CN214242035U

CN214242035U - Current-limiting pump head

Info

Publication number: CN214242035U
Application number: CN202120103259.4U
Authority: CN
Inventors: 熊明阳
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-01-14
Filing date: 2021-01-14
Publication date: 2021-09-21
Anticipated expiration: 2031-01-14

Abstract

The utility model provides a current-limiting pump head relates to the household articles field. The pressure pipe comprises a pump core, a shell, a pressure pipe and an adjusting sleeve, wherein the pump core is arranged in the shell. The inner wall of the shell is provided with a fixed sleeve, the adjusting sleeve extends into the fixed sleeve and is in threaded connection with the fixed sleeve, one end of the pressing pipe penetrates through the adjusting sleeve and is connected with the pump core, and the pressing pipe is used for controlling the pump core to act to discharge liquid. The other end of the pressing pipe extends out of the shell, the pressing pipe is in clearance fit with the adjusting sleeve, and a spray head is arranged at one end of the pressing pipe extending out of the shell. The pump head is typically mounted above the bottle body. When using this pump head, according to user's actual conditions, highly adjusting the adjusting collar, and then restrict the stroke of pressing of shower nozzle to the realization is adjusted the extrusion volume of pump head, in order to satisfy user's user demand.

Description

Current-limiting pump head

Technical Field

The utility model relates to a furniture articles for use field particularly, relates to a current-limiting pump head.

Background

At present, a downward-pressing pump head is mainly applied to bottles of daily chemical products such as hand sanitizer, shampoo and the like, and the principle is that air in a liquid storage cavity is discharged by pressing and utilizing atmospheric pressure. After the air was discharged, pressed the pump head once more, after the pine hand, the spring in the pump head will the reconversion, just can form the vacuum in the stock solution chamber so, produces the negative pressure. At this time, the pressure in the container is kept consistent with the atmospheric pressure, and the pressure in the liquid storage cavity is small, and the pressure in the container is large, so that the atmospheric pressure can press the liquid around the opening of the liquid storage cavity into the liquid storage cavity and discharge the liquid due to the pressure difference.

The pump heads are fixed on the bottle body in a threaded connection mode, and when the head cap of the pump head is manually pressed, liquid in the bottle is sucked by air pressure and is sprayed out through the nozzle on the head cap. Because the liquid pumping amount is set when the pump is delivered from a factory, the extrusion amount of the existing pump head is constant and cannot be adjusted. However, in different situations, different users need to press out the same amount of liquid each time, which requires great attention of the users each time the users press the liquid, and the liquid can be pressed to the bottom by carelessness and excessive force, which causes excessive squeezing and is extremely inconvenient for the users to use the liquid daily.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a current-limiting pump head for improve the unable problem of adjusting the volume of extruding of pressing the pump head among the prior art.

The embodiment of the utility model is realized like this:

the embodiment of the application provides a current-limiting pump head, and it includes pump core, casing, presses pipe and adjusting collar, and the pump core sets up in the casing. The inner wall of the shell is provided with a fixed sleeve, the adjusting sleeve extends into the fixed sleeve and is in threaded connection with the fixed sleeve, one end of the pressing pipe penetrates through the adjusting sleeve and is connected with the pump core, the pressing pipe is used for controlling the pump core to act to discharge liquid, the other end of the pressing pipe extends out of the shell, the pressing pipe is in clearance fit with the adjusting sleeve, and one end of the pressing pipe extending out of the shell is provided with a spray head.

The utility model discloses an in some embodiments, above-mentioned pump core is including setting gradually feed liquor check valve, spring in the casing and go out the liquid check valve, and the spring is located the feed liquor check valve and goes out between the liquid check valve, and the one end and the casing of spring are connected, and the other end and the play liquid check valve of spring are connected, go out the liquid check valve and press the union coupling.

In some embodiments of the present invention, the housing includes a liquid suction pipe, and the liquid suction pipe is connected to the liquid inlet check valve.

