MXPA99000866A

MXPA99000866A - Liquid flow regulator

Info

Publication number: MXPA99000866A
Application number: MXPA/A/1999/000866A
Authority: MX
Inventors: Bron Dan
Original assignee: Bron Dan
Priority date: 1996-07-24
Filing date: 1999-01-22
Publication date: 2000-06-05

Abstract

A liquid flow regulator is provided, which has a divided housing that includes an upper portion connectable to a source of liquid to be supplied, the upper portion having an inlet portion and a lower portion that is intertwined with the upper portion and having a control outlet orifice leading to the consumer of the liquid, an elastically deformable diaphragm disposed in the housing and defining with a lower surface of the upper portion of the housing a first chamber and with a lower surface of the lower portion of the housing, in which is made the exit control orifice, an exit control chamber and a tubular flow attenuator disposed in the housing, forming a flow path of the liquid between the first chamber and the control chamber, characterized in that the diaphragm thickness is at least equal to the distance between the diaphragm in the resting state 1, the orifice exit control

Description

LIQUID FLOW REGULATOR BACKGROUND OF THE INVENTION - 5 In the present invention it relates to a liquid flow regulator. In particular, the present invention is suitable for use as an adjustable speed flow regulator usable in an infusion set. WO 96/03166 (Baxter) discloses a fluid flow regulator provided with a housing and a flexible diaphragm clamped in the housing along its pre-trim, previously inclined so that in its rest state it adopts an arched shape, previously subjected to diaphragm stress towards the outlet, 5 thus reducing the sensitivity causing the diaphragm to lose its elastic properties, especially in the range essential for the improved control sensitivity, required for low speed flows, such as which are normally used for the intravenous administration of fluids. 0 In the patent of E.U.A. No. 5,421,363, an adjustable speed flow regulator is described with greatly increased accuracy and improved repeatability, with respect to flow regulators of the prior art. This flow regulator is suitable for operating at low drip speeds that reach, for example, 2 ml / hr, with a low pressure drop across the diaphragm, for example only 40 cm of water, in view of the pressure head restricted. The regulator works as a closed-loop, negative feedback control system. Due to the attenuating trajectory of the relatively long flow, associated with the system feedback portion, as well as due to other system time constants during its operation, it tends to become inaccurate, unstable and oscillate vigorously around its velocity. operant flow set.

BRIEF DESCRIPTION OF THE INVENTION It is therefore a broad object of the present invention to overcome the inconveniences of the regulators of flow previously described and others of the prior art and provide a flow regulator having enhanced control sensitivity. It is another object of the present invention to provide a flow regulator that has improved stability of the output flow. According to the present invention, there is thus provided a liquid flow regulator, comprising a divided housing that includes an upper portion connectable to a source of liquid to be supplied, said upper portion having an entry trade and a lower portion that is intertwined with said upper portion and having a control outlet orifice leading the liquid consumer, an elastically deformable diaphragm disposed in said housing and defining with a lower surface of said upper portion of the housing a first - 5 chamber, and with an upper surface of said lower portion of the housing in which said outlet control orifice is made, an outlet control chamber and a tubular flow attenuator disposed in said housing, forming a flow path of liquid between said first chamber and said control chamber, characterized in that the thickness of said diaphragm is at least equal to its service amplitude that is defined by the distance between said diaphragm in its rest state and said exit control orifice. In a preferred embodiment, the invention provides furthermore a liquid flow regulator, characterized in that said regulator is an adjustable speed regulator, said upper and lower housing portions being intertwined with each other, said tubular attenuator is interlocked rotatably with one of said portions of housing, but not rotatably in relation to the other portion, wherein the inner wall surface of said tubular attenuator defines, together with a housing portion, a system of attenuating flow conduits of said liquid, whose attenuating effect of the flow can vary to adjust the flow velocity of said liquid. The invention will now be described in connection with certain preferred embodiments with reference to the following illustrative figures, so that it can be more fully understood. With specific reference now to the figures in detail, it is emphasized that the features shown are by way of example and for purposes of "illustrative consideration of the preferred embodiments of the present invention only and are presented in the cause of providing the which is believed to be the most useful and easily understood description of the principles and conceptual aspects of the invention. Regarding this, it is not intended to show structural details of the invention as more detail than is necessary for a fundamental understanding of the invention, taken the description with the drawings making it apparent to those skilled in the art how various forms of the invention can be modalized in practice.

DESCRIPTION OF THE DRAWING Figure 1 is a partial cross-sectional view of a flow regulator according to a preferred embodiment of the present invention.

