Paint supply device

Abstract

To improve a paint supply device 1 regardless of a switching pattern from the air-driven type to the electrically-driven type of pumps for supply and replenishment.MEANS FOR SOLVING THE PROBLEM: A paint supply device 1 includes a first storage tank 3 and a second storage tank 4 for storing paint to be applied to a workpiece in a coating booth R2, supplies paint from the second storage tank 4 to the coating booth R2, and replenishes paint from the first storage tank 3 to the second storage tank 4. The paint supply device 1 includes a next electrically-driven type 5A and primary-side and secondary-side switching valves 5B, 5C. Namely, the pump 5A can suction and discharge the paint. The primary-side switching valve 5B is controlled to switch the suction source of the paint to the pump 5A between the first and second storage tanks 3, 4. The secondary-side switching valve 5C is controlled to switch the discharge destination of the paint from the pump 5A between the second storage tank 4 and the coating booth R2.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a paint supply device that supplies paint to a painting space. [Background technology]

[0002] Conventionally, for example, in a process of painting the body of a vehicle, a paint booth is provided to house a painting robot, and paint is supplied to the paint booth. Here, for example, an applicator unit that applies paint to the body as a workpiece is attached to the tip of the robot, and in the paint booth, painting of the workpiece is progressed while controlling the operation of the robot and the applicator unit.

[0003] In order to supply paint to a painting booth, for example, a paint supplying device including a storage tank and a pump as described below is known. That is, the storage tank is installed outside the painting booth to store paint, and the pump sucks paint from the storage tank and discharges it toward the painting booth (see, for example, Patent Document 1). Furthermore, such a paint supply device includes a pump for refilling the storage tank with paint, in addition to a pump for supplying paint to the painting booth. The refilling pump then sucks paint from a drum that stores, for example, about 40 liters of paint, and refills it into the storage tank.

[0004] Meanwhile, the supply and refill pumps used in paint supply devices are being replaced by electric pumps driven by electric motors, instead of the conventional air-driven pumps driven by air cylinders. As a result, paint supply devices installed in various places include a mix of pumps in which only one of the supply and refill pumps has been switched to an electric type, pumps in which both have been switched, and pumps in which neither have been switched. In view of the current state of such paint supply devices, there is a demand for new configurations that will improve the devices for any pattern. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 4938896 Summary of the Invention [Problem to be solved by the invention]

[0006] Therefore, an object of the present disclosure is to provide a paint supply device having a configuration that allows the device to be improved regardless of the switching pattern of the supply and replenishment pumps from air-driven to electric. [Means for solving the problem]

[0007] The paint supply device disclosed herein includes first and second storage tanks for storing paint to be applied to a workpiece in a designated painting space, and supplies paint from the second storage tank to the painting space and replenishes paint from the first storage tank to the second storage tank. The paint supply device further includes an electric pump and a primary / secondary switching valve.

[0008] That is, the electric pump is capable of sucking in and discharging paint. The primary-side switching valve is controlled to switch the source of paint sucked into the pump between the first and second storage tanks, and the secondary-side switching valve is controlled to switch the destination of paint discharged from the pump between the second storage tank and the painting area. As a result, according to the paint supply device of the present disclosure, the device can be improved regardless of the switching pattern of the supply and replenishment pumps to electric type. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a configuration diagram of a paint supply device. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] 13 is a side view showing the side surface of the movable part together with a part of the base part. FIG. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] 9 is a cross-sectional view taken along line IX-IX of FIG. 8. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the mode for carrying out the invention will be described based on examples. Note that the examples disclose specific examples, and it goes without saying that the present invention is not limited to the examples. EXAMPLES

[0011] [Configuration of Example 1] A paint supplying device 1 according to a first embodiment will be described with reference to the drawings. The paint supplying device 1 supplies paint used for painting, for example, the body of a vehicle, and supplies paint from, for example, a paint mixing room R1 to a painting space R2 (hereinafter, sometimes referred to as a painting booth R2) that houses a painting robot 2. Here, for example, a coating unit 2a such as a discharge gun that applies paint to the body as a workpiece is attached to the tip of the robot 2, and in the painting booth R2, painting of the workpiece is progressed while controlling the operation of the robot 2 and the coating unit 2a. The configuration of the paint supplying device 1 will be described in detail below.

