JP5453209B2 - Negative pressure type diaphragm pump - Google Patents

Description

  The present invention relates to a negative pressure diaphragm pump that reciprocates a diaphragm portion by driving a motor and evacuates the device by expanding a pump chamber.

  A conventional negative pressure type diaphragm pump is disclosed in Patent Document 1. This will be described with reference to FIG. In the same figure, a negative pressure type diaphragm pump denoted as a whole by reference numeral 101 includes a motor 103 fixed to the outside of the bottom of a case 102 formed in a substantially bottomed rectangular tube shape, and an output shaft 103a of the motor 103 is provided. Is protruded from the hole of the case 102 into the case 102, and a crank base 104 is pivotally attached to the protruding end.

  Reference numeral 105 denotes a metal drive shaft attached at a position where the lower portion is eccentric from the output shaft 103a of the crank base 104 while being inclined with respect to the axial direction of the output shaft 103a. The upper portion is the center of the drive body 106. The drive body 106 is rotatably supported on the drive shaft 105 by being inserted into a non-through hole 107 provided in the portion. The head 106a of the driving body 106 is formed in an arc shape in cross section, and the driving body 106 has a pair of driving elements 108 and 108 at the same angle downward toward the tip so as to be substantially orthogonal to the non-through hole 107. It is formed so as to be slightly inclined, and diaphragm portion mounting holes 108a and 108a are provided at the tip portions of the respective driver elements 108 and 108.

  Reference numeral 110 denotes a diaphragm holder that is open at the bottom and is formed in a box shape. The diaphragm holder 110 has a contact portion 111 with which the head portion 106a of the driving body 106 contacts the center portion of the upper plate, and 2 so as to sandwich the contact portion 111 therebetween. Two holding holes 112, 112 are provided, and are placed on the upper opening end of the case 102. Reference numeral 113 denotes a diaphragm, which is provided with two diaphragm portions 114 and 114 spaced apart from each other by 180 ° in the circumferential direction in a plan view inserted into the holding holes 112 and 112 of the diaphragm holder.

  Pistons 115, 115 are provided below the diaphragm portions 114, 114, and a locking projection 115b is integrally formed at the bottom of each piston portion 115 via a narrow neck portion 115a. ing. The diaphragm 113 is press-fitted into the diaphragm mounting hole 108a of the driver 108 of the driver 106 while elastically deforming the convex portion 115b of the diaphragm section 114, whereby the neck 115a is mounted in the diaphragm mounting hole 108a, and the diaphragm 113 is mounted. It is placed on the holder 110.

  Reference numeral 116 denotes a valve holder, which has two discharge holes 117 and 117 at the center and suction holes 118 and 118 outside the discharge holes 117 and 117. Suction valves 119 and 119 for opening and closing 118 are attached. By holding the diaphragm 113 together with the diaphragm holder 110 by the valve holder 116, pump chambers 120 </ b> A and 120 </ b> B are formed between the valve holder 116 and the diaphragm portions 114 and 114.

  A discharge valve 121 opens and closes the discharge holes 117 and 117. Reference numeral 122 denotes a lid that covers the valve holder 116, a discharge space 123 communicating with the pump chambers 120 </ b> A and 120 </ b> B via the discharge hole 117, and a suction hole 118 around the discharge space 123. And a suction space 124 communicating with the pump chambers 120A and 120B. A discharge cylinder 125 communicates the outside with the discharge space 123, and a suction cylinder 126 communicates the outside with the suction space 124.

  With this configuration, the suction cylinder 126 is connected to a device that evacuates via an air tube or the like, and the discharge cylinder 125 is opened to the atmosphere. If the motor 103 is driven and the output shaft 103a is rotated after such a state, the crank base 104 also rotates integrally, and the drive shaft 105 rotates in an inclined state. The top part 106a in contact with the contact part 111 is swung around the swing center, and both ends of the pair of driver elements 108 reciprocate in the vertical direction in the figure.

  Accordingly, since the two diaphragm portions 114 and 114 are alternately reciprocated in the vertical direction, the two pump chambers 120A and 120B are alternately expanded and contracted. When the pump chambers 120A and 120B are expanded, the air in the apparatus that is evacuated through the suction cylinder 126 through the suction cylinder 126 by the inside of the pump chambers 120A and 120B is in a negative pressure state passes through the suction space 124 and the suction hole 118. Since the air is sucked into 120A and 120B, the inside of the apparatus is decompressed. On the other hand, when the pump chambers 120A and 120B contract, the air in the pump chambers 120A and 120B increases in pressure, and is discharged from the discharge cylinder 125 to the atmosphere through the discharge holes 117 and the discharge space 123.

