The invention relates to the dispensing of liquids and to a pipette with an elongate handle for gripping.
For dispensing liquids, there are used pipettes with a piston, by means of which liquid is absorbed in a pipette tip to be attached to a suction channel, and removed from said pipette tip. The pipette is provided with an elongate handle, by which the pipette can be gripped with a palm grip. The upper part of the handle is provided with a sideways extending finger support, offering a rest for the index finger, that improves the manual grip of the pipette. At the outer end, the finger support is slightly downwardly curved. Attempts for improving the tactile properties of pipettes have been realized by improving the handle design. In the prior art, there have also been used handles that are substantially universally thick, downwardly narrowing or roundish. From the Finnish patent publication FI 20012251, there also is known a pipette with a handle part that can be shaped by the user and even replaced with another one.
An invention according to the appended claims has now been made.
The pipette according to the invention is provided with a lower support at the lower part of the handle. It prevents the hand from sliding downwardly on the handle. Thus there is no need to grip the pipette as hard as with conventional pipettes, for example when a pipette tip is being placed at the tip. In this connection, the lower part of the handle refers to the part that is placed substantially in the area of the lower edge of the user's palm or the lowest finger.
The lower support is formed in the lower part of the handle, as a sideways extending protrusion, which protrusion is advantageously extended essentially radially with respect to the central axis of the pipette, but only in part of the cross-sectional area of the pipette at the location of the lower support. The lower support is advantageously extended for 3-8 mm from the surface level of the handle.
Preferably the top part of the handle also includes a finger support. The finger support is advantageously located on the same side of the handle as the lower support, most preferably so that the same plane, transversal to the handle, intersects both supports.
The lower support may be vertically movable and locked at a desired height within the limits of the motion tolerance. Thus the user may set the lower support at a location that is optimally suitable for his/her hand. The lower support may also be rotary with respect to the handle, and locked at a desired spot within the limits of the rotation tolerance. Thus the user may set the lower support at an optimal location with respect to the shape of his/her hand or his/her individual pipetting grip. In the center position, a rotary lower support is positioned at the same location as the finger support. From the center position, the lower support can be rotary in both directions, for example for 45-60 degrees.
When necessary, a pipette according to the invention may also be provided with a support section connecting the outer end of the finger support and the outer end of the lower support, so that in cross-section, the support structure of the pipette forms a closed shape.
The appended drawings belong to the written specification of the invention, and constitute an inseparable part of the detailed description of a few preferred embodiments of the invention, to be given below. In the drawings:
The pipette illustrated in the drawings includes a cylinder with a movable piston therein. These are fitted in an elongate body formed by a handle 1 and a tip part 2 placed at the lower end of the handle. At the end of the tip part, there is attached a pipette tip in which the liquid to be dispensed is sucked. As an extension of the piston, there is arranged a shaft 3 that is projected out of a hole provided at the upper end of the handle. The end of the shaft includes a button 4.
Pipettes are provided with a volume adjustment mechanism where the dispensing volume is set by winding the shaft 3 at the button 4. The set volume can be presented for example by means of numeral rings in a window arranged in the handle. This kind of mechanism is described for example in the publication WO 2005/050554. The button is preferably of a type having in the lengthwise direction of the shaft a lower position where the shaft is not rotated along with the button, and an upper position where the shaft is rotated along with the button. This is a way to try and prevent any accidental change in the volume settings. This kind of mechanism is described for example in the publication WO 2009/118456.
On top of the tip part 2, there is arranged a tip ejector sleeve 5. As an extension of the top part of said sleeve 5, at the side of the handle 1, there is arranged a spring loaded press button 6, which can be pressed down against the spring force, so that the sleeve pushes the pipette tip placed at the end of the tip part, thus detaching it. The force needed for detaching can be reduced by a lever mechanism, for example by means of a wheel moving in between the press button and the handle. This kind of mechanism is described for example in the publication WO 556939.
At the upper end of the handle 1, at the side thereof, there is provided a downwardly curved finger support 7, including a body part 8 and a contact element 9 located under the body part, to be rested against the finger. Generally the parts 8 and 9 of the finger support 7 are rigid elements, but when necessary, the contact element 9 to be placed against the finger can be realized as a softer and more elastic piece or section.
The lower part of the handle 1 is, at the side of the handle, provided with a lower support 10.1 (
In the pipette described in
In the pipette described in
In a pipette according to
In addition to the lower support 10.5 conforming to the shape illustrated in
Number | Date | Country | Kind |
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20106185 | Nov 2010 | FI | national |