FR2593069A1 - LIQUID INJECTOR, FOR EXAMPLE HYPODERMAL SYRINGE. - Google Patents

Abstract

An injector 1 comprises a shutter 3 acting as a limiter of the forward movement of a piston 2 and mounted so as to be movable longitudinally on the outer periphery of the piston. A projection 3b is provided on the shutter so as to be removably engaged in a groove 5 formed in the piston, and a maximum graduation scale 7a is also provided on the cylinder 4 at a position corresponding to the front face of the piston. , when the piston is brought to a position in which the rear surface of the cylinder abuts against the front face of the shutter. (CF DRAWING IN BOPI)

Description

1. The present invention relates to an improvement

  of a liquid injector, for example for a hypodermic syringe

  and, in general, a liquid injector

  can be used in various fields in which it is necessary

  to perform an injection operation.

  The liquid injectors of the prior art

  feel a graduated scale on the outside surface of a cylinder or piston so as to inject the quantity

  required fluid by referring to the reading of the scale.

  In a conventional injector of this type, it is tedious

  for the user to have to watch the graduation of the injection

  during each use. In addition, it is difficult

  to properly stop the piston at a predetermined position

  born from the scale of the injector so the amount

injected is often wrong.

  To avoid the disadvantages described above, it has been proposed so far many adjustable injectors. For example, a shutter is attached to the piston of the injector, the liquid being injected by displacement of the piston until the shutter reaches the upper end of the cylinder.

  However, although an injector of this type

  adjust the amount of injectable fluid accurately

  its simplicity, it can not control the quantity of liquid

  to be introduced accurately, which causes complications when injecting the same amount

of liquid in several places.

  Thus, the injectors of the prior art are

  reading a scale carried by the piston or cylinder

  when you have to introduce a liquid. In other words,

  Until now, no injector has been proposed to introduce

  re a liquid in a precise and simple way without having to read

scale.

  It is tedious for the user, especially

  for a blind user to have to read the scale of the injector during use whenever

  have confirmation of the amount of liquid injected.

  The present invention relates to an injector

  to introduce precisely a specific quantity of

  liquid without the need to proceed with the

reading a scale.

  According to the present invention, provision is made

  jector having a shutter acting as a movement limiter

  advance of a piston and mounted on the perimeter

  outermost piston of the piston so as to be movable in a longitudinal direction, wherein a projection is provided on the shutter so as to be removably connected to a groove in the piston, and a scale at maximum graduation is provided on a cylinder at a location corresponding to the front face of the piston, when the piston moves to a position where the rear surface

  of the cylinder abuts against the front face of a rim

shutter.

  In the injector, each connection distance provided on the outer surface of the piston grooves

  can be in accordance with the graduations of the scale.

  3. The present invention will be well understood when

  of the following description made in connection with the drawings

  attached in which: Figure 1 shows an injector in the case where the liquid is filled up to a quantity corresponding to the maximum scale graduation; Figure 2 shows the injector in the case

  o the liquid is filled to a specific quantity

  smaller than the upper limit of the scale which corresponds to a position where the projection of

  the shutter is placed in a groove spaced from the groove

re the highest;

  FIG. 3 represents an injector before the in-

  troduction of a liquid in the cylinder; and FIG. 4 represents an injector in the case where a liquid is introduced to a level exceeding

upper limit of the scale.

  An injector according to the present invention will now be described in detail. The injector 1 is composed of a piston 2, a shutter 3 and a cylinder 4. The piston 2 is provided at its upper end with a gasket 2a which can move freely along the inner surface of the piston.

  cylinder 4 being closely contiguous thereto. At the

  2 of the piston 2, a rod 2b is formed, which has engagement grooves 5 spaced from each other following

  predetermined intervals and connected to a longitudinal groove

  6. At the rearmost end of the piston 2, a

  flange 2c is formed to facilitate operations.

  The shutter 3 has a cylindrical portion 3a, whose outside diameter is greater than the inside diameter of the cylinder 4, a projection 3b at the inside edge of its upper open end, which is connected to the grooves 5

  piston rod 2b, and a rim 3c at the rear end

  re of the cylindrical portion 3a. The shutter 3 is mounted on the outer periphery of the rod 2b of the piston 2, which can move in the axial direction and be rotated in the circumferential direction of the piston.

  shutter 3 movement occurs by animating a

  the piston or shutter in the direction

  circumferential movement of the piston so that the projection 3b

  the shutter can be in the longitudinal groove

  nal 6, then moving the shutter freely along the

the longitudinal groove 6.

  In some embodiments where no longitudinal groove 6 is provided, the projection 3b may

  be made of plastic resin-dee elastically deformable.

  When the shutter 3 is moved relative to

  cylinder in the longitudinal direction, the projection 3b comes

  periodically in contact with each groove 5 to produce

  a dry sound. Therefore, this dry noise allows the user to

  sator, especially to a blind person, to know that she is

  the position of the shutter 3 without having to look at the

the reach by the cylinder 4.

