KR20050052377A - Diaphragm pump - Google Patents

Abstract

The diaphragm type pump includes a diaphragm, a diaphragm case, and a drive body. The diaphragm has a center point and an outer periphery. The diaphragm case supports the diaphragm at its outer edge to form the pump chamber of the diaphragm case. The drive body has a diaphragm at its center point. As the driving body reciprocates, the diaphragm deforms to suck the fluid into the pump chamber and discharge the fluid to the outside of the pump chamber. The drive body includes a fitting portion and a flange portion. The fitting portion mounts the diaphragm and has a first side in contact with the diaphragm. The flange portion is formed outside the fitting portion. This flange portion has a second face which contacts the diaphragm when the diaphragm deforms to the pump chamber side. The second face has a first convex face region formed continuously with the first face.

Description

Diaphragm type pump {DIAPHRAGM PUMP}

The present invention relates to a diaphragm pump.

Japanese Laid-Open Patent Publication No. 7-14179 discloses a diaphragm type pump. As shown in FIG. 3, the outer peripheral portion 92a of the diaphragm 92 is supported by the fixing surface (bonding surface) 91a of the diaphragm case 91. The diaphragm case 91 and the diaphragm 92 form a pump chamber 93 in the diaphragm case 91. In the center of the diaphragm 92, a drive body (rod) 94 reciprocally driven by a drive source (not shown) such as an electric motor is mounted. When the diaphragm 92 deforms (displaces) by the reciprocating motion of the drive body 94, the volume of the pump chamber 93 increases and decreases, and the fluid flows into the pump chamber 93, and the fluid from the pump chamber 93 is changed. To discharge.

In the diaphragm-type pump, when the pressure in the pump chamber 93 increases during the discharge stroke, the portion of the diaphragm 92 in contact with the drive body 94 is supported by the drive body 94, while the drive body 94 The outer side of the diaphragm 92 which is not in contact with) is not directly supported by the drive body 94 and generally expands to the opposite side of the pump chamber 93. Even at the end of the discharge stroke, since the volume of the pump chamber 93 cannot be sufficiently reduced, the fluid remaining in the pump chamber 93 without being discharged from the pump chamber 93 increases, resulting in a decrease in the pump efficiency of the diaphragm pump. do.

However, in the diaphragm-type pump, the drive body 94 includes a fitting member 95 on which the diaphragm 92 is mounted, and a flange portion 96 formed outside the fitting portion 95. have. The flange portion 96 comes into contact with the diaphragm 92 when the diaphragm 92 deforms toward the pump chamber 93 so that the outer side of the diaphragm 92 expands toward the opposite side of the pump chamber 93 during discharge stroke. prevent.

  However, in the drive body 94 of the diaphragm-type pump shown in FIG. 3, the contact surface 95a of the fitting portion 95 in contact with the diaphragm 92 of the flange portion 96 is in contact with the diaphragm 92. Since it is not formed continuously with the contact surface 96a, the boundary part between the said contact surfaces 95a and 96a becomes angled. Therefore, the deformed diaphragm 92 at the discharge stroke comes into contact with the angular boundary at an angle of deflection, thereby degrading the durability of the diaphragm 92.

 An object of the present invention is to provide a diaphragm-type pump that can maintain the efficiency of a pump and improve the durability of the diaphragm.

The present invention provides the following features. The diaphragm type pump is provided with a diaphragm, a diaphragm case, and a drive body. The diaphragm has a center point and an outer periphery. The diaphragm case supports the diaphragm at the outer periphery of the diaphragm to form a pump chamber in the diaphragm case. The drive body holds the diaphragm at the center point of the diaphragm. As the driving body reciprocates, the diaphragm deforms, causing the fluid to flow into the pump chamber and to discharge the fluid out of the pump chamber. The drive body includes a fitting portion and a flange portion. The fitting portion has a first contact surface for mounting the diaphragm and making contact with the diaphragm. The flange portion is formed outside the fitting portion. This flange portion has a second contact surface which contacts the diaphragm when the diaphragm deforms toward the pump chamber. The second contact surface of the flange portion has a first convex surface that is formed continuously with the first contact surface of the fitting portion.

