JP6677566B2 - Diaphragm pump - Google Patents

Description

  The present invention relates to a diaphragm pump used to supply compressed air to a blood pressure monitor or the like, for example.

  A conventional diaphragm pump of this type includes a cylindrical housing body having one end attached to a motor, a plate-like member or a lid member for holding parts attached to the other end of the housing body, and And a fixing structure for fixing the cover member and the lid member to the housing body. As this fixing structure, for example, a structure using a fixing member as described in Patent Document 1 or Patent Document 2, a structure using a locking piece as shown in FIGS. 4 and 5, and the like are known. ing.

  The diaphragm pump disclosed in Patent Literature 1 includes a cylindrical housing body having one end attached to a motor, a plurality of plate-like members for holding parts attached to the other end of the housing body, and a lid member. It has. The plurality of plate-shaped members and the lid member are connected to the other end of the housing body in a state where they are overlapped with each other, and are fixed to the cylindrical housing body by bolts as fixing members penetrating these members. I have.

  The diaphragm pump disclosed in Patent Literature 2 has a cylindrical housing main body having one end attached to a motor, a plate-like member for holding parts attached to the other end of the housing main body via a diaphragm, A lid member or the like is provided on the plate member. The diaphragm, the plate-shaped member, and the lid member are fixed to the housing body by being pressed against the housing body by a rod-shaped spring member as a fixing member in a state of being assembled to the housing body. The rod-shaped spring member sandwiches all these members from both sides in the axial direction in a state where the diaphragm and the plate-like member are sandwiched between the housing body and the lid member.

The diaphragm pump 1 shown in FIGS. 4 and 5 has a cylindrical housing body 3 having one end attached to a motor 2, a lid 4 attached to the other end of the housing body 3, and a housing body. 3 is provided with a fixing structure 5 for fixing the lid 4.
A first concave groove 6 extending from the other end (the upper end in FIG. 4) of the housing main body 3 toward the motor-side one end is formed in the outer peripheral portion of the housing main body 3. A projecting locking projection 7 and a second concave groove 8 extending from the first concave groove 6 to one end of the housing body 3 are formed.

The first concave groove 6 is formed to have a size capable of accommodating the arm 9 protruding from the lid 4. The arm 9 is formed in a plate shape having a hole 9a with which the locking projection 7 engages. The fixing structure 5 is constituted by the locking projections 7 and the arms 9.
The second concave groove 8 is formed to allow a part of a mold (not shown) for molding the locking projection 7 to pass through at the time of mold release.

JP-A-2004-11579 JP-A-2004-270494

  The fixing structures disclosed in Patent Literature 1 and Patent Literature 2 have a problem that a fixing member (a fixing bolt or a rod-shaped spring member) is required, which increases the manufacturing cost. In addition, the diaphragm pump 1 shown in FIGS. 4 and 5 does not require a fixing member, but has the following two problems.

  The first problem is that the first and second concave grooves 6 and 8 are formed in the housing body 3 and the arm 9 having the hole 9a is formed in the lid 4, so that the housing body 3 and the lid 4 The manufacturing cost of the metal mold for molding is increased. A second problem is that the noise is increased. It is considered that the reason why the noise is increased is that the thickness of the bottom of the first and second concave grooves 6, 8 is thinner than the other peripheral wall 3a of the housing main body 3. That is, it is considered that the sound leaks out of the housing main body 3 through the bottoms of the relatively thin first and second concave grooves 6 and 8.

  The present invention has been made in order to solve such a problem, and an object of the present invention is to provide a diaphragm pump that can reduce manufacturing cost and reduce noise.

