Pump assembly for cooling a hydraulic system

Abstract

We provide a pump assembly for cooling a hydraulic system. [Solution] The present invention relates to a pump assembly comprising a motor and a hydraulic device, particularly for painting fluids, wherein the motor comprises an air inlet, the hydraulic device comprises at least one pump system, the motor is capable of driving at least one pump system by the hydraulic system, the pump assembly comprises at least one air passage arranged to allow heat exchange between the hydraulic system and at least one air passage, the at least one air passage is capable of being supplied with air by an air source (68), and the at least one air passage is fluidically connected to an air inlet (18) of the motor on the opposite side of the air source (68).

Description

Technical Field

[0001] The present invention relates to a pump assembly comprising a motor, a piston and a pump, particularly for a coating fluid, the piston being driven by the motor and thereby arranged to drive the pump by means of a hydraulic system.

Background Art

[0002] The motor is, for example, an air motor, the pump is, for example, a diaphragm pump having two diaphragms, and the hydraulic system corresponds to a drive system having oil.

[0003] For example, the motor operates at a maximum speed of 300 cycles per minute. This can on the one hand cause heating of the hydraulic system, which can change the viscosity in the hydraulic system, here the oil, and on the other hand cause cooling of the motor, which can lead to frosting on the motor.

[0004] German Patent No. 10318004 describes the addition of a practically closed outer enclosure surrounding the pump. The exhaust air from the motor is exhausted into the outer enclosure in order to cool the pump.

[0005] The system has an adjustable flap for changing the direction of part of the exhaust air towards the outside.

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the exhaust air from the motor can vary, which requires a certain adjustment, particularly by means of an adjustable flap.

[0007] Furthermore, the adjustable flap only allows reducing the amount of exhaust air received for cooling and thus reducing the cooling effect.

[0008] There is no adjustment system in case the cooling is not sufficient.

[0009] Ultimately, this does not prevent frost from forming on the motor.

[0010] Therefore, an object of the present invention is to propose a pump assembly that cools the hydraulic system and heats the motor so as not to change due to the operation of the pump assembly. [Means for solving the problem]

[0011] For this purpose, the present invention relates to a pump assembly comprising a motor and a hydraulic device, particularly for paint fluids, wherein the motor comprises an air inlet, the hydraulic device comprises at least one pump system, the motor is capable of driving at least one pump system by the hydraulic system, the pump assembly comprises at least one air passage arranged to allow heat exchange between the hydraulic system and at least one air passage, the at least one air passage is capable of being supplied with air by an air source, and the at least one air passage is fluidically connected to the air inlet of the motor on the opposite side of the air source.

[0012] The air supplied by the air source is not altered by the motor's exhaust function. The air cools the hydraulic system, is heated by the hydraulic system, and is then supplied to the motor to heat it. Finally, the cooling of the hydraulic system and the heating of the motor are adapted to the use of the pump.

[0013] According to another advantageous aspect of the present invention, the pump assembly, either alone or in any technically possible combination, comprises one or more of the following features:

[0014] The air source is a compressed air source, specifically compressed air from a compressor.

[0015] The pump assembly is a diaphragm pump, and the hydraulic system extends between the piston of the hydraulic system and the diaphragm or between each diaphragm, and the hydraulic system is preferably filled with oil.

[0016] The assembly comprises a pump body, and at least one air passage is directly defined in the pump body.

[0017] The hydraulic system comprises, for example, at least one conduit filled with oil, the conduit extending particularly between the piston of the hydraulic device and at least one diaphragm of the pump.

[0018] Each air passage comprises at least one conduit section or an air passage ring extending around each conduit section.

[0019] The above ring or each ring has an inner wall and an outer wall, air circulates between the inner wall and the outer wall, and the inner wall and / or outer wall are corrugated.

[0020] The above-mentioned ring or each of the rings has an inlet and an outlet, and the inlet and outlet of the above-mentioned ring or each of the rings are directly opposite each other.

[0021] The above-mentioned ring or each of the rings is provided with an inlet and an outlet, and the inlet and outlet of the above-mentioned ring or each of the rings are offset in a direction parallel to the central axis of the ring.

