JP5749590B2 - Diaphragm pump - Google Patents

Description

  The present invention relates to a diaphragm pump for pressurizing or depressurizing fluid to be supplied to a sphygmomanometer, a home appliance, or the like.

  This type of diaphragm pump includes a motor as a drive source, a crank that is rotated by driving the motor, and a portion that is inclined with respect to the rotation axis of the crank at a position that is deviated from the rotation center of the crank. A drive shaft fixed by the drive shaft, a non-through hole into which the other end of the drive shaft is fitted, a drive body rotatably supported by the drive shaft, and a swing end portion of the drive body. Some include a diaphragm to which a diaphragm portion for forming a pump chamber is attached (see, for example, Patent Document 1). In the diaphragm pump described in Patent Document 1, when the crank rotates by driving the motor, the driving shaft rotates around the output shaft of the motor while changing the inclination direction, so that each oscillating end portion of the driving body is rotated. Move back and forth sequentially. Therefore, each pump chamber expands and contracts sequentially, so that the pump chamber expands so that air is sucked from the atmosphere into the pump chamber, and then the pump chamber contracts so that the air in the pump chamber is a pressurized object. Etc.

Japanese Patent No. 2551757

  When assembling the diaphragm pump as described above, one end of the drive shaft is fixed to the crank attached to the output shaft of the motor in advance, and each diaphragm portion of the diaphragm is attached to each swing end of the drive body. Then, the other end of the drive shaft is inserted into a non-through hole provided in the drive body. The operation of fitting the drive shaft in the non-through hole is performed in a state where the opening of the non-through hole is directed downward on the drive shaft inclined with respect to the vertical direction, that is, the opening cannot be visually observed. Since the non-through hole has to be fitted to the drive shaft from above, not only the work is troublesome and skillful, but the workability is not good, and there is a problem that it is an obstacle to the automation of assembly.

  The present invention has been made in view of the above-described conventional problems, and an object thereof is to facilitate the improvement of workability during assembly and the introduction of assembly automation.

  In order to achieve this object, the present invention drives a diaphragm having a diaphragm part that forms a pump chamber, a driver that swings and reciprocates the diaphragm part to expand and contract the pump chamber, and a motor. A diaphragm pump comprising: a crank that rotates as a source; and a drive shaft that is interposed between the crank and the drive body and that converts a rotational operation of the crank into a swinging operation of the drive body. And an engaging groove for engaging the drive shaft with the crank. The engaging groove is formed in a ring shape around the rotation shaft of the crank. The engaging groove is provided with an engaging portion that engages with the drive shaft when the crank rotates and rotates the drive shaft following the rotation of the crank.

  According to the present invention, in the above invention, a guide portion for guiding the drive shaft into the engagement groove is provided in a portion surrounded by the engagement groove of the crank.

  The present invention provides a diaphragm holder for holding the diaphragm according to any one of the inventions, wherein a swing fulcrum shaft is provided on a portion of the drive body opposite to the portion where the drive shaft is provided, The diaphragm holder is provided with a support portion for supporting the swing fulcrum shaft.

  According to the present invention, since the drive shaft is inserted into the engaging groove formed in a ring shape instead of a hole, the insertion work is facilitated and the assembling workability is improved.

  According to one of the inventions, since the drive shaft is guided to the engaging groove by the guide portion, it is not necessary to align the drive shaft with the engaging groove when assembling. Becomes easy.

  According to one of the inventions described above, since the driving body is sandwiched between the crank and the diaphragm holder, the swinging operation of the driving body is stabilized and the expansion / contraction operation of the pump chamber is also stabilized. The pulsating flow of the fluid can be regulated.

