Inhaler

Abstract

A breath actuated inhaler for delivering medicament by inhalation, comprising a housing having a mouthpiece and defining an air flow path extending from the mouthpiece through the housing; the housing holding a replaceable canister of medicament actuatable to deliver a dose of medicament into the air flow path, wherein the housing defines an opening in the air flow path and the opening is closed by a closure element connected to and replaceable with the canister. The closure element acts as a safety feature because it is only closed when the inhaler is used with a canister to which a closure element is connected the closure element carries an indication of the type of medicament in the canister to allow the user to recognise the type of medicament. A plurality of inhalers may be provided in which each given inhaler has an opening with a different shape and has a closure element with a shape which conforms with the opening of the given inhaler but which does not conform with the openings of the other inhalers.

1 . An inhaler for delivering medicament by inhalation, comprising: 
 a housing having a mouthpiece and defining an air flow path extending from the mouthpiece through the housing;    the housing holding a replaceable canister of medicament actuatable to deliver a dose of medicament into the air flow path,    wherein the housing defines an opening in the air flow path and the opening is closed by a closure element connected to and replaceable with the canister.    
     
     
         2 . An inhaler according to any one of the preceding claims, wherein the closure element carries an indication of the type of medicament in the canister.  
     
     
         3 . An inhaler according to  claim 2 , wherein the indication is a tactile surface.  
     
     
         4 . An inhaler according to  claim 1 ,  2  or  3 , wherein the opening is defined in the outer surface of the housing.  
     
     
         5 . An inhaler according to  claim 4 , wherein the opening is provided adjacent the mouthpiece.  
     
     
         6 . An inhaler according to any one of the preceding claims, wherein the housing has two coupled portions which are separable to allow insertion of a canister and which are shaped to define the opening between the two portions when coupled together.  
     
     
         7 . An inhaler according to any one of the preceding claims, wherein the housing has outer walls defining a space which constitutes the air flow path.  
     
     
         8 . An inhaler according to any one of the preceding claims, further comprising an actuation mechanism arranged to be operated to actuate the canister by a flow through the air flow path, the opening being arranged, when open, to vent the flow sufficiently to prevent operation of the actuation mechanism.  
     
     
         9 . An inhaler according to  claim 8 , wherein the actuation mechanism includes a trigger disposed in the air flow path responsive to the flow to cause operation of the actuation mechanism.  
     
     
         10 . An inhaler according to  claim 9 , wherein the actuation mechanism further comprises a pre-loading mechanism arranged to store a loading force for actuation of the canister, the trigger being arranged to release the stored force.  
     
     
         11 . An inhaler according to  claim 9  or  10 , wherein the trigger is a vane arranged to be physically moved by a flow through the air flow path.  
     
     
         12 . An inhaler according to any one of  claims 9  to  11 , wherein the opening is disposed in the air flow path between the trigger and the mouthpiece.  
     
     
         13 . An inhaler according to any one of  claims 8  to  12 , wherein the housing defines an inlet opening for the air flow path having a smaller opening area than the opening.  
     
     
         14 . An inhaler according to any one of the preceding claims, wherein the canister and the closure element are connected by a connector which is arranged to prevent reconnection after separation of the canister and the closure element.  
     
     
         15 . An inhaler according to  claim 14 , wherein the connector is formed with a weak portion arranged to be broken in preference to the remainder of the connector on application of a force to separate the canister and the closure element.  
     
     
         16 . An inhaler according to any one of the preceding clams, wherein the closure element is connected to a collar fitted around a necked portion of the canister as a connector between the canister and the closure element.  
     
     
         17 . A plurality of inhalers each according to any one of the preceding claims, wherein each given inhaler has a opening with a different shape and has a closure element with a shape which conforms with the opening of the given inhaler but which does not conform with the opening of the other inhalers.  
     
     
         18 . A plurality of inhalers according to  claim 17 , wherein the shapes of the opening and the closure element of a given inhaler prevent fitting of the closure element in an inhaler other than the given inhaler.  
     
     
         19 . A plurality of inhalers according to  claim 17  or  18 , wherein the inhalers further comprise an actuation mechanism arranged to be operated to actuate the canister by a flow through the air flow path and the shape of the closure element of a given inhaler is such that when the closure element fitting in inhaler other than the given inhaler leaves open the opening of the other inhaler sufficiently open to prevent operation of the actuation mechanism of the other inhaler.  
     
     
         20 . A plurality of inhalers each according to any one of  claims 1  to  15 , wherein the canisters held in different inhalers store different types of medicaments and the closure elements of the different inhalers carry respective different indications of the types of medicament in the canisters to which they are connected.  
     
     
         21 . An inhaler for delivery of a medicament by inhalation, comprising a housing having a mouthpiece and defining an air flow path extending from the mouthpiece through the housing, the housing being arranged to hold a replaceable canister of medicament actuatable to deliver a dose of medicament into the air flow path, wherein the housing defines an opening in the air flow path arranged to be closed by a closure element connected to the canister.  
     
     
         22 . A canister adapted for use in an inhaler according to  claim 21  having connected thereto a closure element for closing the opening in the airflow path defined in the housing of the inhaler.  
     
     
         23 . A canister inhaler according to  claim 22 , wherein the canister and the closure element are connected by a connector which is arranged to prevent reconnection after separation of the canister and the closure element.  
     
     
         24 . A canister according to  claim 23 , wherein the connector is formed with a weak portion arranged to be broken in preference to the remainder of the connector on application of a force to separate the canister and the closure element.  
     
     
         25 . A canister according to any one of  claims 21  to  24 , wherein the closure element is connected to a collar fitted around a necked portion of the canister as a connector between the canister and the closure element.