part <NUM> and the outflow part <NUM> form one unit. In <FIG> and <FIG> the optional collector casing <NUM> is not shown.

The optional collector casing <NUM> is rigidly connected with the collector outlet <NUM> and has the following parts:.

The collector outlet <NUM> comprises the central opening <NUM> and the lateral openings <NUM>. A rectangular aperture is formed between the collector casing <NUM> and the collector outlet <NUM>.

The guiding element <NUM> projects into the elliptic outflow part transition aperture <NUM>. The protrusion <NUM> surrounds the projecting section of the guiding element <NUM> in a manner that the connection between the guiding element <NUM> and the outflow part <NUM> is a gas-tight one. The connection between the inflow part <NUM> and the collector casing <NUM> provided by means of the fastening elements <NUM> is in one implementation also gas tight. The outer surface of the supporting element <NUM> contacts the inner surface of the collector casing <NUM> in a gas-tight manner.

Therefore, no gas which is blown or otherwise injected into the inflow part <NUM> and flow through the flow duct <NUM> can enter the dead space <NUM>. In contrast, the collector casing <NUM> on the outer side and the separator element <NUM> and the guiding element <NUM> on the inner side surround the dead space <NUM> in a gas-tight manner. In particular, the separator element <NUM> separates the dead space <NUM> from the outflow openings <NUM>. It is possible that a fluid connection between the dead space <NUM> and the environment <NUM> is established.

As can be seen from the exploded view, the inflow part <NUM>, the separator part <NUM> and the collector casing <NUM> can be manufactured separately, in particular by using different materials, and can be assembled later.

<FIG> shows the inflow opening IO and the inflow part transition aperture <NUM> wherein the viewing direction is parallel to the flow direction FD. The openings IO, <NUM> extend in the drawing plane of <FIG>. The following dimensions are shown:.

Preferred values for these parameters are:.

Preferably L1. IO is larger than L1. <NUM> and L2. IO is larger than L2. <NUM> such that gas is collected in the inflow part <NUM>. In a further preferred implementation L1. <NUM> is between <NUM>% and <NUM>% of L1. Preferably L2. <NUM> is between <NUM>% and <NUM>% of L2. IO may be above <NUM>, even above <NUM>.

It is also possible that the inflow opening IO has the form of a circle. The diameter of this circle is preferably between <NUM> and <NUM>. The inflow part transition aperture <NUM> may also be circular, preferably with a diameter between <NUM> and <NUM>. Preferably the diameter of the inflow part transition aperture <NUM> is between <NUM>% and <NUM>% of the diameter of the inflow opening IO.

Preferably the dimension of the outflow opening OO in a plane perpendicular to the flow direction FD is in every direction less than the inflow opening IO, in particular no more than <NUM>% less.

Claim 1:
Sample collector (<NUM>) for receiving a breath gas sample to be investigated,
wherein the sample collector (<NUM>) comprises an inflow part (<NUM>) with an inflow opening (IO), an outflow part (<NUM>) with an outflow opening (OO), and a collector casing (<NUM>),
wherein the sample collector (<NUM>) provides a flow duct (<NUM>) guiding a gas sample from the inflow opening (IO) to the outflow opening (OO),
wherein the inflow part (<NUM>) and the outflow part (<NUM>) together form a housing which surrounds the flow duct (<NUM>) in a gas-tight manner,
wherein the inflow part (<NUM>) tapers in a direction towards the outflow opening (OO),
wherein the outflow part (<NUM>) tapers in a direction towards the inflow opening (IO), and
wherein the collector casing (<NUM>) surrounds the housing formed by the inflow part (<NUM>) and the outflow part (<NUM>)
such that a dead space (<NUM>) is provided between the collector casing (<NUM>) and the housing.