GB2188990A - A hand pump for operating an atomizer - Google Patents

Abstract

A hand pump for operating an atomizer, more particularly the atomizer of an inhaler, comprises a pump cylinder (7) and a piston guided therein. One end of the pump cylinder (7) is secured to a baseplate (2) so as to be pivotable around an axis (8) aligned transversely to the stroke of the piston. A lever (6) is pivoted at (5) to the baseplate (2) and the free end of the piston rod (9) projecting from the cylinder (7) is likewise secured to the pivoted lever (6). It is thus possible to use piston-cylinder units in which the swept volume has a large cross-section and the stroke can be kept correspondingly short, to avoid excessive dimensions. The increased power required for the pump is compensated by the power transmission resulting from the lever arm ratio through linking the piston-rod (9) to the pivoted lever (6). <IMAGE>

Description

SPECIFICATION A hand pump for operating an atomizer The invention relates to a hand pump for operating an atomizer, more particularly the atomizer of an inhaler, comprising a pump cylinder and a piston guided therein.

It is known for the atomizers of inhalers to be operated by electric pumps which generate a continuous stream of air flowing through the atomizer and atomizing the medicine to form an inhalable aerosol. The atomizing power is good, but the inhalers are expensive, relatively noisy because of the pump, and use large quantities of medicine, since inhalation occurs at intervals depending on breathing, whereas additional atomization may occur uselessly during expiration.

There are also simple and therefore inexpensive known inhalers in which the compressed air needed for atomization is produced by an elastic rubber, plastics or similar ball compressible by hand. These manual atomizers, however, have the disadvantage that the amount of compressed air which can be produced is relatively small. This directly affects the atomizing power and consequently the operation of an inhaler using the atomizer. Also, the continuously repeated compressing of the ball requires considerable manual force, which cannot be exerted over a prolonged period by every patient who wants to inhale and is frequently an excessive exertion for an invalid.

It has also been proposed to use a pistoncylinder unit for pumping instead of compressing a ball. The travel distance and the diameter have to be dimensioned to obtain adequate amounts of air at the right pressure.

Small cylinder and piston diameters enable high pressure to be obtained with little force.

However, the travel becomes very long if an adequate amount of air is to be produced by a single stroke. and consequently the hand pump becomes unacceptably large. If, on the other hand, the piston and cylinder diameter are increased, there will be a considerable increase in the amount of force which has to be exerted by an invalid by moving the piston in reciprocation, using a piston-rod fitted with a handle.

The invention is based on the problem of developing a hand pump for the atomizer of an inhaler so that it can be easily and reliably operated without being excessively large.

A hand pump solving this problem is characterised in that one end of the pump cylinder is secured to a baseplate pivotable around an axis extending transversely to the stroke of the piston, a pivoted lever is connected to the baseplate, and the free end of the piston rod projecting from the cylinder is secured to the pivoted lever.

In the hand pump according to the invention, the pivoted lever is swung up and down around its axis on the baseplate during pumping. The lever transmits the applied pivoting force to the piston-rod, the power being advantageously increased because of the leverarm ratio. The cylinder and piston can therefore be made correspondingly larger and the piston stroke can consequently be made relatively short. The hand pump can therefore have advantageously small dimensions but adequate pump power.

The baseplate enables the pump to be positioned in stable manner, with the further advantage that the baseplate and pivoted lever can be joined together and enclose the cylinder, piston and piston-rod between them. The pump can therefore be advantageously stowed away when not used.

The pump power can be further increased, in spite of the small dimensions and travel distances, if the cylinder has a rectangular, preferably square cross-section.

Rectangular, preferably square cylinder-piston unit cross-sections increase the swept volume and therefore the volume of compressed air can be generated by a given stroke as compared with a round cylinder and piston.

An inhaler atomizer supplied with compressed air e.g. via a hose connected to the hand pump, can thus be supplied with a sufficient quantity of air to ensure optimum atomization at high pressure, even if the strokes at the lever are short.

According to another feature of the hand pump, the baseplate has recesses open at one side for receiving and engaging bearing journals projecting from the cylinder. This greatly simplifies attaching the piston-cylinder unit to the baseplate. The bearing journals integrally moulded on the cylinder are simply inserted from above into the sockets. Similar sockets can be formed on the pivoted lever, so that the journals at the free end of the piston rod can likewise engage easily in the sockets in the pivoted lever.

According to a particularly advantageous feature, a clamp loaded by a spring is disposed on the baseplate and comprises a clamping jaw which engages under the edge of a table-top when a spring has been fully deflected by actuating the clamp.