[0012] The paint supplying device 1 includes first and second storage tanks 3 and 4 for storing paint to be applied to workpieces in a painting booth R2, and supplies paint from the second storage tank 4 to the painting booth R2 and replenishes paint from the first storage tank 3 to the second storage tank 4. The paint supplying device 1 further includes the following electric pump 5A, and primary and secondary side switching valves 5B and 5C which are attached to the primary and secondary sides of the pump 5A.

[0013] The pump 5A and the primary and secondary switching valves 5B and 5C are controlled in operation by control signals sent from a control panel 6 (hereinafter, the pump 5A and the primary and secondary switching valves 5B and 5C may be collectively referred to as the pump unit 5.) The first and second storage tanks 3 and 4, the pump 5A, the primary and secondary switching valves 5B and 5C, and the control panel 6 are housed in the blending chamber R1 described above.

[0014] First, the first storage tank 3 is a container capable of storing and transporting paint, for example, a drum can in which about 40 liters of paint is stored (hereinafter, the first storage tank 3 may be referred to as a drum can 3). The drum can 3 is carried into the blending room R1 and placed in a predetermined position, and paint is replenished from the drum can 3 to the second storage tank 4. When the remaining amount of paint in the drum can 3 falls below a predetermined amount, it is carried out of the blending room R1, and a new drum can 3 with a sufficiently large remaining amount of paint is carried into the blending room R1 and used.

[0015] Here, the drum can 3 is an open drum type with a detachable top lid, and is placed in a predetermined position as the first storage tank 3, and the top lid is removed. Thereafter, the liquid level formed inside the drum can 3 is covered with another top lid 7, which will be described later, and the paint is sucked through a pipe 8 provided in the top lid 7. The top lid 7 is pulled up each time the drum can 3 is replaced with a new one, and is reused repeatedly.

[0016] A replenishment flow path F1 for replenishing paint to the second storage tank 4 is connected to the drum 3. The replenishment flow path F1 is set to flow from the drum 3 to the second storage tank 4 via the pump unit 5. Here, in the replenishment flow path F1, the section between the drum 3 and the pump unit 5, and the section between the pump unit 5 and the second storage tank 4 are respectively constituted by hoses 9a, 9b. Both hoses 9a, 9b are, for example, Teflon hoses whose outsides are covered with stainless steel flexible tubes ("Teflon" is a registered trademark).

[0017] As described above, the piping 8 is integrally provided on the top lid 7, and passes through the top lid 7. The refill flow path F1 is connected to the drum 3 by setting the top lid 7 on the top of the drum 3 and connecting a hose to the upper end of the piping 8. The lower end of the piping 8 is inserted into the paint inside the drum.

[0018] Next, the second storage tank 4 is a tank installed in the blending room R1, and this tank is, for example, a cylindrical vertical type with a cone-shaped lower portion that narrows toward the bottom (hereinafter, the second storage tank 4 may be referred to as tank 4). Further, the tank 4 is connected to the refilling flow path F1, as well as to the next supply flow path F2 and return flow path F3.

[0019] First, the supply flow path F2 is a flow path for supplying paint from the tank 4 to the painting booth R2. The supply flow path F2 is set to run from the bottom of the tank 4 through the pump unit 5 and the filter unit 10 toward the paint booth R2. Here, the filter unit 10 is for removing foreign matter from the paint heading toward the painting booth R2, and includes a well-known filter body 10a, two-way valves 10b1, 10b2 that are manually opened and closed on the primary and secondary sides of the filter body 10a, and pressure gauges 10c1, 10c2 that display the pressure on the primary and secondary sides of the filter body 10a.

[0020] In addition, in the supply flow path F2, the portion between the tank 4 and the pump unit 5, and the portion between the pump unit 5 and the filter unit 10 are respectively constituted by hoses 9c and 9d. Note that both of the hoses 9c and 9d are Teflon hoses covered on the outside with a stainless steel flexible pipe. Furthermore, in the supply flow path F2, the portion from the filter unit 10 toward the coating booth R2 is constituted by, for example, stainless steel piping p1.

