JP4144796B2 - Diaphragm pump and method of assembling the same - Google Patents

Description

  The present invention relates to a diaphragm pump that receives an axial load applied to an output shaft of a motor by a reciprocating motion of a diaphragm portion with a thrust bearing provided between a crank base and a pump case.

In this type of diaphragm pump, the crank base rotates integrally with the rotation of the output shaft of the motor, and as the crank base rotates, the drive shaft rotates eccentrically around the output shaft so as to change the inclination direction. . Due to the eccentric rotation of the drive shaft, the diaphragm portion of the diaphragm reciprocates and the pump chamber contracts and expands to perform a pump action, and all the load due to the pump action is applied in the axial direction of the output shaft of the motor. For this reason, this type of diaphragm pump has a problem in the durability of the motor serving as a driving source, compared to a pump portion provided with a diaphragm that performs pumping action by contraction and expansion of the pump chamber. In order to solve this problem, in the conventional diaphragm pump, a thrust bearing that rotatably supports the crank base is interposed between the crank base and the bottom of the pump case, and the motor output is supported by this thrust bearing. An axial load applied to the shaft is received so as not to adversely affect the motor side (see, for example, Patent Document 1). In addition, the applicant could not find prior art documents closely related to the present invention by the time of filing other than the prior art documents specified by the prior art document information described in this specification. .
JP 2002-206629 (paragraph “0011”, FIG. 1)

  In the conventional diaphragm pump described above, as shown in FIG. 4A, a thrust bearing 16 is provided so as to support the crank table 20, and in the motor 2, between the rotor 11 and the bearing 8 and the commutator. A gap is provided between the bearing 12 and the bearing 9 so that the load in the axial direction of the output shaft 10 does not affect the motor 2 side. That is, the output shaft 10 of the motor 2 is provided in advance with a play that can move by a predetermined amount in the axial direction, and a gap δ2 is provided between the upper end of the rotor 11 that is attached to the output shaft 10 and the bearing 8. While providing a gap, the output shaft 10 is press-fitted into the crank table 20 so that a gap δ3 is provided between the lower end of the commutator 12 attached to the output shaft 10 and the bearing 9.

  However, since the output shaft 10 is covered with the motor case 5, the gaps δ2 and δ3 cannot be directly visually confirmed at the time of assembly, and the press-fitting operation of the output shaft 10 relies on intuition. The work had to be done in a register, and the work required skill and extra work time. That is, when the press-fitting amount L1 into the shaft hole 20a of the crank base 20 is smaller than a predetermined amount, the commutator 12 comes into contact with the lower bearing 9 as shown in FIG. When the press-fitting amount L2 into the shaft hole 20a of the table 20 is larger than a predetermined amount, the upper end of the rotor 11 comes into contact with the upper bearing 8 as shown in FIG. Cause. Therefore, the operator must repeatedly adjust the increase / decrease in the press-fitting amount by trial and error depending on intuition as to which of the bearings 8 and 9 is in contact with each other. There was a problem.

  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a diaphragm pump that does not wear or heat due to friction by driving a motor. Another object of the present invention is to improve productivity by facilitating assembling work for preventing an axial load from being applied to the motor side.

In order to achieve this object, the invention according to claim 1 is a motor having an output shaft provided with play in the axial direction and attached to a pump case, a crank base fixed to the output shaft of the motor, A drive body that oscillates in conjunction with the rotation of the crank base, a diaphragm having a diaphragm portion that reciprocates by the oscillation of the drive body, a pump chamber that contracts and expands by reciprocating the diaphragm portion; A thrust bearing provided between the crank base and the pump case for rotatably supporting the crank base, and fluid is sucked into the pump chamber from the suction port and discharged from the discharge port by the contraction / expansion operation of the pump chamber. In the diaphragm pump, a spacer having a thickness smaller than the play in the axial direction of the output shaft is interposed between the pump case and the motor. Those were.
According to a second aspect of the present invention, there is provided a motor having an output shaft provided with play in the axial direction and attached to a pump case, a crank base fixed to the output shaft of the motor, and rotation of the crank base. A drive body that swings in conjunction, a diaphragm having a diaphragm portion that reciprocates by swinging of the drive body, a pump chamber that contracts and expands as the diaphragm portion reciprocates, the crank base, and a pump case And a thrust bearing that rotatably supports the crank table, and a method for assembling a diaphragm pump in which fluid is sucked into the pump chamber from the suction port and discharged from the discharge port by the contraction / expansion operation of the pump chamber The output shaft is press-fitted into the crank base in a state where the play in the axial direction of the output shaft is secured, and then the pump casing is Between the scan and the motor, interposed a spacer thickness smaller than the clearance in the axial direction of the output shaft, in assembling method of fixing the motor to the pump casing in this state.

