DE9301663U1 - Lid lock - Google Patents

Description

Applicant: Andreas Hettich H 2863-52-Gr

27.01.1993

Lid lock/3

The subject of the present innovation is a lid closure/3, in particular for rotor lids of centrifuges according to the preamble of claim 1.

Such a cover closure is known, for example, from EP 0 047 840. This cover closure is assigned to a rotor inner housing that rotates inside a stationary centrifuge housing and clamps the rotating inner housing cover firmly against the also rotating inner housing lower part.

The known lid closure consists of a handle part arranged on the top of the lid, which is connected through a lid opening to a locking sleeve on the bottom of the lid and aligned in the axial direction to the rotor rotation axis, thus securing the lid closure in the lid. This locking sleeve passes through a locking part designed as a hub with a conical inner circumference, with which the balls of the locking sleeve are brought into engagement by an actuating element which is axially displaceable in an axial through-hole of the lid closure, due to its shape, when inserted into the through-hole.

Balls move radially over the outer circumference of the locking sleeve.

However, this cover lock has proven to be disadvantageous because additional imbalances occur due to the lock rotating with the rotor inner housing, which can, among other things, lead to the actuating element slipping and thus the lock of the cover in the locking part becoming loose.

Another disadvantage of the known lid closure is that several manual movements are necessary to close and open the lid closure, whereby in particular to release the closure, i.e. to pull out the actuating element against the locking force of the balls acting in the radial direction, only one contact surface for fingertips is provided, which results in uncomfortable handling. Furthermore, due to the central arrangement of the actuating element and the small contact surface, two hands are generally required to put on and close the inner housing cover.

The aim of this innovation is therefore to create a lid closure that is more reliable in operation and can be operated quickly and easily.

To solve the problem posed, the innovation is characterized by the technical teaching of claim 1.

An essential feature of the lid closure according to the invention is that the locking part on the stationary

part of the centrifuge and the actuating element consists of a clamping knob with a central recess, on the inner circumference of which a control curve for actuating the balls is formed.

Since the locking element is now arranged on the stationary part of the centrifuge and the lid and the lid lock are also stationary and separate from the centrifuge rotor, disruptive imbalances caused by the lid lock on the rotor rotating at high speed are eliminated. The risk of the rotor coming loose is also almost completely eliminated.

A further advantage of the new lid closure is that the actuating element is designed as a clamping knob that surrounds the locking sleeve and can therefore be ergonomically designed in its external dimensions to be used as a handle and actuating part for the human hand. The clamping knob is dimensioned in such a way that the lid closure, and with it the entire rotor lid, can be held safely and comfortably in one hand in order to place the closure on the locking part and to lock or unlock the closure.

To lock or unlock the lid lock, the tension knob can be moved relative to the locking sleeve located in the central recess of the tension knob.

In this case, the tension knob for locking the closure is moved towards the fixed locking element, thereby simultaneously pressing the cover down onto the abutment, and the

the force required to tighten the balls on the locking element is reduced. Likewise, when unlocking the lid lock, the tension knob is simply moved away from the locking element, which means that the lock is released in one operation and the lid can be easily and quickly released from the stationary locking part.

In a particularly preferred embodiment, the actuating element is assigned a locking device that acts in the axial actuation direction. This locking device holds the tension knob in two displacement positions relative to the locking sleeve. The first position is reached when the balls are unlocked and the second position when the lid lock is locked and the tension knob is in its lowest displacement position. The locking device therefore holds the lid lock in the position it last occupied. When the lid lock is unlocked, it can be operated with one hand at any time. At the same time, the locking device holds the tension knob in the locked position and thus prevents the lid lock from being accidentally unlocked.

The locking element is designed as a locking pin, which is attached to the centrifuge housing and has at least one groove with a reduced diameter, which is followed by at least one conical shoulder in the axial direction of the locking pin, which serves as an engagement surface for the balls. Due to the circumferential surface tapering towards the locking groove, an additional closing force is exerted on the lid when the closure is locked, which then clamps it against the abutment. This keeps the lid closure under tension and prevents rattling or slight wobbling of the closure in the locked position.

avoided.

The subject matter of the present innovation arises not only from the subject matter of the individual protection claims, but also from the combination of the individual protection claims with one another.

All documents, including the summary, disclosed information and features, in particular the spatial configuration shown in the drawings, are claimed as essential to the invention insofar as they are new individually or in combination compared to the prior art.

The innovation is explained in more detail below using drawings that merely show one way of implementing it. The drawings and their descriptions reveal further key features and advantages of the innovation.

Show it:

Figure 1: the centrifuge housing mounted

Lid lock in unlocked position; 25

Figure 2: an enlarged view of detail Y from Figure 1;

Figure 3: a lid placed on the centrifuge housing in the locked state.

In Figure 1, a lid closure is shown which carries a rotor lid 6, which in turn rests on a centrifuge housing 26. The lid closure 1 is shown in the unlocked position and is on a

fixed to the fastening bolts 7 connected to the rotor 2 6 .

