Patent Application
20160228871
The present invention relates to a sample ampoule for calorimetric measurements comprising a vial, a lid and a sealing member, where the vial, lid and sealing member are adapted to form a hermetically sealed sample ampoule.
Using hermetically sealed sample ampoules is a prerequisite for correct measurement of thermal flow in isothermal calorimetry. Any leakage of gas and/or vapor will decrease the accuracy of the measurement.
Sealing of sample ampoules typically involves some combination of a gasket or O-ring seal with a tightening solution e.g. threaded lid or cap.
The prerequisite of sample ampoule absolute air and moisture tightness demands a closing mechanism with high precision able to withstand multiple opening and closing cycles with retained sealing properties and high reproducibility.
A normal solution for isothermal calorimetry includes O-ring seal and some locking device e.g. threaded cap. Tightening of the cap leads to compression of the O-ring and buildup of stored energy. The stored energy is subsequently released and interferes with measurement accuracy. Energy buildup and release must be controlled to achieve measurement reproducibility.
Also wear on the threads introduced by friction can affect the stability and accuracy of the measurement.
With the purpose of solving one or more of the above mentioned problems, and from the standpoint of a sample ampoule for calorimetric measurements comprising a vial, a lid and a sealing member, where the vial, lid and sealing member are adapted to form a hermetically sealed sample ampoule, the present invention teaches that the vial has a first contact surface and the lid has a second contact surface, where the first and second contact surfaces are in contact with each other in a sealed position of the ampoule. With the purpose of reducing the friction between the first and second contact surface, and thus reducing wear of the surfaces and the buildup of energy while closing the ampoule, it is proposed that the vial and lid are formed out of materials with different tensile strength.
Also for the reason of reducing friction between the first and second surfaces it is proposed that the first or second contact surface is coated with a low friction surface coating.
In the selection of materials with different strength it is proposed that the lid material is a high tensile material with strength exceeding the vial material, in which case the first contact surface may be coated with a low friction surface coating.
However, it is also possible that the vial material is a high tensile material with strength exceeding the lid material, in which case the second contact surface may be coated with a low friction surface coating.
It is proposed that the low friction surface coating can be made out of titanium nitride, which for instance could be the BALINIT® A of Oerlicon Balzers.
It is also proposed that the sealing member can be a gasket or an O-ring.
With an embodiment where the first contact surface and the second contact surface are threaded to form a closing mechanism and locking device when interacting with each other, it is proposed that the ampoule is adapted to an interaction with a means for applying a fixed torque to the lid when screwed to the vial.
The advantages of an inventive sample ampoule are that the friction of the thread will be reduced as well as the long-term wear of the thread will decrease due to the selection of materials with different strength and the coating.
The adaption to a use of a controlled torque release for tightening of the lid on the sample vial will provide a fixed and reproducible torque for the tightening which will increase in reproducibility of the measurements of the samples.
The fixed and reproducible torque for the tightening of the lid in combination with the reduced friction between the lid and the vial will also result in that more and a consistent amount of the energy applied will be transferred to the sealing member compacting and not be lost in the friction in the thread thus increasing reproducibility of the force applied to the sealing member.
A sample ampoule according to the present invention will now be described in detail with reference to the accompanying drawings, in which:
The present invention will now be described with reference to
The invention teaches that the vial 11 and lid 12 are formed out of materials 11′, 12′ with different tensile strength.
It is proposed that the first or second contact surface 11a, 12a is coated with a low friction surface coating (not shown).
According to one proposed embodiment the lid material 12′ is a high tensile material with strength exceeding the vial material 11′, in which case it is proposed that the first contact surface 11a may be coated with a low friction surface coating.
It is also possible that the vial material 11′ is a high tensile material with strength exceeding the lid material 12′, in which case the second contact surface 12a may be coated with a low friction surface coating.
One proposed embodiment teaches that the low friction surface coating is made out of titanium nitride, such as be the BALINI® A of Oerlicon Balzers.
The sealing member 13 can be a gasket or, as indicated in
A closing mechanism and a locking device can be formed in different ways, and one proposed way, as shown in the figures, is that the first contact surface 11 a and the second contact surface 12a are threaded thereby enabling the closing and locking of the ampoule 1 when interacting with each other.
It is proposed that the ampoule 1 is adapted to an interaction with a means for applying a fixed torque to the lid 12 when screwed to the vial 11. This can be done in many different ways,
It will be understood that the invention is not restricted to the aforedescribed and illustrated exemplifying embodiments thereof and that modifications can be made within the scope of the invention as defined by the accompanying Claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1351135-7 | Sep 2013 | SE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/SE2014/050950 | 8/20/2014 | WO | 00 |
