Surgery – Liquid medicament atomizer or sprayer – Pre-pressurized container holding medicament
Reexamination Certificate
1998-02-27
2001-01-09
Lewis, Aaron J. (Department: 3761)
Surgery
Liquid medicament atomizer or sprayer
Pre-pressurized container holding medicament
C128S200140
Reexamination Certificate
active
06170482
ABSTRACT:
This invention relates to an inhalation apparatus for dispensing substances for inhalation and, in particular, but not exclusively, for dispensing medicinal products in aerosol form from a pressurised dispensing container.
In known metered dose inhalers, the aerosol stream from a pressurised dispensing container is fired towards a patient or user of the inhaler into an airflow travelling in the same direction. In known devices, a user inhales through a mouthpiece of the inhaler and creates an airflow through the container from air inlet holes which are generally at a part of the inhaler well spaced from the mouthpiece. The medicament is then released into this airflow at a point between the air inlet holes and the mouthpiece so that it is travelling in the same direction as the airflow. Typically, in such devices, there is no restriction in the airflow between the air inlet holes and the mouthpiece. Because of this, a substantial airflow may be created by a user of the device and, because the medicament is fired into the airflow in the same direction as the airflow, the effect is that particles of medicament can obtain quite substantial velocities. As inhalers of this type are normally designed to be as small as practical for the convenience of users, the distance between the point at which the medicament is fired into the airflow and the patient's mouth is usually quite small, so that there is little distance to reduce the inertia of particles of medicament with the result that the particles may impact in the oro-pharynx of a user with quite high velocity. This can be a problem with some medicaments. It is also known to provide a sensor in an inhalation apparatus to detect inhalation by the user in order to synchronise with inhalation the release into the inhaled airflow of the substance to be inhaled. It is, for example, important in the administration of aerosol products for the relief of asthma that the timing of the dispensing operation should be carefully controlled to ensure maximum deposition of substance in the user's lungs.
It is known from GB-A-226 6466 to provide an electrically operated dispensing means responsive to a signal generated by a sensor which is responsive to a flow of air through a passageway. A disadvantage of this solution is that the apparatus is expensive.
In an effort to overcome these problems, devices have been produced in which the medicament is fired into a holding volume which allows the velocity of the medicament to be reduced and also allows some evaporation to occur.
However, these devices with a holding volume tend to be of significantly larger size than the standard metered dose inhalers and, therefore, less convenient and attractive to users.
One solution proposed in GB-A-2279879 uses a reverse flow. In this inhaler, the air inlets are provided at a location axially between the air outlet of the duct means connecting an outlet of the container with the mouthpiece and the mouthpiece, and a passage is provided connecting the inlets to a location adjacent to the outlet of the duct means. Thus, when a user inhales through the mouthpiece, an airflow is created from the inlet means to the mouthpiece, the airflow having a component directed away from the mouthpiece towards the outlet of the duct means.
An object of the present invention is to provide an inhaler which allows delivery of medicament to the user at reduced velocity without significantly increasing the size of the inhaler. Additionally, another object is to provide an inhaler which coordinates the discharge of the medicament with the inhalation cycle of the user in order to optimise the deposition of the medicament in the user's lungs.
The present invention therefore provides a housing having a portion adapted to receive a pressurised dispensing container of a product and a mouthpiece, said apparatus further comprising duct means communicating with the container, said duct means having an outlet defining the direction of flow of the product towards the mouthpiece section, air inlet valve means comprising at least one air inlet for allowing air into the housing and an airflow controller biased to seal said air inlet, said airflow controller being manually movable to unseal the air inlet to allow air to flow into the housing when a user applies suction to the mouthpiece, passage means being provided to direct the airflow to a location adjacent the outlet of the duct means, the positioning of the passage means relative to the duct means outlet and the mouthpiece being such that a component of the initial air flow direction opposes the product flow before being directed towards the mouthpiece.
An advantage of the present inhaler is that medicament is delivered to a user in the action of inhaling, allowing a greater proportion of the medicament to be deposited in the user's lungs. Also the dispensed medicament is slowed and mixed by the reverse flow of air away from the mouthpiece, towards the opening of the duct means, and the vortex created, decreasing the chance of damage to the user's throat and increasing the amount of medicament deposited in the user's lungs.
Preferably the housing comprises a partition separating the housing into an upper cylindrical portion for receiving a dispensing container and a lower portion for receiving the airflow controller, wherein the air inlet is located in the partition and the airflow controller has a movable actuator for sealing the air inlet.
Preferably the airflow controller comprises a spring biasing the actuator into contact with the partition.
Preferably the actuator has an extended member which projects into the upper portion of the housing and which, in use, is contacted by the container.
Preferably the passage means comprises a passage formed between an extension of the mouth piece and a support means surrounding the duct means configured to direct the flow of air there through with a component of its velocity towards the duct outlet.
REFERENCES:
patent: 4592348 (1986-06-01), Waters, IV et al.
patent: 4852561 (1989-08-01), Sperry
patent: 4940051 (1990-07-01), Lankinen
patent: 5040527 (1991-08-01), Larson et al.
patent: 5178138 (1993-01-01), Walstrom et al.
patent: 5447150 (1995-09-01), Bacon
patent: 5598836 (1997-02-01), Larson et al.
patent: 6082355 (2000-07-01), Howlett
patent: 0147028 (1985-07-01), None
patent: 1021739 (1966-03-01), None
patent: 2061116 (1981-05-01), None
patent: 2104393 (1982-08-01), None
patent: 2279879 (1995-01-01), None
Bespak plc
Lewis Aaron J.
Mitchell Teena
Smith , Gambrell & Russell, LLP
LandOfFree
Inhalation apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Inhalation apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Inhalation apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2482223