This lid closure 1 shown consists essentially of a tension knob 2, which has a continuous, central recess 9, in which a locking sleeve 3 is accommodated so as to be coaxially displaceable over a certain area. The locking sleeve 3 passes through a hub 17 formed in the lid 6 with its lower end and is fixed in its position relative to the lid 6 in the axial direction by means of saw rings 18. A locking pin 4 protrudes from below into the recess in the sleeve 3, which is open at the bottom. This locking pin 4 is screwed onto a threaded bolt 25 of the fastening bolt 7 by means of a blind hole 24 formed at its lower end and thus forms the locking part of the lid closure, which is connected in a fixed position to the centrifuge housing 26.

At its upper end, the essentially cylindrical locking pin 4 has a circumferential groove 22, the diameter of which is smaller than the outer diameter of the locking pin 4.

It is particularly advantageous if at least the groove flank facing the upper end of the locking pin 4 is designed as a conical shoulder 23 and is consequently designed in the shape of a conical surface from the smaller groove diameter up to the outer diameter of the locking pin 4. In the embodiment described here, the second groove flank is also turned in the shape of a conical surface.

The outer diameter of the locking pin 4 corresponds essentially to the inner diameter of the recess of the locking sleeve 3 and can therefore be inserted into the locking sleeve 3 with little play. In order to make it easier to thread the locking pin 4 into the locking sleeve 3, a chamfer 19 is formed at the upper end of the locking pin and the hole in the locking sleeve 3 is widened to close to the area of the cross holes.

This chamfer 19 simultaneously serves to press the balls 5, which are accommodated in bores 16 in the locking sleeve 3, outwards in a radial direction when the locking pin 4 is inserted or the locking sleeve 3 is placed on the locking pin.

In the embodiment shown here, the locking sleeve 3 has a total of three balls 5 evenly distributed over a circumferential line of the connecting sleeve 3, each of which is inserted into a hole with a diameter that corresponds to the ball diameter. Each of these holes 16 has a projection 21 at the end facing the inner diameter of the locking sleeve 3, which reduces the diameter of the holes and thereby prevents the balls 5 from falling through into the sleeve recess when the cover is not placed on the locking pin 4, but only partially protruding inwards in the radial direction over the inner diameter of the locking sleeve.

In the radial outward direction, the freedom of movement of the balls 5 is limited by the contour of the inner

circumferential surface of the central recess 9 of the clamping knob 2, so that the balls cannot fall out of the holes 16.

It is essential to the invention that the ball diameter is larger than the wall thickness of the locking sleeve 3.

The inner circumferential surface of the recess 9 of the tension knob 2 forms a control curve for actuating the balls 5.

For this purpose, a guide area 29 with an inner diameter that corresponds to the outer diameter of the locking sleeve 3 is formed in the recess 9. In the area of this guide area 29, the tension knob 2 slides along the outer circumferential surface of the locking sleeve 3.

An area 34 of the recess 9 with a larger inner diameter adjoins the guide area 29 at the top, thus forming a circumferential shoulder 10. This shoulder 10 serves as a stop for a shoulder 20 of the locking sleeve 3. The shoulder 20 is formed at the upper end of the locking sleeve 3 where the locking sleeve 3 has a diameter that is larger than the inner diameter of the guide area 9.

The shoulder 10 together with the step 20 0 forms the upper limit of the displacement path of the tension knob 2.

The contour of the recess 9 extends downwards from the guide area 29 over a transition area formed as a slope 15 into a cylindrical

-Q-

Area 30, the inner diameter of which is approximately equal to the outer diameter of the locking pin 4 plus twice the diameter of the ball 5. The axial distance of the area 30 to the shoulder 10 is selected so that when the tension knob 2 is at the upper stop, the area 30 is at approximately the same height as the holes 16. In this position, the balls can be moved radially outwards so far that they do not protrude into the inner recess of the locking sleeve 3 and the locking sleeve 3 can be easily placed on the locking pin 4.

The cylindrical area 30 is followed downwards by a further recess area 31, the inner diameter of which is larger than the largest diameter of the locking ring and washer 32 and which runs open towards the lower end face of the tensioning knob 2.

The axial distance of the front side 11 to the shoulder 10 of the clamping knob 2 is selected such that the distance of the front side 11 to the upper edge of the rib 33 of the cover 6 is at most so large that the clamping knob 2 can be moved downwards in the direction of the arrow 8 until the guide area 29 covers the holes 16 and the front side 11 rests on the ribs 33.

The locking sleeve 3 has in its upper area a groove 14 formed over its entire circumference, into which a snap ring 13 is inserted. The snap ring 13 is fixed in the groove 14 in the axial direction of the locking sleeve and rests in the area 34 on the inner circumferential surface of the recess 9 of the tension knob 2 in a spring-loaded manner. In the area 34, at an axial distance from the shoulder 10, a circumferential, radially

an inwardly projecting ramp 12 is formed which narrows the inside diameter of the recess 9 to a diameter that corresponds to the outside diameter of the locking sleeve at its upper front end. 05

If the tension knob 2 is now moved relative to the locking sleeve 3 in the direction of the arrow 8, the snap ring slides in the axial direction along the circumferential ramp 12.