  According to the present invention, wear and heating are prevented by friction caused by driving of the motor. In addition, productivity can be improved because assembly can be performed easily and in a short time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 is a cross-sectional view of a diaphragm pump according to the present invention, FIG. 2 is a cross-sectional view of an essential part for explaining the assembly method, and FIG. 1 (a) shows a state in which a crank base is press-fitted into an output shaft of a motor. FIG. 3B shows a state in which a spacer is interposed, FIG. 3 shows the spacer, FIG. 3A is a plan view, and FIG. 3B is III (b) − in FIG. It is III (b) sectional view taken on the line.

  The diaphragm pump generally indicated by reference numeral 1 in FIG. 1 includes a motor 2 that is a driving source and a pump unit 3 that is driven by the motor 2 to perform a pumping action. Reference numeral 5 denotes a motor case, which is formed in a cap shape having an opening at the bottom. An opening 5a with a bearing 8 attached to the center of the ceiling is provided, and a screw hole 5b is screwed around the periphery of the ceiling. Has been. Reference numeral 6 denotes a bottom plate that closes the lower opening of the motor case 5. A concave portion 6 a for attaching a bearing 9 is provided at the central portion, and a shaft hole 6 b is provided at the central portion of the concave portion 6 a. A motor housing 7 is formed by the motor case 5.

  An output shaft 10 is supported by the bearings 8 and 9 so as to be rotatable and movable in the axial direction. A rotor 11 is provided at the center and a commutator 12 is provided at the bottom. A permanent magnet 13 is fixed to the inner peripheral surface of the motor case 5 so as to face the rotor 11. In the motor 2 having such a structure, the output shaft 10 is provided with play in the axial direction with respect to the motor case 5. That is, as shown in FIG. 2 (a), the output shaft 10 moves slightly in the direction of arrow A due to its own weight, and the commutator 12 is in contact with the lower bearing 9, and the upper end of the rotor 11 and the upper bearing A gap 19 having a distance δ is formed between the output shaft 10 and the output shaft 10, and the output shaft 10 can move upward by this distance δ. This is the play δ in the axial direction of the output shaft 10.

  Reference numeral 15 denotes a pump case formed in a bottomed cylindrical shape with an opening at the top. A hole 15a is provided at the center of the bottom, and a recess 15b is provided at the upper edge of the hole 15a. An insertion hole 15c is provided around 15a, and a groove 15d extending in the up-down direction in which a regulating piece 18a of a spacer 18 described later is fitted is formed in a part of the outer peripheral portion. Reference numeral 16 denotes a thrust bearing attached to the recess 15b. The thrust bearing 16 is provided between the bottom of the pump case 15 and a crank base 20 described later, and rotatably supports the crank base 20.

  Next, when the motor 2 having such a configuration is attached to the pump case 15 with reference to FIGS. 1 to 3, a predetermined amount of clearance is provided between the rotor 11 and commutator 12 of the motor 2 and the bearings 8 and 9. An assembling method for providing the above will be described.

  A reference numeral 18 in FIG. 3 is a spacer that is a feature of the present invention, and is formed in a substantially disk shape by a plate material having a thickness γ, and is bent at a right angle on a part of the circumference. The restriction piece 18a is formed by bending, and a U-shaped groove 18b is provided at the center. A thickness γ of the spacer 18 is smaller than the play δ in the axial direction of the output shaft 10.

