JP2015010499A - Gear pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent failure caused by intrusion of coating or separated pigment between an outer periphery of a shaft and a supporting hole.SOLUTION: Seal members 39 and 40 are respectively provided in an upper supporting hole 33 for supporting a driven shaft 35 and a lower supporting hole 34 for supporting a driving shaft 37. A first cleaning liquid flow passage 42 for supplying thinner to an outer side part of the seal members 39 and 40 in the supporting holes 33 and 34 is provided in a body 26. In-shaft cleaning liquid flow passages 43 and 44, each having an inlet part opened in an end surface center part and opened in the inner side of the seal members 39 and 40 are provided in ends of the shafts 35 and 37. A second cleaning liquid flow passage 45 for supplying the thinner to the in-shaft cleaning liquid flow passages 43 and 44 is provided in a closing plate 28. The first cleaning liquid flow passage 42 is communicated with the second cleaning liquid flow passage 45 through a communication passage 46.

Description

  The present invention relates to a gear pump in which liquid is sucked into a pump chamber from a suction passage and discharged from a discharge passage by rotation of a gear.

  For example, a gear pump that is relatively inexpensive and easy to control is known as a pump for transferring (pressure-feeding) a coating material toward a spray gun in a coating apparatus (see, for example, Patent Document 1). FIG. 7 schematically shows the configuration of a conventional gear pump 1. The gear pump 1 includes a casing 3 having a gear chamber 2, a drive shaft 4 and a driven shaft 5 rotatably supported by the casing 3, and a lower portion and an upper portion in the gear chamber 2 which are respectively attached to the drive shaft 4 and the driven shaft 5. And a drive gear 6 and a driven gear 7 disposed in the casing 3, a suction portion 8 provided in the casing 3 and connected to the gear chamber 2, and a discharge portion (not shown).

  The rear end portion (right side in the figure) of the drive shaft 4 is connected to a drive motor (not shown) and rotated, whereby the drive gear 6 and the driven gear 7 are rotated. Thus, as indicated by an arrow a, the paint flows into the gear chamber 2 from the suction portion 8 and is discharged from the discharge portion by a predetermined amount. Although not shown, a seal member (packing) is provided between the outer peripheral surface of the drive shaft 4 and the driven shaft 5 and the inner peripheral surface of the casing 3 (support hole) to prevent paint leakage or the like. Is provided.

  In addition to the above-described paint passage, the gear pump 1 has a first thinner passage 9 provided in the drive shaft 4 for supplying thinner and air during cleaning (when changing the paint color). A second thinner passage 10 provided in the driven shaft 5 is provided. These thinner passages 9 and 10 are configured to have an inlet opening at the front surface (left side in the drawing) of the casing 3 and an outlet opening at the outer peripheral surface of each shaft 4 and 5. By supplying thinner to the thinner passages 9 and 10, as indicated by the arrow b, the inside of the gear chamber 2, the gears 6 and 7, the outer periphery of the shafts 4 and 5, and the like are cleaned. ing.

Japanese Patent Laid-Open No. 7-80366 (FIG. 10 etc.)

  By the way, some of the paints contain fine pigments (solid matter), and because the viscosity of the main agent is low, the pigment is easily separated from the main agent. In addition, there are types that are highly reactive and easily cured, such as UV curable paints and two-component paints. In the conventional gear pump 1, when the paint is transferred as described above, the paint enters between the outer periphery of the shafts 4 and 5 and the support hole of the casing 3, and the pigment adheres to the seal portion and wear occurs. As a result, the durability of the sealing member may be reduced, or the curing reaction of the paint may be accelerated by friction and may be fixed to the shafts 4 and 5.

  Therefore, conventionally, in a coating system using a paint in which pigments are easily separated or a curing reaction is likely to occur, a syringe pump or the like is generally used without using a gear pump. However, the syringe pump is more complicated in configuration and control than the gear pump and is expensive, and it is desired to use an inexpensive gear pump when constructing a coating system.

  The present invention has been made in view of the above circumstances. The purpose of the present invention is to transfer paint or paint between the outer periphery of the shaft and the support hole, even when the paint is easily separated or the curing reaction is likely to occur. It is an object of the present invention to provide a gear pump that can prevent a problem that occurs when a separated pigment enters.

