Electric heating – Heating devices – Tool or instrument
Reexamination Certificate
2001-03-29
2001-11-27
Hoang, Tu Ba (Department: 3742)
Electric heating
Heating devices
Tool or instrument
C219S201000, C219S227000, C219S233000, C606S219000
Reexamination Certificate
active
06323461
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention generally relates to shape memory clamps which can be closed using a device for heating and closing heat-retractable shape memory clamps, and which are particularly well suited for use in surgery applications.
More particularly, the present invention relates to shape memory clamps which can be closed using a device for heating and closing nickel/titanium alloy clamps, including clamps of the type referred to in the industry as “hot staples”. Shape memory clamps are initially open at ambient temperature, for purposes of placement. A quantity of heat is then provided to close the positioned clamp and thus provide tissue support.
In practice, the ergonomic and economic standardization of surgical constraints requires such clamps to be manufactured to extremely restrictive specifications.
In this context, it is important for the device to be able to close all types of heated clamps, whether they be monocortical or bicortical, bipode or quadripode clamps, and irrespective of their section. It is also important for the device to include a reliable and effective safety system to prevent accidental bone necroses due to the heat applied by the device. It is also important for the device to have a heating cord that can be sterilized in an autoclave or disinfected in a bath.
SUMMARY OF THE INVENTION
Such goals are achieved in accordance with the present invention by providing shape memory clamps, of the type generally know as “hot staples”, which can be closed using a device for heating and closing heat-retractable shape memory clamps used in surgery applications and which is generally comprised of a unit which contains an electronic power and control circuit and a heating unit.
The electronic power and control circuit is preferably comprised of a current supply, a controller and an adjustment circuit which combine to deliver several predetermined quantities of heat, each corresponding to a given size of clamp.
Primarily for purposes of safety, the adjustment circuit is configured (calculated) so that the amount of heat delivered to a given clamp does not cause the temperature of the clamp to exceed a maximum value, such as 55° C. Also for purposes of safety, the electronic circuit further includes an automatic cut-out circuit for discontinuing the application of heating current at the end of a predetermined maximum time, such as 5 seconds, and a sound signalling circuit for emitting a first sound as a signal during the application of heat to the clamp (the heating time) and a second sound which differs from the first sound as a signal that the maximum heating time has been exceeded.
The heating unit is preferably constructed as a sterilizable unit. One end of the heating unit has a plug which can be plugged into a corresponding outlet of the device and the other end of the heating unit has a sleeve which includes a pair of heating electrodes and a control switch. The sterilizable unit is fully sealed and the several elements which comprise the sterilizable unit are selected to withstand the conditions of an autoclave. In its preferred embodiment, the control switch is provided with pressure-sensitive contacts.
Any of a variety of heat-retractable shape memory clamps of the type generally referred to in the industry as “hot staples” may be employed with the above-described heating device. Preferred staples will advantageously comprise a quantity of a nickel-titanium alloy which varies between 0.8 g and 2.8 g. The electronic power and control circuit of the device includes a selection knob having settings which are matched to the type and size of the clamp being used so that the prongs of the clamp are closed both automatically and without the danger of accidental bone necroses. For example, a variety of monocortical and bicortical bipodes can be employed, with the selection knob set at one of a number of relatively low power settings (e.g., the settings 1 to 5, of 10). A variety of epiphysial bipodes and quadripodes can also be employed, with the selection knob set at one of a number of relatively high power settings (e.g., the settings 5 to 10, of 10).
The present invention shall be more readily understood from the following description, with reference to the accompanying drawings.
REFERENCES:
patent: 3174851 (1965-03-01), Buehler et al.
patent: 3868956 (1975-03-01), Alfidi et al.
patent: 4485816 (1984-12-01), Krumme
patent: 4550870 (1985-11-01), Krumme et al.
patent: 4665906 (1987-05-01), Jervis
patent: 4890613 (1990-01-01), Golden et al.
patent: 5067957 (1991-11-01), Jervis
patent: 5190546 (1993-03-01), Jervis
patent: 5597378 (1997-01-01), Jervis
patent: 2747911 (1997-10-01), None
patent: WO9616603 (1996-06-01), None
Cohen Gary M.
Hoang Tu Ba
M.B.A., S.A.
LandOfFree
Clamps with shape memory does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Clamps with shape memory, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Clamps with shape memory will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2571215