It is sectional drawing of the diaphragm pump which concerns on this invention, and shows the state which one pump chamber expanded. It is sectional drawing of the diaphragm pump which concerns on this invention, and shows the state which one pump chamber contracted. The crank in the diaphragm pump which concerns on this invention is shown, The figure (A) is a top view, The figure (B) is a front view, The figure (C) is III (C) -III (C) in the figure (A). Line sectional drawing and the figure (D) are perspective views. The drive body in the diaphragm pump which concerns on this invention is shown, The figure (A) is the perspective view seen from the downward | lower direction, The figure (B) is a front view. The drive body in the diaphragm pump which concerns on this invention is shown, The figure (A) is a top view, The figure (B) is a bottom view. It is sectional drawing which shows 2nd Embodiment of the drive body in the diaphragm pump which concerns on this invention. It is sectional drawing which shows 3rd Embodiment of the drive body in the diaphragm pump which concerns on this invention. It is sectional drawing which shows 4th Embodiment of the drive body in the diaphragm pump which concerns on this invention. It is sectional drawing which shows 5th Embodiment of the drive body in the diaphragm pump which concerns on this invention.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. Note that “upper and lower” used to describe the direction in the specification refers to the direction in the figure for the sake of convenience of explanation, and is the upper and lower when actually using the diaphragm pump according to the present invention. The bottom does not necessarily match.

  A diaphragm pump generally indicated by reference numeral 1 in FIG. 1 includes a motor 2 as a drive source. The motor 2 is attached to the outside of the bottom 3a of the case 3 formed in a bottomed cylindrical shape with bolts so that the output shaft 2a faces the case 3 from a shaft hole provided in the bottom 3a.

  Reference numeral 4 denotes a crank that is formed in a substantially cylindrical shape. As shown in FIG. 3 (C), the crank extends in the vertical direction at the center of the bottom surface, and the output shaft 2a of the motor 2 is press-fitted and axially attached. A hole 4a is provided. On the upper surface of the crank 4, a ring-shaped engaging groove 5 extending in the circumferential direction around the non-through hole 4a (rotating shaft of the crank 4) is formed. The wall surface 5a on the non-through hole 4a side of the engaging groove 5 has an angle α toward the non-through hole 4a (center of the crank 4) upward in the vertical direction as shown in FIG. It is inclined. A part of the engaging groove 5 is engaged with a lower end portion 9c of a driving shaft 9b, which will be described later, engaged with the engaging groove 5 by rotating the crank 4. An engaging portion 5b that rotates following the rotation of 4 is provided.

  Further, a guide portion 6 formed in a conical shape is erected at a portion surrounded by the engaging groove 5 on the upper surface of the crank 4, that is, at the center portion of the upper surface of the crank 4. 6a is inclined from the vertical direction by an angle β larger than the angle α. The lower end of the side surface 6a of the guide portion 6 and the upper end of the inner peripheral surface 5a of the engaging groove 5 described above are connected.

  Reference numeral 7 denotes a driving body, in which three driving elements 7a projecting in a direction orthogonal to the thickness direction are equiangular (120 °) in the circumferential direction in a plan view as shown in FIG. Are provided integrally. As shown in FIG. 4B, these driver elements 7a are formed so as to be slightly inclined downward by the same angle from the base end portion toward the swing end portion side. A diaphragm portion mounting hole 7b is provided.

  Further, as shown in FIG. 4 (B), a swing fulcrum shaft 8 having an upper end formed in a hemispherical shape is projected upward at the center of the upper surface of the driving body 7. Further, in the central portion of the lower surface of the driving body 7, a support portion 9 formed in a columnar shape, a non-sliding contact portion 9a formed in a truncated cone shape provided at the lower end of the support portion 9, and this non-contact portion The drive shaft 9b provided at the lower end of the sliding contact portion 9a is integrally formed with the drive body 7 by resin, and the lower end portion 9c of the drive shaft 9b is formed in a hemispherical shape. The axis 9d of the drive shaft 9b is oriented in a direction substantially orthogonal to the extending direction of the driver 7a, and the drive shaft 9b and the swing fulcrum shaft 8 are oriented in opposite directions with the drive body 7 in between. , Provided on the axis 9d of the drive shaft 9b. Further, the entire length L2 of the drive shaft 9b is formed longer than the depth L1 of the engagement groove 5.

