Abstract: The invention relates to a method and a magnetoencephalography (MEG) measurement device. In the method there is determined the ending of a scheduled inactivity period of the MEG device. At the ending of the inactivity period a cryocooler of the MEG device is switched off. Helium is allowed to boil in the Dewar vessel of the MEG device when the MEG device is active and used to perform patient measurements. The boiled helium is collected via a compressor to an external storage tank. When a new inactivity period for the MEG device commences, the cryocooler is started anew and helium is let from the external storage tank in-to the Dewar vessel, where it is re-liquefied by the cryocooler. The compressor may be switched off when the cryocooler is switched on.

Abstract: The invention relates to a method and a magnetoencephalography (MEG) measurement device. In the method there is determined the ending of a scheduled inactivity period of the MEG device. At the ending of the inactivity period a cryocooler of the MEG device is switched off. Helium is allowed to boil in the Dewar vessel of the MEG device when the MEG device is active and used to perform patient measurements. The boiled helium is collected via a compressor to an external storage tank. When a new inactivity period for the MEG device commences, the cryocooler is started anew and helium is let from the external storage tank in-to the Dewar vessel, where it is re-liquefied by the cryocooler. The compressor may be switched off when the cryocooler is switched on.

Abstract: The present invention discloses a joint structure between the wall elements of a light-weight magnetically shielded room. In the joint structure, the end of the aluminum plate of the element is stepped and its surface roughened. In addition to this, the aluminum plate is coated, for example, with tin to improve the electrical contact. The joint includes ? metal plates which are used to make a magnetic contact between the ? metal plates of the elements. The compression force achieved by means of bolts is transmitted to the joint by means of an aluminum moulding. The non-continuous compression force is balanced over the entire joint area by using presser rubbers. The joint structure is protected by means of supporting profiles which are used to electrically couple the thinner aluminum plate of the sandwich type wall element to the thinner aluminum plate of an adjacent element. The thinner aluminum plate and the supporting profile can also be coated, for example, with tin to improve the contact.

Abstract: The present invention discloses a joint structure between the wall elements of a light-weight magnetically shielded room. In the joint structure, the end of the aluminum plate of the element is stepped and its surface roughened. In addition to this, the aluminum plate is coated, for example, with tin to improve the electrical contact. The joint includes ? metal plates which are used to make a magnetic contact between the ? metal plates of the elements. The compression force achieved by means of bolts is transmitted to the joint by means of an aluminum moulding. The non-continuous compression force is balanced over the entire joint area by using presser rubbers. The joint structure is protected by means of supporting profiles which are used to electrically couple the thinner aluminum plate of the sandwich type wall element to the thinner aluminum plate of an adjacent element. The thinner aluminum plate and the supporting profile can also be coated, for example, with tin to improve the contact.