In order to achieve this object, a diaphragm pump according to the present invention is formed in a tubular shape, a diaphragm mounting portion is provided therein, and a housing main body having one end mounted to a motor; A lid that fits into the opening and closes the opening, and is provided at a fitting portion between the housing main body and the lid, and moves the lid fitted to the housing main body in a removing direction. A restricting locking structure, a diaphragm sandwiched and held between the diaphragm mounting portion and the lid, and constituting a pump chamber between the lid and the lid; and a diaphragm provided on the lid and suctioned into the pump chamber. An intake passage that guides air through a valve, a discharge passage that is provided in the lid, and that discharges air from the pump chamber through a discharge valve; and a die that converts rotation of the motor into reciprocating motion. Transmitted to Fulham, and a driving mechanism for increasing or decreasing the volume of the pump chamber, the locking structure is projecting from the lid, said housing from the fitting surface to be fitted with the housing body in the cover body A convex portion protruding toward the main body, and a wall portion formed at a portion of the housing main body that fits with the lid, and configured to overlap the convex portion when viewed from an axial direction of the motor , wherein the convex portion is , On the fitting surface of the lid, projecting at positions spaced apart by a predetermined distance in a direction perpendicular to the fitting direction, respectively, one end of the wall portion on the motor side is provided A concave portion into which a part of the convex portion is engageable is formed, and a rounded portion is formed at the other end of the wall portion opposite to the motor, so that the concave portion of the wall portion and the rounded portion are formed. Overlaps with the fitting surface of the lid between In which the surface is formed.

According to the present invention, in the diaphragm pump, the convex portion may be formed in a hemispherical shape.

In the diaphragm pump according to the present invention, the diaphragm is attached to the diaphragm mounting portion of the housing main body, the lid is inserted into the opening of the housing main body, and the projection of the locking structure is locked to the wall portion, whereby the lid is closed. The body is fixed to the housing body. For this reason, the lid is fixed to the housing main body without using fixing members such as bolts and spring members.
Further, in this diaphragm pump, since the locking structure is provided at the fitting portion between the housing main body and the lid, a thin portion is not formed on the wall of the housing main body.
Therefore, according to the present invention, it is possible to provide a diaphragm pump that can reduce manufacturing costs and reduce noise.

It is a sectional view of a diaphragm pump concerning the present invention. It is sectional drawing which expands and shows a principal part. It is sectional drawing which shows other embodiment of a locking structure. It is a perspective view of the conventional diaphragm pump. FIG. 5 is a sectional view taken along line V-V of a locking portion in FIG. 4.

Hereinafter, an embodiment of the diaphragm pump according to the present invention will be described in detail with reference to FIGS.
The diaphragm pump 11 according to this embodiment operates by being driven by a motor 12, sucks air from an intake port 13 provided in the vicinity of the motor 12, discharges air from a discharge pipe 14 located at an upper end in FIG. Is what you do. Hereinafter, in describing the configuration of the diaphragm pump 11, for convenience, the end on the motor 12 side will be referred to as one end of the diaphragm pump 11, and the end on the discharge pipe 14 side will be referred to as the other end of the diaphragm pump 11. I do.

  The diaphragm pump 11 has a housing 15 in which one end is fixed to a motor 12 and accommodates functional components to be described later. The housing 15 has a cylindrical housing main body 16 whose one end is fitted to the motor 12, and a disc-shaped lid 17 which fits into the opening at the other end of the housing main body 16 and closes this opening. And is constituted by. The housing body 16 and the lid 17 are formed by molding a plastic material into a predetermined shape using a mold (not shown).

The above-mentioned discharge pipe 14 is integrally formed at the center of the lid 17 by integral molding. The lid 17 is fixed to the housing body 16 by the locking structure 21 according to the present invention. The locking structure 21 regulates the movement of the lid 17 fitted to the other end of the housing main body 16 in the removing direction (the direction opposite to the motor 12), which will be described later in detail.
The motor 12 has a configuration in which a rotating shaft 23 protrudes from one axial end of a cylindrical motor housing 22. The rotation shaft 23 is positioned on the same axis as the motor housing 22. A crank 24, which is one of the functional components of the diaphragm pump 11, is attached to a rotating shaft 23 of the motor 12 so as to rotate integrally therewith.

