JPH0524978U - Structure of diaphragm in air feeding device - Google Patents

Abstract

(57) [Abstract] [Purpose] To reduce the noise generated when a diaphragm provided in an air feeding device such as an air pump or a compressor reciprocates in response to an air feeding operation. [Structure] The peripheral portion 28b is the frame 3 of the air pump
2, 38 and the mounting member 2 on the central portion 28a.
2 is attached to the annular movable membrane region 28 of the diaphragm 28.
In c, the curved portion 48 is continuously formed over the entire circumference, and the projection 54 is integrally provided over the entire circumference on the diaphragm film surface 52 corresponding to the surface 50 of the mounting member. The curved portion and the projection form the diaphragm. The fluttering noise and the tapping noise, which are the main causes of noise generation, are reduced.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a structure of a diaphragm that defines a variable volume chamber that stores an air to be fed in an air feeding device such as an air pump or a compressor.

[0002]

[Prior Art]

 The diaphragm used in this type of air feeding device has a flat disk shape, the peripheral edge of which is fixed to the frame, and a mounting member is attached to the center of the diaphragm. It is connected to a driving body that reciprocates the diaphragm. Then, the diaphragm is deformed by the reciprocating motion from the driving body, and the air in the variable volume chamber is sequentially discharged from the chamber to supply the air. The diaphragm is made of elastically deformable rubber or synthetic resin.

[0003]

[Problems to be solved by the device]

 Noise is a problem during air feeding operation in which the diaphragm reciprocates. As the reciprocating motion speeded up, the noise also increased, and it was required to reduce the noise. It is considered that the main causes of the generated noise are roughly classified into the following two points. One is the sound that is caused by the diaphragm vibrating finely when the diaphragm is deformed due to the pressure fluctuation of the air in the variable volume chamber. The other one is a sound generated when the corresponding surface of the membrane of the diaphragm hits the mounting member attached to the central portion of the diaphragm (hereinafter referred to as a tapping sound). Therefore, it is considered necessary to reduce these beating sounds and beating sounds.

Therefore, an object of the present invention is to provide a structure of a diaphragm in which both the fluttering noise and the tapping noise, which are the main causes of noise, are minimized to reduce the noise of the diaphragm generated during the air feeding operation. To do.

[0005]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object of the present invention, the present invention comprises a variable volume chamber for containing air to be fed and a diaphragm for partitioning the chamber, and the peripheral portion of the diaphragm is fixed to a frame. Assuming an air feeding device such as an air pump or a compressor, in which a mounting member is attached to the central portion and is connected to a driving body that reciprocates the diaphragm through the mounting member, In the annular movable membrane area except for the peripheral portion fixed to the frame and the central portion where the mounting member is attached, a curved portion with a cross section along the radial direction curved in an arc shape is formed continuously over the entire circumference. The present invention proposes a structure of a diaphragm characterized in that a protrusion is integrally provided over the entire circumference on a film surface corresponding to the mounting member on the protruding side of the curved portion.

[0006]

[Action]

 According to the configuration of the present invention, the curved portion as described above is continuously formed over the entire circumference in the annular movable membrane region of the diaphragm, so that vibration of the membrane surface when the diaphragm is deformed is suppressed and the diaphragm flutters. Sound can be reduced, and by providing the above-mentioned projection integrally with the film surface corresponding to the mounting member over the entire circumference, the projection comes into contact with the surface of the diaphragm with respect to the mounting member. Contact with the diaphragm can be avoided, and the sound of the diaphragm striking can be reduced.

[0007]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an air pump as an air feeding device. 10 is a pump main body equipped with a motor 12, 14 is a drive shaft which is rotationally driven by the motor 12, and 16 is fixed on the drive shaft 14. An eccentric ring 22 for converting the rotational movement of the shaft 14 into a forward / backward movement along the axis XX direction to the connecting rod 20 via the bearing 18, and 22 is integrally attached to the free end of the connecting rod 20 by a bolt 24. It is an attachment member that is attached and cooperates with the retainer plate 26 to attach and fix the diaphragm 28. In a broad sense, the retainer plate 26 constitutes a part of the mounting member.

The diaphragm 28 is formed of a rubber material into a disk shape, and is fixed by a bolt 30 with the central portion 28 a being sandwiched between the mounting member 22 and the retainer plate 26, and the peripheral edge portion 28 b is on the pump body 10 side. The frame 32 and the frame 38 of the pump head 36, which is integrally attached to the main body 10 by the bolts 34, are sandwiched and fixed. A portion other than the central portion 28a and the peripheral portion 28b is defined as an annular movable film region 28c. The detailed structure of the diaphragm 28 will be described later with reference to FIGS. 2 and 3.

Reference numeral 40 denotes a pump chamber that constitutes a variable volume chamber, and a diaphragm 28 is located on one side of the pump chamber to partition the pump chamber 40. The pump chamber 40 communicates with an air outflow port 46 via a reed valve 42 and a flow passage 44 formed in the pump head 36. In FIG. 1, only one of the flow passage 44 and the air outlet / inlet port 46 is shown for inflow and outflow, but the other one is not shown in the drawing because it is behind it.

