High-pressure preload pump and fluid discharge device

Abstract

To provide a pump that delivers fluid at a higher pressure than conventional pumps. [Solution] During operation, the outlet valve element (39) slides airtight within the pump chamber (5), and the inlet valve element (10) slides within the sleeve (9) of the pump body (3) after the inlet valve (11) closes. The sleeve (9) has a smaller diameter than the pump chamber (5), and the inlet valve element (10) is pushed down by the action of pressure applied to the incompressible fluid, compressing the spring (20). At the end of operation, the outlet valve (12) cooperates airtightly with the passage means (40) to open, allowing the fluid in the pump chamber to be discharged. After discharging the fluid, the spring (20) returns the piston (1) to its rest position.

Description

[Technical field]

[0001] The present invention relates to a fluid delivery device including a spray nozzle having a plurality of delivery orifices and a pump for delivering a metered amount of fluid, and in particular to a pre-pressure pump for delivering fluid at a high pressure of at least 15 bar, and a method for assembling the same. [Background technology]

[0002] Fluid discharge devices with discharge nozzles having multiple discharge orifices or outlets are well known from US Pat. Nos. 5,993,333 and 5,143,623. In these documents, the diameter of the outlets is generally 8-20 μm. In US Pat. No. 5,993,333, the nozzle is attached to a pre-pressurized pump that supplies the nozzle with fluid at a pressure of less than 7 bar. In US Pat. No. 5,993,333, the nozzle is attached to either a pump with a pressure of 2-7 bar or a pressurized valve operated with a propellant gas pressure of 6-13 bar. For some nozzles, especially when the diameter of the outlets is less than 5 μm, these pressures may not be sufficient to ensure optimal operation of the device. Furthermore, it may be desirable to use a pre-pressurized pump to avoid propellant gas from the valve, which may be harmful to the user and / or the environment. US Pat. Nos. 5,993,333, 5,143 and 5,152,162 describe other examples of nozzles with microholes.

[0003] Patent documents 6 to 9 disclose pumps that deliver fluid independently of the speed and / or strength of user actuation. During actuation of the pump, a spring is compressed by the pressure generated inside the pump chamber, and the spring is released at the end of actuation after the outlet valve is opened. As a result, the fluid stored in the pump chamber is delivered by the spring independently of the speed of user actuation. Typically, these pumps deliver a pressure of about 6 to 7 bar. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] European Patent Application Publication No. EP1878507 [Patent Document 2] International Publication No. WO2018 / 100321 [Patent Document 3] European Patent Application Publication No. EP1698399 [Patent Document 4] International Publication No. WO2015 / 194962 [Patent Document 5] International Publication No. WO2018 / 219798 [Patent Document 6] International Publication No. WO2014 / 125216 [Patent Document 7] International Publication No. WO0102100 [Patent Document 8] International Publication No. WO8704373 [Patent Document 9] European Patent Application Publication No. EP0265270 Summary of the Invention [Problem to be solved by the invention]

[0005] The object of the present invention is to provide a device and a pump which do not have the above mentioned drawbacks.

[0006] In particular, it is an object of the present invention to provide a fluid dispensing device in which a manually operated pre-load pump for high pressure delivery can be attached to a discharge nozzle provided with several discharge orifices.

[0007] SUMMARY OF THE PRESENT EMBODIMENT It is an object of the present invention to provide a pump which delivers fluid at greater pressure than conventional pumps.

[0008] Another object of the present invention is to provide a pump which is simple and easy to manufacture and assemble, and reliable in its use.

[0009] Another object of the present invention is to provide a pump that ensures complete and reproducible dosing of the contents of the pump chamber with every actuation, regardless of the speed of user actuation.

[0010] Another object of the present invention is to provide a method of assembling a pump which improves the reliability of the pump during storage and use while improving the integrity of the parts, especially those exposed to high pressures during operation. [Means for solving the problem]

[0011] The present invention therefore relates to a pump for discharging a fluid, comprising a piston fixed to an operating rod and sliding in a pump body having a pump chamber defined between an inlet valve and an outlet valve, said outlet valve having an outlet valve part, said outlet valve part sliding in a gas-tight manner in the pump chamber during operation, said pump chamber having passage means, and at the end of the operation of the pump the outlet valve part cooperates non-gas-tightly with the passage means to open the outlet valve and to discharge the fluid stored in the pump chamber, said inlet valve having an inlet valve part, said inlet valve part sliding in a gas-tight manner in the pump chamber during operation, said pump chamber having passage means, after closure of the inlet part, the spring slides in a sleeve of the pump body, said sleeve being reduced in diameter and having a spring seat firstly on the inlet part and secondly on the bottom of the sleeve, said spring further expelling the fluid and returning the piston to its rest position, said spring having a diameter less than 4.2 mm, advantageously less than 4 mm, preferably less than 3.9 mm, said spring force F being at least 20 N, advantageously at least 25 N, so that said pump expels fluid at a pressure P of at least 15 bar, advantageously at least 20 bar.