Other aspects and advantages of the present invention will become apparent from the following description which sets forth the principles of the invention in an embodiment manner with reference to the accompanying drawings.

Features of the invention, which are considered novel, are described in detail in the appended claims. The present invention and its objects and advantages will be very well understood by reference to the following description of the preferred embodiments in conjunction with the accompanying drawings.

Hereinafter, a diaphragm pump according to a preferred embodiment of the present invention will be described with reference to FIG. 1. In this preferred embodiment, the diaphragm pump is suitable for gas supply.

1 shows a cross-sectional view of a diaphragm pump. As shown in FIG. 1, the diaphragm-type pump has a diaphragm case 10, and the diaphragm case 10 includes a block 11, a circular tension plate 12 fixedly bonded to the block 11, And a main body case 13 in which the block 11 and the tension plate 12 are accommodated. The main body case 13 is in the form of a cylindrical cover, and as shown in FIG. 1, its cover portion is located on the upper side. The block 11 and the tension plate 12 are housed in the main body case 13 so that the block 11 is located on the cover side.

In the said block 11, the recessed part 11a is formed in the cross section by the tension plate 12 side. This recessed part 11a is closed by the diaphragm 14 interposed between the block 11 and the tension plate 12, and forms the pump chamber 15. The diaphragm 14 is metal and has a circular shape. The block 11 and the tension plate 12 are formed at the junction of the convex 11 and the tension plate 12, that is, the fixed surface 31 of the block 11 and the tension plate facing the fixed surface 31 ( The diaphragm 14 is deformably supported (displaced) by holding the annular region of the outer periphery 14a of the diaphragm 14 between the fixed surface 36 of 12.

The main body case 13 is formed with a suction passage 17 to which an external low pressure pipe (not shown) is connected, and a discharge passage 18 to which an external high pressure pipe (not shown) is connected. In the center part of the block 11, the suction port 25 which connects the pump chamber 15 and the suction passage 17, and the discharge port 26 which connects the pump chamber 15 and the discharge passage 18 are formed. A suction valve 21 in the form of a reed valve is formed between the suction port 25 of the block 11 and the suction passage 17 of the main body case 13. A discharge valve 22 in the form of a reed valve is formed between the discharge port 26 of the block 11 and the discharge passage 18 of the body case 13.

The diaphragm 14 is connected with a drive device 24 for driving the diaphragm 14. The drive device 24 is provided with a rod 45 that functions as a drive body driven to reciprocate by a drive source (not shown) such as an electric motor. The rod 45 is provided with a fitting portion 46 disposed outside the pump chamber 15 to mount the diaphragm 14 and a fixing portion 47 disposed inside the pump chamber 15 and fixed to the fitting portion 46. In between, the diaphragm 14 is hold | maintained at the center part. Therefore, when the rod 45 reciprocates, the diaphragm 14 deforms (displaces) and increases or decreases the volume of the pump chamber 15.

In particular, when the rod 45 is moved in the direction away from the pump chamber 15 (downward in FIG. 1), the diaphragm 14 deforms toward the opposite side of the pump chamber 15 to increase the volume of the pump chamber 15. . In the suction process in which the diaphragm 14 deforms toward the opposite side of the pump chamber 15, the suction valve 21 is pushed open to inject gas into the pump chamber 15 from the suction passage 17. On the contrary, when the rod 45 is moved to the pump chamber 15 side (upward in FIG. 1), the diaphragm 14 deforms toward the pump chamber 15 to reduce the volume of the pump chamber 15. In the discharge process in which the diaphragm 14 deforms toward the pump chamber 15, the gas in the pump chamber 15 is pushed open to discharge the discharge valve 22 and discharged to the discharge passage 18.