[0022] The assembly comprises two air passages, each having an inlet and an outlet. The inlet of the first air passage can be fluidly connected to an air source so that an air source supplies air to the first air passage. The outlet of the first air passage is connected to the inlet of the second air passage, and the outlet of the second air passage is connected to the air inlet of the motor.

[0023] The assembly includes two air passages, each air passage having an inlet and an outlet. The inlets of the two air passages can be fluidly connected to an air source such that the air source supplies air to the air passages, and the outlets of the air passages are connected to the air inlet of the motor.

Brief Description of the Drawings

[0024] The present invention will become more apparent by reading the following description, which is shown only by way of non-limiting examples with reference to the drawings. [Figure 1] FIG. 1 is a cross-sectional view of a pump assembly according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view of the pump assembly of FIG. 1 taken along plane II. [Figure 3] FIG. 3 is a cross-sectional view of the pump assembly of FIG. 1 taken along plane III. [Figure 4] FIG. 4 is a schematic diagram of air circulation in a first alternative pump assembly of the present invention. [Figure 5] FIG. 5 is a schematic diagram of air circulation in a second alternative pump assembly of the present invention.

Modes for Carrying Out the Invention

[0025] The pump assembly 10 according to an embodiment of the present invention is represented in FIGS. 1 to 3, except for certain connections that will be described in detail later with reference to FIGS. 4 and 5.

[0026] The pump assembly 10 is for a coating fluid, for example, paint.

[0027] The pump assembly 10 includes a motor 12 and a hydraulic device 16.

[0028] For example, the motor 12 is an air motor, particularly compressed air.

[0029] The motor 12 includes an air inlet 18 represented in FIGS. 4 and 5.

[0030] For example, a motor can operate at a maximum of 300 cycles per minute.

[0031] The motor 12 has an exhaust outlet (not shown), which is open to the external environment, particularly away from the pump 16 or the air passage described below.

[0032] The motor 12 can be displaced by driving the motor piston 14 provided in the motor 12, particularly in translational movement.

[0033] The piston 14 is positioned in the cylinder 24 such that it defines the first chamber 26 and the second chamber 28 in the cylinder 24.

[0034] The first chamber 26 extends towards the motor, while the second chamber 28 extends towards the pump 16.

[0035] Each of the chambers 26 and 28 is alternately supplied with air, in this case compressed air, by the motor 12, such that the motor piston 14 is periodically displaced by translation in the cylinder 24, particularly between a first position where the volume of the first chamber 26 is minimum and a second position where the volume of the first chamber 26 is maximum.

[0036] The hydraulic device 16 includes a hydraulic piston 22.

[0037] The hydraulic piston 22 is connected to the motor piston 14 via a pin 20.

[0038] This makes it possible to separate the motor 12 and the hydraulic device 16, for example, for maintenance.

[0039] The hydraulic piston 22 can be displaced together with the motor piston 14 by translational movement in the same direction.

[0040] The hydraulic piston 22 extends from the piston 14 on the opposite side of the first chamber 26.

[0041] The hydraulic piston 22 extends in the body, in this case the pump body described below, facing at least one pump system of the pump.

[0042] The main body has a hole 30 provided for receiving the hydraulic piston 22 on the opposite side of the motor piston 14.

[0043] The hydraulic piston 22 here comprises a central portion 32 and at least one side portion 34, 36 adjacent to the central portion 32, and here it comprises two side portions 34, 36 on either side of the central portion 32.

[0044] For example, the central portion 32 is formed in this case by two interdependent components.

[0045] The central portion 32 has an outer diameter that is strictly larger than the outer diameter of the side portions or each of the side portions 34.

[0046] This acts as a pressure amplifier.

[0047] The hydraulic piston 22 here consists of a pin 20, a central part 32, and two side parts 34 and 36.

[0048] The hydraulic device 16 has a fluid product inlet 48 in the painted product, and the pump 10 can pump up the fluid product.

[0049] The hydraulic device 16 comprises at least one pump system 50, in this case two pump systems.