  As shown in FIG. 2A, the pump case 15 is placed on the motor case 5 and the bottom plate 6 and the crank table 20 are pressed from above and below so as to sandwich the bottom plate 6 and the crank table 20 of the motor 2. The output shaft 10 is press-fitted into the shaft hole 20 a of the crank table 20 until the crank table 20 contacts the upper end of the thrust bearing 16. In this state, since the output shaft 10 does not move upward while the lower end of the commutator 12 remains in contact with the lower bearing 9, the gap δ is between the upper end of the rotor 11 and the upper bearing 8. The gap 19 is still provided. That is, the output shaft 10 is press-fitted into the shaft hole 20a of the crank table 20 while the play δ in the axial direction of the output shaft 10 is secured.

  Next, the pump case 15 is moved slightly in the direction of the arrow B as shown in FIG. 4B, a gap is formed between the pump case 15 and the motor case 5, and a spacer 18 is inserted into this gap. The restriction piece 18 a of the spacer 18 is fitted into the groove 15 d of the pump case 15. When the pump case 15 is placed on the spacer 18, the thickness γ of the spacer 18 is formed to be smaller than the play δ in the axial direction of the output shaft 10. Therefore, as shown in FIG. Is formed with a gap 21 having an interval (δ−γ) = δ1. Further, a gap 22 having the same interval as the thickness γ of the spacer 18 is formed between the commutator 12 and the bearing 9.

  In this state, that is, with the spacer 18 interposed between the motor case 5 and the pump case 15, the screw 23 is inserted into the insertion hole 15 c formed in the bottom of the pump case 15 and the groove 18 b of the spacer 18. The motor 2 is attached to the pump case 15 by being screwed into the screw hole 5a of the motor case 5. At this time, since the regulating piece 18a of the spacer 18 is fitted in the groove 15d of the pump case 15, the spacer 18 will not be displaced. In this state, a gap 21 having a gap δ1 is formed between the upper end of the rotor 11 and the bearing 8, and a gap 22 having the same gap as the thickness γ of the spacer 65 is formed between the commutator 12 and the bearing 9. Is formed.

  In this way, the operation for press-fitting the output shaft 10 into the shaft hole 20a of the crank table 20 is determined by the predetermined amount of press-fitting by the crank table 20 coming into contact with the thrust bearing 16, so the press-fitting amount of the output shaft 10 is adjusted. There is no need to do. Further, by interposing the spacer 18 between the pump case 15 and the motor case 5, a gap 21 is automatically provided between the rotor 11 and the bearing 8 of the motor 2 and between the commutator 12 and the bearing 9. , 22 can be formed. Therefore, since it is not necessary to form the gaps 21 and 22 by using the operator's intuition as in the prior art, the assembly can be performed easily and in a short time, so that productivity is improved.

  In this way, the drive shaft 24 is fixed to the crank base 20 fixed to the output shaft 10 at a position eccentric from the axis of the output shaft 10 while being inclined with respect to the output shaft 10. Reference numeral 25 denotes a drive body. A shaft hole 25a into which a drive shaft 24 is rotatably inserted is recessed at the center, and the upper end extends radially from the center at an equal angle in the circumferential direction in plan view. The three driving elements 26 are integrally formed. These three driver elements 26 are all inclined downward by the same angle from the center toward the tip, and mounting holes for attaching diaphragm portions 33 of a diaphragm 32 to be described later are provided on the tip side of each driver element 26. 26a is provided.

  The diaphragm holder denoted by reference numeral 28 in the same figure is formed in a substantially cap shape, and three diaphragm portion holding holes 30 are provided at an equal angle in the circumferential direction in the ceiling portion 29. This diaphragm holder 28 is These are placed on the pump case 15 described above.

  The diaphragm denoted by reference numeral 32 in the figure is made of a flexible material such as rubber, and is provided with three diaphragm portions 33 which are provided at equal angles in the circumferential direction in a plan view and open upward, and these three diaphragm portions 33. It is integrally formed by the flange 34 formed in the substantially disc shape which connects the upper end part of this. A piston 35 having a substantially frustoconical cross section is integrally formed on the lower surface of each diaphragm portion 33, and a locking projection 36 is integrally formed on the lower portion of the piston 35, A second valve body 37 that is formed in a cylindrical shape is erected integrally at the center.