The utility model discloses an in some embodiments, above-mentioned play liquid check valve includes the piston, and the piston separates the casing for interior cavity and outer cavity, has seted up first through-hole on the piston, presses the pipe and can stretch into in the interior cavity along first through-hole, presses the inner wall sliding seal who presses pipe and first through-hole to be connected, presses to have seted up the second through-hole on the pipe, second through-hole and interior cavity intercommunication.

In some embodiments of the present invention, a retaining ring is disposed in the outer chamber, and the retaining ring is disposed on the pressing pipe.

In some embodiments of the present invention, the casing has an air pressure balancing hole, and the air pressure balancing hole is communicated with the outer cavity.

In some embodiments of the present invention, the nozzle is disposed on the nozzle head, and the nozzle communicates with the pressing pipe.

In some embodiments of the present invention, a rotating handle is disposed on an end of the adjusting sleeve extending out of the housing.

In some embodiments of the present invention, the rotation handle is covered with an anti-slip layer.

The utility model discloses an in some embodiments, an pot head of above-mentioned casing is equipped with joint spare, and joint spare includes ring groove, and in the one end of casing can stretch into ring groove, joint spare was connected with fixed cover.

Compared with the prior art, the embodiment of the utility model has following advantage or beneficial effect at least:

the utility model provides a pair of current-limiting pump head, it includes pump core, casing, presses pipe and adjusting collar, and the pump core sets up in the casing. The inner wall of the shell is provided with a fixed sleeve, the adjusting sleeve extends into the fixed sleeve and is in threaded connection with the fixed sleeve, one end of the pressing pipe penetrates through the adjusting sleeve and is connected with the pump core, and the pressing pipe is used for controlling the pump core to act to discharge liquid. The other end of the pressing pipe extends out of the shell, the pressing pipe is in clearance fit with the adjusting sleeve, pressing through the pressing pipe can be achieved, and the gap between the pressing pipe and the adjusting sleeve is favorable for gas flowing, so that the pressing pipe is enabled to recover to a state before pressing as soon as possible. The one end of pressing the pipe and stretching out the casing is provided with the shower nozzle, and the shower nozzle can not stretch into the adjusting collar, and the setting of shower nozzle can prevent to press the pipe too and be absorbed in the adjusting collar because press excessively. In the above implementation, the pump head is usually installed above the bottle body. When using this pump head, according to user's actual conditions, highly adjusting the adjusting collar, and then restrict the stroke of pressing of shower nozzle to the realization is adjusted the extrusion volume of pump head, in order to satisfy user's user demand.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a flow-limiting pump head according to an embodiment of the present invention;

FIG. 2 is an enlarged view of a portion of FIG. 1 at A;

fig. 3 is a partially enlarged view of B in fig. 1.

Icon: 1-a shell; 2-pressing the pipe; 3-adjusting sleeve; 4-fixing the sleeve; 5-liquid inlet one-way valve; 6-a spring; 7-a piston; 8-pipette; 9-a second via; 10-a baffle ring; 11-air pressure balancing holes; 12-a spray head; 13-a nozzle; 14-a turning handle; 15-a clip; 16-an inner chamber; 17-an outer chamber; 18-a first chamber; 19-second chamber.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the embodiments of the present invention, it should be noted that, if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the product of the present invention is used, the description is only for convenience of description of the present invention and simplification, but the indication or suggestion that the device or element to be referred must have a specific position, be constructed and operated in a specific position, and therefore, the present invention should not be construed as being limited thereto. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not require that the components be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the embodiments of the present invention, "a plurality" means at least 2.

In the description of the embodiments of the present invention, it should be further noted that unless explicitly stated or limited otherwise, the terms "disposed," "mounted," "connected," and "connected" should be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

Examples

Referring to fig. 1 and 2, fig. 1 shows a flow-limiting pump head according to an embodiment of the present invention, fig. 2 is a partial enlarged view of a portion a in fig. 1, and fig. 3 is a partial enlarged view of a portion B in fig. 1.