JP 2009-299530 A

  In the conventional negative pressure type diaphragm pump as described above, the diaphragm 113 is lifted by the force F upward in the figure by the negative pressure generated in the pump chamber 120A when the pump chamber 120A expands, so that the driver 106 is lifted. . Therefore, not only the inner peripheral surface of the non-through hole 107 with which the drive shaft 105 is in contact is worn, but also the abutment portion 111 with which the top portion 106a of the drive body 106 abuts is worn when the drive body 106 is lifted. For this reason, there is a problem that the number of wear countermeasure parts increases because it is necessary to take measures for wear of the two members of the driving body 106 in which the non-through hole 107 is formed and the diaphragm holder 110 in which the contact portion 111 is formed. there were.

  The present invention has been made in view of the above-described conventional problems, and an object thereof is to reduce wear countermeasure parts.

  In order to achieve this object, the present invention provides a crank base that rotates integrally with an output shaft of a motor, and an end portion that is inclined with respect to the output shaft at a portion that is eccentric from the output shaft of the crank base. And a drive shaft having a non-through hole pivotally supported at the other end of the drive shaft and extending in a direction substantially orthogonal to the axis of the non-through hole. A drive body and a diaphragm having a diaphragm portion which is attached to a drive element of the drive body and forms a pump chamber are provided. By swinging the drive body, the diaphragm portion of the diaphragm is reciprocated to expand and contract the pump chamber. In the negative pressure type diaphragm pump that performs the pumping action, the bottom surface of the non-through hole is located farther from the other end of the drive shaft with respect to the pump chamber.

  According to the present invention, when the pump chamber is expanded to evacuate the device, the bottom surface of the non-through hole contacts one end of the drive shaft when the diaphragm is pulled by the negative pressure generated in the pump chamber. For this reason, the place that wears when the pump chamber expands is the bottom surface of the non-through hole and the inner peripheral surface of the non-through hole where the peripheral surface of the drive shaft contacts, and the wear countermeasure component becomes a part of the drive body, Wear countermeasures become easier because the wear countermeasure parts are reduced.

It is sectional drawing of the negative pressure type diaphragm pump which concerns on this invention. It is sectional drawing of the conventional negative pressure type diaphragm pump.

  Hereinafter, an embodiment of the present invention will be described with reference to FIG.

  In the same figure, the negative pressure type diaphragm pump generally indicated by reference numeral 1 has a suction passage 2a formed at one end portion of the bottom portion of the case 2 formed in a substantially bottomed rectangular tube shape. A motor 3 fixed on the outside is provided. An output shaft 3a of the motor 3 protrudes from the hole of the case 2 into the case 2, and a crank base 4 is attached to the protruding end.

  Reference numeral 5 denotes a metal drive shaft that is attached to a portion where the lower portion 5a is eccentric from the output shaft 3a of the crank base 4 while being inclined with respect to the axial direction of the output shaft 3a. The upper end 5b side is substantially cylindrical. The drive body 8 is rotatably supported by the drive shaft 5 via the bearing member 6. The drive body 8 is rotatably supported by the drive shaft 5 via the bearing member 6. That is, the drive shaft 5 is slidably inserted in the non-through hole 7. The drive body 8 includes a pair of driver elements 8A and 8B that are substantially orthogonal to the non-through hole 7 and that are spaced apart from each other by 180 ° in the circumferential direction in plan view. It is formed so as to be slightly inclined upward by the same angle.

  Reference numeral 10 denotes a valve holder which is formed in an inverted bottomed rectangular tube shape and is opened at the lower side, and is placed on the upper opening end of the case 2 so as to communicate with the outside through the suction passage 2a. A discharge space 16 is formed which communicates with the outside through the discharge space 12 and a discharge passage (not shown). Further, the ceiling portion 17 of the valve holder 10 has a suction hole 13 for communicating the suction space 11 and pump chambers 27A and 27B, which will be described later, and a discharge hole 14 for communicating the discharge space 12 and the pump chambers 27A and 27B. Is formed.

  Reference numeral 15 denotes a discharge hole that allows the discharge space 12 and the discharge space 16 to communicate with each other. Reference numeral 18 denotes a suction valve that opens and closes the suction hole 13, and restricts the backflow of air from the pump chambers 27 </ b> A and 27 </ b> B to the suction space 11. A discharge valve 19 opens and closes the discharge hole 14 and restricts the backflow of air from the discharge space 12 to the pump chambers 27A and 27B.

  Reference numeral 20 denotes a diaphragm, which is provided with two diaphragm portions 21A and 21B spaced apart from each other by 180 ° in the circumferential direction in a plan view, and above the diaphragm portions 21A and 21B, the above-described driving body is provided. Pistons 22A and 22B fixed to the eight driver elements 8A and 8B are integrally formed. The diaphragm 20 is sandwiched and fixed by the valve holder 10 and the diaphragm holder 25 to be placed and fixed on the ceiling portion 17 of the valve holder 10, thereby forming pump chambers 27 </ b> A and 27 </ b> B together with the ceiling portion 17. Reference numeral 30 denotes a lid body formed in an inverted bottomed rectangular tube shape, and is loaded on the diaphragm holder 25 so as to cover the driving body 8.