  The diaphragm 32 is attached to the diaphragm portion attachment hole 26a by being inserted into the diaphragm portion attachment hole 26a of each driver 26 of the drive body 25 while elastically deforming the convex portion 36 of each diaphragm portion 33. In addition, each diaphragm portion 33 is inserted into the diaphragm portion holding hole 30 of the diaphragm holder 28 and placed on the ceiling portion 29 of the diaphragm holder 28.

  The valve holder denoted by reference numeral 40 in the figure is formed in a substantially disc shape, and a large-diameter cylinder 41 is integrally provided at the center of the valve holder 40 and surrounded by the cylinder 41. A cylindrical valve chamber 42 is formed at the site. A second valve body 37 facing the valve chamber 42 is in close contact with the inner peripheral surface of the cylindrical body 41, and the inner peripheral surface of the cylindrical body 41 is formed in a groove shape communicating with each pump chamber 52 described later. The three exhaust passages 43 are recessed at equal angles in the circumferential direction.

  The second valve body 37 is in close contact with the inner peripheral surface of the cylindrical body 41 so as to close the space between the valve chamber 42 and the exhaust passage 43. Therefore, the second valve body 37 and the inner peripheral surface of the cylinder 41 constitute a check valve that restricts the flow of fluid from the discharge port 46 described later through the exhaust passage 43 to the pump chamber 52.

  On the upper side of the large-diameter cylinder 41, a small-diameter cylinder 45 having a hollow portion communicating with the valve chamber 44 is integrally provided. An upper end opening of the cylinder 45 forms a discharge port 46. Yes. Further, around the large-diameter cylindrical body 41, three first valve body mounting holes 47 are drilled at equal angles in the circumferential direction, and around these first valve body mounting holes 47, A number of intake passages 48 are perforated.

  The first valve body denoted by reference numeral 50 in the same figure is formed in an umbrella shape from a flexible material such as rubber, and is attached to the first valve body mounting hole 47, whereby the intake passage 48 and the pump It closely adheres to the lower surface of the valve holder 40 so as to close the space between the chambers 52. Therefore, the first valve body 50 and the lower surface of the valve holder 40 constitute a check valve that restricts the flow of fluid from the pump chamber 52 to the intake passage 48.

  The valve holder 40 is placed on the diaphragm holder 28 so as to sandwich the diaphragm 32 together with the diaphragm holder 28, and forms three pump chambers 52 together with the diaphragm portions 33 of the diaphragm 32. The three exhaust passages 43 and the three sets of intake passages 48 of the valve holder 40 are positioned so as to correspond to the respective pump chambers 52. The pump case 15, the diaphragm holder 28, and the valve holder 40 are integrated by a rod-shaped (linear) spring, a leaf spring, or a through screw (not shown).

  The lid body denoted by reference numeral 55 in the same figure is formed in a substantially cap shape by a ceiling portion 56 and a cylinder portion 57, and a fitting hole into which the above-described cylinder body 45 is fitted in the central portion of the ceiling portion 56. 58 is provided, and a cylindrical body 59 is erected integrally at a part of the periphery, and an opening of the cylindrical body 59 forms the suction port 60. By fitting the fitting hole 58 of the lid body 55 configured in this way into the cylinder body 45 of the valve holder 40 and joining the lower end of the cylinder portion 57 and the upper end of the valve holder 40 by welding, this lid A space sealed by the body 55 and the valve holder 40 is partitioned by the cylinder 41, and an intake space 61 is formed between the intake port 60 and the intake passage 48.

  In the diaphragm pump 1 configured as described above, when the motor 2 is driven and the output shaft 10 rotates, the crank base 20 also rotates integrally, and the crank base 20 is inclined to a position eccentric from the axis of the output shaft 10. The drive shaft 24 fixed in this state rotates eccentrically around the output shaft 10 so as to change the inclination direction. Therefore, each drive element 26 of the drive body 25 rotatably supported by the drive shaft 24 is swung up and down sequentially, and each diaphragm portion 33 of the diaphragm 32 is also moved up and down sequentially, so that each pump chamber 52 is sequentially expanded and contracted. Performs pumping action. Due to this pumping action, an axial load is applied to the output shaft 10, and this load is received by the thrust bearing 16 and between the rotor 11 and the bearing 8 of the motor 2 and between the commutator 12 and the bearing 9. Since the gaps 21 and 22 are provided, no load in the axial direction is applied to the motor 2 side, so that the durability of the motor 2 can be improved.

