Rotary evaporator having a fastening device with clamping elements

Abstract

The invention relates to a rotary evaporator comprising a rotary drive and a fastening device attached to the rotary drive and having a receiving space for receiving an evaporator flask rotatable by the rotary drive, wherein the fastening device comprises a connector section, in particular a ring-shaped connector section, at the rotary drive side and a retainer element, in particular a ring-shaped retainer element, at the evaporator flask side that coupled to the connector section and that is rotatable relative to the connector section between a starting position and an end position. The fastening device comprises at least one clamping element that is moved, on the rotation of the retainer element relative to the connector section from the starting position into the end position, from a release position radially inwardly into a holding position in which the respective clamping element projects into the receiving space to hold a flange-shaped connection region of an evaporator flask received in the receiving space of the fastening device in a form-fitting and/or force-fitting manner and to secure it against a removal from the receiving space.

Claims

1. A rotary evaporator comprising a rotary drive and a fastening device attached to the rotary drive and having a receiving space for receiving an evaporator flask rotatable by the rotary drive, wherein the fastening device comprises a connector section at the rotary drive side and a retainer element at the evaporator flask side that is coupled to the connector section and that is rotatable relative to the connector section between a starting position and an end position, wherein the fastening device comprises at least one clamping element that is moved, on the rotation of the retainer element relative to the connector section from the starting position into the end position, from a release position radially inwardly into a holding position in which the respective clamping element projects into the receiving space to hold a flange-shaped connection region of an evaporator flask received in the receiving space of the fastening device in a form-fitting and/or force-fitting manner and to secure it against a removal from the receiving space, the rotary evaporator further comprising means that convert a rotation of the retainer element relative to the connector section from the starting position into the end position into an axial movement of the retainer element relative to the connector section, with further means being provided that convert the axial movement of the retainer element into the radial movement and simultaneously the axial movement of the respective clamping element, wherein the further means comprise the respective clamping element being chamfered at its radially outer edge facing the connector section and the connector section having a chamfer corresponding hereto, and wherein the respective clamping element is moved, on a rotation of the retainer element relative to the connector section from the starting position into the end position, radially inwardly and simultaneously axially toward the connector section.

2. The rotary evaporator in accordance with claim 1, wherein the connector section is fastened to the rotary drive.

3. The rotary evaporator in accordance with claim 1, wherein the retainer element is releasably couplable to the connector section.

4. The rotary evaporator in accordance with claim 1, wherein the coupling of the retainer element to the connector section takes place free of a screw connection.

5. The rotary evaporator in accordance with claim 1, wherein the retainer element can be placed onto the connector section into the starting position in one or more discrete rotational positions.

6. The rotary evaporator in accordance with claim 1, wherein the connector section comprises a plurality of radially outwardly projecting first engagement elements and the retainer element comprises a plurality of radially inwardly projecting second engagement elements, with the first engagement elements and the second engagement elements meshingly engaging into one another in the starting position and engaging behind one another in a rotated position.

7. The rotary evaporator in accordance with claim 6, wherein the first engagement elements and the second engagement elements are each arranged evenly distributed in the peripheral direction at the connector section and at the retainer element, respectively.

8. The rotary evaporator in accordance with claim 1, wherein the respective clamping element is arranged between the connector section and the retainer element.

9. The rotary evaporator in accordance with claim 1, wherein, on the rotation of the retainer element relative to the connector section from the starting position into the end position, the respective clamping element is pressed by the retainer element axially toward the connector section.

10. The rotary evaporator in accordance with claim 1, wherein the means comprise mutually corresponding sloping surfaces that are formed at the connector section, on the one hand, and at the retainer element, on the other hand.

11. The rotary evaporator in accordance with claim 1, wherein the respective clamping element is chamfered at its radially inner edge facing the connector section to cooperate with a chamfer corresponding hereto at the flange-shaped connection region of an evaporator flask received in the fastening device.

12. The rotary evaporator in accordance with claim 1, wherein the respective clamping element is preloaded from its holding position into the release position.

13. The rotary evaporator in accordance with claim 12, wherein a circlip is provided to preload the respective clamping element.

14. The rotary evaporator in accordance with claim 1, wherein the respective clamping element is elongated and/or is of part-circle shape.