DESCRIPTION OF THE PREFERRED MODALITY A flow regulator of the present invention is shown in Figure 1, either of the in-line type or of the type adapted to be connectable to the liquid flow line or connectable to a bag or bottle of infusion liquids by means of a pointed nozzle or similar (not shown). The flow regulator shown is advantageously of an adjustable speed type, however, as will be readily understood later in this, the present invention is not limited to adjustable speed regulators and could be applied to constant velocity flow regulators of the same speed. way . Seen in the figure is a divided housing 2 having an upper half 4 in the form of an inverted cup and connectable to a bag or bottle of infusion liquid (not shown) by means of a duct 6. The lower surface 8 facing downwards from the upper half 4 is provided with an inlet hole 10 surrounded by an edge which, at least one tip, has a groove or notch 14 to allow air to escape from a drip chamber when the system is used together with a infusion equipment or similar. Accordingly, air will be vented through the first chamber and the inlet to the liquid source. The lower portion 16 of the housing of the divided housing 2 is snapped into a slot 17 appropriately in the substantially cylindrical wall of the upper portion 4 and has a degree of freedom in rotation relative to. that of the upper portion 4. The lower portion 16 has a neck portion 18 of reduced diameter and a stepped cavity 20 on its upper face. The lower part 22 of the cavity 20 is provided with a slightly elevated control hole 24 of diameter d. It is seen that the lower portion of the lower portion 16 of the housing has at least one rib 26 that serves as an index marker to indicate the degree of relative rotation (for an adjustable speed regulator) on a scale (not shown) provided in FIG. the upper portion 4. The control hole 24 leads to the outside of the portion "15" lower housing 16 through the tubular system 28. Freely seated on the step 30 in the cavity ^^ 20 above, there is seen an elastically deformable diaphragm 32 having a balloon thickness in which, with the lower surface 8 of the upper portion 4 of the The housing defines a first chamber 34 and with the lower part 22 of the cavity 20, a second outlet control chamber. 36. The liquid access to the exit control chamber 36 is through the path 40. A tubular flow attenuator 42 is placed by a sliding fit on the neck portion 18 of the lower portion 16 'of the housing. The attenuator 42 is advantageously made of an elastomer. Further details concerning the attenuator of flow 42 and the manner of its operation are described., in the patent of E.U.A. 5,421,363 and the teaching thereof is incorporated herein by reference. - 5 In order to improve the sensitivity and stability and reduce the vibrations of the diaphragm 32 during operation, thus causing deviations and oscillations in the output flow of the regulator, the width W of the diaphragms shall be equal to the service amplitude A of the diaphragm 32 in the exit control chamber 36, or greater than the same. This amplitude A is substantially the distance between the lower surface of the diaphragm 32 at rest and edge 44 that surrounds the outlet control orifice 24. Further improvement in stability is achieved. of the outflow and in the sensitivity of the regulation and control, when the effective or service D diameter of the ^^ diaphragm 32, equal to or greater than 20 times the diameter d of the output control hole 24. Also, although in the mode shown the attenuator is made with a labyrinth-shaped groove, such groove can also be made in one of the portions of the housing which together with the attenuator defines a flow attenuating path. It will be apparent to those skilled in the art that the The invention is not limited to the details of the preceding illustrated embodiments and that the present invention can be modalized in other specific forms without deviating from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by appended claims rather than by the foregoing description and all the changes contained within the meaning and range of the invention. equivalence of the claims are therefore intended to be encompassed in it.

Claims

NOVELTY OF THE INVENTION CLAIMS

1. - A liquid flow regulator, comprising: a separation housing (2) including an upper portion connectable to a source of liquid to be supplied, said upper portion (4) having an inlet (10) and a lower portion (16) that is intertwined with said upper portion and having a control outlet hole (24) leading to the liquid consumer; an elastically deformable diaphragm (32) disposed in said housing and defining with a lower surface of said upper portion of the housing a first chamber (34) and with a surface -15 above said lower portion of the housing, in which said outlet control hole (24) is made, a chamber ^^ of exit control (36), and a tubular flow attenuator (42) disposed in said housing, forming a liquid flow path between said first chamber (34) and said 20 control chamber (36); further characterized in that the thickness of said diaphragm (32) is at least equal to its service amplitude (A), being defined by the distance between said diaphragm in its rest state and said exit control orifice (24).

2. The liquid flow regulator according to claim 1, further characterized in that the service diameter of said diaphragm (32) is at least equal to 20 times the diameter (d) of said control output orifice. (24)

3. The liquid flow regulator according to claim 1, further characterized in that said regulator is an adjustable speed regulator, being in said upper and lower portions (4, 16) of the housing rotatably intertwined with each other, said attenuator tubular (42) is interlocked rotatably with one of said portions of the housing, but not rotatable relative to the other portion, wherein the inner surface of the wall of said tubular attenuator together with the housing portion defines a system of attenuating conduits of flow of said liquid, attenuating effect of the flow of the conduits that can be varied to adjust the flow velocity of said liquid.