  The housing body 16 of the diaphragm pump 11 is fitted on the outer peripheral surface of the motor housing 22. For this reason, the housing main body 16 is positioned on the same axis as the rotation shaft 23. Although not shown, the housing main body 16 can be fixed to the motor housing 22 by, for example, engaging a locking hook provided on the housing main body 16 with an engaging hole of the motor housing 22.

The above-described intake port 13 is formed in a portion of the housing body 16 adjacent to the axial end surface 22a of the motor housing 22. The air inlet 13 is formed as a through-hole penetrating the peripheral wall 16 a of the housing body 16.
The functional components of the diaphragm pump 11 include the above-described crank 24, a driver 25 connected to the crank 24, a diaphragm 26 connected to the driver 25, and the like.

The crank 24 has an annular groove 27 opening toward the other end of the diaphragm pump 11 and a projection 28 provided in the annular groove 27.
The driver 25 constitutes a driving mechanism 31 according to the present invention in cooperation with the crank 24, and includes a rod-shaped shaft portion 32 inclined with respect to the axis C of the rotating shaft 23, and a radial direction from the shaft portion 32. And a plurality of arms 33 extending outwardly.
At one end of the shaft portion 32, a first shaft 32a connected to the crank 24 is provided. The first shaft 32 a is movably inserted into the annular groove 27 of the crank 24, and is pushed by the projection 28 as the crank 24 rotates.

At the other end of the shaft portion 32, a second shaft 32b is protruded. The second shaft 32b is rotatably in contact with a concave portion 35 of a diaphragm mounting portion 34 described later. The recess 35 constitutes a self-aligning spherical plain bearing, and is positioned on the same axis as the rotating shaft 23.
The diaphragm mounting portion 34 divides the inside of the housing main body 16 into a motor side space S1 and the other end side, and is integrally formed on the inner peripheral portion of the housing main body 16 by integral molding. The diaphragm 26 is mounted on the diaphragm mounting portion 34 and is sandwiched between the diaphragm mounting portion 34 and the lid 17.

  The plurality of arms 33 of the driver 25 are formed in a shape extending radially about the shaft 32. These arms 33 are provided at positions that divide the shaft 32 into three equal parts in the circumferential direction. Each of the arms 33 penetrates a connecting piece 36 of the diaphragm 26 described later, and is connected to the diaphragm 26 via the connecting piece 36.

  The inclination direction of the driver 25 changes as the crank 24 rotates integrally with the rotating shaft 23 and the first shaft 32 a moves around the axis of the rotating shaft 23. By changing the inclination direction of the driver 25, the position of the arm 33 in the axial direction of the motor 12 changes. Therefore, the drive mechanism 31 including the driver 25 and the above-described crank 24 converts the rotation of the motor 12 into a reciprocating motion and transmits the reciprocating motion to the diaphragm 26.

The diaphragm mounting portion 34 supporting the diaphragm 26 includes a first through hole 42 into which a later-described diaphragm portion 41 of the diaphragm 26 is inserted, and a second through-hole 44 into which a later-described chamber portion 43 of the diaphragm 26 is inserted. , The recess 35 described above.
The first through-holes 42 and the second through-holes 44 are respectively provided at three locations arranged at equal intervals in the circumferential direction of the housing main body 16 according to the configuration of the diaphragm 26.

  As shown in FIG. 1, the diaphragm 26 has a pump body 45 including a plurality of functional units arranged in the radial direction of the housing body 16. The plurality of functional parts include a diaphragm part 41 and a suction valve body 46 located on one side (right side in FIG. 1) in the radial direction of the housing body 16, a chamber part 43 located on the other side in the radial direction, and a discharge part. And a recess 48 for forming a discharge passage. In a state where the plurality of functional units are arranged in the radial direction of the housing main body 16, the pump main body 45 is at a position rotated about the axis of the housing main body 16 by an angle that divides the housing main body 16 into three equal parts in the circumferential direction. Each is provided.