15. The rotary evaporator in accordance with claim 1, wherein a plurality of clamping elements are arranged evenly distributed in the peripheral direction.

16. The rotary evaporator in accordance with claim 1, wherein the respective clamping element cooperates with a respective first engagement element of the connector section.

17. The rotary evaporator in accordance with claim 1, wherein the retainer element is provided with a tensioning lever for rotation, with an end of said tensioning lever being pivotably supported at an articulation point at the retainer element and being adjustable between an open position and a closed position in which the respective clamping element adopts the holding position.

18. The rotary evaporator in accordance with claim 17, wherein the tensioning lever is coupled to the retainer element and to the connector section such that the rotation of the retainer element relative to the connector section from the starting position into the end position takes place in two stages, with in a first stage the retainer element being rotated with an open tensioning lever from the starting position by a first part distance into an abutment position for the tensioning lever, and with in a second stage the tensioning lever being closed in a second stage to rotate the retainer element from the abutment position by a second part distance into the end position.

19. The rotary evaporator in accordance with claim 18, wherein the first part distance is longer than the second part distance.

20. The rotary evaporator in accordance with claim 18, wherein the rotating back of the retainer element relative to the connector section from the end position into the starting position takes place in two stages, with the tensioning lever being opened to rotate the retainer element by the second part distance from the end position in a first stage and with the retainer element being rotated back into the starting position with an open tensioning lever in a second stage.

21. The rotary evaporator in accordance with claim 17, wherein the longitudinal extent of the tensioning lever extends in the peripheral direction of the retainer element; wherein the tensioning lever is of part-circle shape and/or is received in a radially outer recess of the retainer element in the closed position.

22. The rotary evaporator in accordance with claim 17, wherein pivot range of the tensioning lever between the open position and the closed position amounts to no more than 120.

23. The rotary evaporator in accordance with claim 17, wherein the tensioning lever acts as a toggle lever on closing to rotate the retainer element from the abutment position by a second part distance into the end position.

24. The rotary evaporator in accordance with claim 17, further comprising a control arm having a first end and a second end, with the first end being pivotably supported at the connector section and with the second end being in engagement via a guide element with a control cam, with the control cam being formed at the tensioning lever.

25. The rotary evaporator in accordance with claim 24, wherein the first end of the control arm is pivotably supported at a tensioning element that is inserted into a correspondingly configured mount of the connector section that prevents a rotation of the tensioning element relative to the connector section.

26. The rotary evaporator in accordance with claim 25, wherein the tensioning element is inserted between two radially outwardly projecting engagement elements of the connector section.

27. The rotary evaporator in accordance with claim 24, wherein the control cam has a first section and a second section adjoining it at an angle at a kink point, with the second section having an end point.

28. The rotary evaporator in accordance with claim 27, wherein, in the closed position of the tensioning lever, the first section extends tangentially and/or, in the open position, extends radially to the retainer element; and/or wherein the second section is angled away from the retainer element with respect to the first section in the closed position of the tensioning lever.

29. The rotary evaporator in accordance with claim 27, wherein the guide element is at a starting point in the first section in the starting position of the retainer element and is traveled by a first part distance toward the end point on the rotation of the retainer element relative to the connector section; and/or wherein the guide element remains at the end point on a rotation of the retainer element by a second part distance relative to the connector section.

30. The rotary evaporator in accordance with claim 27, wherein the guide element is traveled by the second part distance to the kink point on a rotating back of the retainer element relative to the connector section; and/or wherein the guide element is traveled by the first part distance to the starting point on a rotating back of the retainer element relative to the connector section.

31. The rotary evaporator in accordance with claim 24, wherein the control arm is longitudinally adjustable.

32. The rotary evaporator in accordance with claim 31, wherein a starting point of the guide element in the first section of the control cam is adjustable via the length of the control arm.

33. The rotary evaporator in accordance with claim 17, wherein a latching device is provided to latch the tensioning lever to the retainer element in the closed position.

34. The rotary evaporator in accordance with claim 1, wherein the radially inner edge of the retainer element remote from the connector section is provided with an outer edge protective ring and/or the radial inner edge of the connector section facing the retainer element is provided with an inner edge protective ring.

