Franking machine

Claim 2

A franking machine characterised by:- a secure module (12) comprising a secure housing (27) containing electronic circuits (13...22) for carrying out accounting functions and for maintaining account records relating to use of the franking machine in franking mail items; a communication port (23, 24) connected to the electronic circuits and extending to the exterior of said housing (27); and a printer (21) controlled by the electronic circuits to print a franking impression including a value of postage charge, said printer having printing elements (25) located exterior to the secure housing (27); and a non-secure base module (10) including feed means (48) to feed a mail item (55) past the printer (21) of the secure module (12) and input means (35) for input of a selected value of postage charge with which a mail item is to be franked and electronic control means (30) responsive to input of said selected value to input signals via the communication port (23, 24) of the secure module (12) to the electronic circuits (13...22) to cause said electronic circuits to carry out an accounting operation in respect of said selected value and to operate the printer (21) to print the franking impression including said selected value on a mail item fed by said feed means (48); and said secure module (12) being removably mounted on said non-secure base module (10) and said communication port (23, 24) being releasably electrically connected to said electronic control means (30).

Claim 3

A franking machine as claimed in claim 2 wherein the printer (21) comprises a thermal print head including a plurality of thermal print elements (25) carried by a substrate (26); print head driver circuits (22) carried by said substrate (26) and connected to said thermal print elements (25); and wherein the substrate (26) is mounted to the secure housing (27) such that said thermal print elements (25) are located exterior to said secure housing (27) and said print head driver circuits (22) are located within the secure housing (27).

Claim 4

A franking machine as claimed in any claim 2 or 3 including display means (36, 37) to display information to a user of the franking machine wherein said display means (36, 37) and the input means (35) are constructed as a module (11) mounted on the non-secure base unit (10).

Claim 5

A franking machine as claimed in claim 2, 3 or 4 wherein the electronic means (13) is operative in a recrediting operation in response to an input value of updating credit to increment said credit value by an amount equal to said input value of updating credit to an incremented value of credit and to store said incremented value of credit in the register and to operate said printer (21) to print a record of said incremented value of credit.

Claim 6

A franking machine as claimed in claim 5 wherein the electronic means (13) is operative in a recrediting operation to print a record of said value of credit stored in the register and of said incremented value of credit.

Claim 7

A franking machine charactersied by a secure postage meter (12); said postage meter (12) including a printer (21) for printing franking impressions on mail items (55); electronic means (13) operative in a franking operations to carry out accounting functions in respect of a credit value stored in a register (14, 15) of the postage meter and decrementing of said credit value by amounts of postage charge franked in franking impressions on mail items and to store the decremented value of credit in the register (14, 15) and to operate the printer (21) to print a franking impression indicating the amount of postage charge on a mail item (55) and said electronic means (13) being operative in a recrediting operation in response to an input value of updating credit to increment said credit value by an amount equal to said input value of updating credit to an incremented value of credit and to store said incremented value of credit in the register (14, 15) and to operate said printer (21) to print a record of said incremented value of credit.

Claim 8

A franking machine as claimed in claim 7 wherein the electronic means (13) is operative in a recrediting operation to print a record of said value of credit stored in the register (14, 15) and of said incremented value of credit.

Claim 9

A franking machine characterised by a secure postage meter (12); said postage meter (12) including a printer (21) for printing franking impressions on mail items (55); electronic means (13) operative in a franking operations to carry out accounting functions in respect of a credit value stored in a register (14, 15) of the postage meter and decrementing of said credit value by amounts of postage charge franked in franking impressions on mail items and to store the decremented value of credit in the register and to operate the printer (21) to print a franking impression indicating the amount of postage charge on a mail item (55); and non-secure display means (36, 37); a non-secure communication link (38, 33, 32, 30, 31) between said display means (36, 37) and said electronic means (13) in said secure postage meter (12); said electronic means (12) being operative in a recrediting operation in response to an input value of updating credit to increment said credit value by an amount equal to said input value of updating credit to an incremented value of credit and to store said incremented value of credit in the register (14, 15) and to operate said printer (21) to print a record of said incremented value of credit.

Claim 10

A franking machine as claimed in claim 9 wherein the electronic means (13) is operative in a recrediting operation to print a record of said value of credit stored in the register (14, 15) and of said incremented value of credit.