A precision proportional solenoid valve for ventilator

Abstract

The present invention provides a precision proportional solenoid valve for a ventilator, the proportional solenoid valve comprising: a valve seat for connecting a tool; an armature assembly, comprising an armature and a sealing block; a sleeve assembly, arranged against the valve seat, comprising a sleeve and an iron core; the armature performs the displacement in the chamber defined by the sleeve; a coil assembly arranged around and against the sleeve assembly, comprising a skeleton, a shell and a coil; an adjustment assembly, comprising an adjustment rod and a spring, for adjusting the preload force of the armature during operation; the two ends of the spring respectively abut against the adjustment rod and the spring hole in the armature; wherein a through hole is also provided in the armature, the through hole extending along the spring hole and opening on both sides of the sealing block, for improving the fluidity of the medium, so that the medium pressure in the proportional solenoid valve quickly reaches equilibrium. The precision proportional solenoid valve provided by the present invention has the advantages of fast response, precise flow control, and stable electromagnetic force.

Description

Technical Field

[0001] The present invention relates to the field of precise control of medical devices, and in particular to a precise proportional solenoid valve device applied to a ventilator. Background Art

[0002] The ventilators used in hospital clinics and medical emergency treatment need to have an output flow rate of 180L / min, and a main control valve group with extremely short response cycles and accurate distribution and mixing functions. For a more advanced ventilator, if it meets the above prerequisites, it can provide patients with adequate ventilation and extremely comfortable breathing support according to a certain control algorithm.

[0003] In addition, the existing patent CN215780800U discloses a proportional solenoid valve structure for a ventilator, which controls the electromagnetic force on the armature by controlling the duty cycle of the coil current, thereby controlling the axial position of the armature to achieve the purpose of controlling the flow rate. However, the vent hole in the armature structure is a through hole on one side, which has poor air permeability, causing the armature to be stressed and unstable in movement, and is not easy to process. Summary of the invention

[0004] In view of the current status and existing problems of the above-mentioned prior art, an object of the present invention is to provide a proportional solenoid valve which can respond quickly, control flow accurately and has stable electromagnetic force.

[0005] Specifically, in order to achieve the above purpose, the technical solution of the present invention is:

[0006] A precision proportional solenoid valve for a ventilator, the proportional solenoid valve comprising:

[0007] A valve seat, used for connecting to the tooling, the valve seat being provided with an air inlet passage and an air outlet passage in fluid communication;

[0008] An armature assembly, comprising an armature and a sealing block, wherein the sealing block is fixed to the end of the armature; the armature is displaced to drive the sealing block to realize on-off control between the air inlet channel and the air outlet channel;

[0009] A sleeve assembly is arranged against the valve seat, comprising a sleeve and an iron core; the armature is displaced in the chamber defined by the sleeve; wherein the iron core is assembled to the side of the sleeve away from the valve seat, and a magnetic isolation sheet is installed on the surface of the iron core facing the armature, for eliminating the excessive electromagnetic force of the armature and the iron core;

[0010] A coil assembly arranged around and against the sleeve assembly comprises a frame, a shell and a coil; the frame is arranged against the sleeve assembly, the coil is arranged around the frame to provide the armature with a magnetic field required for displacement, the shell wraps the frame and the coil and is connected to the lower end surface of the sleeve to achieve the overall connection of the device; an adjustment assembly comprises an adjustment rod (screw) and a spring for adjusting the preload force of the armature during operation; the adjustment rod is located in a cavity in the middle of the core and is fitted into the thread on the inner surface of the core, and both ends of the spiral spring are ground flat and respectively against the adjustment rod and the spring hole in the armature;

[0011] Wherein, the armature is also provided with a through hole, which extends along the spring hole and opens at both sides of the sealing block respectively, so as to improve the fluidity of the medium and enable the medium pressure in the proportional solenoid valve to quickly reach equilibrium.

[0012] Furthermore, the sleeve is composed of an upper sleeve, a magnetic isolation ring and a lower sleeve in sequence; the inner side length of the magnetic isolation ring is smaller than the outer side length (i.e., the magnetic isolation angle is smaller than 90°), and one end of the inner side of the magnetic isolation ring is adjacent to the iron core, and the other end is exposed to the upper part of the armature. Preferably, the inner side of the magnetic isolation ring is adjacent to one end of the iron core and at least reaches the extension line of the magnetic isolation sheet. More preferably, the inner side length of the magnetic isolation ring is not less than 3mm (or, optionally, the length of the magnetic isolation ring is not less than 1 / 5 of the length of the armature), and the thickness is 0.5-1.5mm.

[0013] Furthermore, the side of the iron core facing the armature is provided with an edge extending / protruding toward the armature, thereby forming a basin-shaped opening toward the armature; wherein the magnetic isolation sheet is only provided on the "bottom" surface of the basin. On this basis, the combination of the magnetic isolation ring and the magnetic isolation sheet is conducive to guiding the magnetic circuit in the upper sleeve to enter the armature through the protruding edge between the two, thereby improving the performance of the solenoid valve.