The embodiment provides a current-limiting pump head, which comprises a pump core, a shell 1, a pressing pipe 2 and an adjusting sleeve 3, wherein the pump core is arranged in the shell 1. The inner wall of the shell 1 is provided with a fixed sleeve 4, the adjusting sleeve 3 extends into the fixed sleeve 4 and is in threaded connection with the fixed sleeve 4, one end of the pressing pipe 2 penetrates through the adjusting sleeve 3 and is connected with the pump core, and the pressing pipe 2 is used for controlling the pump core to act to discharge liquid. The other end of the pressing pipe 2 extends out of the shell 1, the pressing pipe 2 is in clearance fit with the adjusting sleeve 3, pressing through the pressing pipe 2 can be achieved, and the gap between the pressing pipe 2 and the adjusting sleeve 3 is favorable for gas flowing, so that the pressing pipe 2 is enabled to recover to a state before pressing as soon as possible. One end that the pressure pipe 2 stretches out the casing 1 is provided with shower nozzle 12, and shower nozzle 12 can not stretch into adjusting collar 3, and the setting of shower nozzle 12 can prevent because press excessively, press pipe 2 too to be absorbed in adjusting collar 3. In the above implementation, the pump head is usually installed above the bottle body. When using this pump head, according to user's actual conditions, adjust the height of adjusting collar 3, and then restrict the stroke of pressing of shower nozzle 12 to the realization is adjusted the extrusion volume of pump head, with the user demand that satisfies the user.

Wherein, the fixed sleeve 4 is fixed on the inner wall of the shell 1 and is contacted with the pump core. Set up fixed cover 4 with above-mentioned mode, when the user need reduce every pump liquid volume of pumping, can upwards adjust this adjusting collar 3, fixed cover 4 can prevent that the pump core from upwards moving along with adjusting collar 3's regulation, and then prevents to press pipe 2 and upwards bounce along with the upwards moving of pump core to avoid losing the regulation effect. When the user need increase every pump and go out the liquid measure, can adjust adjusting collar 3 downwards, fixed cover 4 can prevent that the pump core from moving downwards along with adjusting of adjusting collar 3, and then the action of restriction pump core to avoid the phenomenon that liquid flows out when adjusting this adjusting collar 3.

In some embodiments of this embodiment, the pump core includes liquid inlet check valve 5, spring 6 and the play liquid check valve that sets gradually in casing 1, and spring 6 is located between liquid inlet check valve 5 and the play liquid check valve, and the one end of spring 6 is connected with casing 1, and the other end of spring 6 is connected with a play liquid check valve, goes out the liquid check valve and is connected with pressing pipe 2. Specifically, the liquid inlet one-way valve 5 is close to one end of liquid inlet in the pump core, and the liquid outlet one-way valve is close to one end of liquid outlet in the pump core. The inner chamber 16 may include a first inner chamber 16 and a second inner chamber 16, and each of the first inner chamber 16 and the second inner chamber 16 may be a rectangular chamber. It should be noted that the width of the first chamber 18 is smaller than the width of the second chamber 19. The liquid inlet check valve 5 may be a steel ball, the diameter of the steel ball is equal to the width of the second chamber 19, and when the user presses the pressing pipe 2, the steel ball will move to the connection between the first chamber 18 and the second chamber 19, so that the liquid will not flow into the second chamber 19. When the user releases the pressing tube 2, the steel ball will move towards the direction close to the spring 6, so that the liquid flows into the second chamber 19, and the opening and closing of the liquid inlet check valve 5 can be realized in the above manner.

In the above process, when the user presses the spray head 12, the spring 6 will be in a compressed state, the liquid inlet check valve 5 will be closed, and the liquid outlet check valve will be opened, so that the volume inside the shell 1 is reduced, and the liquid will be discharged from the pressing pipe 2. When the user is loose, spring 6 will the reconversion for press pipe 2 upwards to bounce, make the inside volume increase of casing 1, at this moment, feed liquor check valve 5 will be opened, go out the liquid check valve and will close, under atmospheric pressure, in liquid will get into inner chamber 16, thereby make can be full of liquid in the inner chamber 16, made things convenient for liquid can follow a liquid check valve and discharged.