[0050] Pump 10 is a diaphragm pump.

[0051] In particular, each pump system 50 is equipped with a diaphragm 52.

[0052] Each pump system includes a housing 56 in which a diaphragm 52 is located.

[0053] The housing 56 is separated into a product volume section 58 and a drive volume section 60 by a diaphragm 52.

[0054] The product volume section 58 and the drive volume section 60 are not in fluid communication.

[0055] The product volume section 58 is supplied with the fluid product through the inlet 48 and has an outlet.

[0056] When the displacement of the diaphragm 52 increases the volume of the product volume section 58, the fluid product is drawn into the product volume section 58 via the inlet 48. When the displacement of the diaphragm 52 decreases the volume of the product volume section 58, the fluid product is discharged from the outlet of the product volume section 58.

[0057] Each pump system 50 further includes a return element 54, in the case of a spring, which returns the diaphragm 52 to a stationary position corresponding to a position where the product volume section 58 has an intermediate volume.

[0058] The receiving volume section 62 fluidly connects the driving volume section 60 to the hole 30.

[0059] The receiving volume section 62 extends perpendicularly to the rod 22 in this case.

[0060] The return element 54 is positioned in the receiving volume section 62.

[0061] Furthermore, the pump 10 here includes a pump body 61.

[0062] The pump body 61 defines the receiving volume section 62 in this case.

[0063] When the motor piston 14 is in the first position, the central portion 32 extends toward the pump system of the pump called the first pump system, taking into consideration the receiving volume portion 62 of the pump system in particular.

[0064] When the motor piston 14 is in the first position, the side portion 34 extends toward the second pump system.

[0065] When the motor piston 14 is in the second position, the side portion 34 extends facing the first pump system.

[0066] When the motor piston 14 is in the second position, the central portion 32 extends toward the second pump system.

[0067] Therefore, when the motor piston 14 is displaced between the first and second positions, the hydraulic piston 22 moves in translation, and the entire fluid volume section communicating with the drive volume section 60 of each pump system changes.

[0068] The hydraulic piston 22 drives the pump 10 via the hydraulic system.

[0069] The hydraulic system here extends between the hydraulic piston 22 and the diaphragm or each of the diaphragms 52.

[0070] When the hydraulic piston 22 is displaced, it then displaces the diaphragm 52 in a corresponding manner.

[0071] As a result, the movement of the hydraulic piston 22 drives the operation of the pump, and in this case, the alternating displacement of each diaphragm.

[0072] The entire hydraulic system is filled with oil here.

[0073] The hydraulic system here comprises a hole 30, a receiving volume section 62, and a driving volume section 60.

[0074] For example, oil is supplied through holes at the same number of points as the pump system. Each point is in fluid communication with the corresponding receiving volume section 62.

[0075] The hydraulic system here includes at least one, and in particular two, conduit sections within the pump.

[0076] In particular, the hydraulic system includes a conduit section for each pump system.

[0077] The above-mentioned conduit section or each conduit section extends particularly between the rod 22 of the piston 14 and the diaphragm 52 of the pump 10 or one of them.

[0078] Each conduit section is equipped with a corresponding receiving volume section 62 for the pump system.

[0079] The pump assembly 10 includes at least one, in this case two, air passages 64, 66, which are arranged to allow heat exchange between the hydraulic system and at least one air passage 64, 66.

[0080] For example, the air passage is defined in the main body, in this case the pump body 61, and further defines the hydraulic system, in this case the conduit section.

[0081] Alternatively, at least one air passage is formed in a component surrounding the pump body, the component extending relative to the pump body.

[0082] For example, the pump body is made of metal, particularly aluminum.

[0083] If applicable, for example, the component defining at least one air passage may also be formed from a metal, particularly aluminum.

[0084] At least one air passage 64, 66 can be supplied with air by an air source 68.

[0085] The air source 68 here refers to a compressed air source, specifically compressed air from a compressor.

[0086] This makes it possible to control the air supplied to the air passage.

[0087] For example, a compressor can compress the surrounding air.

[0088] At least one air passage 64,66 is fluidly connected to the motor's air inlet on the opposite side of the air source 68.