  A gear pump according to the present invention includes a body, a pump chamber formed by connecting a closing plate to the tip of the body, a suction passage and a discharge passage communicating with the pump chamber, and the pump chamber provided in the body. Two support holes that open at the rear wall and extend rearward, two shafts that are rotatably supported by the respective support holes and whose tips are located in the pump chamber, and the outer circumferences of the tips of these shafts And two gears that are fitted and disposed in the pump chamber, and the rotation of the gear causes the liquid to be sucked into the pump chamber and discharged from the discharge passage. A seal member that provides a fluid-tight seal between the support hole and the outer peripheral surface of the shaft is provided on the inner peripheral portion of the opening end portion on the pump chamber side of each support hole. Within And a first cleaning liquid flow path for supplying a cleaning liquid to an outer portion of the sealing member provided in the support hole and provided in the support hole; and An in-shaft cleaning liquid flow path that is provided on the shaft and has an inlet portion that opens at the center of the front end surface of the shaft and extends rearwardly from the inlet portion to the inside of the seal member in each of the support holes. And a second cleaning liquid channel having a cleaning liquid supply port for supplying a cleaning liquid to the cleaning liquid channel in the shaft at a position provided on the closing plate and wrapping at the inlet of each shaft. (Invention of claim 1)

  According to the above configuration, for example, when the liquid is transferred by the rotation of the gear, the cleaning liquid can be supplied to the outer portion of the seal member in each support hole through the first cleaning liquid channel. At this time, if the pressure of the cleaning liquid supplied to the outer part of the seal member is set to a pressure equal to or higher than the pressure of the liquid in the pump chamber, that is, the pressure inside the seal member, the liquid in the pump chamber Further, it is possible to prevent the solid matter in the portion from entering the space between the outer periphery of the shaft and the inner periphery of the support hole beyond the seal portion by the seal member.

  In addition, in the case where there is no problem even if the cleaning liquid is mixed into the pump chamber somewhat and mixed with the liquid, a small amount of cleaning liquid is supplied from the second cleaning liquid flow path, so that It can be supplied to the inner part of the seal member in the support hole. By supplying the cleaning liquid, it is possible to discharge the liquid that is about to enter the support hole and the solid matter therein to the pump chamber side. Here, as the “cleaning liquid” in the present invention, for example, when the liquid to be transferred is a paint, a solvent such as thinner is included, and even if such a solvent is supplied into the pump chamber, the liquid ( The paint) needs only be slightly diluted and can be done without adverse effects.

  Further, when cleaning the pump chamber and the gear part, if the cleaning liquid is supplied through the second cleaning liquid flow path, the cleaning liquid flows from the cleaning liquid supply port to the cleaning liquid flow path in the shaft from the inlet portion of the front end surface of each shaft, and the cleaning liquid in the shaft Through the opening of the flow path, the cleaning liquid can flow to the inner part of the seal member in each support hole. As a result, the liquid remaining in the inner part of the seal member in the support hole and the solid matter therein can be discharged from the support hole and cleaned. Furthermore, by supplying the cleaning liquid at a high pressure to the first cleaning liquid flow path, the cleaning liquid can be forcibly passed from the outside toward the inside to clean the seal part.

  In the present invention, the terminal end of the first cleaning liquid flow path and the start end of the second cleaning liquid flow path are connected by a communication path located outside the pump chamber, and the first cleaning liquid flow path is connected to the first cleaning liquid flow path. The cleaning liquid that has passed through the cleaning liquid flow path can flow into the second cleaning liquid flow path through the communication path and be supplied to the in-shaft cleaning liquid flow path (Invention of Claim 2). . According to this, since the flow path for supplying the cleaning liquid to both the first cleaning liquid flow path and the second cleaning liquid flow path is a single system, the configuration can be simplified.