35. The rotary evaporator in accordance with claim 34, wherein the radially inner edge of the outer edge protective ring remote from the connector section is chamfered; and/or the radially inner edge of the inner edge protective ring facing the retainer element is chamfered.

36. The rotary evaporator in accordance with claim 34, wherein the largest inner diameter of a chamfer of the inner edge protective ring is not smaller than the smallest inner diameter of a chamfer of the outer edge protective ring.

Description

(1) Further developments of the invention are also set forth in the dependent claims, in the description and in the enclosed drawing.

(2) Non-restricting embodiments of the invention are shown in the drawing and will be described in the following. There are shown,

(3) FIG. 1 a perspective view of a fastening device in accordance with the invention for a rotary evaporator;

(4) FIG. 2 the fastening device of FIG. 1 in a frontal view;

(5) FIG. 3 a longitudinal section through the fastening device of FIG. 1 along the line A-a in FIG. 2 with an inserted evaporator flask;

(6) FIG. 4 an exploded representation of the fastening device of FIG. 1;

(7) FIG. 5 a cross-section through the fastening device of FIG. 1 along the line B-B in FIG. 3, with a retainer element being shown in a first rotational position and a tensioning lever in an open position;

(8) FIG. 6 the view of FIG. 5, with the retainer element being rotated clockwise by a part of a first part distance;

(9) FIG. 7 the view of FIG. 5, with the retainer element being rotated clockwise by a first part distance;

(10) FIG. 8 the view of FIG. 7, with the tensioning lever being partly closed; and

(11) FIG. 9 the view of FIG. 7, with the tensioning lever being completely closed.

(12) The fastening device in accordance with the invention for an evaporator flask 77 of a rotary evaporator shown in FIGS. 1 to 4 first comprises a ring-shaped connector section 11 that can be screwed to a hub, not shown, of a rotary drive of a rotary evaporator located at the left of the connector section 11 in FIG. 3. The connector section 11 has a connector stub 13 at which three radially outwardly projecting first engagement elements 15 are provided that are arranged distributed evenly in the peripheral direction. The fastening device furthermore comprises a ring-shaped two-part retainer element 17 that comprises a bayonet ring 19 and a carrier ring 21. The two rings 19, 21 are screwed to one another, i.e. are fixedly connected to one another. The bayonet ring 19 has a number of radially inwardly projecting second engagement elements 23 corresponding to the number of first engagement elements 15, i.e. three second engagement elements 23 that are provided equally distributed at the bayonet ring 19 in the peripheral direction.

(13) To install the fastening device, the retainer element 17 is placed axially onto the connector section 11 in one of three possible rotational positions such that the first engagement elements 15 and the second engagement elements 23 engage meshingly with one another or slide past one another. The retainer element 17 is subsequently releasably removably held at the connector section 11 by an installation screw 25 that extends through a bore in the carrier ring 21 behind one of the first engagement elements 15. The retainer element 17 is then located in a starting position relative to the connector section 11. The inner space surrounded by the connector section 11 and by the two rings 19, 21 provides a receiving space 73 in which a flange-shaped connection region 75 of an evaporator flask 77 can be received.

(14) The retainer element 17 can be rotated from this starting position relative to the connector section 11 into an end position in which the aforesaid flange-shaped connection region 75 of an evaporator flask 77 received in the receiving space 73 of the fastening device is held in a form-fitting and/or force-fitting manner. In this respect, the first and second engagement elements 15, 23 engage behind one another. Since the axial side surfaces of the first engagement elements 15 directed to the left in FIG. 4 are each provided with a first sloping surface 27 and since the axial side surfaces of the second engagement elements 23 directed to the right are each provided with a second sloping surface 29 corresponding thereto, the rotational movement 47 of the retainer element 17 from the starting position into the end position is converted into an axial movement 49 of the retainer element 17 to the connector section 11 (cf. FIG. 3). On a rotation of the retainer element 17 relative to the connector section 11, the connector section 11 is advantageously rotationally fixedly held.