The rod 45 is provided with a fitting portion 46 and a circular flange portion 49 outside the fitting portion 46. The flange portion 49 contacts the diaphragm 14 when the diaphragm 14 deforms toward the pump chamber 15 so that the outer portion of the diaphragm 14 expands toward the opposite side of the pump chamber 15 during the discharge stroke. Prevents. Since the volume of the pump chamber 15 can be sufficiently reduced even at the end of the discharge stroke, the fluid remaining in the pump chamber 15 without being discharged from the pump chamber 15 is reduced, so that the pump efficiency of the diaphragm-type pump can be improved. have.

The contact surface 49a of the flange portion 49 in contact with the diaphragm 14 is a convex that is continuously formed on the contact surface 46a (plane) of the fitting portion 46 in contact with the diaphragm 14 and does not form an angle. The surface area 51 is provided. Therefore, when the diaphragm 14 deforms toward the pump chamber 15, the diaphragm 14 is located near the boundary between the contact surface 46a of the fitting portion 46 and the contact surface 49a of the flange portion 49. Even if it contacts, since the convex surface area | region 51 does not have a bending angle, the durability of the diaphragm 14 can be improved.

The contact surface 49a of the flange portion 49 is provided with a concave surface region 52 in addition to the convex surface region 51 described above. The convex surface area | region 51 comes into contact with the diaphragm 14 in the convex surface area | region 51 part vicinity of the fitting part 46 in an annular area. The concave region 52 is formed continuously with the convex region 51, and comes into contact with the diaphragm 14 at the concave region 52 region near the outer periphery 14a in the annular region.

As shown in Fig. 2, when the contact surface 49a of the flange portion 49 is formed only of the convex surface region, when the diaphragm 14 deforms toward the pump chamber 15 with a relatively large radius of curvature, The diaphragm 14 site | part of the peripheral part 14a is supported by the contact surface 49a of the flange part 49 so that this diaphragm 14 site | part may be interposed between the contact surface 49a and the fixed surface 31. As shown in FIG. It will be bent at a relatively large radius of curvature at the portion of the diaphragm 14 that is not. In the diaphragm 14 shown by the dashed-dotted line in FIG. 2, the diaphragm 14 part is shown by the arrow "M".

However, in the present embodiment, when the diaphragm 14 deforms toward the pump chamber 15 with a relatively large radius of curvature, the diaphragm 14 portion near the outer periphery 14a is the contact surface of the flange 49. 49a) (or the concave surface 52) is bent, i.e., the diaphragm 14 portion is in contact with the contact surface 49a and the fixed surface in a state where the diaphragm 14 portion is supported by the contact surface 49a. It is bent so that it may interpose with (31). With such a configuration, the diaphragm 14 is prevented from bending at a relatively large radius of curvature at a portion which is not supported by the contact surface 49a of the flange portion 49, so that the durability of the diaphragm 14 can be improved.

In the contact surface 49a of the flange portion 49, the curvature of the convex surface area 51 and the curvature of the concave surface area 52 are the same. More specifically, when viewed in a plane (i.e., the ground in FIG. 1) extending perpendicularly to the diaphragm 14 in the flat position and passing through the center point P of the diaphragm 14, The radius of curvature R1 of the curve X1 and the radius of curvature R2 of the curve X2 of the concave surface area 52 are the same.

Therefore, when the diaphragm 14 is deformed into a relatively large radius of curvature toward the pump chamber 15, the portion of the diaphragm 14 contacting the convex surface area 51 or the concave surface area 52 of the flange portion 49 is It is prevented from bending with a radius of curvature larger than other parts of the diaphragm 14, so that the stress caused by the bending moment is applied unevenly to the diaphragm 14 in contact with the contact surface 49a of the flange portion 49. Is prevented. Thus, the durability of the diaphragm 14 is further improved.