By means of the clamping element, the baseplate of the hand pump, when placed on a table or the like, can be reliably secured to the table top and removed by means of a handle or the like when inhalation has finished.

Consequently a patient operating the hand pump with one hand does not need to hold it with the other hand. Instead, he can use his free hand for operating the inhaler.

The baseplate can comprise a box near the pivoted lever for advantageously stowing accessories such as a hose, coupling members, medicine bottles and the like. The box can be closed by a lid, either insertable or a hinged flap.

The baseplate, box and lever can easily be made of plastics by injection-moulding. Of course the piston-cylinder unit can also be made of plastics, with the advantage that the bearing journals and similar connecting members can be integrally moulded.

An embodiment of the invention showing additional inventive features is disclosed in the drawings, in which: Figure 1 is a side view of a hand pump installed on a table-top; Figure 2 is a front view of the pump and Figure 3 is a plan view of the pump.

Fig. 1 is a side view of a hand pump installed on a table-top 1. The pump has a baseplate 2 having raised box-like side portions 3 and 4. A pivoted lever 6 is connected to the baseplate and pivotable around a shaft or axis 5. Reference 7 denotes a cylinder secured to baseplate 2 and pivotable around an axis 8 aligned transversely to the travel of the piston guided in the cylinder. The piston rod 9 is connected to the pivoted lever by a locking joint 10, When lever 6 is moved up and down, piston rod 9 makes a stroke. As a result, compressed air is produced in cylinder 7 and can be discharged via a diagrammatically-indicated hose 11 and supplied e.g. to an atomizer (not shown).

A clamp 12 disposed at the front of the baseplate comprises a vertical guide 13 for a rod 14. A knob 15 is disposed at the top end of rod 14, and a clamping jaw 16 is disposed at the bottom end of rod 14. Knob 15 can be pressed from above, thus compressing a spring 17, and lifting jaw 16 from the underside of table-top 1. If knob 15 is simultaneously rotated, jaw 16 can be pivoted until it no longer extends underneath table-top 1 but, owing to the action of spring 17, is lowered into a downwardly open receiving pocket 18.

The pump can then be removed from the table-top. The jaw is shown in this position in Fig. 2.

Before the hand pump is started up, the clamping process is reversed, as soon as the hand pump has been placed on and near the edge of the table-top.

Fig. 2 is a front view of the hand pump in Fig. 1. Like components are denoted by like reference numbers. As Fig. 2 shows, the baseplate is wider than lever 6, and the lever has a handle opening 19 at its front free end.

As Fig. 2 also shows, the lever itself is constructed as a U-section member, having a U portion in which a bearing head 20 of pistonrod 9 is mounted.

The part of baseplate 1 which is wider than the pivoted lever can co-operate with the raised outer portion 4 to form a box 21 closable by a hinged lid 22.

Fig. 3 is a plan view of the hand pump in Figs. 1 and 2. Like parts are denoted by like reference numbers. As Fig. 3 shows, the hinged lid 22 also has a handle 23 and the lid is secured to the baseplate so as to be pivotable around the same axis 5 as lever 6.

Claims (8)

1. A hand pump for operating an atomizer, more particularly the atomizer of an inhaler, comprising a pump cylinder and a piston guided therein, characterised in that one end of the pump cylinder (7) is secured to a baseplate (2) pivotable around an axis (8) extending transversely to the stroke of the piston, a pivoted lever (6) is connected to the baseplate (2), and the free end of the piston rod (9) projecting from the cylinder (7) is secured to the pivoted lever (6).

2. A pump according to claim 1, characterised in that the cylinder (7) has a rectangular, preferably square cross-section.

3. A pump according to claim 1 or 2, characterised in that the baseplate (2) has recesses open at one side for receiving and engaging bearing journals projecting from the cylinder (7).

4. A pump according to any of claims 1 to 3, characterised in that the pivoted lever (6) has recesses for engaging the journals disposed at the free end of the piston-rod.

5. A pump according to any of the preceding claims, characterised in that a clamp (12) loaded by a spring (17) is disposed on the baseplate (2) and comprises a clamping jaw which engages under the edge of a table-top (1) when a spring has been fully deflected by actuating the clamp.

6. A pump according to any of the preceding claims, characterised in that the baseplate (2) comprises a box (21).

7. A pump according to any of claims 1 to 6, characterised in that the baseplate (2), Box (21) and lever (6) are injection-moulded parts made of plastics.

8. A pump substantially as herein described with reference to the accompanying drawings.