In the air pump having the above structure, when the pump is operated, the drive shaft 14 is rotated by the drive of the motor 12, and the connecting rod 20 is reciprocated with a stroke of a predetermined length via the eccentric ring 16 and the bearing 18. When transmitted, the mounting member 22 and the retainer plate 26 deform the annular movable membrane region 28c of the diaphragm 28 to reciprocate, causing a change in the volume of the pump chamber 40, thereby causing air as a pumping fluid to flow. It is pumped from the pump chamber 40 through the air outflow port 46.

2 and 3, in the annular movable membrane region 28c of the diaphragm 28, a cross section along the radial direction is curved in an arc shape toward the operating side 46 opposite to the pump chamber 40. A curved portion 48 is formed continuously over the entire circumference of the disk-shaped diaphragm 28. The shape of the curved portion 48 is more clearly shown when the diaphragm 28 is in the most contracted position as shown by the solid line in FIG. 2, and in the stroke end state shown by the chain line in the figure, the curved portion 48 is formed. Is stretched and deformed into a flat shape. Since the curved portion 48 is configured to project toward the pump chamber 40 side in view of the fact that the internal pressure of the pump chamber 40 acts as indicated by the arrow, there is a risk that it may be reversed by the internal pressure, which is not desirable, It is more desirable to have a projecting shape toward the operating side 46 as described above.

Further, in the annular movable membrane region 28 c of the diaphragm 28, a protrusion 54 is formed on the membrane surface 52 corresponding to the surface 50 of the mounting member 22 on the side where the curved portion 48 protrudes (actuation side 46). It is provided integrally over the entire circumference of 28. As shown in FIG. 3, the projection 54 has an annular projecting shape, but a discontinuous shape is also possible. Due to the provision of the projections 54, the rounded surface 50 of the peripheral edge of the mounting member 22 which comes into contact with and supports the diaphragm surface when the diaphragm 28 is deformed is a diaphragm of the corresponding diaphragm. Surface contact with the surface 52 is avoided, leaving a gap T between the surfaces 50, 52 as shown in FIG.

By forming the curved portion 48 of the diaphragm 28, the fluttering noise generated during the deformation operation of the diaphragm 28 is significantly reduced. This is because by forming the curved portion 48 on the diaphragm 28 in advance, the vibration of the film surface generated in the conventional flat surface shape is positively eliminated.

Further, by forming the protrusion 54 of the diaphragm 28, the tapping noise generated during the deformation operation of the diaphragm 28 is significantly reduced. As described above, this prevents the diaphragm membrane surface 52 from directly hitting the surface 50 of the mounting member 22 in the form of surface contact, and only the small area portion of the protrusion 54 contacts the surface 50. It is because it came to hit.

As described above, in the present invention, by providing both the curved portion 48 and the protrusion 54 in the annular movable film region 28c of the diaphragm 28, the flutter that is the main cause of noise generated when the diaphragm reciprocates. The sound and tapping sound are greatly reduced.

Although an air pump is disclosed as an air feeding device in the embodiments, the present invention can be applied to other devices such as a compressor. Further, although the diaphragm has a disk shape, a rectangular shape is also included in the present invention. Needless to say, the present invention is not limited to the embodiments.

[0017]

[Effect of the device]

 As described above, according to the present invention, both the curved portion and the protrusion are provided in the annular movable membrane region of the diaphragm, and one curved portion configuration is one of the main causes of noise generation. The fluttering noise is significantly reduced, and the other projection configuration also significantly reduces the tapping noise, which is one of the other main causes, so the overall noise generated from the diaphragm during operation is significantly reduced. Moreover, since the curved portion and the protrusion can be integrally formed at the same time when the diaphragm is formed, and the structure is not particularly complicated, a very high practical effect is achieved in achieving the purpose of noise reduction. It is a thing.

[Brief description of drawings]

FIG. 1 is an overall broken view of a main part of an air pump showing an embodiment of an air feeding device having a diaphragm according to the present invention.

FIG. 2 is an enlarged cross-sectional view of an essential part of FIG. 1 showing a detailed structure of a diaphragm according to the present invention.

FIG. 3 is a plan view of relevant parts showing the diaphragm shown in FIG. 2 in a state in which the diaphragm is viewed from the operating side and the mounting member is removed in order to show the planar shape of the diaphragm shown in FIG. 2;

[Explanation of symbols]

 10 Pump Main Body 22 Mounting Member 28 Diaphragm 28c Annular Movable Membrane Area 48 Curved Part

Claims (1)

[Scope of utility model registration request] 1. A variable volume chamber for accommodating air to be fed, and a diaphragm for partitioning the chamber, wherein a peripheral portion of the diaphragm is fixed to a frame, and a mounting member is attached to a central portion, In an air feeding device such as an air pump or a compressor, which is connected to a driving body that reciprocates the diaphragm through a mounting member,
In the annular movable membrane region excluding the peripheral portion fixed to the frame and the central portion to which the mounting member is attached, a curved portion whose cross section along the radial direction is curved in an arc shape is continuously formed over the entire circumference. At the same time, the structure of the diaphragm is characterized in that projections are integrally provided on the film surface corresponding to the mounting member on the projecting side of the curved portion over the entire circumference.