  The negative pressure type diaphragm pump 1 according to the present invention configured as described above is different from the conventional negative pressure type diaphragm pump 101 described above in that the driving body 8 is not located on the motor 3 side, but the pump chambers 27A and 27B are provided. The point which is located on the opposite side to the motor 3 across the point, and the bottom surface 7b of the non-through hole 7 of the drive body 8 is located farther than the upper end 5b of the drive shaft 5 with respect to the pump chambers 27A and 27B. It is in. Therefore, when the driving body 8 is pushed downward by the force F that pulls the diaphragm 20 downward by the negative pressure generated in the pump chambers 27A and 27B when the pump chambers 27A and 27B expand, the bottom surface of the non-through hole 7 7b is comprised so that the upper end 5b of the drive shaft 5 may be contacted.

  With this configuration, the suction cylinder 2a is connected to a device that evacuates via an air tube or the like. In this state, when the motor 3 is driven and the output shaft 3a is rotated, the crank base 4 is also rotated integrally, and the drive shaft 5 is rotated in an inclined state. The pair of driver elements 8A and 8B reciprocate in the vertical direction.

  Therefore, since the two diaphragm portions 21A and 21B reciprocate alternately in the vertical direction, the two pump chambers 27A and 27B are alternately expanded and contracted. When the pump chambers 27A and 27B are expanded, the inside of the pump chambers 27A and 27B is in a negative pressure state, and the air in the apparatus that is evacuated through the suction cylinder 2a passes through the suction space 11 and the suction hole 13, and then the pump chamber. Since the air is sucked into 27A and 27B, the inside of the apparatus is depressurized.

  At this time, when the pump chambers 27A and 27B are expanded, a negative force generated in the pump chambers 27A and 27B generates a force F that pulls the diaphragm 20 downward, and the tensile force F pushes the driver 8 downward. Therefore, the bottom surface 7 b of the non-through hole 7 presses the upper end 5 b of the drive shaft 5. As described above, the bottom surface 7b of the non-through hole 7 is worn by contacting the upper end 5b of the drive shaft 5, and the inner peripheral surface 7a of the non-through hole 7 is also worn, so that when the pump chambers 27A and 27B are expanded. Then, the non-through hole 7 of the bearing member 6 is worn.

  On the other hand, when the pump chambers 27A, 27B contract, the air in the pump chambers 27A, 27B increases in pressure, and thus is discharged to the atmosphere through the discharge holes 14 and the discharge spaces 12 and through the discharge holes 15 and 16. . At this time, since a force for pushing up the driving body 8 is applied, the bottom surface 7b of the non-through hole 7 is separated from the upper end 5b of the driving shaft 5, so that the bottom surface 7b is not worn and only the inner peripheral surface 7a is worn. To do. Eventually, only one part of the bearing member 6 is worn by the expansion / contraction operation of the pump chambers 27A and 27B, and the wear countermeasure parts are reduced to one part compared to the conventional two parts, so that the wear countermeasures are easy. Become.

  In the present embodiment, two cylinders having two pump chambers 27A and 27B have been described. Of course, the present invention can also be applied to one cylinder or more than three cylinders. Further, although the driver elements 8A and 8B are both inclined upward toward the tip, they may be formed so as to be orthogonal to the non-through hole 7 without necessarily being inclined upward.

  DESCRIPTION OF SYMBOLS 1 ... Negative pressure type diaphragm pump, 2a ... Suction passage, 3 ... Motor, 5 ... Drive shaft, 6 ... Bearing member, 7 ... Non-through-hole, 7a ... Inner peripheral surface, 7b ... Bottom surface, 8 ... Driver, 8A, 8B DESCRIPTION OF SYMBOLS ... Driver | operator, 13 ... Suction hole, 14 ... Discharge hole, 15 ... Discharge hole, 16 ... Discharge space, 18 ... Suction valve, 19 ... Discharge valve, 20 ... Diaphragm, 21A, 21B ... Diaphragm part, 25 ... Diaphragm holder, 27A, 27B ... pump chamber, 30 ... lid.

Claims (1)

A crank base that rotates integrally with the output shaft of the motor, a drive shaft having one end portion pivotally attached to a portion that is eccentric from the output shaft of the crank base and inclined with respect to the output shaft, and the drive shaft A drive body having a non-through hole pivotally supported at the other end of the shaft and having a drive element extending in a direction substantially orthogonal to the axis of the non-through hole, and attached to the drive element of the drive body And a diaphragm having a diaphragm portion that forms a pump chamber, and a negative pressure type diaphragm pump that performs a pump action by reciprocating the diaphragm portion of the diaphragm by swinging the driving body to expand and contract the pump chamber ,
The negative pressure type diaphragm pump, wherein a bottom surface of the non-through hole is located farther from the other end of the drive shaft with respect to the pump chamber.

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