[0012] Advantageously, a sleeve is inserted into the pump body to reinforce the side walls of the pump chamber.

[0013] Advantageously, said sleeve has a shoulder defining the passage means of said outlet valve.

[0014] Advantageously, the pump body and the sleeve are seal welded together, preferably at their centrifugal flanges, for example ultrasonically.

[0015] Advantageously, the outlet valve component is fixed within the piston.

[0016] Advantageously, the sleeve of the pump body, inside which the inlet valve part slides, has external reinforcing ridges.

[0017] The present invention also relates to a fluid delivery device including a pump as described above. Effect of the Invention

[0018] These and other features and advantages of the invention will become more apparent from the following detailed description, given by way of non-limiting example, and with reference to the accompanying drawings, in which: [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a schematic cross-sectional view of a pump according to the prior art in a rest position. [Diagram 2] FIG. 2 is a cross-sectional view of the pump of FIG. 1 during assembly of the upper piston. [Diagram 3] FIG. 3 is a schematic cross-sectional view of a fluid ejection device in accordance with one advantageous embodiment. [Figure 4] FIG. 4 is an enlarged detailed cross-sectional view of a portion of the pump shown in FIG. [Diagram 5] FIG. 5 is an enlarged, detailed perspective view of another portion of the pump shown in FIG. [Figure 6] FIG. 6 shows a schematic cross-sectional view of a pump according to a first advantageous embodiment in a rest position. [Figure 7] FIG. 7 shows a schematic cross-sectional view of a pump according to a first advantageous embodiment at the start of a working stroke. [Figure 8] FIG. 8 shows a schematic cross-sectional view of a pump according to a first advantageous embodiment during a working stroke. [Figure 9] FIG. 7 shows a schematic cross-sectional view of a pump according to a first advantageous embodiment at the end of its working stroke. [Figure 10] FIG. 10 is a cross-sectional view of a pump according to an advantageous variant of the invention in the rest position. [Figure 11] FIG. 11 is a cross-sectional view of a pump according to an advantageous variant of the invention shown at the end of its working stroke. [Figure 12] FIG. 12 is a schematic cross-sectional view of a portion of the pump of FIG. 6 during assembly of the upper piston. [Figure 13] FIG. 13 is a schematic cross-sectional view of a portion of the pump of FIG. 6 after the upper piston has been assembled. [Figure 14] FIG. 14 is a schematic cross-sectional view of a portion of the pump of FIG. 6 during assembly of the bottom piston. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Different aspects of the present invention will be described with reference to several embodiments and modifications, although it goes without saying that the present invention is not limited to the embodiments shown in the drawings.

[0021] 1 and 2 show a prior art pump described in US Pat. No. 5,399,633.

[0022] 1 and 2, this prior art pump includes a pump body 3. When a user presses an actuation rod 2 fixed to a piston 1, the pump is actuated and the piston 1 slides within the pump body 3. The piston 1 slides within a pump chamber 5 defined by an inlet valve 11 and an outlet valve 12 within the pump body 3. A fixing ring 4 can be used to fix the pump to a tank, for example, by crimping, screwing or snapping.

[0023] The inlet valve 11 is open in the rest position of the pump and consists of an inlet valve part 10 as seen in Fig. 1. The inlet valve part 10 moves inside the pump body 3 during the operation of the pump and cooperates with a part of the pump body 3 to close the inlet valve in the start position of the pump. The inlet valve part 10 is a hollow cylinder with a bottom at one end, and the edge at the open end of the hollow cylinder cooperates airtightly with the cylinder 9 of the pump body 3 to close the inlet valve 11 from the start of the operation of the pump. A spring 20 presses against the bottom wall of the inlet valve part 10 on the one hand and against a part of the pump body 3 on the other hand.