  According to the gear pump of the present invention, the inner peripheral portion of the opening end portion of each support hole on the pump chamber side is provided with a seal member that seals the space between the outer peripheral surface of the shaft and the pump by the seal member. A first cleaning liquid flow path for supplying a cleaning liquid to an outer portion of a seal member provided in the support hole and configured to be partitioned between an inner side which is a chamber side and an outer side opposite to the chamber side; An in-shaft cleaning liquid flow path that is provided in each shaft and has an inlet portion that opens at the center of the front end surface of the shaft, extends rearwardly from the inlet portion and opens inside the seal member in each support hole; Since the second cleaning liquid channel having the cleaning liquid supply port for supplying the cleaning liquid to the cleaning liquid channel in the shaft is provided at the position provided on the closing plate and wrapping at the inlet of each shaft, the pigment is Easy to separate In other words, even when a paint that is likely to undergo a curing reaction is transferred, it is possible to prevent problems that may occur when the paint or separated pigment enters between the outer periphery of the shaft and the support hole. Excellent effect.

1 shows an embodiment of the present invention and is a vertical right side view of a gear pump body. Longitudinal front view of the gear pump body along the line AA in FIG. Transverse plan view of the gear pump main body along the line BB in FIG. Perspective view of gear pump body from diagonally rear The figure which shows typically the distribution route of the paint and thinner in the gear pump Diagram showing the overall configuration of the painting equipment Shows a conventional example, schematic vertical right side view of gear pump

  Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. In this embodiment, the present invention is applied to a gear pump for quantitative transfer of paint in a coating apparatus. First, the overall configuration of the coating apparatus 11 (coating system) in the present embodiment will be briefly described with reference to FIG.

  That is, the coating apparatus 11 supplies a paint supply source 12 such as a tank that stores the paint as a liquid, a diaphragm pump 14 that pumps the paint from the paint supply source 12 and supplies the paint to the paint supply path 13, and supplies it to the paint supply path 13. And a regulator 15 for adjusting the pressure of the paint to be applied. Then, the paint passing through the paint supply path 13 is transferred (pressure-fed) by a gear pump 16 according to the present embodiment to a coating machine (spray gun) 17 that sprays the paint on the work in a fixed amount (or constant pressure). The As will be described in detail later, the gear pump 16 is configured by connecting a drive motor 19 to a gear pump body 18.

  On the other hand, the coating apparatus 11 includes a thinner supply source 20 that stores thinner as a cleaning liquid, a diaphragm pump 22 that pumps the thinner from the thinner supply source 20 and supplies the thinner to the thinner supply path 21, and a thinner supplied to the thinner supply path 21. Regulators 23 and 24 for adjusting the pressure in two stages of high pressure and low pressure, and a switching valve 25 for switching the pressure of the thinner supplied to the thinner supply path 21. The thinner supply path 21 is connected to the gear pump 16 (gear pump body 18), so that thinner is supplied to the gear pump 16 at a high pressure or a low pressure.

  Here, the gear pump 16 (gear pump body 18) will be described with reference to FIGS. 1 to 4 show the configuration of the gear pump main body 18. In the following description, for the sake of convenience, the side where the pump chamber of the gear pump body 18 is formed will be described as the front, and the side where the drive shaft connected to the drive motor 19 protrudes will be described as the rear. The gear pump main body 18 is configured by connecting a closing plate 28 to a front side of a body 26 having a substantially rectangular block shape with a housing 27 interposed therebetween. A flange 29 is provided on the rear surface of the body 26.

  As shown in FIG. 2 and the like, the housing 27 has a rectangular plate shape whose outer shape corresponds to the front surface of the body 26, and has an approximately 8 character shape (dharma type) in which two upper and lower circles are connected to the inside. It has a hole. The closing plate 28 has a rectangular plate shape corresponding to the front surface of the body 26 and is disposed on the front surface side of the housing 27. Thus, a pump chamber 30 surrounded by the front surface of the body 26, the inner wall surface of the hole of the housing 27, and the back surface of the closing plate 28 is formed at the distal end portion of the body 26.

  As shown in FIG. 3, the body 26 is formed with a suction passage 31 and a discharge passage 32 that are connected to the pump chamber 30. Among them, the suction passage 31 has an inlet port 31a on the left side wall of the body 26, extends rightward in the body 26, and then bends at a right angle to the front, as shown in FIG. The pump chamber 30 is opened at the left end of the middle part in the vertical direction (the part where the two circles overlap). Further, as shown in FIG. 2, the discharge passage 32 opens at the front end of the body 26 at the right end of the intermediate portion in the vertical direction of the pump chamber 30, and extends rearward in the body 26. The right side wall of the body 26 is connected to the outlet port 32a. The inlet port 31a is connected to the distal end portion of the paint supply path 13, and the outlet port 32a is connected to the base end portion of a hose (not shown) that sends the paint to the coating machine 17.