The spring 6 may be a compression spring. The compression spring is a coil spring that receives a biasing force. The compression spring has certain clearance between the circle, and when receiving pressure, compression spring can contract the deformation, and when pressure disappears, compression spring can resume the shape. Since the compression spring has the above-described characteristics, when the spring 6 is a compression spring, it is possible to realize springback of the spring 6.

The spring 6 may be a return spring. The return spring has a characteristic of being restored to a state without an external force when the external force disappears. When the spring 6 is a return spring, the pressing tube 2 and the pressure limiting head 12 can be restored to the initial positions after the external force disappears.

The compression spring 6 and the return spring 6 selected for the spring 6 are only two options of the embodiment in the present embodiment, and the selection of the spring 6 is not limited.

In some embodiments of the present embodiment, the housing 1 comprises a pipette 8, the pipette 8 is connected to the liquid inlet check valve 5, and the pipette 8 is used for sucking the liquid in the bottle into the housing 1. In particular, when the user releases his hand, the liquid in the bottle can be drawn into the housing 1 by the pipette 8 under atmospheric pressure, thereby achieving that the inner chamber 16 can be in a liquid filled state.

In some embodiments of this embodiment, the liquid outlet check valve includes a piston 7, the piston 7 is disposed in the housing 1, the piston 7 divides the housing 1 into an inner chamber 16 and an outer chamber 17, a first through hole is opened on the piston 7, the pressing pipe 2 can extend into the inner chamber 16 along the first through hole, the pressing pipe 2 is connected with an inner wall of the first through hole in a sliding and sealing manner, specifically, no gap exists between the pressing pipe 2 and the piston 7, the pressing pipe is in a sealing state, and the pressing pipe 2 can slide along the inner wall of the first through hole, so that the pressing pipe 2 is connected with the inner wall of the first through hole in a sliding and sealing manner. A second through hole 9 is formed in the pressing pipe 2, and the second through hole 9 is communicated with the inner cavity 16. The pressing pipe 2 extends into the inner cavity 16 along the first through hole and is connected with the piston 7 in a sliding mode, the spring 6 is connected with the pressing pipe 2 through a connecting plate, the connecting plate enables the end, extending into the inner cavity 16, of the pressing pipe 2 to form a closed structure, the second through hole 9 is formed in the pressing pipe 2, and when a user presses the pressing pipe 2, liquid can flow into the pressing pipe 2 from the inner cavity 16. In the implementation process, no gap exists between the pressing tube 2 and the piston 7, and the pressing tube is in a sealing state, so that liquid cannot leak from the connection part of the pressing tube 2 and the piston 7. Specifically, when the user presses the pressing tube 2, the liquid in the inner chamber 16 flows into the pressing tube 2 through the second through hole 9. When the user looses his hand, the second through hole 9 will be blocked by the inner wall of the first through hole and liquid will flow into the inner chamber 16. Wherein no liquid is present in the outer chamber 17 at all times. Through the mode, the liquid outlet one-way valve can be formed by the piston 7 and the pressing pipe 2, and then the liquid outlet one-way valve is opened and closed through the matching of the piston 7 and the pressing pipe 2, so that the effect of spraying liquid from the pressing pipe 2 is achieved.

In some embodiments of the present embodiment, the blocking ring 10 is disposed in the outer chamber 17, and the blocking ring 10 is sleeved on the pressing pipe 2, so that the pressing pipe 2 can have an effect of limiting the movement of the piston 7. In the implementation process, when the baffle ring 10 is in contact with the piston 7, the piston 7 stops moving, and the pressing pipe 2 moves upwards until the spring 6 returns to the original position, so that the second through hole 9 on the pressing pipe 2 is blocked by the inner wall of the first through hole.

In some embodiments of the present invention, the housing 1 is provided with an air pressure balancing hole 11, the air pressure balancing hole 11 is communicated with the outer chamber 17, and the air pressure balancing hole is used for air circulation between the outer chamber 17 and the inside of the bottle, so as to balance the air in the outer chamber 17. Specifically, when the sprayer 12 is pressed, the volume of the gas in the outer chamber 17 is small, which may cause unsmooth pressing, and the arrangement of the gas balance holes helps the gas in the outer chamber 17 and the bottle to circulate, so that the user can press smoothly.