[0024] The outlet valve 12 comprises an outlet valve part 39, advantageously formed by the lower lip of the piston 1. The outlet valve 12 is opened during operation of the pump only at the end of the operation of the pump to allow the discharge of fluid from within the pump chamber. The opening of the outlet valve 12 is achieved by passage means formed in a radially inner shoulder 40 of the pump body. The passage means 40 are provided for closing at least one flow path when the outlet valve part 39 reaches the passage means 40 at the end of the operating stroke of the pump after having cooperated in gas-tight relation with the pump body 3 over the entire operating stroke of the pump.

[0025] The fluid in the pump chamber 5 is discharged regardless of the speed of the user's actuation. For this purpose, the inlet valve 10 cooperates with a spring 20 which is compressed during the operation of the pump by the movement of the inlet valve part 10 under pressure in the pump chamber. At the end of the working stroke of the pump, at the moment when the outlet valve 12 is opened, the spring 20 discharges the fluid in the pump chamber when it is released from compression. Advantageously, the spring 20 of the inlet valve 11 also acts as a return spring for the pump, returning the piston 1 to its rest position after the fluid has been discharged.

[0026] The pump of figures 1 and 2 therefore comprises two pistons: on the one hand, a part of the piston 1 defines the outlet valve, and on the other hand, an inlet valve part 10 defines the inlet valve and, during operation, acts as a piston against the outer surface of the cylinder 9 of the pump body 3.

[0027] In figure 2 it can be seen that during assembly, the two pistons are assembled into the body from above. The lower lip 39 of the piston 1, which constitutes the outlet valve part and abuts against the inlet of the pump body 3, may therefore be weakened. If the lip 39 is directed axially downwards in figure 2, it will necessarily be airtight, since its radially outer end will be in contact with the pump body during assembly. Depending on the force with which this part is assembled into the pump body, its integrity may change, which may result in a loss of airtightness, especially under high pressure.

[0028] Similarly, the inlet valve part 10 is also assembled around the sleeve 9 with its sealing lip abutting the upper edge of said sleeve. Again, if the sealing surface of this lip is damaged, the tightness of the inlet valve part may be altered.

[0029] The prior art pump shown in Figures 1 and 2 typically exerts a pressure of about 7 bar. This pressure P is equal to the spring force F divided by the area S over which the spring force F acts, according to the formula P=F / S. In the example of Figures 1 and 2, the spring 20 typically has a force F of 13 N and an area S which corresponds to the outer diameter of the sleeve 9 (typically 4.9 mm), around which the inlet valve part 10 moves during operation, typically 18.8 mm. 2 Thus, the pressure P is about 7 bar. If the spring 20 is replaced, for example, by a spring with a force F of 25 N, the pressure P can reach about 13 bar. However, it is not practical to consider this for several reasons. On the one hand, due to its dimensions, a spring force F of 25 N in the pump shown in FIG. 1 would be difficult to activate, especially for elderly or frail users. On the other hand, such a high pressure would be too great for the two pistons to support, which could lead to the sealing lip being damaged during assembly of the pump (see above). The risk of leakage or malfunction would become too high, and the reliability of the correct delivery of fluid per activation would decrease.

[0030] In particular, the invention provides a precompression pump adapted to apply a pressure of at least 15 bar, advantageously at least 20 bar.

[0031] For this reason, the structure and operation of the prior art pump of Figures 1 and 2 are modified as described below.In Figures 3 to 14, the same or similar parts are designated by the same reference numerals.

[0032] Like the pump of figures 1 and 2, the pump according to the invention comprises a pump body 3. In the pump body 3, the user operates the pump by pressing an actuating rod 2, thereby sliding a piston 1 fixed to the actuating rod 2. The piston 1 slides in a pump chamber 5. The pump chamber 5 is defined in the pump body 3 between an inlet valve 11 and an outlet valve 12. A fixing ring 4 may fix the tank to the pump, for example by crimping, screwing or snap-fitting.

[0033] A sleeve 50 is inserted into the pump body 3 to reinforce the side walls of the pump chamber 5. The sleeve 50 may, for example, be partially fixed to the fixing ring 4. The sleeve 50 may thus form a double wall in the pump chamber 5, preventing deformation of the inner walls of the pump chamber 5 due to the high pressure exerted by the pump during operation. The sleeve 50 has a radial shoulder, which defines the outlet valve 40. Advantageously, as shown in FIG. 4, a sealing weld 55 may be provided, for example ultrasonically, to prevent leakage between the sleeve 50 and the pump body 3. The sealing weld 55 is preferably provided between the respective radial flanges of the pump body 3 and the fixing ring 4 incorporating the sleeve 50.