  Further, as shown in FIG. 1, the body 26 is located at the upper part and the lower part (each central part of the two circles of the pump chamber 30), and supports the upper and lower parts extending (penetrating) in the front-rear direction. Holes 33 and 34 are formed. Of these, the driven shaft 35 is inserted into the upper support hole 33 and is rotatably supported. As shown in FIG. 2, the driven shaft 35 is configured to have a slightly large diameter at its tip, and the large diameter portion is disposed in the pump chamber 30, and the driven gear 36 is fitted and fixed on the outer periphery thereof. Has been.

  A drive shaft 37 is inserted into the lower support hole 34 and is rotatably supported. The drive shaft 37 has a slightly large diameter at the tip, and as shown in FIG. 2, the large diameter portion is disposed in the pump chamber 30 and the drive gear 38 is fitted and fixed to the outer periphery thereof. Has been. The drive gear 38 meshes with the driven gear 36. As shown in FIG. 1, the rear end portion of the drive shaft 37 penetrates the flange 29 and protrudes to the outside. The upper support hole 33 is closed by a flange 29, and the driven shaft 35 is in sliding contact with the front surface of the flange 29.

  Although not shown in detail, the rear end portion of the drive shaft 37 is connected to the drive motor 19 so that the drive shaft 37 is rotated. Due to the rotation of the drive shaft 37, the drive gear 38 is driven to rotate, and the driven gear 36 (and the driven shaft 35) is also driven to rotate in the opposite direction. At this time, the end surfaces (left side in FIG. 1) of the driving gear 38 and the driven gear 36 slide on the front surface of the closing plate 28, and end surfaces on the rear end side of the driving gear 38 and the driven gear 36 (in FIG. 1). (Right side) slides in front of the body 26. As the gears 38 and 36 rotate, the paint is sucked into the pump chamber 30 from the suction passage 31 and discharged from the discharge passage 32. The amount of paint transferred at this time is a value (quantitative) corresponding to the rotational speed of the drive gear 38.

  In the present embodiment, as shown in FIG. 1, the tip end portions (open end portions on the pump chamber 30 side) of the upper support hole 33 and the lower support hole 34 are larger in diameter than the other portions. It is set as the parts 33a and 34a. A seal member 39 such as packing is provided on the inner peripheral portion of the large-diameter portion 33 a of the upper support hole 33 to seal the space between the driven shaft 35 and the outer peripheral surface. Similarly, a sealing member 40 such as packing is provided on the inner peripheral portion of the large-diameter portion 34 a of the lower support hole 34 to seal the space between the outer peripheral surface of the drive shaft 37 and the like.

  As shown in FIG. 5, the gap between the upper support hole 33 (large diameter portion 33 a) and the outer peripheral surface of the driven shaft 35, and the lower support hole 34 (large diameter portion 34 a) and the drive shaft. The gap between the outer peripheral surface 37 and the outer peripheral surface 37 is divided into an inner side (a pump chamber 30 side) and an outer side by seal members 39 and 40, respectively. As shown in FIG. 1, a seal member 41 is also provided at a portion of the flange 29 through which the drive shaft 37 passes.

  In this embodiment, as shown in FIG. 1, the body 26 is provided with a first cleaning liquid for supplying thinner (cleaning liquid) to the outer portions of the seal members 39 and 40 in the support holes 33 and 34. A flow path 42 is provided. Each shaft 35, 37 has an inlet portion that opens at the center of the tip surface of each shaft 35, 37. The shaft 35, 37 extends rearward from the inlet portion to support each shaft. In-shaft cleaning liquid channels 43 and 44 are provided that open inside the seal members 39 and 40 in the holes 33 and 34.

  At the same time, the closing plate 28 is thinner with respect to the cleaning liquid flow paths 43 and 44 in the shafts at positions where the front end surfaces of the shafts 35 and 37 wrap around the inlets of the cleaning liquid flow paths 43 and 44 in the shafts. A second cleaning liquid channel 45 having cleaning liquid supply ports 45a and 45b for supplying a cleaning liquid) is provided. Furthermore, in this embodiment, the end portion (lower end portion in FIG. 1) of the first cleaning liquid flow path 42 and the start end portion (lower end portion in FIG. 1) of the second cleaning liquid flow path 45 are outside the pump chamber 30. The body 26 is connected to the housing 27 and the closing plate 28 by a communication passage 46 extending in the front-rear direction.