Due to the radial spring force of the snap ring 13 and the axial force required to move the tension knob 3, the snap ring 13, in conjunction with the ramp, serves as a locking device for the tension knob 2 to prevent it from moving.

To lock the rotor lid 6 onto the centrifuge housing 26, the locking sleeve 3 is placed onto the locking pin 4 until the sealing edge 28 of the lid 6 rests on the front face 27 of the rotor 26. The lid lock 1 and the lid 6 then assume the position shown in Figure 3. Depending on the desired magnitude of the force with which the lid is to be pressed against the centrifuge container 26, the conical shoulder 23 on the locking pin 4 can be attached at different distances from the front face of the locking pin 4. The pressing force is then determined by the axial distance of the conical shoulder 23 from the centers of the balls 5 fixed in the axial direction on the one hand 0 and the spring constant of the rotor lid 6 on the other.

To lock the lid lock 1, starting from the position shown in Figure 1, the tension knob 2 is then manually applied and acting downwards in the direction of arrow 8.

downwards. Under this force, the cover 6 initially bends slightly until, after the equilibrium force is reached, a relative movement of the tension knob 2 relative to the locking sleeve begins.

Due to the elastic displacement of the lid closure 1, the locking sleeve 3 is moved downward relative to the locking pin 4 until the conical shoulder 23 is approximately at the height of the ball centers. Once this position is reached, the bevel 15 exerts a radial force component on the balls 5 and presses them inwards, whereby the balls 5 slide into the groove 14 on the one hand along the bevel 15 and on the other hand along the conical shoulder 23. The further the clamping knob 2 is moved downward, the further the balls 5 slide into the groove 14 until the balls 5 no longer protrude beyond the outer circumference of the locking sleeve and the guide area 29 is pushed completely over the holes 16 and the front side 31 of the clamping knob 2 rests on the upper edge of the rib 33.

In this position shown in Figure 3, the lid lock is locked and the lid 6 is clamped against the front side of the centrifuge housing 26. The counterforce required for this is applied via the locking sleeve 3 and the balls 5 to the conical shoulder 23 of the locking pin 4 and via this to the fastening bolt 7. In this locked state, only radial forces from the balls 5 act on the guide area 29 of the clamping knob 2. The axial forces are absorbed by the locking sleeve 3, and the snap ring 13 prevents the clamping knob 2 from moving inadvertently. Unlocking

The lid closure is thus excluded.

To open the lid lock, pull the tension knob 2 upwards by hand in the direction of arrow 8, whereby it is moved relative to the locking sleeve 3 and the previously described steps occur in reverse order until the starting position shown in Figure 1 is finally reached again.

The new lid closure creates a reliable closure for centrifuge lids that can be easily operated with one hand.

DRAWING LEGEND

1 Lid closure 2 Tension knob 3 Locking sleeve 4 Versen lu/3 tenons 5 Bullet 6 Lid 7 Fixing bolts 8th Arrow direction 9 Recess 10 shoulder 11 Front side 12 ramp 13 Snap ring 14 Groove 15 Slope 16 drilling 17 hub 18 Saw ring 19 Phasing 20 Paragraph 21 head Start 22 Groove 23 conical shoulder 24 Blind hole drilling 25 Threaded bolt

2 6 Rotor

27 Front side

28 Sealing edge

29 Management area

30 area, cylindrical

31 Recess area

32 Washer

3 3 Rib 34 Area

Claims (4)

20 Applicant: Andreas Hettich, PO Box 2 60 7200 Tuttlingen PROTECTION CLAIMS 25 30 35 1. Lid lock/3, in particular for rotor lids of centrifuges, consisting of a locking sleeve connected to the lid, which has balls which are arranged in radial holes arranged on the circumference of the locking sleeve and can be brought into engagement with a locking member by means of an axially displaceable actuating element and thereby clamp the lid against an abutment, characterized in that/3 the locking part is attached to the stationary part of the centrifuge Telex: 43 74 (patent-d) Telegram address: patri-lindau Bank accounts: B3yer. Vorainsbank Lindau (E) No. 125? 110 (Bl. Z 735 200 74)
Hypo-Bank L-nda ■> (B) No. 66 70-32 ¹ J 643 (BiJ! 733 204 42)
VolK-itMnk Lindau (B) No. 51 222 OM (Bi-Z 735 901 20) Postal checkTont* ~ Munich 414 848-808 (Bank code 700 100 80) ■ joint and the actuating element consists of a tension knob (2) having a central recess (9), on the inner circumference of which a control curve (12, 14, 15) is formed for actuating the balls (5). 2. Lid closure according to claim 1, characterized in that the actuating element is assigned a locking device (12, 13, 14) acting in the axial actuating direction (8). 3. Lid closure according to claim 1, characterized in that the locking element consists of a locking pin (4) which is fastened to the centrifuge housing and has at least one groove (22) with a reduced diameter, to which at least one conical shoulder (19, 23) adjoins in the axial direction of the locking pin (4). 4. Lid closure according to claim 1, characterized in that the locking sleeve (3) carries a fixed lid (6) which lies against the container (26).