The block 11 forms a saving recess 48 in the center of the inner surface of the pump chamber 15. The clearance recess 48 is a rod 45 when the diaphragm 14 deformed to the pump chamber 15 side is located at a top dead center which minimizes the volume of the pump chamber 15 (the state shown by the dashed-dotted line in FIG. 1). ) Is for accommodating the fixing part 47 for fixing. The inner surface of the pump chamber 15 of the block 11 other than the clearance recess 48 forms a regulating surface 32 which defines the deformation limit of the diaphragm 14 on the top dead center side. That is, when the diaphragm 14 deformed to the pump chamber 15 side is located in a top dead center, the surface of the diaphragm 14 which opposes the pump chamber 15 will contact the regulating surface 32, and the diaphragm 14 will It is no longer elastically deformed.

The restricting surface 32 has a shape that coincides with the contact surface 49a of the flange portion 49. Therefore, with the diaphragm 14 located at the top dead center, the diaphragm 14 is formed with the entire contact surface 49a of the rod 45 (flange portion 49) and the entirety of the regulating surface 32 of the block 11. It is substantially interposed between and the volume of the pump chamber 15 becomes substantially zero, further improving the pump efficiency of the diaphragm-type pump.

In particular, the restricting surface 32 includes a convex surface region 33 having a shape corresponding to the concave surface region 52 of the contact surface 49a of the flange portion 49, and a convex surface region of the contact surface 49a ( A concave surface area 34 in a shape consistent with 51). The convex surface area | region 33 is formed continuously and smoothly with this fixing surface 31 so that an angle may not be formed in the boundary part with the fixing surface 31. As shown in FIG. The convex surface area | region 33 supports the diaphragm 14 which exists in the deformation | transformation limit of the top dead center side in the convex surface area | region 33 site | part of the outer peripheral part 14a in an annular area | region. The concave region 34 is smoothly formed continuously with the convex region 33 so as not to form an angle at the boundary with the convex region 33. The concave region 34 supports the diaphragm 14 at the strain limit on the top dead center side at a portion of the concave region 34 near the center point P of the diaphragm 14 in the annular region.

Therefore, even if the diaphragm 14 is in the deformation limit on the top dead center side and has a shape coinciding with the restricting surface 32, the vicinity of the boundary between the fixed surface 31 and the restricting surface 32 and the convex surface region 33 And a bending angle is not formed near the boundary between the concave surface region 34 and the like, and plastic deformation of the diaphragm 14 due to bending is prevented, thereby preventing deterioration in durability of the diaphragm 14.

The curvatures of the convex region 33 and the concave region 34 are the same. The curvature of the convex region 33 and the concave region 34 is the same as the curvature of the convex region 51 and the concave region 52. More specifically, the radius of curvature R1, the curvature, when viewed in a plane (ie, the ground in FIG. 1) that extends perpendicularly to the diaphragm 14 in the flat position and also passes through the center point P of the diaphragm 14. The radius R2, the radius of curvature R3 of the curve X3 of the convex surface region 33 and the radius of curvature R4 of the curve X4 of the concave surface region 34 are the same.

Therefore, if the diaphragm 14 is at the deformation limit on the top dead center side, the diaphragm 14 interposed between the convex surface region 33 of the regulating surface 32 and the concave surface region 52 of the flange portion 49. ) Curvature of the portion and the curvature of the diaphragm 14 portion interposed between the concave region 34 of the regulating surface 32 and the convex surface region 51 of the flange 49 are prevented from being different. The stress caused by the bending moment is prevented from acting unevenly on the diaphragm 14 at the strain limit on the top dead center side. Therefore, the durability of the diaphragm 14 is further improved.

In addition, the following embodiments can also be implemented without departing from the spirit of the present invention.

As shown in Fig. 2, the contact surface 49a of the flange portion 49 of the rod 45 is formed only of the convex surface region. In addition, the restricting surface 32 of the diaphragm case 10 (or the block 11) is formed only in the concave surface area so as to be in a shape coinciding with the contact surface 49a of the flange portion 49 formed only in the convex surface area. .