  Reference numeral 10 denotes a diaphragm holder which is formed in an inverted bottomed cylindrical shape and holds a diaphragm 12 which will be described later. At the center of the lower surface of the ceiling portion 11, the above-mentioned swing fulcrum shaft 8 can be freely tilted in the axial direction. In this state, there is provided a bearing portion 11a formed in a concave shape that is rotatably supported around the axis. Further, on the ceiling portion 11, three holding cylinders 11b (only one holding cylinder 11b is illustrated) formed in a cylindrical shape are provided at equal angles (120 °) to each other in the circumferential direction in a plan view. Yes.

  Reference numeral 12 denotes a diaphragm formed in a substantially disk shape by a flexible material such as rubber, and the three diaphragm portions 12a formed in a thin shape are equiangular with each other in the circumferential direction in a plan view (120 °). Is provided. A piston portion 12b is integrally provided at a lower portion of the diaphragm portion 12a, and a small diameter portion 12c is integrally provided at a lower end of the piston portion 12b.

  Reference numeral 13 denotes a valve holder as a partition wall formed in a substantially bottomed cylindrical shape having a cylindrical portion 13a, and an engaging convex portion 13b is projected from the center of the upper surface of the bottom portion. A cylindrical partition wall 13c is erected around. Further, at the bottom of the valve holder 13, there are three discharge holes 13d (only one discharge hole 13d is shown) having an equal angle (120 °) in the circumferential direction in plan view around the engagement convex portion 13b. In addition, three suction holes 13e (only one suction hole 13e is shown) are provided around the partition wall 13c at an equal angle (120 °) in the circumferential direction in plan view.

  In FIG. 1 and FIG. 2, reference numeral 14 denotes a discharge valve element attached to the engaging convex portion 13b and formed in a hat shape for opening and closing the discharge hole 13d. Regulates backflow of fluid. Reference numeral 15 denotes an intake valve element formed in an umbrella shape for opening and closing the suction hole 13e, and restricts the backflow of fluid from the pump chamber 18 to the suction hole 13e.

  In FIGS. 1 and 2, reference numeral 16 denotes a cover body formed in an inverted bottomed cylindrical shape. A cylindrical portion 16a projects integrally downward on the outer peripheral edge, and is concentric with the cylindrical portion 16a at the center. A partition wall 16b formed in a cylindrical shape is integrally protruded downward. A discharge cylinder 16d having a discharge port 16c is integrally provided at the center of the ceiling of the lid 16 and a suction port 16e is formed at a part of the periphery of the ceiling. The suction cylinder 16f is erected integrally.

  Next, a method for assembling the diaphragm pump configured as described above will be described. A valve body 15 for suction is attached to the valve holder 13 in advance, a valve body 14 for discharge is attached to the engaging projection 13b, a lid body 16 is overlaid on the valve holder 13 and sealed by welding or the like. Form. In this state, a ring-shaped suction space 19 is formed between the lid body 16 and the valve holder 13 so as to communicate the suction hole 13e and the suction port 16e, and the discharge hole 13d and the discharge port 16c. A discharge space 20 is formed to allow the two to communicate with each other. Further, the motor 2 is attached to the case 3 with bolts (not shown), and the crank 4 is fixed to the output shaft 2a by press-fitting the non-through hole 4a of the crank 4 into the output shaft 2a of the motor 2.

  Next, each of the diaphragm portions 12 a of the diaphragm 12 is inserted into each holding cylinder 11 b of the diaphragm holder 10, and the diaphragm 12 is placed on the diaphragm holder 10. Next, the narrow diameter portion 12c of each piston portion 12b is attached to the attachment hole 7b of each drive element 7a of the drive body 7, and the swing fulcrum shaft 8 of the drive body 7 is brought into contact with the bearing portion 11a of the diaphragm holder 10. The driving body 7 and the diaphragm 12 are assembled to the diaphragm holder 10 to form a diaphragm holder assembly 22.