[0089] At least one air passage 64, 66 is directly defined in the pump body.

[0090] Each of the above-mentioned air passages or each of the air passages 64, 66 is equipped with an air passage ring 70, 72 that extends around each conduit section or one of them, particularly around the corresponding receiving volume section 62, and especially covers the entire circumference.

[0091] The above rings or each of the rings 70, 72 extend around the central axes X, X'.

[0092] The radial distance between the above ring or each of the rings 70, 72 and the conduit section, in this case the receiving volume section 62, is strictly greater than 0.1 mm.

[0093] The radius distance is selected to resist the pressure acting on the oil, for example, at the maximum hydraulic pressure in the hydraulic system, for example, 240 bar (24 MPa) in this case.

[0094] The radial distance is selected to allow heat exchange between the rings or each of the rings 70, 72 and the conduit.

[0095] In particular, the inner surface of the ring cools the conduit section, and the outer surface also cools the assembly, especially the lower part of the pump.

[0096] The above rings or each of the rings 70, 72 have translational symmetry along the central axes X, X'.

[0097] The above ring or each of the rings 70, 72 has an inner wall 74 and an outer wall 76, and air circulates between the inner wall and the outer wall.

[0098] The thickness of each ring, in other words, the distance between the inner wall 74 and the outer wall 76, is selected in particular to avoid pressure loss to the inlets 78, 80 described below.

[0099] For example, the interior and exterior walls are corrugated in this case.

[0100] Here, the inner and outer walls are corrugated, with grooves parallel to the central axes X and X'.

[0101] Alternatively, the inner and outer walls are corrugated, with grooves perpendicular to the central axes X and X'.

[0102] For example, a groove is a screw.

[0103] As a result, the above ring or each of the rings 70, 72 defines an annular space of the waveform.

[0104] This increases the contact surface, thereby promoting heat exchange between the air in the air passages and the hydraulic fluid in each conduit, and thus the hydraulic system.

[0105] This also causes turbulence, which facilitates heat exchange.

[0106] Alternatively, only the interior or exterior walls may be corrugated.

[0107] Alternatively, the inner and outer walls are not corrugated, and the rings or each of the rings 70, 72 define a conventional annular space.

[0108] At that time, for example, the inner wall and the outer wall have fins.

[0109] Fins facilitate heat exchange.

[0110] The above ring or each of the rings 70, 72 has inlets 78, 80 and outlets 82, 84.

[0111] For example, in each ring 70, 72, the inlets 78, 80 and outlets 82, 84 are oriented directly opposite each other with respect to the central axis.

[0112] Alternatively, for example, the inlets 78, 80 and outlets 82, 84 may form angles ranging from 90° to 180°.

[0113] This allows heat exchange to occur across the entire circumference of the ring.

[0114] Alternatively, the inlets 78 and 80 and the outlets 82 and 84 are not offset in the circumferential direction.

[0115] For example, in each ring 70, 72, the inlets 78, 80 and the outlets 82, 84 are offset along a direction parallel to the central axes X, X' of the ring, for example, by at least two-thirds of the dimensions of the ring along that direction.

[0116] In Figures 1 to 3, each inlet 78, 80 is located on one of planes II, III, while the corresponding outlets 82, 84 are located on the other of planes III, II.

[0117] This allows heat exchange to occur over most of the ring parallel to the central axis.

[0118] Furthermore, this enables the generation of air vortices in each ring 70, 72 around the receiving volume section 62, facilitating exchange between the receiving volume section 62 and the rings.

[0119] For example, the entrances 78 and 80 of rings 70 and 72 are located on the same plane parallel to the central axis of each ring.

[0120] For example, the exits 80 and 82 of rings 70 and 72 are located on the same plane parallel to the central axis of each ring.

[0121] To facilitate understanding of the connections described with reference to Figures 4 and 5, the feature that inlets 78, 80 and outlets 82, 84 are offset in a direction parallel to the ring's central axes X, X' is not shown, and all inlets and outlets are shown schematically here.