In the preferred embodiment and other embodiments, the curvature of the convex surface area 51 and the curvature of the concave surface area 52 are different from each other at the contact surface 49a of the flange portion 49. In the preferred embodiment and another embodiment, the curvature of the convex surface region 33 and the curvature of the concave surface region 34 are different from each other in the restricting surface 32. In the case of combining the former and the other embodiments, if the curvature of the concave region 34 of the restricting surface 32 is the same as the curvature of the convex region 51 of the flange portion 49, the restricting surface ( If the curvature of the convex surface region 33 of 32 is equal to the curvature of the concave surface region 52 of the flange portion 49, the regulating surface 32 coincides with the contact surface 49a of the flange portion 49. It takes shape.

In the above embodiment, the diaphragm-type pump of the present invention is used for the diaphragm-type pump for handling gas, but the diaphragm-type pump of the present invention is not limited to the diaphragm-type pump but can also be used for the diaphragm-type pump for handling liquid. have.

Accordingly, while examples and embodiments of the present invention have been described, the present invention is not limited thereto, and the present invention may be modified without being limited only to the details.

The diaphragm pump of the present invention can maintain the efficiency of the pump at the same time and improve the durability of the diaphragm.

1 is a cross-sectional view showing a diaphragm pump according to a preferred embodiment of the present invention;

2 is a cross-sectional view showing a diaphragm pump according to another preferred embodiment of the present invention, and

3 is a cross-sectional view of a diaphragm-type pump of the prior art.

* Description of reference numerals for major parts of the drawings

10: diaphragm case 11: block

12: tension plate 13: body case

14 diaphragm 15 pump chamber

24: drive device 32: regulation surface

45: rod 46: fitting portion

49: flange portion

Claims (7)

A diaphragm having a center point and an outer periphery, A diaphragm case supporting the diaphragm at the outer edge to form a pump chamber therein; and A drive body having a diaphragm at the center point, As the driving body reciprocates, the diaphragm deforms to flow the fluid into the pump chamber and discharges the fluid to the outside of the pump chamber. A fitting portion having a diaphragm and having a first surface in contact with the diaphragm; A flange portion formed on an outer side of the fitting portion and having a second surface contacting the diaphragm when the diaphragm deforms toward the pump chamber side; And the second face of the flange portion has a first convex surface region continuously formed with the first face of the fitting portion. 2. The second surface of the flange portion has a first concave surface region in addition to the first convex surface region, the first convex surface region having a diaphragm at a portion of the first convex surface region near the fitting portion. And a first concave surface region continuously formed with the first convex surface region, the first concave surface region contacting the diaphragm at a first concave region region near the outer periphery of the diaphragm. Type pump. 3. The diaphragm pump according to claim 2, wherein the curvature of the first convex region and the curvature of the first concave region on the second side of the flange portion are the same. The diaphragm type according to claim 1, wherein the diaphragm case has a restricting surface that forms an inner surface of the pump chamber and has a shape coinciding with the second surface of the flange portion, thereby providing a deformation limit of the diaphragm on the pump chamber side. Pump. 5. The diaphragm case according to claim 4, wherein the diaphragm case has a fixing surface for supporting the diaphragm at its outer periphery, the regulating surface is formed continuously with the fixing surface, and the regulating surface is near the second peripheral portion of the diaphragm. A second convex surface region supporting the diaphragm at the convex surface region, and a second concave surface region continuously formed with the second convex surface region and supporting the diaphragm at the second concave region region near the center point of the diaphragm; Diaphragm type pump, characterized in that. 6. The diaphragm pump according to claim 5, wherein the curvature of the second convex surface region and the second concave surface region of the restricting surface of the diaphragm case is the same. 7. The second convex surface region of claim 6, wherein the second surface of the flange portion has a first concave surface region other than the first convex surface region, and the first convex surface region of the second surface is the first convex surface region near the fitting portion. The diaphragm is in contact with the diaphragm, the first concave region of the second face is continuously formed with the first convex surface region, and the first concave region is in contact with the diaphragm in the first concave region region near the outer periphery of the diaphragm. And the curvature of the first convex region and the first concave region on the second side of the flange portion and the curvature of the second convex region and the second concave region of the restricting surface are the same. .