[0021] A manual three-way valve 4a is attached to the bottom of the tank 4, and the supply flow path F2 is connected to the tank 4 by connecting a hose 9c to one of the three ports of the three-way valve 4a. Of the remaining two ports of the three-way valve 4a, one port opens to the inside of the tank 4, and the other port is open to the atmosphere.

[0022] Next, the return flow path F3 is a flow path for returning the paint to the tank 4 from the painting booth R2. Furthermore, the return flow path F3 is set to flow from the coating booth R2 to the tank 4 via the back pressure control unit 11. Here, the back pressure control unit 11 controls the paint discharge pressure in the application section 2a, and includes, for example, a well-known pressure relief valve 11a that is manually operated by an operator, a two-way valve 11b that is manually opened and closed on the primary side of the pressure relief valve 11a, and a pressure gauge 11c that displays the pressure of the pressure relief valve 11a.

[0023] In addition, the portion of the return flow path F3 between the back pressure control unit 11 and the tank 4 is configured with a hose 9e. The hose 9e is also a Teflon hose covered with a stainless steel flexible tube on the outside. Furthermore, in the return flow path F3, the portion from the painting booth R2 toward the back pressure control unit 11 is configured with, for example, a stainless steel pipe p2.

[0024] A manual three-way valve 4b is also attached to a position near the bottom end of the cylindrical portion of the tank 4, and the return flow path F3 is connected to the tank 4 by connecting a hose 9e to one of the three ports of the three-way valve 4b. Of the remaining two ports of the three-way valve 4b, one port opens into the inside of the tank 4 via a flat spray nozzle 4c, and the other port is open to the atmosphere. The refilling passage F1 is connected to the tank 4 by connecting a hose 9b to a pipe 4d that penetrates the top lid of the tank 4.

[0025] In addition to the above-mentioned piping 4d, the top lid of the tank 4 is also integrated with the following agitator 4e and level gauge 4f. First, the agitator 4e is composed of an agitator blade 4ea that is immersed in the paint in the tank 4, and a drive unit 4eb that drives and rotates the agitator blade 4ea. The level gauge 4f detects the level of the paint in the tank 4. The level gauge 4f is a well-known capacitance type level sensor.

[0026] The agitator 4e is integrated with the top cover in the following manner: A drive unit 4eb is mounted on the top cover, and a rotation output shaft 4ec of the drive unit 4eb passes through the top cover and extends downward. An agitator blade 4ea is attached to the tip of the rotation output shaft 4ec. Furthermore, the level gauge 4f is integrated with the top lid in the following manner: That is, the main body 4fa is mounted on the top lid, and the detection section 4fb extends downward through the top lid.

[0027] Next, the pump unit 5 will be described in detail. The pump unit 5 sucks paint from either the drum 3 or the tank 4, and discharges the sucked paint toward either the painting booth R2 or the tank 4, and has the following pump 5A and primary and secondary side switching valves 5B and 5C.

[0028] First, the pump 5A is an electric diaphragm pump of known structure, and the primary and secondary switching valves 5B and 5C are both electromagnetic three-way valves of known structure. One port of the primary and secondary switching valves 5B and 5C is connected to the suction port and discharge port of the pump 5A, respectively.

[0029] Further, hoses 9a and 9c are connected to the remaining two ports of the primary side switching valve 5B, and hoses 9b and 9d are connected to the remaining two ports of the secondary side switching valve 5C, respectively. This results in a configuration in which the pump unit 5 is incorporated in the middle of the refill flow path F1 and the supply flow path F2.

[0030] The pump 5A is started or stopped by a control signal sent from the control panel 6. The primary-side switching valve 5B switches the communication destination of the suction port of the pump 5A between hoses 9a and 9c by a control signal sent from the control panel 6. Therefore, the primary-side switching valve 5B is controlled to switch the suction source of the paint to the pump 5A between the drum 3 and the tank 4. The secondary-side switching valve 5C switches the communication destination of the discharge port of the pump 5A between hoses 9b and 9d by a control signal sent from the control panel 6. Therefore, the secondary-side switching valve 5C is controlled to switch the discharge source of the paint from the pump 5A between the tank 4 and the painting booth R2.