[0034] Similarly, the sleeve 9 cooperates with the inlet valve part 10 and extends axially downwards in the pump body 3 and houses the inlet valve part 10 and a spring 20. The inlet valve part 10 is solid and has peripheral sealing lips which extend radially. In the rest position, as shown in particular in FIG. 6, these sealing lips do not cooperate in an airtight manner with the sleeve 9 and the inlet valve 11 is open. In operation, by compressing the spring 20, the inlet valve part 10 slides axially in the sleeve 9. This sliding is performed in an airtight manner, the sealing lips of the inlet valve part 10 co-operating in an airtight manner with the sleeve 9.

[0035] The sleeve 9 is tapered relative to the pump body 3. Advantageously, as shown in particular in figures 5 and 7 to 9, the sleeve 9 is provided with an external reinforcing ridge 90. In this way, the sleeve 9 can be made radially smaller, typically with an inner diameter smaller than the outer diameter of the sleeve 9 of the pump of figure 1. Thus, for example, the diameter of the sleeve 9 of the pump of figure 6 is less than 4.2 mm, advantageously less than 4 mm and preferably less than 3.9 mm.

[0036] The piston 1 and the outlet valve part 39 may be formed in one piece, but preferably, as shown in Figures 3 and 6 to 14, the outlet valve part 39 is formed by a separate part which is fixed to the piston 1. This fixing can be by means of a force fit, a snap fit, a screwing or any other suitable fixing method. The sealing lips of the piston 1 and the outlet valve part 39 face in the same direction, which in the position of Figure 6 are pointing downwards.

[0037] One of the features of the pump according to the invention is that the piston 1 and the outlet valve part 39 are assembled in the sleeve 50. In contrast to the pump of figures 1 and 2, this assembly is carried out from the bottom, as shown in figures 12 and 13. Such assembly therefore does not weaken the sealing lip, which faces in the opposite direction to the assembly direction. In this way, the sealing lip is not plastically deformed by the frontal contact of its radially outer surface with the sleeve 50 of the pump chamber 5, but, in contrast, there is no risk of the sealing lip being subjected to sudden forces on the sealing surface as a result of a gradual radially inward deformation of the sealing lip, which would result in a change in the sealing performance.

[0038] The sealing lips of the inlet valve part 10 face in the opposite direction to the sealing lips of the piston 1 and the outlet valve part 39. As shown in Figure 14, the inlet valve part 10 is assembled directly onto the sleeve 9 of the pump body. In this way, none of the sealing lips are damaged during assembly.

[0039] The pump according to the invention therefore substantially improves the sealing performance of the different sealing parts: the piston 1 , the outlet valve part 39 and the inlet valve part 10 .

[0040] It is therefore possible to use a spring with a greater force, typically at least 20N, advantageously 25N.

[0041] The inner diameter of the sleeve 9 is 3.9 mm, i.e. the surface area is 12 mm 2 With a 20N spring, the pressure P reaches about 16.5 bar. With a 25N spring, the pressure rises to about 21 bar.

[0042] Thus, according to the invention, a standard precompression pump can be provided, but capable of discharging fluid at a pressure of at least 15 bar, advantageously around 20 bar, which is higher than conventional standard pumps and higher than valves operated by propellant gas.

[0043] The spring has a mass of 25N and a surface area S of 12mm 2 The actuation force of such a pump is less than 60N and can advantageously tolerate up to about 50N.

[0044] The present invention also provides an advantageous assembly method, which comprises the steps of: (a) A piston 1 is fixed to an actuating rod 2. (b) A pump chamber 5 is provided in the pump body 3; (c) providing a sleeve 50, advantageously fixed to the fixing ring 4; (d) providing an outlet valve element 39 which slides gas tight within the pump chamber 5 during operation; (e) a sleeve 9 of the pump body 3, and an inlet valve member 10 sliding within the reduced diameter sleeve 9; (f) Provide a spring 20.