(15) Three clamping elements 31 arranged evenly distributed in the peripheral direction are provided between the connector section 11 and the retainer element 17. In this respect, the clamping elements 31 are each supported at one of the first engagement elements 15. The clamping elements 31 are each elongated in the peripheral direction and are of part-circular shape. On a rotation of the retainer element 17 from the starting position into the end position, a radially inwardly projecting ring web 33 formed at the retainer element 17 presses the clamping elements 31 axially toward the first engagement elements 15. Since the clamping elements 31 each have a chamfer 35 at their radially outer edges facing the connector section 11 and since the first engagement elements 15 have a chamfer 37 respectively corresponding therewith, the clamping elements 31 travel radially inwardly and axially toward the connector element 11 on a rotation of the retainer element 17, i.e. the axial movement 49 of the retainer element 17 is converted into a combined radial and axial movement 51 of the clamping elements 31 (cf. FIG. 3).

(16) The clamping elements 31 are traveled, on a rotation of the retainer element 17 from the starting position into the end position, from a release position in which the clamping elements 31 are retracted from the receiving space 73 of the fastening device into a holding position in which the clamping elements 31 project into the receiving space 73 such that a flange-shaped connection region 75 of an evaporator flask 77 received in the receiving space 73 can be clampingly held in a form-fitting and force-fitting manner. The clamping holding is in particular achieved in that the clamping elements 31 have a further chamfer 39 at their radially inner edges facing the connector section 11, said chamfer clampingly pressing onto a chamfer 41 corresponding thereto at the aforesaid flange-shaped connection region 75 of the evaporator flask 77 (FIG. 3). To release the evaporator flask 77 again for a removal from the receiving space 73 on the rotating back of the retainer element 17, a circlip 43 is provided that engages at a radial inner surface of the clamping elements 31 and presses it radially outwardly under a preload.

(17) The retainer element 17 is provided with a tensioning lever 53 for rotation. An end of the tensioning lever 53 is pivotably supported at an articulated point at the retainer element 17 and is adjustable between the open position shown in FIGS. 5 to 7 and the closed position shown in FIG. 9 in which the clamping elements 31 adopt their holding position, with the two positions bounding a pivot region of at least substantially 90. The tensioning lever 53 is of part-circular shape and its longitudinal extent runs in the peripheral direction of the retainer element 17. To integrate the tensioning lever 53 in the retainer element 17, a recess 55 is formed at a radial outer side of the retainer element 17 and the tensioning lever 53 is received therein in the closed position.

(18) A control arm 57 is furthermore provided whose first end is pivotably supported at a tensioning element 59. The tensioning element 59 is inserted into the space between two first engagement elements 15 of the connector section 11 such that a rotation of the tensioning element 59 relative to the connector section 11 is not possible. The second end of the control arm 57 engages via a cylinder pin 61 into a control cam 63 formed as a guide slot in the tensioning lever 53. The control cam 63 has a first straight section 65 and a second straight section 67 having an end point 69, wherein the second section 67 adjoins a kink point at the first section 65 in an angled manner. The first section 65 extends tangentially in the closed position of the tensioning lever 53 and radially to the retainer element 17 in the open position of the tensioning lever 53. The second section 67 is inclined away from the retainer element 17 with respect to the first section 65 in the closed position of the tensioning lever 53.

(19) The fastening or releasing of a flange-shaped connection region 75 of an evaporator flask 77 received in the receiving space 73 of the fastening device takes place as follows:

(20) In FIG. 5, the retainer element 17 is in its starting position, the clamping elements 31 are in their release position and the tensioning lever 53 is open. In this state of the fastening device, a flange-shaped connection region 75 of an evaporator flask 77 is introduced into the receiving space 73 of the fastening device.

(21) Subsequently in a first step, the retainer elements 17 is rotated by a first part distance with an open tensioning lever 53 from the starting position clockwise with respect to the connector element 11 until the cylinder pin 61 that is still at its starting point in FIG. 5 abuts the end point 69 of the control cam 63. This corresponds to an abutment position for the tensioning lever 53. A further rotation of the retainer element 17 with an open tensioning lever 53 is then no longer possible. Due to the sloping surfaces 27, 29 formed at the first and second engagement elements 15, 23 and the chamfers 35, 37 formed at the clamping elements 31 and at the first engagement elements, the rotational movement of the retainer element 17 is ultimately converted into a movement of the clamping elements 31 with a radially inwardly directed component from their release position, i.e. the clamping elements 31 approach their holding position in which they clampingly embrace the flange-shaped connection region 75 of the evaporator flask 77 inserted into the receiving space 73 of the fastening device. This is shown in FIGS. 6 and 7.