[0031] With this configuration, by operating the control panel 6, the supply of paint to the painting booth R2 and the replenishment of paint to the tank 4 can be performed as follows. That is, the primary side switching valve 5B switches the suction port of the pump 5A to the hose 9c, and the secondary side switching valve 5C switches the discharge port of the pump 5A to the hose 9d, and the pump 5A is started. This allows paint to be supplied from the tank 4 to the painting booth R2 through the supply flow path F2.

[0032] In addition, the primary-side switching valve 5B switches the suction port of the pump 5A to the hose 9a, and the secondary-side switching valve 5C switches the discharge port of the pump 5A to the hose 9b, and the pump 5A is started. This allows paint to be replenished from the drum 3 to the tank 4 through the replenishment flow path F1.

[0033] Moreover, the paint supplying device 1 includes an auxiliary unit 12 as described below. That is, the auxiliary part 12 assists in pulling the weight 14 described below upward by the load of the constant load spring 13. Here, in addition to the above-mentioned piping 8, the following agitator 16 and level gauge 17 are integrated into the top lid 7, and the weight 14 is composed of the top lid 7, piping 8, agitator 16, level gauge 17, etc.

[0034] The agitator 16 is made up of an agitator blade 16a that is immersed in the paint in the drum 3, and a drive unit 16b that rotates and drives the agitator blade 16a. The level gauge 17 detects the level of the paint in the drum 3, and is, for example, a well-known capacitance type level sensor.

[0035] The auxiliary unit 12 will be described in detail below (see Figures 2 to 9: for the sake of convenience and to avoid complexity, in Figures 2 to 9, the agitator 16 of the weight body 14 is shown, but the piping 8 and the level gauge 17 are not shown). First, the auxiliary portion 12 has a next holding portion 20 and a constant force spring 13 . That is, the holding portion 20 holds the top lid 7, and the constant load spring 13 is set so that a load acts on the holding portion 20 in an upward direction, and the load of the constant load spring 13 assists in pulling the weight body 14 upward.

[0036] The top cover 7 is a metal member having a circular portion 7a facing the liquid surface, and a short cylindrical portion 7b extending from the periphery of the circular portion 7a to one side and covering the outer circumferential surface near the upper end of the drum can 3. The piping 8 is integrated with the circular portion 7a so as to pass vertically through it (see FIG. 1).

[0037] The agitator 16 is integrated with the top cover 7 in the following manner. That is, the drive unit 16b is mounted on the circular portion 7a, and the rotation output shaft 16c of the drive unit 16b penetrates the circular portion 7a and extends downward. The agitator blade 16a is attached to the tip of the rotation output shaft 16c. Furthermore, the level gauge 17 is integrated with the top cover 7 in the following manner: That is, the main body portion 17a is mounted on the circular portion 7a, and the detection portion 17b extends downward through the circular portion 7a.

[0038] Furthermore, metallic fastening members 21 used to fasten the weight body 14 and the holding portion 20 are attached to the cylindrical portion 7b of the upper cover 7 at two locations spaced apart by an angle of 180°. Next, the configuration of the auxiliary unit 12 will be described.

[0039] The auxiliary section 12 is roughly divided into a movable section 23 and a base section 24 . First, the movable part 23 is a part that includes the holding part 20 and moves up and down while holding the weight body 14, and has the drawn-out end 13a of the constant force spring 13 fixed thereto (see Figs. 5, 7, 8, etc.). Next, the base part 24 is a part that guides the up and down movement of the movable part 23 and is placed on a predetermined installation surface, and has the drum 13b around which the constant force spring 13 is wound fixed thereto (see Figs. 2, 6, 8, etc.). The movable portion 23 and the base portion 24 will be described below in turn.