  The cylinder 4 has a cylindrical portion 4a into which a liquid 8, a

  needle 4b at the top of part 4a, and a part to

  edge 4c which can be received on the front face of the closure

  3, being mounted at the rear end of the cy-

  lindrique 4a. On the outer surface of the portion 4a of the cylinder, a ladder 7 is provided in accordance with each of the intervals of the grooves 5 formed on the rod 2b

of the piston.

  Among the graduations of scale 7, the

  7a maximum duation corresponds to a position in which is the front end face of the lining 2a when the piston 2 is driven in a downward motion until

  that the front face of the shutter reaches the re-

  4c edge of the cylinder, insofar as the projection 3b of the shutter is maintained in the highest position of the

  grooves 5a. (See Figure 1)

  In a practical operation, the use of the injector of the present invention may be even more interesting if, for example, a sensation or a dry noise.

  different are obtained when the protrusion 3b of the obtura-

  contact with a specific part of the grooves.

  5, or if a very sharp distinction can be made.

  Always in connection with the drawings, we describe

  ra hereinafter an injection operation according to the present invention. Firstly, as shown in FIG. 3, the front face of the lining 2a is in contact with the bottom of the cylinder 4 by displacement of the piston 2 downwards, insofar as the shutter 3 is held in the part the highest of the piston 2 until the flanged portion 3c

  the shutter reaches the flange 2c of the piston.

  The liquid to be injected 8 is introduced completely

  in the cylinder 4 when the piston 2 is partially

  extracted from the back until the

  of the filling 2a come on the maximum graduation 7a

  of the cylinder. Then, we move the projection 3b of the obtura-

  3 and immobilizes it on the rod 2b so that it can be adjusted

  the gap between the rear end surface of the cylinder and the front end face of the shutter 3 for some

amount of liquid to use.

  Figure 4 shows the injector in the case

  of a maximum introduction of liquid into the cylinder, this

  the latter corresponding to the maximum graduation 7a of the scale, and the projection 3b being immobilized at the highest part

grooves 5.

  If we do not need the maximum quantity of the liquid 8, we can place the projection 3b of the shutter 3 at a position n corresponding to a graduation n of the scale.

  (n is an integer) from the maximum position.

  Thus, we simply advance the piston 2 in the

  cylinder 4 until the front face of the shutter 3 bu-

  against the rear end of the rim 4c of the cylinder, this

  which makes it possible to maintain in this cylinder a certain quantity

  liquidity. If the user intends to fill the ladder up to the maximum scale of 6. as shown in Figure 4, he moves the piston 2 forward until the front face of the trim 2a the position

  of the maximum graduation 7a, as shown in FIG.

  re 1, after complete introduction of the liquid into the cylinder, o extraction from the cylinder of the excess liquid of

  to maintain the required predetermined amount of liquid

  of. Alternatively, if the user wishes to perform

  a filling with a quantity corresponding to the graduation

  tion n of the scale, it can advance the piston 2 until the lower face of the flange 2c piston abuts

  against the front face of the flange 3c of the shutter, the posi-

  by placing the projection 3b on the

  duation n, so that the lining can be advanced correctly to the position corresponding to the graduation n. The filling in liquid is thus completed in the preceding manner.

  At the completion of the liquid filling, this

  it can be injected by advancing the piston after releasing and moving the shutter towards the rear of the

  adjustment position to the underside of the collar-

2c of the piston.

  The liquid can also be injected in an amount corresponding to each division, this amount remaining uniform. In this case, the shutter is actuated as an organ for injecting the liquid, not only for

filling in liquid.

  The injector of the present invention having the construction just described has the advantage that it

  allows the user to easily and correctly

  the injection operation of a prescribed amount without having to confirm the extent of the extraction movement of the piston by looking at the scale that carries the piston or the cylinder. As explained above, the injector may also be of particular interest to a blind user if the shutter movement can produce a dry noise when moved longitudinally.

relative to the piston 2.

  The present invention is not limited to the embodiments which have just been described.

  is, on the contrary, susceptible of modifications and

  which will appear to the man of the art.

8.

Claims (2)

  1 - Injector comprising a shutter (3) acting as a limiter of the movement of advance of a piston   (2) and mounted on the outer peripheral part of the pis-   in order to be mobile in the longitudinal direction,   characterized in that a protrusion (3b) is provided in the obtura-   to be releasably engaged in a groove (5) in the piston, and in that a ladder with a maximum graduation (7a) is provided on a cylinder (4).   at a position corresponding to the front face of the piston when   that the piston is brought to a position in which the rear surface of the cylinder abuts against the front face shutter.   2 - Injector according to claim 1, wherein each engagement distance provided on the outer surface of the grooves (5) of the piston is in compliance   with the graduations of the scale (7).