Blood sampling device with a vacuum tube

A blood sampling device has a vacuum tube and a sleeve provided with a two-ended needle. When one end of the needle is placed in a vein in order to take a blood sample, a seal in the vacuum tube is perforated by the second end of the needle so as to create suction for taking a blood sample. The sleeve comprises a base with an outlet and guide aperture, and a tubular section for guiding and protecting the first end of the needle. The sleeve includes a guiding and locking groove with two locking positions. The locking positions consist of a longitudinal section corresponding substantially to the movement which the needle has to perform in order to pass from its retracted position into its operating position and terminating at each end in a locking extension which is transverse relative to the sliding direction and which corresponds to each of the two locking positions. The needle is provided with a guiding and locking disc placed in the sleeve and comprises at least one tab accommodated in the groove and accessible from the exterior of the sleeve. Accordingly, the sleeve can be passed manually from its locked retracted position into a locked operating position such that the needle is outside of the sleeve. The guiding and locking disc comprises a fastener on its rear face. The plug of the vacuum tube connects to the rear face of the guiding and locking disc.

BACKGROUND OF THE INVENTION 
The present invention relates to a blood sampling device with a vacuum tube 
of the type comprising a sleeve provided with a two-ended needle of which 
the first end is to be injected into the patient and the second end is to 
perforate the plug in the vacuum tube which is placed in the sleeve and 
which, when the first end has been placed in the vein to take the blood 
sample, is fitted onto the other end of the needle so as to create suction 
for taking the blood sample. 
In order to take the blood sample, the tube is partially engaged in the 
sleeve but is prevented from being fitted onto the needle. The patient is 
then injected and the tube pressed down onto the needle so as to perforate 
its plug. The vacuum prevailing in the tube thus creates low pressure 
which draws the blood into the tube. At the end of this sampling step, the 
tube is extracted from the sleeve. The needle and sleeve may be left in 
place in order for a further sample to he taken from the same patient. If 
this is not desired, the needle is extracted and has to be fitted with a 
cap before disposal. The needle must then be unscrewed and a further cap 
fitted onto the rear part of the needle. 
This operation requires a certain amount of cars and the user may possibly 
prick himself and thus risk contamination. 
The aim of the present invention is to overcome these disadvantages and 
proposes creating a blood sampling device with a single-use vacuum tube 
which has a simple structure and provides particularly effective 
protection against all risk of injury by the needle. 
To this end, the invention relates to a blood sampling device with a vacuum 
tube characterised by the means set out in the claims. 
SUMMARY OF THE INVENTION 
The disposable device according to the invention has the advantage of an 
extremely simple structure made of the same materials as the known device 
and thus eliminating all the problems involved in material compatibility. 
This device is far simpler than the known device since the needle no 
longer has to be placed in a cap and sterile packaging in order to be 
secured on the front end of the sleeve accommodating the vacuum tube. On 
the contrary, the assembly formed by the sleeve and the needle is already 
assembled which reduces the number of parts and consequently the cost. In 
view of the considerable number of such devices used daily in hospitals, 
this problem of reducing costs combined with a considerable improvement in 
safety when the device is used constitutes an extremely significant 
advance. 
The device according to the invention is very easy to use and there is no 
risk of the user pricking himself at any moment when positioning the 
needle and in particular when withdrawing the needle, in particular since 
he is obliged to hold the sleeve of the device in one hand and the tube in 
the other in order to unlock then pull the guiding disc and thus the 
needle into its retracted position. 
The operation is thus limited to action on parts which are relatively far 
away from the tip of the needle used to inject the patient and the 
fastening of the disc to the tube plug such that these two parts are 
rendered rotationally integral enables the unlocking and withdrawal 
movement of the needle to be performed at the end of the operation: as a 
result of the tube being rotated, the guiding disc is rotated (fastening 
between the tube plug and the pins), then as a result of pulling on the 
tube, the needle is drawn via its rear part thanks to the constriction of 
the rubber and the weight of the needle, the device being turned around 
for this operation (tip of the needle--at the patient end --turned 
upward). The needle and its guiding and locking part can be introduced 
during manufacture as a result of the resilience of its sleeve walls being 
altered in order to pass along the excess thickness represented by the 
tabs until they appear in the opening in the groove. 
For this assembly it is also possible to provide a sleeve which is split at 
the rear such that the tabs can pass into the groove. 
In accordance with a further feature, the sleeve comprises a second groove 
in a position which is diametrically opposite the axis of the sleeve and 
has a shape which is symmetrical relative to the axis of the sleeve. 
Although the grooves and their corresponding tabs can be provided in 
asymmetrical positions which are not diametrically opposite, it is 
preferable if they are in order that the stresses are better distributed 
and the sliding movements facilitated. 
The present invention will be described below in further detail with 
reference to the attached drawings.