[0040] First, the movable portion 23 includes the above-mentioned holding portion 20, as well as a lower extension portion 26 and a slide portion 27 (see FIGS. 2, 4, 5, 6, 7, etc.). The holding portion 20 holds the weight body 14 and is, for example, a metal part that appears U-shaped when viewed from above (see Figure 3). It has two arms 20a, a connecting portion 20b connecting the ends of the arms 20a, and two bridging portions 20c that cross-bridge between each of the arms 20a and the connecting portion 20b.

[0041] In the following description, the side where the arm 20a protrudes from the connection part 20b is defined as the front, and the side where the arm 20a does not protrude is defined as the rear, and the left and right are defined when viewing the holding part 20 from the front. In addition, the two arms 20a may be referred to as the left and right arms 20aL and 20aR, respectively.

[0042] When viewed from above, the weight body 14 is held within a range defined by the arms 20aL, 20aR, the connecting portion 20b, and the two bridging portions 20c. Here, the fastening members 21 are metal bodies having an inverted L-shaped cross section, and engage with the arms 20aL, 20aR from inside the range in which the weight body 14 is housed (hereinafter, the left and right fastening members 21 may be referred to as fastening members 21L, 21R).

[0043] Next, the manner in which the weight body 14 is held by the holding portion 20 will be described. First, the weight body 14 is held by the holding part 20 by fastening a slider 21a with a well-known screw hole to a screw 21b (see Figs. 2, 3, 5, etc.). That is, a slide groove 21c that allows the slider 21a to move freely is provided on the upper part of each of the arms 20aL and 20aR along the longitudinal direction of the arms 20aL and 20aR. Also, an elongated hole 21d that runs along the longitudinal direction of the arm is provided on the upper side of the fastening member 21.

[0044] Then, the slider 21a is moved to a desired position, and the weight body 14 is moved as a whole while engaging the fastening members 21L, 21R with the arms 20aL, 20aR, respectively, to match the position of the slider 21a, so that the screw hole of the slider 21a is aligned with the long hole 21d of the fastening member 21. Then, the screw 21b is screwed into the slider 21a, sandwiching a part of the arms 20aL, 20aR and a part of the fastening members 21L, 21R between the claw of the slider 21a and the head of the screw 21b. As a result, the fastening members 21L, 21R are fastened to the arms 20aL, 20aR, respectively, and the weight body 14 is held by the holding part 20.

[0045] The lower extensions 26 have the function of securing a space for placing the drum 3 below the weight body 14. More specifically, the lower extensions 26 are two rod-shaped metal bodies assembled to extend downward from between the connection portion with the arm 20aL and the connection portion with the arm 20aR of the connection portion 20b (see Figures 2, 3, 5, 7, etc. Hereinafter, the left and right lower extensions 26 may be referred to as the lower extensions 26L and 26R, respectively).

[0046] Further, a rectangular annular metal plate 28 is fixed near the lower ends of the lower extensions 26L, 26R (see FIGS. 2, 5, 6, 7, 8, etc.). Specifically, the left and right sides 28L, 28R of the metal plate 28 are fixed to the lower extensions 26L, 26R, respectively, and the lower extensions 26L, 26R are bridged by the upper and lower sides 28U, 28D.

[0047] Furthermore, the drawn-out end 13a of the constant force spring 13 is fixed to the upper side portion 28U of the metal plate 28. Therefore, the weight body 14 is held by the holding portion 20 above the drawn-out end 13a, and a space according to the length of the lower extension portions 26L, 26R can be secured below the weight body 14. The lower extensions 26L and 26R are bridged to the left and right ends of the connecting portion 20b by bridge portions 26a, respectively.

[0048] The slide portion 27 is attached to a guide portion 30 provided on the base portion 24 so as to be movable up and down, and as described later, has a function of stabilizing the up and down movement of the weight body 14 together with the guide portion 30. The slide portion 27 will be described in detail later together with the guide portion 30.

[0049] Next, the base portion 24 includes a frame body 31 and a guide portion 30 (see FIGS. 2, 3, 4, 6, 8, 9, etc.). The frame 31 is a part that forms the framework of the base portion 24, and has left and right pillar portions 31pL, 31pR, upper and lower bridge portions 31bU, 31bD, left and right forward protrusions 31FL, 31FR, and left and right rearward protrusions 31BL, 31BR. Here, the pillar portions 31pL and 31pR are portions that extend vertically.