[0045] The method further comprises the steps of: (g) Fixing the outlet valve part 39 in the piston 1; (h) inserting the piston 1 and outlet valve part 39 into the sleeve 50 from the bottom in the direction of fluid flow during discharge; (i) inserting the spring 20 and the inlet valve part 10 into the reduced-diameter sleeve 9 from above, in the direction opposite to the direction of fluid flow during discharge, so as to compress the spring 20 between the bottom of the sleeve 9 and the inlet valve part 10; (j) The sleeve 50 is inserted into the pump body 3 from above in the opposite direction to the flow direction of the fluid when discharged.

[0046] It should be noted that the step of inserting the spring 20 and the inlet valve part 10 into the reduced diameter sleeve 9 may be performed prior to the step of inserting the piston 1 and the outlet valve part 39 into the sleeve 50 .

[0047] The operation of the pump is shown in Figures 6 to 9.

[0048] In the feed position, as shown in FIG. 6, the inlet valve 11 is open and the outlet valve 12 is closed.

[0049] At the start of operation, the inlet valve 11 is closed while the outlet valve 12 remains closed due to the airtight cooperation of the lips of the inner cylindrical surfaces of the inlet valve part 10 and the sleeve 9, as shown in Figure 7. As the inlet valve part 10 slides within the sleeve 9, the spring 20 is compressed. Since the sleeve 9 has a smaller diameter than the sleeve 50 disposed within the pump body 3 and the fluid contained within the pump chamber 5 is incompressible, the spring 20 can be compressed relatively easily despite the increased force of the spring 20.

[0050] Towards the end of the actuation, the outlet valve component 39 approaches the outlet valve shoulder 40, opening the outlet valve, as shown in FIG.

[0051] 9 shows the actuated position, in which, when the outlet valve is opened, the contents of the pump chamber 5 are expelled under the effect of the spring 20 no longer being compressed, so that the fluid is expelled at a pressure of at least 15 bar, advantageously at least 20 bar.

[0052] Figures 10 and 11 show a variant in which the user's actuation force is assisted and reduced by providing a second spring 80. In this variant, the second spring 80 is advantageously arranged around the piston 1 and biases the piston towards its actuated position. The second spring 80 therefore acts against the spring 20, so its force must be less than that of the spring 20.

[0053] When using such a second spring 80, it is conceivable to use a spring 20 with a force F of, for example, greater than 30 N, advantageously greater than 35 N, for example 38 N. This spring 20 has a surface area S of 12 mm 2 In this case, it is possible to reach a pressure P of more than 25 bar, advantageously more than 30 bar, for example 32 bar.

[0054] Advantageously, the piston 1 can be fixed to an outer sleeve 2' assembled around the actuating rod 2, which itself is fixed to the outlet valve part 39. This implementation can also be applied to the variants of figures 6 to 9.

[0055] The present invention also relates to a fluid product dispensing apparatus comprising a pump as described above fitted with a spray nozzle having a plurality of discharge orifices.

[0056] For example, when using the microhole nozzle described in Patent Document 2, high pressure fluids of typically more than 15 bar are required depending on the nozzle design, especially when the diameter of the microholes is less than 5 μm or even less than 2 μm. According to the present invention, a pressure of at least 15 bar, advantageously at least 20 bar, can be ensured without the use of a propellant gas.

[0057] As shown in FIG. 3, the device comprises a body 101 that houses a tank 100 on which a pump as described above is mounted using a fixing ring 4.

[0058] The tank 100 preferably does not have an air inlet. Advantageously, a deformable pouch 105 is fixed inside said tank 100, said pouch containing a fluid and deforming as the fluid is dispensed. Preferably, the filling of the pouch can be carried out under vacuum. This implementation allows almost all of the fluid contained in the pouch to be dispensed, allows the device to be operated in any direction and avoids any risk of contamination of the fluid contained in the pouch. In a variation of the pouch, a driven piston may be used in the tank 100.

[0059] In some cases, devices operating by suction air can also be used, in which case a filter is advantageously provided for filtering the air.

[0060] The micro-hole nozzle 200, the operation of which will not be described in more detail below, may be of any known type, for example as described in US Pat. Nos. 5,999,103, 5,103,141, 5,104,152, and is disposed in a discharge tip 110 fixed to the body 101. The discharge tip 110 may be, for example, a mouthpiece. Typically, the fluid discharged by the pump strikes a plate provided with a number of micro-holes, generating a spray of the fluid.

[0061] The diameter of the micro-holes in the nozzle 200 is less than 5 μm, preferably less than 2 μm.

