Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
307 words
A pipetting device comprising: a housing having a top end, an actuating element, which protrudes from said top end and is depressible against spring action, a piston, which is axially connected to the actuating element, a cylinder, which is disposed in said housing and contains said piston, which is movable in said cylinder to move an air volume, a tubular pipette connector, which is adapted to be slidably fitted into a pipette tip, which connector and tip are open at both ends, means which connect said cylinder and said pipette connector and establish a fluid communication between the interior of said cylinder and the interior of said pipette connector, means by which said actuating element is rotatably mounted in said housing, and means for controlling said air volume in dependence on the angular position of said actuating element relative to said housing, which pipette device is improved in that said actuating element is rotatably mounted in said housing by means of a nut (3), which is fixed to said housing, and of a screw (6), which is non-rotatably coupled to said actuating element and is screwed into and extends through said nut and is axially coupled to said piston, said actuating element (2) and said housing (1) being non-rotatably connected by an axially separable detent element joint (31, 32), said actuating element (2) being axially movable to establish and to eliminate said joint, said piston (56) being connected to a piston rod (7), said screw (6) being rotatable and axially movable in said nut (3) when said detent element joint (31, 32) has been separated, and said actuating element (2) being non-rotatably coupled to said screw (6) by a coupling (34, 35, 36 37) which causes said screw (6) to be rotated by said actuating element (2) when said detent element joint (31, 32) has been separated.
Claim 2
Dependent Claim
307 words
A pipetting device comprising: a housing having a top end, an actuating element, which protrudes from said top end and is depressible against spring action, a piston, which is axially connected to the actuating element, a cylinder, which is disposed in said housing and contains said piston, which is movable in said cylinder to move an air volume, a tubular pipette connector, which is adapted to be slidably fitted into a pipette tip, which connector and tip are open at both ends, means which connect said cylinder and said pipette connector and establish a fluid communication between the interior of said cylinder and the interior of said pipette connector, means by which said actuating element is rotatably mounted in said housing, and means for controlling said air volume in dependence on the angular position of said actuating element relative to said housing, which pipette device is improved in that said actuating element is rotatably mounted in said housing by means of a nut (3), which is fixed to said housing, and of a screw (6), which is non-rotatably coupled to said actuating element and is screwed into and extends through said nut and is axially coupled to said piston, said actuating element (2) and said housing (1) being non-rotatably connected by an axially separable detent element joint (31, 32), said actuating element (2) being axially movable to establish and to eliminate said joint, said piston (56) being connected to a piston rod (7), said screw (6) being rotatable and axially movable in said nut (3) when said detent element joint (31, 32) has been separated, and said actuating element (2) being non-rotatably coupled to said screw (6) by a coupling (34, 35, 36 37) which causes said screw (6) to be rotated by said actuating element (2) when said detent element joint (31, 32) has been separated.
Claim 3
Dependent Claim
13 words
A pipetting device according to claim 1, wherein said pipette connector is conical.
Claim 4
Dependent Claim
46 words
A pipetting device according to claim 1, wherein said actuating element (2) is non-rotatably coupled to said housing (1) by a torque-limiting coupling (73), which permits said screw (6) to be rotated by said actuating element (2) when said detent element joint (31, 32) is effective.
Claim 5
Dependent Claim
92 words
A pipetting device according to claim 1, wherein said actuating element comprises a knob (2), a knob carrier (11) is provided, which is axially movably mounted in and non-rotatably connected to said housing (1) and is axially coupled to said knob (2), said detent element joint comprises a first gear (32), which is non-rotatably connected to said housing (1), and a second gear (31), which is non-rotatably connected to said knob carrier (11) and is axially movable by said knob carrier into and out of meshing engagement with said first gear (32).
Claim 6
Dependent Claim
36 words
A pipetting device according to claim 4, wherein said first gear (32) has upwardly extending teeth (77-79; 98-100) meshing with said second gear (31) and said second gear (31) is disposed above said first gear (32).
Claim 7
Dependent Claim
24 words
A pipetting device according to claim 4, wherein said second gear (31) has radially inwardly extending teeth (76) meshing with said first gear (32).
Claim 8
Dependent Claim
81 words
A pipetting device according to claim 4, wherein at least one of said gears (31, 32) has resiliently yieldable teeth (84-87; 77-79; 92-94; 98-100) which mesh with the other of said gears and permit said gears to be rotated relative to each other even when said gears are in meshing engagement and the teeth of at least one of said gears are shaped to maintain said gears in meshing engagement even during a rotation of said gears relative to each other.