[0050] The upper bridge portion 31bU is a portion that bridges the upper ends of the pillar portions 31pL and 31pR, and the lower bridge portion 31bD is a portion that bridges the lower ends of the pillar portions 31pL and 31pR. The lower bridge portion 31bD is longer than the upper bridge portion 31bU, and the left end of the lower bridge portion 31bD protrudes leftward from the pillar portion 31pL, and the right end of the lower bridge portion 31bD protrudes rightward from the pillar portion 31pR. The lower bridge portion 31bD and the connection portion 20b of the holding portion 20 have the same length in the left-right direction, and the arm 20aL is located to the left of the pillar portion 31pL and the arm 20aR is located to the right of the pillar portion 31pR (see FIG. 2, FIG. 3, etc.).

[0051] A drum 13b wound with a constant force spring 13 is attached to the upper bridge portion 31bU via a predetermined metal fitting 32 (see Figs. 2, 8, etc.). Here, the drum 13b is attached so that its axial direction faces the left-right direction, and is attached to the center of the upper bridge portion 31bU in the left-right direction.

[0052] Two constant force springs 13 and two drums 13b are provided, and the two constant force springs 13 are arranged in parallel on the left and right and set between the upper bridge portion 31bU and the metal plate 28 (hereinafter, the left and right constant force springs 13 may be referred to as constant force springs 13L and 13R, respectively. Furthermore, the left and right drums 13b may be referred to as drums 13bL and 13bR, respectively).

[0053] The forward protrusions 31FL and 31FR are portions extending forward from the lower bridge portion 31bD, the forward protrusion 31FL extending from the left end of the lower bridge portion 31bD, and the forward protrusion 31FR extending from the right end of the lower bridge portion 31bD (see Figs. 2, 8, 9, etc.). The rearward protrusions 31BL and 31BR are portions extending backward from the lower bridge portion 31bD, the rearward protrusion 31BL extending from a position to the right of the left end of the lower bridge portion 31bD, and the rearward protrusion 31BR extending from a position to the left of the right end of the lower bridge portion 31bD (see Figs. 3, 9, etc.). The rearward protrusions 31BL and 31BR are shorter than the forward protrusions 31FL and 31FR.

[0054] Furthermore, the column 31pL is cross-bridged by the lower bridging portion 31bD and the rear protruding portion 31BL via the bridging portion 31C, and the column 31pR is cross-bridged by the lower bridging portion 31bD and the rear protruding portion 31BR via the bridging portion 31C (see Figures 2, 3, 4, 8, 9, etc.).

[0055] In addition, bridging portion 31C between column 31pL and lower bridging portion 31bD bridges column 31pL and lower bridging portion 31bD to the left of the root of rear protrusion 31BL, and bridging portion 31C between column 31pR and lower bridging portion 31bD bridges column 31pR and lower bridging portion 31bD to the right of the root of rear protrusion 31BR. The lower bridge portion 31bD, the forward protrusions 31FL, 31FR, and the rearward protrusions 31BL, 31BR are placed directly on the installation surface.

[0056] Next, the guide portion 30, together with the slide portion 27, has the function of stabilizing the vertical movement of the weight body 14 (see Figs. 5, 6, 7, 8, etc.). First, the guide portion 30 is two cylindrical metal rods that are vertically spanned between the upper and lower bridge portions 31bU and 31bD, and the upper and lower ends of the metal rods are fixed to the upper and lower bridge portions 31bU and 31bD by predetermined metal fittings 33 (hereinafter, the left and right guide portions 30 may be referred to as guide portions 30L and 30R, respectively.) The guide portion 30L is provided between the pillar body 31pL and the drum 13bL, and the guide portion 30R is provided between the pillar body 31pR and the drum 13bR.

