EP0037955B1

EP0037955B1 - Vortexer

Info

Publication number: EP0037955B1
Application number: EP81102413A
Authority: EP
Inventors: Bruce R. Koball; Robert A. Bilbrey
Original assignee: Scientific Manufacturing Industries Inc
Current assignee: American Hospital Supply Corp
Priority date: 1980-04-08
Filing date: 1981-03-31
Publication date: 1984-02-08
Also published as: EP0037955A3; DE3162153D1; EP0037955A2

Description

The present invention relates generally to apparatus for producing a vortex and to the mixing of liquids contained in laboratory vessels such as test tubes.
Known arrangements can be seen in GB-A-1,240,592 and GB-A-931,263.
According to the present invention there is provided a vortexer apparatus having a base, a motor mounted to said base, an agitated platform resiliently supported from said base and connected to said motor by an eccentric crank, a hold down plate, an upright cylindrical support mounted to said base, and means for detachably and selectively mounting said hold down plate, characterized by said support having a pair of splines formed thereon, the end of one spline being spaced from the near end of the other spline by a circumferential groove; said means for detachably mounting said hold down plate to said support including an elongate sleeve axially engageable with said support and having a key engageable with said pair of splines and groove; and said pair of splines being formed in an axial misalignment relative to each other, a rotation of said plate and sleeve being necessary to move said key from an alignment with one spline to an alignment with the other spline.
A fuller understanding of the invention, its objects and features will become apparent from the following detailed description of an embodiment thereof.
In the drawings forming a part of this application and in which like parts are identified by like reference numerals,

Fig. 1 is a perspective view of a preferred embodiment of the invention in a vortexer apparatus;
Figs. 2, 3 and 4 illustrate various sizes of laboratory vessels and holders which may be used with the vortexer apparatus;
Fig. 5 is an elevation of the vortexer viewed on line 5-5 of Fig. 1;
Fig. 6 is an elevation of the vortexer viewed on line 6-6 of Fig. 1;
Fig. 7 is a plan view and partial section taken on line 7-7 of Fig. 6; and

Referring to Figs. 1, 5 and 6 in particular, the vortexer apparatus generally comprises a base 10, a motor 11 mounted to said base, an agitated platform 12 resiliently supported from the base and connected to motor 11 by an eccentric crank and coupling 13. Agitated platform 12 is resiliently supported upon a set of four wires 14, the lower end of each wire being secured in a holder 15 mounted to base 10. A housing 16 essentially encloses motor 11, wire 14 and the operating circuitry of the vortexer. This arrangement of apparatus is essentially known and is utilized in connection with other forms of vortexer apparatus.
The present arrangement has improved means for mounting a hold down plate 20 relative to agitated plate 12 and base 10. For this purpose there is provided a cylindrical support or support spindle 21, secured to base 10 by a screw 22, and maintained upright by housing 16. A torque arm 23 is fitted to the lower portion of support spindle 21, and made a part thereof either with a force fit or by welding, and the torque arm is secured to the housing 16 by a set screw 24. Torque arm 23 is provided with a slot 23a which allows the torque arm to be angularly pivoted relative to the base through small angles of adjustment and then secured by a set screw 24 when properly located. Slight angular adjustments of the torque arm and support spindle 21 are made by an eccentric 25 threadably received in housing 16. The upper end of eccentric 25 carries a pin 25a, said pin being offset relative to the axis of threading and received in an opening 23b of the torque arm. This arrangement is best shown in Fig. 7.
The angular orientation of support spindle 21 is of importance in locating the hold down plate 20 directly above agitated platform 12. The mechanism provided for angularly positioning spindle 21 allows this to be done quite easily at the time of assembly, notwithstanding a manufacture of parts which may vary slightly in size and be built to loose tolerances.
Support spindle 21 is formed with a pair of splines 21 a and 21 b, the lower end of upper spline 21 a being spaced from the upper end of lower spline 21 b by a circumferential groove 21 c. It will be further noted that the pair of splines 21 a and 21 are formed on opposite sides of support 21 in an axial misalignment relative to each other.
Plate 20 is adapted to be mounted to and supported from spindle 21 through an elongate sleeve 26, the internal diameter of sleeve 26 being only slightly greater than the outer diameter of support spindle 21. A key 27 is secured to sleeve 26, said key being engageable with either of said pair of splines 21 a or 21 b, or groove 21 c, when properly aligned therewith. In the position shown in Figs. 5 and 6, key 27 is engaged with spline 21 b, and in that position allows hold down plate 20 to be lowered upon a set of laboratory test tubes T supported in a rack R. Although the weight of plate 20 may be sufficient to hold the upper ends of each tube T in a relatively fixed or steady position, the hold down pressure may be increased. For this purpose a set screw 28 is provided to secure sleeve 26 at a set position along support spindle 21. To increase the pressure above that provided by the weight of plate 20 alone, hand pressure is applied ot the top of plate 20 with set screw 28 backed off. With the desired or necessary pressure applied, set screw 28 is then threaded into engagement with the surface of spindle 21. If desired, indentations may be formed along spindle 21 to receive the end of the set screw in various "set" positions.
Fig. 1 illustrates in broken line a position for hold down plate 20 allowing removal of rack R and test tubes T. This position is attained simply by backing off set screw 28, lifting plate 20 until key 27 extends beyond spline 21 b and becomes aligned with groove 21 c, and then rotating plate 20. Key 27 will then track within groove 21 c supporting plate 20 at that position.
It will be further seen that plate 20 and sleeve 26 may be removed entirely from spindle 21 by simply rotating plate 20 until key 27 becomes aligned with spline 21 a, then lifting the plate and sleeve 26 axially from the spindle support.
Figs. 2, 3 and 4 illustrate various types of racks and vessels which may be utilized in connection with the vortexer. Such racks and vessels are commonly known and used in connection with other vortexers.

Claims

1. A vortexer apparatus having a base (10), a motor (11) mounted to said base, an agitated platform (12) resiliently supported from said base and connected to said motor by an eccentric crank (13), a hold down plate (20), an upright cylindrical support (21) mounted to said base, and means for detachably and selectively mounting said hold down plate, characterized by said support (21) having a pair of splines (21a, 21b) formed thereon, the end of one spline being spaced from the near end of the other spline by a circumferential groove (21 c); said means for detachably mounting said hold down plate to said support including an elongate sleeve (26) axially engageable with said support and having a key (27) engageable with said pair of splines and groove; and said pair of splines being formed in an axial misalignment relative to each other, a rotation of said plate (20) and sleeve (26) being necessary to move said key (27) from an alignment with one spline to an alignment with the other spline.

2. The vortexer apparatus of claim 1 characterized by a torque arm (23) for rotationally locating said cylindrical support (21) on said base (10), said torque arm being secured to said support and having a slot (23a) engageable with a set screw (24) threaded to said base.

3. The vortexer apparatus of claim 2, characterized by the feature that said torque arm (23) has an opening (23b); and an eccentric (25) mounted to said base (10), said eccentric having a pin (25a) received in the opening (23b) of said torque arm (23), the rotational position of said eccentric locating said torque arm and cylindrical support (21) relative to said base.

4. The vortexer apparatus of claim 1, 2 or 3, characterized by a set screw (28) threadably secured in said sleeve (26) and engageable with said cylindrical support (21) when said key (27) is engaged with the lower one of said pair of splines (21 a, 21 b).