  The valve holder assembly 17 is stacked on the diaphragm holder assembly 22 to form a pump assembly 23. In this state, three pump chambers 18 (only one pump chamber 18 is shown) are formed by the valve holder 13 and each diaphragm portion 12a of the diaphragm 12, and three sets of discharge ports of the valve holder 13 are formed in each pump chamber 18. Each of 13d and suction port 13e corresponds. Next, the pump assembly 23 is lowered from above the case 3, and the pump assembly 23 is placed on the case 3, whereby the lower end portion 9 c of the drive shaft 9 b of the drive body 7 is inserted into the engaging groove 5 of the crank 4. Engage with. At this time, a conical guide portion 6 is provided in a portion surrounded by the engagement groove 5 of the crank 4, and the lower end of the side surface 6 a of the guide portion 6 and the upper end of the inner peripheral surface 5 a of the engagement groove 5 are connected. It is installed. Accordingly, the lower end portion 9c of the drive shaft 9b contacts the side surface 6a of the guide portion 6 and descends while being guided by the side surface 6a, and the lower end portion 9c is engaged in the engagement groove 5.

  In this state, as shown in FIG. 2, the lower end of the drive body 7 is supported by the engagement groove 5 via the drive shaft 9b, and the upper end of the drive body 7 is in contact with the bearing portion 11a of the diaphragm holder 10, The drive shaft 9b engaged with the insertion groove 5 falls into the wall surface 5a on the non-through hole 4a side, and the axis 9d of the drive shaft 9b is inclined by an angle α from the vertical direction. Further, the entire length L2 of the drive shaft 9b is formed longer than the depth L1 of the engaging groove 5, and the peripheral surface of the non-sliding contact portion 9a is inclined by the angle β, so that the peripheral surface of the non-sliding contact portion 9a Is separated from the guide portion 6 and is not in contact with the guide portion 6.

  Thus, since the drive shaft 9b is inserted into the engaging groove 5 formed in a ring shape instead of a hole, the insertion work is facilitated and the assembling workability is improved. Accordingly, since the lower end portion 9c of the drive shaft 9b is engaged with the engaging groove 5 of the crank 4 simply by lowering the drive body 7, the non-through hole is formed on the drive shaft inclined with respect to the vertical direction as in the prior art. In the state where the opening portion is directed downward, the troublesome and skillful work of fitting the non-through hole into the drive shaft from above the drive shaft becomes unnecessary. In addition, since the guide portion 6 for guiding the lower end portion 9c of the drive shaft 9b is provided in the engagement groove 5, the lower end portion 9c can be more reliably engaged in the engagement groove 5, so that the assembly is possible. Can be easily introduced.

  The diaphragm pump 1 is formed by integrating the pump assembly 23 and the case 3 with a spring (not shown).

  Next, the pump action in the diaphragm pump 1 configured as described above will be described. When the motor 2 is driven and the crank 4 is rotated via the output shaft 2a, the engaging portion 5b of the engaging groove 5 is engaged with the lower end portion 9c of the driving shaft 9b, so that the driving shaft 9b is engaged with the engaging portion 5b. , While following the rotation of the crank 4 and changing the inclination direction of the axis 9d. Therefore, the respective swing end portions of the three driver elements 7a are sequentially swung in the vertical direction.

  When the swinging end of the first driver 7a moves downward, the first pump chamber 18 expands via the piston portion 12b as shown in FIG. Negative pressure is reached. Therefore, the suction hole 13e is closed by the suction valve body 15 and the suction hole 13e is opened. In this state, air sucked from the outside atmosphere through the suction port 16e of the lid body 16 flows into the first pump chamber 18 through the suction hole 13e through the suction space 19.