[0122] In the first alternative, as shown in Figure 4, the inlet 78 of the first air passage can be connected to an air source 68 so that the air source 68 supplies air to the first air passage.

[0123] The outlet 82 of the first air passage is fluidly connected to the inlet 80 of the second air passage.

[0124] The outlet 84 of the second air passage is fluidly connected to the air inlet 18 of the motor.

[0125] In the second alternative, as shown in Figure 5, the inlets 78 and 80 of the two air passages can be connected to an air source 68 so that the air source 68 supplies air in parallel to the air passages.

[0126] For example, the air source 68 is connected to the inlets 78 and 80 by a T-shaped component.

[0127] The air passage outlets 82 and 84 are connected to the motor's air inlet 18, for example, by a T-shaped component.

[0128] Next, the method of using the pump assembly is described in general terms.

[0129] The motor is activated, similar to how a pump draws up paint products.

[0130] This causes the hydraulic system, in this case, to heat up the oil.

[0131] At least one air passage is supplied with air, in this case compressed air, by an air source.

[0132] Heat exchange occurs between the air in at least one air passage and the hydraulic system.

[0133] This cools the hydraulic system while increasing the temperature of the air.

[0134] Next, the motor is supplied with air from at least one air passage.

[0135] The air supplied to the motor is heated so as to allow the motor to heat up, thereby preventing frost buildup.

[0136] The air supply pressure to the motor is proportional to the air supply pressure in the air passage, which is equal in this case.

[0137] Next, the method of using the first alternative pump assembly is described in more detail.

[0138] The motor is activated, similar to how a pump draws up paint products.

[0139] This causes the hydraulic system, in this case, to heat up the oil.

[0140] The inlet 78 is supplied with air, in this case compressed air, by the air source 68. The air circulates through the first air passage, specifically through the ring, to the outlet 82.

[0141] Through heat exchange between the first air passage and the hydraulic system, in this case the corresponding conduit section, particularly the receiving volume section 62, the temperature of the air increases while the hydraulic system, particularly the corresponding pump system, is cooled.

[0142] Next, air is supplied to the second air passage through the inlet 80.

[0143] The air circulates through the second air passage, specifically through the ring, to the outlet 84.

[0144] Through heat exchange between the second air passage and the hydraulic system, specifically the corresponding conduit section, and in particular the receiving volume section 62, the temperature of the air increases again, while the hydraulic system, especially the corresponding pump system, is cooled.

[0145] This allows the hydraulic system to be cooled at each pump system.

[0146] Finally, the motor is supplied with air from the second air passage.

[0147] The air supplied to the motor is continuously heated to allow the motor to heat up, thereby preventing frost formation.

[0148] Next, a method using a second alternative pump assembly is described in more detail.

[0149] The motor is activated, similar to how a pump draws up paint products.

[0150] This causes the hydraulic system, in this case, to heat up the oil.

[0151] Inlets 78 and 80 are supplied with air, in this case compressed air, by an air source 68. The air circulates in each air passage, and in particular in this case in each ring, in parallel to the corresponding outlets 82 and 84.

[0152] Heat exchange between the corresponding air passage and the hydraulic system increases the temperature of the air while cooling the hydraulic system.

[0153] This allows the hydraulic system to be cooled in parallel at each pump system.

[0154] The motor is supplied with air through an air passage.

[0155] The air supplied to the motor is heated by either the first or second air passage so as to allow the motor to be heated, thereby preventing frost formation.

[0156] Therefore, the pump assembly according to the present invention enables both cooling of the hydraulic system and heating of the motor.

[0157] Furthermore, in this invention, cooling depends on the air supply pressure of the motor, which is directly related to the heating of the oil in the hydraulic system. Therefore, cooling is adjusted according to the possibility of oil heating.

[0158] For example, if a pump is supplied with a low air pressure, say 1 bar (0.1 MPa), and operates at a low flow rate, say 20 cycles per minute, the oil will not be compressed much because the compression is low and occurs at intervals. However, this also means that the air passage is supplied with low air pressure. Therefore, the amount of cooling will be reduced.