In some embodiments of the present embodiment, the nozzle 13 is disposed on the nozzle 12, and the nozzle 13 is communicated with the pressing pipe 2. In the above implementation, the interior of the spray head 12 may include a cavity. When the spray head 12 is pressed, the liquid in the pressing tube 2 may first be sprayed into the cavity, and then the liquid may be sprayed from the nozzle 13. The pressing pipe 2 and the spray head 12 are simple in structure and cannot cause liquid blockage.

In some embodiments of the present embodiment, the end of the adjusting sleeve 3 extending out of the housing 1 is sleeved with a rotation handle 14. Specifically, when the user adjusts the adjusting sleeve 3, because the adjusting sleeve 3 is connected with the fixed sleeve 4 through the screw thread, the adjusting sleeve 3 is connected with the fixed sleeve 4 more closely, the adjusting sleeve 3 is directly rotated, and the adjustment of the adjusting sleeve 3 may not be smoothly realized. The arrangement of the rotating handle 14 enables a user to drive the adjusting sleeve 3 to rotate through the rotation of the rotating handle 14, the rotating handle 14 facilitates the use of the user, and the user can adjust the adjusting sleeve 3 conveniently.

In some embodiments of this embodiment, the rotation handle 14 is covered with an anti-slip layer. Specifically, because fixed cover 4 and adjusting collar 3 threaded connection, when the user rotates and rotates handle 14, the phenomenon of skidding can appear, and the setting on skid resistant course can prevent effectively that the user from rotating when rotating handle 14, the phenomenon of skidding appears to the user has made things convenient for the regulation of user to adjusting collar 3.

Optionally, the anti-slip layer comprises vertical stripes. Since the rotating handle 14 needs to be rotated when the user adjusts the adjusting sleeve 3, the vertical stripes can increase the friction between the palm of the user and the rotating handle 14, and prevent the user from slipping when rotating the rotating handle 14.

In some embodiments of this embodiment, an end cap of the casing 1 is provided with a clamping member 15, the clamping member 15 includes a circular clamping groove, one end of the casing 1 can extend into the circular clamping groove, the clamping member 15 is fixedly connected with the casing 1, and the clamping member 15 is connected with the fixing sleeve 4. Specifically, when fixed cover 4 and joint spare 15 fixed connection, because the structure on casing 1 is established to joint spare 15 cover, the phenomenon of droing can not appear usually in joint spare 15, and joint spare 15 is connected with fixed cover 4 moreover to can further consolidate the installation of fixed cover 4, thereby increase the service life of this current-limiting pump head.

When using this current-limiting pump head, the user needs to install this current-limiting pump head in the liquid outlet of liquid bottle, again according to self needs to adjust cover 3 and go on upwards or decurrent regulation. Specifically, when the user needs to increase the amount of liquid per pump, the rotation handle 14 is rotated clockwise so that the adjustment sleeve 3 moves downward, and when the user needs to decrease the amount of liquid per pump, the rotation handle 14 is rotated counterclockwise so that the adjustment sleeve 3 moves upward. After the adjusting sleeve 3 is adjusted to a proper position, a user presses the spray head 12, at the moment, the spring 6 is in a compressed state, the liquid inlet one-way valve 5 is in a closed state, the liquid outlet one-way valve is in an open state, and liquid in the inner chamber 16 is discharged from the pressing pipe 2 through the liquid outlet one-way valve. When the user releases his hand, the spring 6 will gradually return to the initial position, which in turn causes the pressure tube 2 and the spray head 12 to spring upwards. At this time, the liquid inlet check valve 5 is in an open state, the liquid in the bottle enters the inner chamber 16, and the liquid outlet check valve is in a closed state, so that the liquid can fill the inner chamber 16 to prepare for next liquid outlet.