[0014] Furthermore, the armature assembly also includes a guide sleeve, which is installed in a corresponding groove on the outer surface of the armature and is used to abut against the sleeve to guide the armature to slide in the sleeve. The guide sleeve has an oblique opening to facilitate installation and subsequent maintenance.

[0015] Furthermore, the valve seat is connected to the lower casing by bolts, and the valve seat is provided with an air inlet sealing ring and an air outlet sealing ring on the surface connected to the tooling to achieve medium circulation and sealing.

[0016] Furthermore, the lead wire of the coil is led out from the distal opening of the shell.

[0017] Furthermore, the proportional solenoid valve also includes a hexagonal thin nut for cooperating with the external thread at the distal end of the iron core, and the outer shell of the coil assembly is pressed onto the sleeve by tightening.

[0018] Furthermore, the diameter of the through hole is smaller than the diameter of the spring, and the through hole has a Y-shaped cross section along the spring hole in the armature.

[0019] The beneficial effects of the present invention are:

[0020] Compared with the prior art, the air vent of the armature is a combination of inclined holes on both sides and a hole in the middle. The medium has better fluidity, balanced pressure, more stable armature movement, and improved instantaneous response performance of the solenoid valve. The guide sleeve adopts an oblique opening structure and can be directly installed, making later maintenance simple and convenient. The magnetic isolation ring can change the magnetic circuit in the sleeve and merge it with the magnetic circuit in the armature, thereby increasing the electromagnetic force of the armature and the working stroke of the armature. A magnetic isolation plate is provided on the lower surface of the static iron core to avoid the difficulty of closing the armature due to the large electromagnetic force after attraction, thereby causing a large flow hysteresis. It can effectively avoid the influence of the large residual magnetism after attraction on the reliability of the armature, which is beneficial to increase the service life of the armature. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The present invention is a structural schematic diagram of a precision proportional valve for a ventilator.

[0022] Figure 2 yes Figure 1 An enlarged view of part A of a precision proportional valve used in a ventilator.

[0023] Among them: hexagonal thin nut 1, shell 21, frame 22, coil 23, adjustment rod 31, spring 32, iron core 41, upper sleeve 42, magnetic isolation ring 43, lower sleeve 44, magnetic isolation sheet 45, armature 51, guide sleeve 52, sealing block 53, valve seat 6. DETAILED DESCRIPTION

[0024] The "easy-to-precise proportional solenoid valve for a ventilator" of the present invention is further described below in conjunction with the accompanying drawings. The accompanying drawings show preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly and comprehensively understood.

[0025] like Figure 1 to Figure 2 As shown, a precision control proportional valve device for a ventilator is provided, wherein a coil 23 is provided between the frame 22 and the housing 21, and a lead wire is led out from an opening at the upper end of the housing 21, and the coil is connected to direct current, and the magnetic field strength generated by the coil is controlled by adjusting the current. The hexagonal thin nut 1 is screwed downwardly in cooperation with the external thread at the top of the iron core 41 to press the housing 21 and the frame 22 (through the chamfering that cooperates with the housing 21) to the upper surface of the lower sleeve 44.

[0026] The sleeve is composed of an upper sleeve 42, a magnetic isolation ring 43 and a lower sleeve 44 from top to bottom; both the upper and lower sleeves are made of magnetic conductive materials to facilitate the introduction of magnetic circuits. The iron core 41 is assembled on the upper part of the sleeve, and the lower end transverse end surface of the lower sleeve 44 is matched with the valve seat 6 and connected by bolts. The upper sleeve 42 is adjacent to the iron core 41. The magnetic isolation ring 43 has an (equilateral) trapezoidal cross-section that is wide outside and narrow inside (see Figure 2 As shown in FIG. 4 , the length of the outer edge 43b is greater than that of the inner edge 43a. A portion of the inner edge 43a is adjacent to the iron core 41, and a portion thereof extends downward beyond the iron core 41 and is exposed to the armature 51, and its length is preferably not less than 1 / 5 of the length of the armature; the upper end of the inner edge 43a is level with the magnetic isolation plate 45, or higher than the magnetic isolation plate 45.

[0027] The lower end of the iron core 41 is a basin-shaped cross section, with a protruding "basin edge" (preferably a right-angle trapezoidal cross section) at the edge, and the protruding edge is a magnetic isolation means; a magnetic isolation sheet 45 (basically covering most of the surface of the iron core 41 at the basin bottom) is installed on the lower surface of the "basin bottom" of the iron core 41. The combined arrangement is conducive to guiding the magnetic path in the upper sleeve 42 into the armature 51 through the basin mouth, thereby improving the performance of the solenoid valve.

[0028] The sleeve, the iron core 41 and the valve seat 6 are assembled and connected to provide a chamber for the armature 51 to move, and the armature 51 moves up and down in the chamber. A sealing block 53 is installed at the lower end of the armature 51. The up and down movement of the armature 51 drives the sealing block 53 to contact and separate with the air inlet of the air inlet passage of the valve seat 6, thereby controlling the opening and closing of the air inlet. The armature 51 is slotted and installed with a guide sleeve 52 to guide the armature 51 to slide up and down in the sleeve. A hole is dug under the spring in the armature 51, and the inclined holes on both sides are connected to improve the fluidity of the medium, so that the medium pressure in the valve quickly reaches equilibrium and the armature movement is more stable.