[0062] Advantageously, a filter 150 is interposed between the pump outlet and the nozzle 200. This filter is used to filter out impurities that may be transported by the fluid as it passes through the different plastic parts. In fact, there is still a risk of particles being generated during the manufacturing and assembly process, which may block the micro-holes of the nozzle.

[0063] Advantageously, the body 101 is provided with a side actuation arm 160 to allow actuation of the pump by side actuation.

[0064] Of course, the invention is not limited to the embodiments shown in the drawings, its scope being defined on the contrary by the appended claims. [Industrial Applicability]

[0065] The high pressure pre-load pump according to the present disclosure is useful as a pre-load pump discharging fluid at a high pressure of at least 15 bar. [Explanation of symbols]

[0066] 1...Piston 2...Operating rod 3. Pump body 4…Fixing ring 5…Pump chamber

Claims

1. 1. A high pressure pump for discharging a fluid, comprising a piston (1) fixed to an actuating rod (2) and sliding within a pump body (3) having a pump chamber (5) defined between an inlet valve (11) and an outlet valve (12), the high pressure pump comprising: the outlet valve (12) comprises an outlet valve part (39) that slides airtightly within the pump chamber (5) during the operation of the actuation rod (2) in a direction from downstream to upstream in a fluid discharge direction; said pump chamber (5) is provided with passage means, and at the end of the operation of said high pressure preload pump, said outlet valve part (39) cooperates non-tightly with said passage means (40) to open said outlet valve (12) and allow the discharge of the fluid contained in said pump chamber; The inlet valve (11) comprises an inlet valve part (10), which slides in a sleeve (9) of the pump body (3) after the inlet valve (11) is closed; the sleeve (9) is of smaller diameter than the pump chamber (5) and accommodates a spring (20) which firstly supports the inlet valve part (10) and secondly supports the bottom of the sleeve (9); In addition to discharging the fluid, the spring (20) applies a force to the piston (1) in a direction from the upstream side to the downstream side in the fluid discharge direction to return the piston (1) to its rest position; The sleeve (9) has an inner diameter of less than 4.2 mm; the spring (20) has a force of at least 20N, such that the high pressure pump delivers the fluid at a pressure (P) of at least 15 bar; A second sleeve (50) is inserted into the pump body (3) to reinforce the side wall of the pump chamber (5); the second sleeve (50) has a shoulder defining the passage means (40) of the outlet valve (12); The second sleeve (50) has a main body portion on the downstream side in the fluid discharge direction and a bottom portion on the upstream side in the fluid discharge direction, with the shoulder portion sandwiched therebetween, and the inner diameter of the bottom portion is larger than the inner diameter of the main body portion, The outlet valve part (39) is provided with a sealing lip, and when the sealing lip is located on the main body part during operation within the second sleeve (50), the sealing lip performs the airtight sliding, and when the sealing lip reaches the bottom part having a diameter larger than that of the main body part at the end of operation, the airtightness by the sealing lip is released, thereby transitioning to the non-airtight cooperation, and opening the outlet valve (12); Furthermore, a second spring (80) is fitted to a portion of the second sleeve (50) that is inserted into the main body portion and is located downstream of the operating rod (2) in the fluid discharge direction, The second spring (80) has a smaller force than the spring (20) and applies a force to the operating rod (2) in a direction from the downstream side to the upstream side in the fluid discharge direction. A high pressure preload pump.

2. An ultrasonically sealed weld (55) is provided between the pump body (3) and the second sleeve (50).

2. The high pressure preload pump according to claim 1.

3. The outlet valve part (39) is fixed to the piston (1).

3. The high pressure preload pump according to claim 1 or 2.

4. The sleeve (9) of the pump body (3) in which the inlet valve part (10) slides includes an external reinforcing ridge (90) 4. The high pressure preload pump according to claim 1, wherein the pressure is increased by a large amount.

5. The sleeve (9) has an inner diameter of less than 4 mm 5. The high pressure preload pump according to claim 1,

6. The sleeve (9) has an inner diameter of 3.9 mm.

6. The high pressure preload pump according to claim 5.

7. The spring (20) has a force of at least 25N, so that the high pressure pump delivers the fluid at a pressure (P) of at least 20 bar.

7. The high pressure preload pump according to claim 1,

8. A high pressure preload pump according to any one of claims 1 to 7 is included. A fluid ejection device comprising:

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