[0057] On the other hand, the slide portion 27 is a metal body having a cylindrical hollow 27h, and one slide portion 27 is fixed to each of the four corners of the metal plate 28. Therefore, the pull-out ends 13a of the constant force springs 13L, 13R and the slide portions 27 at the upper two corners are at the same height in the vertical direction. Also, a bush 27b is provided in the hollow 27h of each slide portion 27, and the slide portion 27 is guided by the guide portion 30 via the bush 27b (hereinafter, the upper left, upper right, lower left, and lower right slide portions 27 may be referred to as slide portions 27LU, 27RU, 27LD, and 27RD, respectively).

[0058] Here, the lower extension portion 26L, the side portion 28L of the metal plate 28, the slide portions 27LU, 27LD and the guide portion 30L are arranged at approximately the same position in the left-right direction, and the lower extension portion 26R, the side portion 28R of the metal plate 28, the slide portions 27RU, 27RD and the guide portion 30R are also arranged at approximately the same position in the left-right direction.

[0059] The two left slide portions 27LU, 27LD are guided by guide portion 30L, and the two right slide portions 27RU, 27RD are guided by guide portion 30R. Additionally, the upward movement of the entire movable part 23 is restricted by the fact that the slide parts 27LU and 27RU are each locked by the upper metal fittings 33. When the upward movement of the movable part 23 is restricted, the two pull-out ends 13a are slightly pulled out downward from the state in which they are wound around the drums 13bL and 13bR, respectively.

[0060] Therefore, throughout the entire movable range of the movable part 23, the constant load springs 13L, 13R apply a load upward to the holding part 20, and the auxiliary part 12 can assist in pulling the weight body 14 upward by the load of the constant load springs 13L, 13R.

[0061] Here, an example of how to use the auxiliary unit 12 will be described. First, the movable part 23 is moved upward to pull the holding part 20 and the weight body 14 upward, and a space is secured below the top lid 7 to place the drum 3. Next, a new drum 3 containing paint is brought under the weight body 14, and the top lid of the drum 3 is removed to expose the paint liquid surface at the top. Next, the movable part 23 is moved downward to cover the liquid surface with the top lid 7, and the agitator 16a and the like are inserted into the drum 3. Then, the driver 16b is operated to rotate the agitator 16a.

[0062] [Effects of the embodiment] The paint supplying device 1 of the embodiment includes first and second storage tanks 3 and 4 for storing paint to be applied to workpieces in a painting booth R2, and supplies paint from the second storage tank 4 to the painting booth R2 and replenishes paint from the first storage tank 3 to the second storage tank 4. The paint supplying device 1 also includes the following electric pump 5A and primary and secondary side switching valves 5B and 5C.

[0063] That is, the pump 5A is capable of sucking in and discharging paint. The primary-side switching valve 5B is controlled to switch the source of paint sucked into the pump 5A between the first and second storage tanks 3 and 4, and the secondary-side switching valve 5C is controlled to switch the destination of the paint discharged from the pump 5A between the second storage tank 4 and the painting booth R2.

[0064] As a result, according to the paint supply device 1, the device can be improved regardless of the switching pattern from air-driven to electric-driven supply and replenishment pumps, which have conventionally existed separately. In other words, in a case where only one of the supply and replenishment pumps has been switched to an electrically operated type, the pump that has been switched to an electrically operated type can be used as pump 5A as is, and primary and secondary side switching valves 5B and 5C can be attached to the suction and discharge sides of pump 5A, respectively, thereby improving the device by eliminating the air-driven pump.

[0065] In addition, in a pattern in which both pumps are switched, the device can be improved by omitting one of the pumps and employing the other pump as pump 5A, and installing primary and secondary side switching valves 5B and 5C on the suction side and discharge side of pump 5A, respectively.

[0066] Furthermore, in a pattern where neither pump is switched, the device can be improved by omitting both pumps and installing a new electric pump 5A and installing primary and secondary side switching valves 5B and 5C on the suction and discharge sides of pump 5A, respectively. This allows the device to be improved regardless of the switching pattern from air-driven to electric-driven supply and replenishment pumps.

[0067] According to the paint supply device 1 of the embodiment, the first storage tank 3 is a drum 3 that can store and transport paint, and when the remaining amount of paint becomes less than a predetermined amount, it is replaced with a new product having a remaining amount of paint greater than the predetermined amount. This allows the second storage tank 4 to continue to be replenished with paint.