[0159] In contrast, if the pump is supplied with a high air pressure, for example 5 bar (0.5 MPa), and operates at a high flow rate, for example 150 cycles per minute, then the oil is compressed more, and the intervals between cycles are shorter. Then the oil is heated more rapidly and rises to a higher temperature. However, the air passage is also supplied with high air pressure, resulting in a greater amount of cooling, and high-pressure, high-speed heat exchange becomes more important.

[0160] As a result, in the pump according to the present invention, the cooling is adapted to the use of the pump.

[0161] Similarly, at low air pressure and low flow rates, the motor is, by default, less at risk of frost formation than at high air pressure and high flow rates. However, in this invention, heat exchange is more important at high air pressure and high flow rates, so the air injected into the motor at the air inlet 18 becomes hotter at high air pressure and high flow rates, contributing more significantly to motor heating and thus preventing frost formation on the motor at high air pressure and high flow rates.

[0162] Therefore, the cooling of the hydraulic system and the heating of the motor are adapted to the use of the pump.

Claims

1. A pump assembly (10) comprising a motor (12) and a hydraulic device (16), particularly for paint fluids, wherein the motor (12) comprises an air inlet (18), the hydraulic device (16) comprises at least one pump system (50), and the motor (12) is capable of driving the at least one pump system (50) by the hydraulic device. The pump assembly (10) comprises at least one air passage (64, 66) arranged to enable heat exchange between the hydraulic system and at least one air passage (64, 66), wherein the at least one air passage (64, 66) can be supplied with air by an air source (68), and the at least one air passage (64, 66) is fluidly connected to the air inlet (18) of the motor (12) on the opposite side of the air source (68).

2. The pump assembly according to claim 1, wherein the air source (68) is a compressed air source, in particular compressed air from a compressor.

3. The pump assembly according to claim 1 or 2, wherein the pump assembly (10) is a diaphragm pump, and the hydraulic system extends between the piston (22) of the hydraulic system (16) and the diaphragm or each diaphragm (52), and the hydraulic system is preferably filled with oil.

4. The pump assembly according to claim 1 or 2, comprising a pump body (61), wherein the at least one air passage (64, 66) is directly defined in the pump body (61).

5. The pump assembly according to claim 1 or 2, wherein the hydraulic system comprises, for example, at least one conduit filled with oil, the conduit extending particularly between the piston (22) of the hydraulic system (16) and at least one diaphragm (52) of the pump (16).

6. The pump assembly according to claim 5, wherein the at least one air passage (64, 66) comprises an air passage ring (70, 72) extending around the conduit or each conduit.

7. The pump assembly according to claim 6, wherein the ring or each ring (70, 72) has an inner wall (74) and an outer wall (76), the air circulates between the inner wall (74) and the outer wall (76), and the inner wall (74) and / or the outer wall (76) are corrugated.

8. The pump assembly according to claim 6, wherein the ring or each ring (70, 72) has an inlet (78, 80) and an outlet (82, 84), and the inlets (78, 80) and outlets (82, 84) of the ring or each ring (70, 72) are opposite to each other.

9. The pump assembly according to claim 6, wherein the ring or each ring (70, 72) comprises an inlet (78, 80) and an outlet (82, 84), and the inlet (78, 80) and the outlet (82, 84) of the ring or each ring (70, 72) are offset in a direction parallel to the central axis (X, X') of the ring (70, 72).

10. The pump assembly according to claim 1 or 2, comprising two air passages, each having an inlet (78, 80) and an outlet (82, 84), wherein the inlet (78) of the first air passage can be fluidly connected to the air source (68) so that the air source (68) supplies air to the first air passage, the outlet (82) of the first air passage is connected to the inlet (80) of the second air passage, and the outlet (84) of the second air passage is connected to the air inlet (18) of the motor (12).

11. The pump assembly according to claim 1 or 2, comprising two air passages, each having an inlet (78, 80) and an outlet (82, 84), wherein the inlets (78, 80) of the two air passages are configured to be fluidly connected to the air source (68) so that the air source (68) supplies air to the air passages, and the outlets (82, 84) of the air passages are connected to the air inlet (18) of the motor (12).

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