  The diaphragm part 41 is formed in a cup shape that opens toward the other end of the diaphragm pump 11. A pump chamber 51 is formed between the diaphragm part 41 and the lid 17. A piston 52 having the above-described connecting piece 36 is provided at the bottom of the cup-shaped diaphragm portion 41. The connecting piece 36 of the piston 52 provided for each pump body 45 is connected to the three arms 33 of the driver 25 described above.

  The suction valve body 46 is formed in a shape that partially narrows the opening of the cup-shaped diaphragm portion 41. The position of the suction valve body 46 is a position pressed against the end face 17 a on one end side of the lid 17, and is a position at which the first concave portion 53 opened on the end face 17 a is closed. In this embodiment, an intake valve 54 is constituted by the intake valve body 46 and the opening of the first recessed portion 53 with which the intake valve body 46 contacts.

  The first concave portion 53 is connected to the motor-side space S1 in the housing body 16 via a suction passage 55 extending through the inside of the lid 17 and the inside of the diaphragm 26. For this reason, the piston 52 of the diaphragm 26 moves in the direction away from the lid 17 and the volume of the pump chamber 51 increases, so that the intake valve 54 opens, and the air in the first recess 53 is removed from the pump chamber 51. Is sucked. In this embodiment, the first recessed portion 53 and the suction passage 55 correspond to the “intake passage” in the present invention. The suction passage 55 may be formed by a through hole that opens at the bottom of the first recess 53 and the end face 17b on the other end side of the lid 17 as shown by a two-dot chain line in FIG. it can.

The chamber portion 43 is formed in a cup shape that opens toward the lid 17, and is connected to the pump chamber 51 by the second recess 56 of the lid 17 and the communication path 57. The second concave portion 56 is open at an end face 17 a on one end side of the lid 17. Part of the opening of the second recess 56 is closed by the discharge valve 47, and the other part is open to the chamber 43.
The discharge valve body 47 is formed in a shape facing the discharge passage forming concave portion 48 of the diaphragm 26. The position of the discharge valve body 47 is a position pressed against the end face 17a on one end side of the lid body 17 and a position at which a part of the second concave portion 56 opened to the end face 17a is closed. In this embodiment, a discharge valve 58 is constituted by the discharge valve body 47 and a part of the opening of the second recessed portion 56 with which the discharge valve body 47 contacts.

  For this reason, the air sent from the pump chamber 51 flows into the second recess 56 and the chamber 43 through the communication passage 57, and the pressure in the internal space S2 increases. Is opened, and the air is discharged to the discharge passage forming recess 48. The discharge passage forming concave portion 48 is connected to the internal space of the discharge pipe 14 by a third concave portion 59 opened on the end face on the other end side of the lid 17 and a discharge passage 60 in the lid 17. . One end of the internal space is opened at an end face 17 a on one end side of the lid 17, and is closed by the diaphragm 26. The other end of the internal space is open to the other end of the discharge pipe 14. Note that the discharge passage 60 shown in FIG. 1 and the above-described suction passage 55 and the communication passage 57 are drawn in shapes different from actual shapes in order to facilitate understanding of the configuration.

As shown in FIG. 2, the locking structure 21 for fixing the cover 17 to the housing body 16 is provided at a fitting portion between the housing body 16 and the cover 17, and a plurality of locking structures provided on the cover 17 are provided. It is composed of a projection 61 and a projection wall 62 for each projection 61 provided on the housing body 16.
The protrusion 61 is formed in a hemispherical shape that protrudes radially outward (toward the housing body 16) from the outer peripheral surface 17 c of the lid 17. In this embodiment, the outer peripheral surface 17c corresponds to a “fitting surface of the lid that fits with the housing body”. The projection 61 is disposed at one end of the outer peripheral surface 17c of the lid 17 that is close to the diaphragm 26. The protrusions 61 are provided at positions spaced apart from each other at a predetermined interval in the circumferential direction of the lid 17. In this embodiment, the circumferential direction of the lid 17 corresponds to the “direction orthogonal to the fitting direction”.