[0068] The paint supplying device 1 of the embodiment includes an auxiliary unit 12 having a holding unit 20 and a constant load spring 13 as described below. That is, the holding unit 20 holds the top lid 7 that covers the surface of the paint inside the drum 3. The constant load spring 13 is set so that a load acts upward on the holding unit 20. The auxiliary unit 12 assists in pulling the top lid 7 upward by the load of the constant load spring 13.

[0069] This provides a countermeasure that does not impose a large burden on the operator when lifting the top cover 7 upward and does not require large-scale equipment. That is, the constant force spring 13 has a constant force (load) returning to the drum 13b regardless of the amount of pull-out of the pull-out end 13a. As a result, when the top lid 7 is lifted upward, a constant load always acts upward regardless of the height of the top lid 7. Therefore, the top lid 7 can be easily lifted upward without imposing a large load on the operator and without requiring large-scale equipment.

[0070] According to the paint supply device 1 of the embodiment, the following piping 8, agitator 16, and level gauge 17 are integrated into the top cover 7. That is, the agitator 16 has an agitator blade 16a that agitates the paint to form the liquid surface, and a drive unit 16b that rotates and drives the agitator blade 16a. The piping 8 is provided to replenish the paint from the drum 3 to the second storage tank 4, and the level gauge 17 detects the liquid surface inside the drum 3. This makes it possible to obtain the effect of the auxiliary portion 12 more significantly.

[0071] [Modifications] The present invention can be modified in various ways without departing from the spirit and scope of the invention. For example, according to the paint supply device 1 of the embodiment, paint is supplied from the tank 4 to the painting booth R2 by switching the connection of the suction port of the pump 5A to the hose 9c at the primary side switching valve 5B and switching the connection of the discharge port of the pump 5A to the hose 9d at the secondary side switching valve 5C and starting the pump 5A, but paint may also be supplied from the drum 3 to the painting booth R2 by switching the connection of the suction port of the pump 5A to the hose 9a at the primary side switching valve 5B.

[0072] In addition, by switching the connection of the secondary side switching valve 5C to the hose 9b, the supply of paint from the tank 4 to the painting booth R2 can be stopped and the paint can be circulated between the tank 4 and the pump 5A. [Explanation of symbols]

[0073] 1 Paint supply device 3 Drum (first storage tank) 4 Tank (second storage tank) 5A Pump 5B Primary side switching valve 5C Secondary side switching valve R2 Paint booth (painting space)

Claims

1. A paint supplying device comprising first and second storage tanks for storing paint to be applied to a workpiece in a predetermined coating space, supplying paint from the second storage tank to the coating space and replenishing paint from the first storage tank to the second storage tank, An electric pump capable of sucking and discharging paint; a primary side switching valve that is controlled to switch the source of paint suction to the pump between the first and second storage tanks; a secondary side switching valve that is controlled to switch the destination of the paint discharged from the pump between the second storage tank and the painting space.

2. 2. The paint supply device according to claim 1, The first storage tank is a container that can store and transport paint, and when the remaining amount of paint becomes less than a predetermined amount, it is replaced with a new product having a remaining amount of paint greater than the predetermined amount.

3. 3. The paint supply device according to claim 2, A paint supply device comprising: a holding portion that holds a top lid that covers the liquid surface of the paint formed inside the container; and an auxiliary portion that has a constant load spring set to apply a load upward to the holding portion, and that assists in pulling the top lid upward by the load of the constant load spring.

4. 4. The paint supply device according to claim 3, A paint supply device characterized in that the upper cover is integrated with an agitator having an agitator blade that agitates the paint that forms the liquid surface, and a drive unit that rotates the agitator blade.

5. 4. The paint supply device according to claim 3, A paint supplying device according to claim 1, wherein the upper lid is integrally provided with a pipe for refilling the second storage tank with paint from the container.

6. 4. The paint supply device according to claim 3, A paint supplying device characterized in that a level gauge for detecting the liquid level is integrated into the upper cover.

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