  As shown in FIG. 4, the first cleaning liquid channel 42 has an inlet port 42 a that opens at the upper surface of the body 26. The inlet port 42a is connected to the tip of the thinner supply path 21 so that high or low pressure thinner is supplied. As shown in FIG. 1, the first cleaning liquid channel 42 extends downward from the inlet port 42 a in the body 26 and opens outside the seal member 39 in the large-diameter portion 33 a of the upper support hole 33. . Further, it extends downward from the large-diameter portion 33 a, opens outside the seal member 40 in the large-diameter portion 34 a of the lower support hole 34, further extends downward from the large-diameter portion 34 a, and is located at the rear end of the communication passage 46 Connected to the department.

  The second cleaning liquid channel 45 extends upward from the front end portion of the communication path 46 in the closing plate 28 and branches backward at two points in the middle. One side (upper side) opens at a position corresponding to (wraps) the center part of the front end surface of the driven shaft 35 (inlet part of the in-shaft cleaning liquid flow path 43) in the rear surface of the closing plate 28, and the cleaning liquid supply port 45a. The other (lower side) of the branch paths opens at a position corresponding to (wraps) the center portion of the front end surface of the drive shaft 37 (inlet portion of the in-shaft cleaning liquid flow path 44) in the rear surface of the closing plate 28. Thus, the cleaning liquid supply port 45b is formed.

  The in-shaft cleaning liquid channel 43 provided on the driven shaft 35 extends rearward from the inlet opening at the center of the front end surface of the shaft 35 and is bent in the outer peripheral direction to be bent on the outer peripheral surface (upper part). An opening is formed at a position inside the seal member 39 of the large diameter portion 33a of the support hole 33. Further, the in-shaft cleaning liquid flow path 44 provided in the drive shaft 37 extends rearward from the inlet portion that opens at the center portion of the front end surface of the shaft 37, and is bent in the outer peripheral direction so as to be bent on the outer peripheral surface ( The lower support hole 34 is opened at a large diameter portion 34a (inner position of the seal member 40).

  Thus, the thinner supplied to the inlet port 42a through the thinner supply passage 21 passes through the first cleaning liquid passage 42 and is supplied to the outside of the seal member 39 in the large-diameter portion 33a of the upper support hole 33. Furthermore, the large diameter portion 34 a of the lower support hole 34 is supplied to the outside of the seal member 40. After that, it flows into the second cleaning liquid channel 45 through the communication path 46, passes through the cleaning liquid channel 44 in the shaft of the drive shaft 37 from the cleaning liquid supply port 45 b, and seal member of the large diameter portion 34 a of the lower support hole 34. 40 is supplied inside. At the same time, the cleaning liquid supply port 45 a of the second cleaning liquid flow path 45 passes through the in-shaft cleaning liquid flow path 43 of the driven shaft 35 and is supplied to the inside of the seal member 39 in the large diameter portion 33 a of the upper support hole 33. The thinner finally enters the pump chamber 30 through the side surfaces (rear end surfaces) of the gears 36 and 38 and is discharged from the discharge passage 32.

  Next, the operation of the above configuration will be described with reference to FIG. In the coating apparatus 11, during a normal painting operation (when the paint is transferred), the paint is supplied to the inlet port 31 a of the gear pump body 18 through the paint supply path 13 and the gear pump 16 (drive motor 19) is driven. Is done. At this time, the thinner adjusted to a low pressure is supplied to the inlet port 42 a of the gear pump body 18 through the thinner supply path 21. Thus, as shown in FIG. 5, the paint is sucked into the pump chamber 30 from the suction passage 31 and discharged from the discharge passage 32 by the rotation of the drive gear 38 and the driven gear 36, and is applied to the coating machine 17. Is supplied in a fixed amount.