  Although not shown, a positioning portion is provided on the outer peripheral portion of the lid 17, in addition to the projections formed by the projections 61. The positioning portion positions the lid 17 at a predetermined position in the circumferential direction with respect to the housing body 16. The predetermined position is a position where the first to third concave portions 53, 56, and 59 of the lid 17 correctly face the pump body 45 of the diaphragm 26.

As shown in FIG. 1, the protrusion 61 that forms the locking structure 21 can be arranged at the same position as the pump body 45 of the diaphragm 26 in the circumferential direction of the housing body 16. The protrusion 61 shown in FIG. 1 is arranged near the discharge valve 58.
In the present embodiment, these projections 61 correspond to “projections” in the present invention . In addition to the protrusions 61 formed in this manner, the protrusions may be formed by protrusions extending in the circumferential direction of the lid 17 and having a semicircular cross section or a mountain cross section.

  The protruding wall 62 of the locking structure 21 is provided on the inner peripheral portion of the other end of the housing main body 16 (portion fitted with the lid 17), and is located radially inward of the peripheral wall 16 a of the housing main body 16. (Toward the lid 17). The protruding wall 62 is formed in a shape overlapping the protrusion 61 when viewed from the axial direction of the motor 12. As shown in FIG. 2, a recess 62a into which a part of the projection 61 can be engaged is formed at one end of the projection wall 62 according to this embodiment. The other end of the protruding wall 62 is provided with a rounded portion so that the protruding wall 62 is pushed by the protrusion 61 when the lid 17 is attached to the housing body 16 and is easily displaced outward in the radial direction. 62b are formed. In this embodiment, the protruding wall 62 corresponds to a “wall” in the present invention.

  In order to assemble the housing 15 of the diaphragm pump 11 configured as described above, the lid 17 is pushed into the other end of the housing main body 16 while the diaphragm 26 is mounted on the diaphragm mounting portion 34 of the housing main body 16 and fitted. By doing it. At this time, when the lid 17 is pushed into the opening at the other end of the housing body 16, the projection 61 of the lid 17 pushes the projecting wall 62 of the housing body 16 outward in the radial direction, and the other end of the housing body 16 is pushed. The opening on the side is elastically deformed so as to expand in diameter. When the lid 17 is further pushed in, the projection 61 advances while being in contact with the radially inner end surface 62 c of the protruding wall 62, and engages with the concave portion 62 a of the protruding wall 62.

As the projection 61 engages with the concave portion 62a in this manner, the diaphragm 26 is sandwiched between the lid 17 and the diaphragm mounting portion 34, and the projection 61 is pressed against the protruding wall 62 by the reaction force received by the lid 17 from the diaphragm 26. Can be As a result, the lid 17 is fixed to the housing body 16 without using a fixing member such as a bolt or a spring member which increases the cost.
Further, in the diaphragm pump 11, since the locking structure 21 is provided at the fitting portion between the housing main body 16 and the lid 17, a thin portion is partially formed on the peripheral wall 16a of the housing main body 16. However, the entire area of the peripheral wall 16a can be formed thick so as to increase the sound insulation.
Therefore, according to this embodiment, it is possible to provide a diaphragm pump that can reduce manufacturing costs and reduce noise.

The housing body 16 according to this embodiment is formed in a cylindrical shape. The lid 17 is formed in a disk shape that fits inside the housing body 16. The projections 61 of the locking structure 21 are provided on the outer peripheral surface 17c of the lid 17 at positions spaced apart from each other at a predetermined interval in the circumferential direction of the lid 17. The projecting wall 62 of the locking structure 21 is formed on the inner peripheral portion of the housing body 16.
For this reason, as compared with the case where the protrusion 61 is formed on the inner peripheral portion of the housing main body 16, the structure of the mold for molding the housing main body 16 is simplified, and it is difficult to form a thin portion on the housing main body 16. As a result, a diaphragm pump with lower noise can be provided.

( Reference example of locking structure)
FIG. 3 shows a reference example of the locking structure 21 . 3, the same or equivalent members as those described with reference to FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description will be appropriately omitted.