  Next, when the swinging end of the driver 7a of the expanded first pump chamber 18 moves upward, the first pump chamber 18 contracts as shown in FIG. Since the pressure of the air in the chamber 18 is increased, the discharge hole 13d is closed by the discharge valve body 14 and the discharge hole 13d is opened, so that the air in the first pump chamber 18 is discharged from the discharge hole 13d. It is supplied to a pressurized object connected to an air tube (not shown) or the like through the discharge port 16c through the space 20.

  Further, the crank 4 rotates via the output shaft 2a, and the swinging end of the second driver 7a moves downward, so that the second pump chamber 18 is expanded. The air becomes negative pressure. Therefore, the suction hole 13e is closed by the suction valve body 15 and the suction hole 13e is opened. In this state, air sucked from the outside atmosphere through the suction port 16e of the lid body 16 flows into the second pump chamber 18 through the suction hole 13e through the suction space 19.

  Next, when the swinging end portion of the driver 7a of the expanded second pump chamber 18 moves upward, the pump chamber 18 contracts, so that the air pressure in the pump chamber 18 increases, and the discharge valve Since the obstruction of the discharge hole 13d by the body 14 is released and the discharge hole 13d is opened, the air in the second pump chamber 18 passes from the discharge hole 13d through the discharge space 16 through the discharge port 16c, and the air tube. (Not shown) or the like to be supplied to an object to be pressed.

  Furthermore, the crank base 5 rotates via the output shaft 2a, and the third pump chamber 18 is expanded by moving the swinging end of the third driver 7a downward. Inside air is in a negative pressure state. Therefore, the suction hole 13e is closed by the suction valve body 15 and the suction hole 13e is opened. In this state, air sucked from the outside atmosphere through the suction port 16e of the lid body 16 flows into the third pump chamber 18 through the suction hole 13e through the suction space 19.

  Next, when the swinging end of the driver 7a of the expanded third pump chamber 18 moves upward, the pump chamber 18 contracts, so the air pressure in the third pump chamber 18 increases. Since the discharge hole 13d is closed by the discharge valve body 14 and the discharge hole 13d is opened, the air in the third pump chamber 18 passes through the discharge port 16c through the discharge space 20 from the discharge hole 13d. Then, it is supplied to a pressurized object connected to an air tube (not shown) or the like. As described above, since the three pump chambers 18 sequentially perform the expansion / contraction operation, air with a small pulsating flow is continuously supplied from the discharge port 16c to the pressurized object.

  Moreover, the swinging movement of the driver 7a is supported by the bearing portion 11a of the diaphragm holder 10 via the swinging fulcrum shaft 8 and swinging about the swinging fulcrum shaft 8 as the swinging center. Therefore, the oscillation width of each driver element 7a is constant, and a stable oscillation operation can be obtained. For this reason, since the expansion / contraction operation of each pump chamber 18 is stable without variation, the amount of air supplied from each pump chamber 18 is constant, so that the pulsating flow due to the supplied air can be regulated.

  Next, a second embodiment of the driving body in the diaphragm pump according to the present invention will be described with reference to FIG. The second embodiment is characterized in that the drive shaft 25 is not integrally formed with the drive body 7 and resin, but the drive shaft 25 is formed of a member different from the drive body 7. . That is, a non-through hole 9e is formed at the center of the lower end of the non-sliding contact portion 9a, and one end portion of the drive shaft 25 formed of metal or a sliding member is press-fitted into the non-through hole 9e and fixed. Has been. Thus, by forming the drive shaft 25 that is relatively heavy with the engaging groove 5 from a metal or a sliding member, the durability and wear resistance of the drive shaft 25 can be improved. Become.

  Next, a third embodiment of the drive body in the diaphragm pump according to the present invention will be described with reference to FIG. In the third embodiment, the drive shaft 9b is integrally formed with the drive body 7 by resin, but the swing fulcrum shaft 26 is characterized by being formed by a member different from the drive body 7. . That is, a non-through hole 7c is formed at the center of the upper surface of the drive body 7, and one end of a swing fulcrum shaft 26 formed of metal or a sliding member is press-fitted into the non-through hole 7c and fixed. Has been. The third embodiment is effective for a negative pressure type diaphragm pump in which a relatively large load is applied to the swing fulcrum shaft 26.