  Here, the paints include, for example, UV curable paints that are highly reactive and easily cured, and fine pigments (solids) that are separated from the main agent. There is a kind that is easy to do. In the gear pump main body 18 described above, when such paint is transferred, the paint enters between the support holes 33 and 34 (large diameter portions 33a and 34a) and the shafts 35 and 37, and the hardening reaction of the paint due to friction. May be promoted to adhere to the shafts 35 and 37, or the pigment may adhere to the seal portion and wear the seal members 39 and 40 and the shafts 35 and 37. However, in this embodiment, such a problem can be prevented in advance by supplying thinner to the first cleaning liquid channel 42 and the like.

  That is, in the gear pump body 18, there is a risk that the paint or the like in the pump chamber 30 may enter the seal members 39 and 40 between the large diameter portions 33 a and 34 a and the shafts 35 and 37 when the paint is transferred. However, when thinner is supplied from the inlet port 42a at a low pressure, the thinner is passed through the first cleaning liquid flow path 42 to the outer portions of the seal members 39, 40 in the support holes 33, 34 (large diameter portions 33a, 34a). Thinner will be supplied. At this time, the pressure of the thinner supplied to the outer portions of the seal members 39 and 40 is set to be equal to or slightly larger than the pressure of the paint in the pump chamber 30, that is, the pressure of the inner portions of the seal members 39 and 40.

  Therefore, even if the paint in the pump chamber 30 and the solid matter (pigment, etc.) in the pump chamber 30 enter the inside of the seal members 39, 40, the outer circumferences of the shafts 35, 37 extend beyond the seal portions of the seal members 39, 40. Intrusion between the inner periphery of the support holes 33 and 34 can be prevented. As a result, it is possible to prevent the coating material from being hardened in the seal members 39 and 40 and the gaps between the shafts 35 and 37 and the support holes 33 and 34, and the pigment from being worn or damaged. Can do.

  Further, as shown in FIG. 5, the thinner supplied to the first cleaning liquid flow path 42 passes through the second cleaning liquid flow path 45 from the communication path 46 and passes through the in-shaft cleaning liquid flow path 44 of the drive shaft 37. The large diameter portion 34 a of the lower support hole 34 is supplied to the inside of the seal member 40, and the seal member 39 of the large diameter portion 33 a of the upper support hole 33 passes through the in-shaft cleaning liquid channel 43 of the driven shaft 35. Supplied inside. As a result, the paint that is about to enter the support holes 33 and 34, the pigment therein, and the like can be pushed out by the thinner and discharged to the pump chamber 30 side. Accordingly, the paint, pigment, and the like that are about to enter the support holes 33 and 34 always flow, and can be prevented from staying on the side surfaces of the support holes 33 and 34 and the gears 36 and 38.

  At this time, the thinner supplied to the inside of the seal members 39 and 40 through the in-shaft cleaning liquid channels 43 and 44 finally passes through the side surfaces (rear end surfaces) of the gears 36 and 38 to the pump chamber 30. It enters and is discharged from the discharge passage 32 together with the paint. Even if the thinner is supplied into the pump chamber 30 in this way, the supply amount is very small, so that the paint only needs to be slightly diluted, and can be done without adversely affecting the transferred paint.

  When the paint type (color) used for painting is changed (or at the end of the painting operation), the inside of the pump chamber 30 and the gears 36 and 38 (and the entire paint path) are cleaned with a cleaning liquid (thinner). A cleaning step is performed. At the time of this cleaning, the thinner adjusted to a high pressure is supplied to the inlet port 42 a of the gear pump body 18 through the thinner supply path 21. As a result, the high-pressure thinner passes through the first cleaning liquid flow path 42, the communication path 46, and the second cleaning liquid flow path 45 in order, and passes through the in-shaft cleaning liquid flow paths 43 and 44, thereby sealing members in the support holes 33 and 34. 39 and 40 are supplied to the inner part.

  Thus, the paint remaining in the inner portions of the seal members 39, 40 in the support holes 33, 34 and the pigments therein can be efficiently discharged from the support holes 33, 34 and cleaned. it can. The thinner supplied to the inside of the seal members 39 and 40 cleans the side surfaces of the gears 36 and 38 and the inner surface of the pump chamber 30 and is discharged from the discharge passage 32. At this time, by supplying the thinner to the first cleaning liquid flow path 42 with a sufficiently high pressure, the thinner is forcibly passed from the outside toward the inside by the seal members 39 and 40, and the seal is sealed. The portion (between the shafts 35 and 38 and the seal members 39 and 40) can be effectively cleaned.