  In the present embodiment, the drive body 25 is swung via the drive shaft 24 attached to the crank base 20 at an angle, but instead of the drive shaft 24, the crank base 20 It is also possible to provide a swinging portion with an inclined rotation axis at the upper end portion, and to swing the drive body 25 by coupling the swinging portion to the drive body 25 so as to be rotatable. Further, although the drive body 25 is rotatably supported on the drive shaft 24, the drive body 25 and the drive shaft 24 may be integrated so that the drive shaft 24 is rotatably supported on the crank table 20. Further, the spacer 18 is formed in a substantially disc shape, but is not limited to this shape, and various design changes are possible. In short, the thickness of the spacer is determined by the play δ in the axial direction of the output shaft 10. May be formed small.

It is sectional drawing of the diaphragm pump which concerns on this invention. FIG. 2 is a cross-sectional view of a main part for explaining a method of assembling a diaphragm pump according to the present invention, in which FIG. (A) shows a state in which a crank base is press-fitted into an output shaft of a motor, and FIG. The state to wear is shown. The spacer in the diaphragm pump which concerns on this invention is shown, The figure (a) is a top view, The figure (b) is the III (b) -III (b) sectional view taken on the line in the figure (a). FIG. 4A is a cross-sectional view of a main part of a conventional diaphragm pump, in which FIG. 1A shows a normally assembled state, and FIGS. 2B and 2C show a state where the diaphragm pump is not normally assembled.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Diaphragm pump, 2 ... Motor, 3 ... Pump part, 5 ... Motor case, 8, 9 ... Bearing, 10 ... Output shaft, 11 ... Rotor, 12 ... Commutator, 15 ... Pump case, 16 ... Thrust bearing, 18 ... Spacer, 19 ... Gap, 20 ... Crank base, 20a ... Shaft hole, 21, 22 ... Gap, 23 ... Screw, 24 ... Drive shaft, 25 ... Drive body, 32 ... Diaphragm, 33 ... Diaphragm part, 37 ... Second , 43 ... discharge passage, 48 ... suction passage, 50 ... first valve body, 52 ... pump chamber.

Claims (2)

  A motor having an output shaft provided with play in the axial direction and attached to the pump case; a crank base fixed to the output shaft of the motor; and a drive body that swings in conjunction with the rotation of the crank base; A diaphragm having a diaphragm portion that reciprocates when the drive body swings, a pump chamber that contracts and expands when the diaphragm portion reciprocates, and a crank table that rotates between the crank table and the pump case. A diaphragm bearing that freely supports, in a diaphragm pump in which fluid is sucked into the pump chamber from the suction port and discharged from the discharge port by the contraction / expansion operation of the pump chamber, between the pump case and the motor, A diaphragm pump comprising a spacer having a thickness smaller than the play in the axial direction of the output shaft. A motor having an output shaft provided with play in the axial direction and attached to the pump case; a crank base fixed to the output shaft of the motor; and a drive body that swings in conjunction with the rotation of the crank base; A diaphragm having a diaphragm portion that reciprocates when the drive body swings, a pump chamber that contracts and expands when the diaphragm portion reciprocates, and a crank table that rotates between the crank table and the pump case. A diaphragm bearing that is freely supported, and a diaphragm pump assembly method in which fluid is sucked into the pump chamber from the suction port and discharged from the discharge port by the contraction / expansion operation of the pump chamber, in the axial direction of the output shaft With the play secured, the output shaft is press-fitted into the crank base, and then the output case is interposed between the pump case and the motor. Interposed a spacer thickness smaller than the clearance in the axial direction of the shaft, the assembly method of the diaphragm pump, characterized in that to fix the motor to the pump casing in this state.

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