Claim 9
Dependent Claim
49 words
A pipetting device as set forth in claim 7, wherein the teeth of both of said gears (31, 32) consist of elastic blades, which are provided at their tips with enlarged portions (80-83; 88-91), which yieldably oppose an axial movement of said gears (31, 32) relative to each other.
Claim 10
Dependent Claim
17 words
A pipetting device according to claim 8, wherein said enlarged portions (80-83; 88-91) consist of spherical beads.
Claim 11
Dependent Claim
25 words
A pipetting device according to claim 8, wherein said enlarged portions are conical and taper in mutually opposite directions relative to said gears (FIG. 13).
Claim 12
Dependent Claim
43 words
A pipetting device according to claim 8, wherein said teeth (84-87; 77-79; 92-94; 98-100) consist of laterally yieldable blades and said teeth on at least one of said gears (31, 32) are provided with said enlarged portions (80-83; 88-91) only on one side.
Claim 13
Dependent Claim
70 words
A pipetting device according to claim 1, wherein a piston rod (7) which is axially coupled to said piston (56) extends between said piston (56) and a top end of said actuating element (2), and said piston rod (7) carries a stop (42), which cooperates with said screw (6) to define for said piston rod (6) an uppermost position relative to said screw (6) and in said actuating element (2).
Claim 14
Dependent Claim
67 words
A pipetting device according to claim 1, wherein said actuating element comprises a knob (2), which protrudes from the top end of said housing (1), a knob carrier (11) is non-rotatably and axially displaceably mounted in said housing (1) and is axially coupled to said knob (2), and a torque-limiting coupling (73) is provided, by which said knob (2) is non-rotatably connected to said knob carrier (11).
Claim 15
Dependent Claim
79 words
A pipetting device according to claim 13, wherein said torque-limiting coupling (73) comprises first and second coupling members (64, 11), said first coupling member (64) is elastic and formed with peripherally spaced apart recesses (65, 66) and said second coupling member (11) comprises elastic coupling means (67, 68) interengaging with said recesses (65, 66), one of said coupling members (64) is provided on said knob and the other of said coupling members is constituted by said knob carrier (11).
Claim 16
Dependent Claim
83 words
A pipetting device according to claim 13, wherein said knob carrier (11) is provided with axially extending, tonguelike spring elements (19, 20), which have radially inner ends provided with locking shoes (24, 25) and said piston rod (7) extends into said knob carrier (11) and is provided with axially spaced apart annular grooves (21, 22), which are adapted to receive said locking shoes (24, 25) in respective axial positions of said knob carrier (11) and said piston rod (7) relative to each other.
Claim 17
Dependent Claim
115 words
A pipetting device according to claim 1, wherein said actuating element comprises a knob (2), which protrudes from the top end of said housing (1) and comprises top and bottom parts, which are nonrotatably connected to each other, said knob (2) is carried by a knob carrier (11), which is mounted in said housing and provided with abutments and said top part comprises an elastic insert, which has outwardly spreadable elastic spring elements (12, 13), a piston rod (7) is axially coupled to and extends from said piston (56) into frictional engagement with said spring elements (12, 13) and said spring elements (12, 13) extend below and are axially engageable with said abutments (16, 17).
Claim 18
Dependent Claim
54 words
The improvement set forth in claim 16, wherein said knob (2) and said knob carrier (11) are connected by a knob connector (59), said knob (2) comprises a cover cap (9) having a depending shell (10) and said cover cap (9) is non-rotatably connected to said knob connector (59) by a torque-limiting coupling (73).
Claim 19
Dependent Claim
130 words
A pipetting device according to claim 17, wherein said knob connector (59) is provided at its top with a cylindrical extension (64) extending into said shell (10) and said torque-limiting coupling (73) comprises peripherally spaced apart recesses (65, 66) formed on the outside peripheral surface of said extension (64) and of radially inwardly extending, resiliently yieldable ribs (67, 68) which are provided on the inside surface of said shell (10) and extend into said recesses (65, 66), said recesses (65, 66), on the one hand, and said ribs (67, 68), on the other hand, have different pitch circles, and said cylindrical extension (64) is formed in said recesses (65, 66) and said shell (10) is formed on said ribs (67, 68) with enlarged portions, which face and overlap each other.
Claim 20
Dependent Claim
19 words
A pipetting device according to claim 18, wherein said ribs (67, 68) are elastically yieldable in a radial direction.