Reservoir module comprising a piston rod

A disposable reservoir module for a product dispensing apparatus, said reservoir module comprising:

• a) a front casing section, which comprises a reservoir for a product which can be delivered, a blocking means and a connecting means for establishing a detachable connection to a dosing and activating module of the product dispensing apparatus, said detachable connection enabling the disposable reservoir module to be removed from the dosing and activating module and to be replaced with another said disposable reservoir, whereby said dosing and activating module may be used with more than one said reservoir module one after the other;
• b) a piston accommodated in said reservoir such that it can be moved in an advancing direction toward a reservoir outlet to deliver product;
• c) a dosage setting member accommodated by said front casing section such that it can be moved to perform a dosing movement and a delivery movement;
• d) and a piston rod connected to said dosage setting member and held by the front casing section to contact the piston and shift in the advancing direction such that:
• i) said dosing movement does not cause said piston rod to move in the advancing direction;
• and
• ii) said delivery movement causes said piston rod to move jointly with said dosage setting member in the advancing direction;
• e) wherein the piston rod comprises a returning blocking means for blocking engagement with said blocking means, said blocking engagement preventing the piston rod from moving counter to the advancing direction relative to the front casing section.

A dispensing apparatus comprising:

• a disposable reservoir module comprising a front casing section, a block, a first connector, a piston, and a piston rod moveable in and against a dispensing movement and including a return block engageable with the block, wherein engagement between the block and the return block prevents the piston rod from moving against the dispensing movement;
• a reusable dosing module comprising a rear casing section including a second connector engageable with the first connector to form a detachable connection between the reservoir module and the dosing module;
• and
• a dose setting member engageable with the piston rod such that it is moveable together with and in the same direction as the piston rod during the dispensing movement and is moveable relative to the piston rod against the dispensing movement during the dose setting movement, whereby with each dispensing movement the piston rod advances into the disposable reservoir module and the piston rod and dose setting member are disposable with the disposable reservoir module.

A product dispensing apparatus, comprising:

• a front half comprising a front casing section, a reservoir part, a piston accommodated in the reservoir part and a front mechanism carried by the front half, the front mechanism comprising a first latching element, a mechanism holder, a piston rod held by the mechanism holder and a dosage setting member accommodated in the mechanism holder;
• and
• a rear half comprising a rear casing section and a rear mechanism carried by the rear half comprising a second latching element, a dosing and activating element, and a dosing and slaving means inserted into the dosing and activating element;
• the product dispensing apparatus further comprising:
• a) a first coupling for joining the front and rear halves, the first coupling comprising:
• i) at least one axial guide formed on the front casing section and at least one engagement element formed on the rear casing section, which forms a linear guide when establishing a connection between the casing sections, such that the casing sections are slid onto each other as far as a connecting end position, such that they cannot rotate relative to each other about a rotational axis;
• and
• ii) a latching block coupled to the dosing and activating element, the latching block comprising a blocking element and a longitudinally sliding recess, wherein the blocking element prevents detachment of the second latching element from the first latching element during delivery of the product until the drive element reaches a releasing position wherein the longitudinally sliding recess is aligned to permit movement of the second latching element into the longitudinally sliding recess to enable detachment of the second latching element from the first latching element;
• b) a second coupling for operably joining the mechanisms carried by the front and rear halves, the second coupling comprising:
• i) the dosing and activating element carried by the rear section such that it can move in and counter to an advancing direction and which acts on the piston rod during a delivery movement in the advancing direction, to move the piston in the advancing direction;
• ii) the piston rod comprising a connecting section for coupling to the dosing and activating element, wherein the connecting section is formed such that the coupling between the piston rod and the dosing and activating element allows the dosing and activating element and the piston rod to shift relative to each other along the longitudinal axis of the piston rod and prevents the dosing and activating element and the piston rod from rotating relative to each other about the longitudinal axis of the piston rod and wherein the connecting section is formed as a linear guide for the dosing slaving means;
• and
• iii) the dosage setting member which is accommodated by the front casing section such that the dosage setting member is moved in the advancing direction by the dosing and activating element during the delivery movement and which engages with the piston rod such that it is moved jointly with the piston rod in the advancing direction and is moved relative to the piston rod counter to the advancing direction, and wherein the front casing section forms a guide for the dosage setting member.