It should be noted that rotating the rotating handle 14 counterclockwise moves the adjusting sleeve 3 upward to a position closest to the spray head 12. At this moment, adjusting sleeve 3 and shower nozzle 12 are laminated mutually for this pump head is in the off-state, and then makes the user press shower nozzle 12, presses pipe 2 and can not spray liquid, thereby can avoid causing liquid to splash owing to mistake touch shower nozzle 12.

To sum up, the embodiment of the utility model provides a current-limiting pump head, it includes pump core, casing 1, presses pipe 2 and adjusting collar 3, and the pump core sets up in casing 1. The inner wall of the shell 1 is provided with a fixed sleeve 4, the adjusting sleeve 3 extends into the fixed sleeve 4 and is in threaded connection with the fixed sleeve 4, and one end of the pressing pipe 2 penetrates through the adjusting sleeve 3 and is connected with the pump core for controlling the action of the pump core to discharge liquid. The other end of the pressing pipe 2 extends out of the shell 1, the pressing pipe 2 is in clearance fit with the adjusting sleeve 3, pressing through the pressing pipe 2 can be achieved, and the gap between the pressing pipe 2 and the adjusting sleeve 3 is favorable for gas flowing, so that the pressing pipe 2 is enabled to recover to a state before pressing as soon as possible. One end that the pressure pipe 2 stretches out the casing 1 is provided with shower nozzle 12, and shower nozzle 12 can not stretch into adjusting collar 3, and the setting of shower nozzle 12 can prevent because press excessively, press pipe 2 too to be absorbed in adjusting collar 3. In the above implementation, the pump head is usually installed above the bottle body. When using this pump head, according to user's actual conditions, adjust the height of adjusting collar 3, and then restrict the stroke of pressing of shower nozzle 12 to the realization is adjusted the extrusion volume of pump head, with the user demand that satisfies the user.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A flow-limiting pump head is characterized by comprising a pump core, a shell, a pressing pipe and an adjusting sleeve, wherein the pump core is arranged in the shell;

be provided with fixed cover on the inner wall of casing, the adjusting collar stretches into in the fixed cover, and with fixed cover threaded connection, the one end of pressing the pipe is passed the adjusting collar, and with the pump core is connected, it is used for control to press the pipe the action of pump core goes out the liquid, the other end of pressing the pipe stretches out the casing, press the pipe with adjusting collar clearance fit, it stretches out to press the pipe the one end of casing is provided with the shower nozzle.

2. The flow-limiting pump head of claim 1, wherein the pump core comprises a liquid inlet check valve, a spring, and a liquid outlet check valve sequentially disposed in the housing, the spring is disposed between the liquid inlet check valve and the liquid outlet check valve, one end of the spring is connected to the housing, the other end of the spring is connected to the liquid outlet check valve, and the liquid outlet check valve is connected to the pressing pipe.

3. A flow limiting pump head as defined in claim 2, wherein the housing includes a pipette connected to the intake check valve.

4. A flow-limiting pump head as claimed in claim 2, wherein the fluid outlet check valve includes a piston, the piston divides the housing into an inner chamber and an outer chamber, the piston is provided with a first through hole, the pressing tube can extend into the inner chamber along the first through hole, the pressing tube is slidably and sealingly connected to an inner wall of the first through hole, the pressing tube is provided with a second through hole, and the second through hole is communicated with the inner chamber.

5. A current limiting pump head according to claim 4, wherein a stop ring is provided within the outer chamber, the stop ring fitting over the pressure tube.

6. A flow-limiting pump head as recited in claim 4, wherein the housing defines a pressure balancing aperture, the pressure balancing aperture communicating with the outer chamber.

7. A flow limiting pump head as claimed in claim 1, wherein a nozzle is provided on the spray head, the nozzle communicating with the pressing tube.

8. A current limiting pump head as recited in claim 1, wherein an end of said adjustment sleeve extending beyond said housing is fitted with a rotatable handle.

9. A current limiting pump head as defined in claim 8, wherein the rotation handle is coated with an anti-slip layer.

10. A current limiting pump head as recited in claim 1, wherein a snap-in member is sleeved on an end of said housing, said snap-in member includes a circular slot, an end of said housing can extend into said circular slot, and said snap-in member is connected to said fixing sleeve.