The locking structure 21 shown in FIG. 3 includes a convex portion 71 protruding from the inner peripheral surface 16b of the housing main body 16 toward the lid 17 and an outer peripheral portion of the lid 17 (a portion fitted to the housing main body 16). And a wall portion 72 provided at the bottom. In this reference example , the inner peripheral surface 16b of the housing main body 16 corresponds to a “fitting surface of the housing main body with which the lid fits”.
The convex portion 71 can be formed by a projection having a semi-spherical cross section or a ridge having a semi-circular cross section. The wall portion 72 is formed in a shape overlapping the convex portion 71 when viewed from the axial direction of the motor 12, and the concave portion 72 a into which the convex portion 71 engages and the convex portion 71 are directed radially outward of the housing body 16. And a rounding portion 72b for pushing. Even in the case of employing the configuration of this reference example, in the circumferential direction of the housing main body 16 and the lid 17 (a direction orthogonal to the fitting direction), the engagement formed by the convex portions 71 and the wall portions 72 at a plurality of positions. A stop structure 21 can be provided.
Even when the configuration shown in FIG. 3 is employed, the same effect as when the configuration shown in FIG. 1 is employed can be obtained.

In the above-described embodiment , an example in which the present invention is applied to the so-called three-cylinder diaphragm pump 11 in which the pump chambers 51 are located at three positions in the circumferential direction of the housing 15 has been described. However, the present invention is not limited to such a limitation and can be applied to a diaphragm pump having one cylinder, two cylinders, or four or more cylinders. In the case of two cylinders or four cylinders, the housing body 16 may be formed in a rectangular tube shape. In such a case, the lid 17 is formed in a plate shape having four sides in plan view.

  DESCRIPTION OF SYMBOLS 11 ... diaphragm pump, 12 ... motor, 15 ... housing, 16 ... housing main body, 16b ... inner peripheral surface, 17 ... lid, 17c ... outer peripheral surface, 21 ... locking structure, 26 ... diaphragm, 31 ... drive mechanism, 34 ... Diaphragm attachment part, 51 ... Pump chamber, 53 ... First concave part, 54 ... Intake valve, 55 ... Suction passage (intake passage), 56 ... Second concave part, 58 ... Discharge valve, 59 ... Third Recesses, 60 ... discharge passages (discharge passages), 61 ... projections (projections), 62 ... projecting walls (walls), 71 ... projections, 72 ... walls.

Claims (2)

A housing main body formed in a cylindrical shape, having a diaphragm mounting portion provided therein and having one end mounted to the motor;
A lid that fits into the opening at the other end of the housing body and closes this opening,
A locking structure provided at a fitting portion between the housing main body and the lid, for restricting movement of the lid fitted to the housing main body in a removing direction;
A diaphragm that is sandwiched and held between the diaphragm mounting portion and the lid and forms a pump chamber between the lid and the lid;
An intake passage provided in the lid, for guiding air to the pump chamber via an intake valve;
A discharge passage provided in the lid, from which air is discharged from the pump chamber via a discharge valve;
A drive mechanism that converts the rotation of the motor into reciprocating motion and transmits the reciprocating motion to the diaphragm, and increases or decreases the volume of the pump chamber,
The locking structure,
A protrusion protruding from the lid body and projecting toward the housing body from a fitting surface of the lid body fitted with the housing body ;
A wall portion that is formed at a portion of the housing main body that fits with the lid, and that overlaps with the protrusion when viewed from the axial direction of the motor ;
The convex portion is the fitting surface of the lid, and is provided at a position separated by a predetermined distance in a direction orthogonal to the fitting direction,
A concave portion in which a part of the convex portion can be engaged is formed at one end of the wall portion on the motor side,
At the other end of the wall opposite to the motor, a rounded portion is formed,
A diaphragm pump in which an end face overlapping with a fitting surface of the lid is formed between the concave portion of the wall and the rounded portion . The diaphragm pump according to claim 1,
The said convex part is formed in the hemispherical shape, The diaphragm pump characterized by the above-mentioned.

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