  Next, a fourth embodiment of the driving body in the diaphragm pump according to the present invention will be described with reference to FIG. In the fourth embodiment, the second embodiment and the third embodiment described above are employed at the same time, and the drive shaft 25 and the swing fulcrum shaft 26 are separated from the drive body 7. It is constituted by. In the fourth embodiment, since the functions of the second and third embodiments are combined, the fourth embodiment can be applied to both the pressure type and the negative pressure type, so that the versatility is high.

  Next, a fifth embodiment of the driving body in the diaphragm pump according to the present invention will be described with reference to FIG. In the fifth embodiment, one drive shaft 27 is press-fitted and fixed in a through hole 9f that penetrates the drive body 7 and the support portion 9. A lower portion 27 a of the drive shaft 27 protrudes downward from the support portion 9, is engaged with the engagement groove 5 of the crank 4 described above, and an upper portion 27 b that protrudes upward from the drive body 7 is supported by the bearing portion 11 a of the diaphragm holder 10. Is done. In the fifth embodiment, as compared with the embodiment of the die 4, one drive shaft 27 also serves as a swing fulcrum shaft, so that the number of parts and the number of assembly steps can be reduced.

  In this embodiment, the guide portion 6 is formed in a conical shape. However, the guide portion 6 is not limited to this, and may be formed in a cylindrical shape. In short, the drive shaft 9b is moved when the drive body 7 is lowered. Any shape may be used as long as it abuts and the drive shaft 9 b is guided into the engaging groove 5. In the present embodiment, a so-called three-cylinder diaphragm pump having three pump chambers 18 has been described, but it is needless to say that the present invention can be applied to a diaphragm pump having two cylinders or less, or four cylinders or more.

  DESCRIPTION OF SYMBOLS 1 ... Diaphragm pump, 2 ... Motor, 4 ... Crank, 5 ... Engagement groove, 5b ... Engagement part, 6 ... Guide part, 7 ... Driver, 7a ... Driver, 8, 26 ... Swing fulcrum shaft, 9b , 25, 27 ... drive shaft, 10 ... diaphragm holder, 11a ... bearing part, 12 ... diaphragm, 12a ... diaphragm part, 13 ... valve holder (partition body), 13d ... discharge hole, 13e ... suction hole, 14 ... for discharge Valve body, 15 ... Suction valve body, 16 ... Lid body, 16c ... Discharge port, 16e ... Suction port, 17 ... Diaphragm assembly, 18 ... Pump chamber.

Claims (3)

A diaphragm having a diaphragm portion forming a pump chamber, a drive body that swings to reciprocate the diaphragm portion to expand and contract the pump chamber, a crank that rotates using a motor as a drive source, and the crank and the drive In a diaphragm pump provided with a drive shaft that is interposed between the body and converts the rotational motion of the crank into the swing motion of the drive body,
The drive shaft is integrated by the same member or a different member with the drive body,
An engagement groove for engaging the drive shaft in the crank is provided,
This engaging groove is formed in a ring shape centered on the rotating shaft of the crank,
A diaphragm pump characterized in that an engagement portion is provided in the engaging groove to engage the drive shaft when the crank rotates and to rotate the drive shaft following the rotation of the crank.   The diaphragm pump according to claim 1, wherein a guide portion for guiding the drive shaft into the engaging groove is provided at a portion surrounded by the engaging groove of the crank. A diaphragm holder for holding the diaphragm;
A swing fulcrum shaft is provided at a portion of the drive body opposite to the portion where the drive shaft is provided,
The diaphragm pump according to claim 1 or 2, wherein a bearing portion for receiving the swing fulcrum shaft is provided in the diaphragm holder.

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