DETAILED DESCRIPTION OF THE INVENTION 
In accordance with FIG. 1, the blood sampling device with a vacuum tube 
according to the invention, which is only shown in part, consists of a 
sleeve 11 of which the base 12 is provided with an aperture 13 for the 
passage and guiding of the needle 14. 
The needle 14 has two ends 141, 142, the first end 141 being used to inject 
the patient and the second end 142 being used to perforate the plug of the 
vacuum tube introduced into the sleeve from the right hand side toward the 
left hand side as viewed in FIG. 1 (arrow A ). 
The needle 14 is provided with a guiding and locking disc 15 placed in the 
sleeve 11 and comprising two tabs 151, 152 which are accessible from the 
exterior of the sleeve 11 and are accommodated in grooves 161, 162 
provided in the wall of the sleeve 11. As shown in FIG. 1, the tabs 151, 
152 are diametrically opposite relative to the longitudinal axis of the 
sleeve 11, as are the grooves 161, 162 which accommodate them. 
The plan view of FIG. 2A shows the shape of the groove 162. 
As a result of the two tabs 151, 152 being acted upon, the needle 14 can 
thus be passed from the retracted position shown in FIG. 1 into the 
delivery position as a result of the assembly formed by the needle 14 and 
the guide disc 15 being advanced in its groove. 
At each end of the groove 162 there is a locking position 16A, 162B 
enabling the disc 15 to be rotated about its axis represented by the 
needle as a result of the rotational movement of the disc 15. This 
movement is achieved by a transverse rotation along the axis of the needle 
(double arrow BR) enabling the tab 151 corresponding to this groove 162 to 
be passed either into the locking position 162A or in the groove 162 
permitting the slide movement (double arrow B). The function of the 
locking position 162B at the other end of the groove 162 is to enable the 
tab 151 to be blocked when the needle 14 is in the operating position. 
In the simplest case shown in FIG. 2A, the groove 162 comprises a 
longitudinal section connecting the two locking positions. This 
longitudinal section is parallel with the sleeve axis. This is only one 
particular embodiment, the advantage of which is its simplicity. 
The division into two of the extension, i.e. the presence of the tab 152 in 
addition to the tab 151, enables the device to be produced symmetrically 
preventing the disc 15 from seizing under the force of translation. 
At its rear the disc 15 comprises fastening means such as pins 17 or 
fastening bars in which the plug of the vacuum tube in injected or 
attached by its edge so as to be fastened to the part 15 and enable it to 
be released and withdrawn and completely released after use (placing of 
the tabs 152, 152 in the notches 162A), the needle being completely 
retracted in the tube at this moment. 
The manoeuvre is performed very simply; it is sufficient for the blood 
sampling tube to be rotated about itself as a result of being held in one 
hand, the other hand holding the sleeve; the user then draws on the tube 
so as to withdraw the needle and retract it. Finally, the disc is locked 
in its end-of-travel position, and, as a result of greater stress being 
exerted, the tube is detached from the disc. 
Advantageously, the tabs 151, 152 project slightly relative to the outer 
surface of the sleeve; the amount by which they project depends on 
ergonomics. 
At the front the sleeve terminates in a tubular section 18 which protects 
the end of the section 141 of the needle projecting out of its aperture 13 
when the needle Is in the retracted position. This aperture 13 remains 
behind the sloping edge of the section 141 of the needle. 
At the rear, the sleeve has two gripping lugs 19 which are also 
diametrically opposite one another. 
FIGS. 3A and 3B show the needle 14 and the guiding and locking part 15 
outside the sleeve. FIG. 3B shows the particular shape of the tabs 151, 
152 and the position of the pins 17. 
In accordance with FIGS. 4 and 5 it is advantageous for the part 15 bearing 
the needle 14 to be completely locked in the first and second positions. 
For this purpose, the part 15 comprises projecting sections 153 (FIG. 4) 
for co-operating with sections 154, 155 in the form of tabs at the front 
and rear of the tube 11 in locations corresponding to the locking 
positions and projecting relative to the inner contour of the sleeve 11. 
When the sections 153 have passed between the section 154, 155, the part 
15 is pivoted as described above and this pivoting causes the sections 153 
to pass in front of the similar sections 154, 155. This bayonet-type 
fastening means completes the stage in which the device is locked in the 
position of use. The similar sections 154, 155 for locking it in the 
operating position and the retracted position are shown in FIG. 5. 
The sections 153 and sections 154, 155 can also cooperate directly with one 
another in the manner of cams in so far as the shape of one of the 
sections 153 and/or 154, 155 is not exactly circular but widens out. There 
is thus a wedging or cam effect which stiffens the inverse rotational 
movement and preserves the locking effect either in the position of use or 
the retracted position. 
The variant of the front wall according to Fig. 6 corresponds to a sleeve 
118 which, on the interior, widens from the guide aperture 113, whilst, in 
the embodiment shown in FIG. 7, the sleeve 218 has a smaller drilling and 
a drilling with a larger diameter 218A, 218B in front of the guide 
aperture 213. 
In accordance with FIGS. 8A, 8B, 8C, the guiding and locking disc 115 
supporting the needle 14 (141, 142) has indentations 116 so as to enable 
the two tongues 117 constituting the locking tabs to be able to tilt 
backwards (arrow M) when a thrust is exerted in the direction of the arrow 
N by the tube 118 and its plug 119 on the tongues 117 so as to release the 
disc 115 in its front position. 
The top of the disc 115 and of the tongues 117 supports fastening members 
120 for example in the form of tips on which the plug 119 of the tube 118 
connects. 
FIGS. 9A, 9B show a variant 111 of the sleeve 11 in FIG. 1. In accordance 
with this variant the groove 162 is extended beyond its section 162A by an 
assembly groove 262 which opens out behind the open rear of the sleeve 
111; in order to enable the tabs 117 (FIG. 8B) to pass through, the lugs 
119 are also provided with cut-outs 120. Thus, in order for the device to 
be assembled, the disc and its needle are slid from behind into the 
sleeve. 
In a general manner, the various parts of the device have sufficient 
clearance between them such that the movements can be performed easily 
whilst permitting excellent fastening both in the operating and in the 
retracted positions.