[0029] The adjusting rod 31 is installed into the iron core 41 (the inner wall of which has a matching inner thread) through a thread, and forms an adjusting assembly with the spiral spring 32 with flat ends, which is used to adjust the preload force of the armature 51 during operation.

[0030] The valve seat 6 is connected to the lower casing 44 by bolts, and two O-rings are installed at the bottom to achieve the circulation of the medium.

[0031] The present invention belongs to a normally closed precision controlled proportional solenoid valve. The preload force of the spring 32 can be controlled by adjusting the screw to adapt to the state of keeping the valve (air inlet) closed at different air pressures. When the coil 23 is energized, the magnetic circuit enters the armature 51 from the iron core 41, and the magnetic circuit in the upper sleeve 42 bypasses the magnetic isolation ring 43 and enters the armature 51. The combined action of the two magnetic circuits can generate a constant electromagnetic force on the armature 51 within a certain stroke, thereby making the movement of the armature 51 more stable; when the combined force of the electromagnetic force and the inlet medium pressure exceeds the combined force of the preload force of the spring 32 and the friction force of the guide sleeve 52, the valve opens and stays at a force balance position; by adjusting the current of the coil, the armature can stay at different positions, thereby performing stepless regulation to control the flow output.

[0032] It should be understood that the directional indications such as "left", "right", "upper", and "lower" described herein are divided according to the directions of the devices shown in the figures. It should be understood that in the scheme of the present invention, the positions such as left, right, upper, and lower are interchangeable and do not constitute a substantial limitation to the scheme.

[0033] The examples described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the design concept of the present invention, any simple modifications, equivalent changes and modifications made to the technical solution of the present invention are still within the scope of the solution of the present invention.

Claims

1. A precision proportional solenoid valve for a ventilator, characterized in that: The proportional solenoid valve comprises: A valve seat, used for connecting the tooling, the valve seat being provided with an air inlet passage and an air outlet passage in fluid communication; An armature assembly, comprising an armature and a sealing block; the armature is displaced to drive the sealing block to realize on-off control between the air inlet channel and the air outlet channel; A sleeve assembly is arranged against the valve seat, comprising a sleeve and an iron core; the armature is displaced in the chamber defined by the sleeve; wherein the iron core is assembled to the side of the sleeve away from the valve seat, and a magnetic isolation sheet is installed on the surface of the iron core facing the armature, for eliminating the excessive electromagnetic force of the armature and the iron core; The coil assembly is arranged around and against the sleeve assembly, comprising a frame, a shell and a coil; the frame is arranged against the sleeve assembly, the coil is arranged around the frame to provide the armature with a magnetic field required for displacement, the shell wraps the frame and the coil and is connected to the sleeve to achieve the overall connection of the device; An adjustment assembly, comprising an adjustment rod and a spring, for adjusting the preload force of the armature during operation; two ends of the spring respectively abut against the adjustment rod and the spring hole in the armature; Wherein, the armature is also provided with a through hole, which extends along the spring hole and opens on both sides of the sealing block, and is used to improve the fluidity of the medium so that the medium pressure in the proportional solenoid valve can quickly reach equilibrium; The sleeve is composed of an upper sleeve, a magnetic isolation ring and a lower sleeve in sequence; the inner side length of the magnetic isolation ring is smaller than the outer side length, one end of the inner side of the magnetic isolation ring is adjacent to the iron core, and the other end is exposed to the upper part of the armature; the side of the iron core facing the armature is provided with an edge extending toward the armature, thereby forming a basin shape facing the armature; the inner side of the magnetic isolation ring is adjacent to one end of the iron core and at least reaches the extension line of the magnetic isolation plate; the inner side length of the magnetic isolation ring is not less than 3mm, and the thickness is 0.5-1.5mm; the diameter of the through hole is smaller than the diameter of the spring, and the through hole has a Y-shaped cross-section in the armature along the spring hole.

2. The precision proportional solenoid valve for a ventilator according to claim 1, characterized in that: The armature assembly also includes a guide sleeve, which is installed in a corresponding groove on the outer surface of the armature and is used to abut against the sleeve to guide the armature to slide in the sleeve. The guide sleeve has an oblique opening to facilitate installation and subsequent maintenance.

3. The precision proportional solenoid valve for a ventilator according to claim 1, characterized in that: The valve seat is connected to the lower casing by bolts, and an air inlet sealing ring and an air outlet sealing ring are provided on the surface connected to the tooling to achieve medium circulation and sealing.

4. The precision proportional solenoid valve for a ventilator according to claim 1, characterized in that: The lead wire of the coil is led out from the opening at the far end of the shell.

5. The precision proportional solenoid valve for a ventilator according to any one of claims 1 to 4, characterized in that: The proportional solenoid valve also includes a hexagonal thin nut for cooperating with the external thread at the far end of the iron core to compress the coil assembly.

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