(22) The tensioning lever 53 is then closed in a second step. In this respect, the retainer element 17 is further rotated by a second part distance that is substantially shorter in comparison with the first part distance into its end position. The further rotation of the retainer element 17 by the second part distance is ultimately due to the fact that the articulation point 71 of the tensioning lever 53 is moved clockwise in the manner of a toggle lever on the closing of the tensioning lever 53. The cylinder pin 61 in this respect does not move out of the end point 69, i.e. the closing of the tensioning lever 53 takes place about an axis of rotation stationary with respect to the tensioning lever 53. The clamping elements 31 are traveled onward with a radially inwardly directed component to reach their holding position in the closed position of the tensioning lever 53, in which holding position they clampingly hold the flange-shaped connection region 75 of the inserted evaporator flask 77. This is shown in FIGS. 8 and 9.

(23) To be able to remove the evaporator flask 77 from the fastening device again, the tensioning lever 53 is opened again in a first step, whereby the retainer element 17 is rotated back by the second part distance. In the first stage, the cylinder pin 61 runs back up to the kink point between the two sections 65, 67 of the control cam 63, with substantially no force having to be applied by an operator in this respect. In a second stage, the retainer element is then rotated back by the first part distance into the starting position with an open tensioning lever 53 by tightening at the tensioning lever 53 and the cylinder pin 61 runs back to its starting point. Due to its preload, the circlip 43 provides that the clamping elements 31 are also again pressed radially outwardly from the receiving space 73 back in the direction of their release position in both stages.

(24) The control arm 57 is adjustable in its length. For this purpose, the control arm 57 comprises a tensioning screw 79 and a clamping nut 81. The starting point of the cylinder pin 61 in the control cam 63 and the tightening torque exerted by the tensioning lever 53 in the closed position can be set via the length of the control arm 57. A catch 83 with whose aid the tensioning lever 53 can be latched to the retainer element 17 and that is pivotably supported in the tensioning lever 53 and is preloaded into a latching position, for example by means of a yoke spring, is furthermore provided. For this purpose, the catch 83 engages into a latching mount formed in the retainer element 17 and in so doing engages behind a latching edge of the latching mount.

(25) The fastening device furthermore comprises an outer edge protective ring 85 and an inner edge protective ring 87. The outer edge protective ring 85 is provided, in particular clipped, at the radially inner edge of the retainer element 17 remote from the connector section 11 and is chamfered at its radially inner edge remote from the connector section 11. The inner edge protective ring 87 is provided, in particular pressed, at the radially inner edge of the connector section 11 facing the retainer element 17 and is chamfered at its radially inner edge facing the retainer element 17. A centering function can additionally be ensured by the two edge protective rings 85, 87 on the insertion of a flange-shaped connection region of an evaporator flask. In this respect, the largest inner diameter of the chamfer of the inner edge protective ring 87 is in particular not smaller than the smallest inner diameter of the chamfer of the outer edge protective ring 85. A sealing device 89 is furthermore provided that is clamped between the flange-shaped connection region 75 of the evaporator flask 77 and the connector section 11 on the coupling of the retainer element 17 to the connector section 11.

REFERENCE NUMERAL LIST

(26) 11 connector section 13 connector stub 15 first engagement element 17 retainer element 19 bayonet ring 21 carrier ring 23 second engagement element 25 installation screw 27 first sloping surface 29 second sloping surface 31 clamping element 33 ring web 35 chamfer 37 chamfer 39 chamfer 41 chamfer 43 circlip 47 rotational movement 49 axial movement 51 combined radial and axial movement 53 tensioning lever 55 recess 57 control arm 59 tensioning element 61 cylinder pin 63 control cam 65 first section 67 second section 69 end point 71 articulation point 73 receiving space 75 flanged-shaped connection region 77 evaporator flask 79 tensioning screw 81 clamping nut 83 catch 85 outer edge protective ring 87 inner edge protective ring 89 sealing device