  As described above, according to the gear pump 16 of the present embodiment, the seal members 39 and 40 are provided on the inner peripheral portions of the support holes 33 and 34 for supporting the driven shaft 35 and the drive shaft 37, respectively, and the support holes 33 are provided. , 34 for supplying thinner to the outer portions of the seal members 39, 40, and a cleaning liquid channel in the shaft that opens inside the seal members 39, 40 of the shafts 35, 37. 43 and 44 and the second cleaning liquid channel 45 for supplying thinner to each of the in-shaft cleaning liquid channels 43 and 44, the pigment is easily separated or the curing reaction is likely to occur. Even when the paint is transferred, it is possible to prevent a problem that occurs when the paint or the separated pigment enters between the outer periphery of the shafts 35 and 37 and the support holes 33 and 34. It exhibits an excellent effect that.

  In particular, in the present embodiment, the end portion of the first cleaning liquid channel 42 and the starting end portion of the second cleaning liquid channel 45 are connected by the communication path 46 located outside the pump chamber 30. Therefore, the flow path for supplying thinner to the first cleaning liquid flow path 42 and the second cleaning liquid flow path 45 may be a single system, and an advantage that the configuration can be simplified can be obtained. .

  In the above embodiment, the first cleaning liquid channel 42 and the second cleaning liquid channel 45 are connected by the communication path 46. However, the first cleaning liquid channel and the second cleaning liquid channel are connected to each other. It is good also as a structure which provides in another system and supplies a washing | cleaning liquid to each. In addition, the present invention is not limited to the above-described embodiments, such as various changes in the overall system configuration of the coating apparatus and the specific shape and structure of each part of the gear pump. The present invention can be implemented with appropriate modifications within a range that does not deviate.

  In the drawings, 11 is a coating device, 13 is a paint supply path, 16 is a gear pump, 17 is a coating machine, 18 is a gear pump body, 19 is a drive motor, 21 is a thinner supply path, 26 is a body, 27 is a housing, and 28 is closed. Plate, 30 is a pump chamber, 31 is a suction passage, 32 is a discharge passage, 33 and 34 are support holes, 33a and 34a are large diameter portions, 35 is a driven shaft, 36 is a driven gear, 37 is a drive shaft, 38 is a drive Gears 39 and 40 are seal members, 42 is a first cleaning liquid flow path, 43 and 44 are cleaning liquid flow paths in the shaft, 45 is a second cleaning liquid flow path, and 46 is a communication path.

Claims (2)

A body, a pump chamber formed by connecting a closing plate to the tip of the body, a suction passage and a discharge passage communicating with the pump chamber, and a rear wall of the pump chamber provided in the body. Two support holes extending toward the rear, two shafts rotatably supported by the respective support holes and having distal ends positioned in the pump chamber, and fitted to the outer circumferences of the distal ends of the shafts. A gear pump comprising two gears disposed in a chamber, wherein the gear rotates to suck liquid from the suction passage into the pump chamber and discharge from the discharge passage;
A seal member that provides a fluid-tight seal between the support hole and the outer peripheral surface of the shaft is provided on the inner peripheral portion of the opening end portion on the pump chamber side of each of the support holes. And the outside opposite to it are partitioned,
A first cleaning liquid flow path provided in the body for supplying a cleaning liquid to an outer portion of the seal member in each of the support holes;
A shaft that is provided on each shaft and has an inlet portion that opens at the center of the front end surface of the shaft, and that extends rearwardly from the inlet portion to the inside of the shaft and opens inside the seal member in each support hole An inner cleaning liquid flow path;
A second cleaning liquid flow path having a cleaning liquid supply port for supplying a cleaning liquid to the cleaning liquid flow path in the shaft is provided at a position provided on the closing plate and wrapping at an inlet portion of each shaft. Gear pump characterized by The terminal end of the first cleaning liquid flow path and the start end of the second cleaning liquid flow path are connected by a communication path located outside the pump chamber,
The cleaning liquid that has passed through the first cleaning liquid flow path flows through the communication path into the second cleaning liquid flow path and is supplied to the in-shaft cleaning liquid flow path. The gear pump according to claim 1.

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