WO2013097466A1

WO2013097466A1 - Press type liquid pump

Info

Publication number: WO2013097466A1
Application number: PCT/CN2012/080201
Authority: WO
Inventors: 丁要武
Original assignee: Ding Yaowu
Priority date: 2011-12-27
Filing date: 2012-08-16
Publication date: 2013-07-04
Also published as: CN103182351A; JP2015509888A; CN103182351B

Abstract

A press type liquid pump comprises a pressure head (10), a plunger (50), an upper one-way valve (40), a liquid storage tank (30) and a lower one-way valve (80). The pressure head (10) is connected with the plunger (50). The lower one-way valve (80) is installed at the bottom of the liquid storage tank (30). The pressure head (10) and the plunger (50) form a distribution channel of a liquid product together. A volume change device is provided at the bottom of the pressure head (10) or the plunger (50). The volume of the distribution channel is reduced during the process that the pressure head (10) is pressed downwards and is restored the original state of the volume after the downward pressing action is withdrawn. The liquid pump can effectively prevent the residual liquid product inside the distribution channel from dropping from an outlet portion of the pressure head.

Description

Press type liquid pump

This invention relates to the field of liquid pumps, and more particularly to a push-type liquid pump. Background technique

The liquid pump is typically mounted at the opening of the container for pumping the liquid product within the container out of the container for use by a user's manual pressing operation. Figure 1 shows a conventional push type liquid pump. In this liquid pump, the lower check valve 180 is closed during the downward pressing of the pump head 110 by the user, and the check valve 140 is closed (the one-way valve is an outer peripheral surface of the piston rod 152 (as a valve seat) And the piston member 141 (as a valve member) mounted on the outer peripheral surface is opened, and the liquid product in the reservoir 130 in the cylinder 160 passes through the open upper check valve 140 and passes through the piston 150 (the piston is The piston rod 152 is formed of a piston member 141 mounted on the piston rod 152, wherein the piston rod 152 and the piston member 141 simultaneously serve as members constituting the one-way valve 140 and the piston 150, that is, the check valve 140 is a part of the piston 150. The delivery passage 151 and the discharge passage 111 of the ram 110 are pumped out, and the delivery passage 151 and the discharge passage 111 constitute a distribution passage for the liquid product to be pumped from the reservoir 130 to the outside of the container; when the user removes After the downward pressing of the indenter 110, the indenter 110 returns to its original position under the action of the elastic resetting device 120, and during the resetting of the indenter 110, the lower check valve 180 is opened, and the upper check valve is opened. 140 is closed and the liquid product in the container is drawn into the reservoir 130 through the open lower check valve 180 for the next pumping dispense. Typically, the distribution passage is located between the upper one-way valve 140 and the outlet portion 112 of the ram 110.

The design of such prior art liquid pumps described above has a disadvantage. Specifically, after each pumping and dispensing operation of the liquid pump is completed, a liquid product remains in the outlet portion of the indenter, and the residual liquid product may drip onto the surface of the container or on the container itself, especially In the process of moving or placing the container. For liquid products with low viscosity and good fluidity (such as oily or watery products), even if the container does not move without vibration, the residual liquid product near the outlet of the indenter after a period of time will be self-gravated by gravity. Dropping, causing undesired pollution problems. Summary of the invention

In view of the above problems in the prior art, the main object of the present invention is to provide a A suction pump that prevents the product from dripping.

In order to achieve the above object of the present invention, according to the present invention, there is provided a push type liquid pump for mounting to a container for pumping a liquid product in the container to the outside of the container, the liquid pump comprising a pressure head of the outlet portion, a piston connected to the pressure head, an upper check valve, a liquid storage tank, and a lower one-way valve disposed at the bottom of the liquid storage tank, from the upper one-way valve to the outlet of the pressure head a portion defining a distribution passage for the liquid product, the upper one-way valve controls communication between the distribution passage and the liquid storage tank, and the lower one-way valve controls the liquid storage tank and the interior of the container In communication, during the pressing of the indenter, the upper one-way valve is opened and the lower one-way valve is closed, and the liquid product passes through the open upper one-way valve and passes through the distribution passage The liquid storage tank is pumped and distributed to the outside of the container, and the upper check valve is closed and the order is closed during the process of removing the downward pressing action to reset the pressure head and the piston upward. Open to the valve, the liquid product is opened by the a lower check valve is drawn from the interior of the container into the reservoir for the next press pumping dispense, characterized in that the liquid pump comprises means for reducing the press head during the downward press The volume changing means for the volume of the distribution channel and the volume of the distribution channel to be restored to the original state after the downward pressing action is removed.

With the liquid pump of the present invention, since the volume changing means for reducing the volume of the distribution passage during the downward pressing of the indenter and returning the volume of the distribution passage after the pressing action is removed is employed, After the pumping operation is pressed, the returning elastic deformation of the volume changing device generates a negative pressure, and at this time, as is known to those skilled in the art, since the distribution passage is open only to the outside atmosphere at the outlet portion of the indenter, the air is The outlet portion is replenished into the dispensing passage such that the residual liquid product adjacent the outlet portion is drawn inward toward the volume changing device. Therefore, the liquid product is not substantially left in the vicinity of the outlet portion of the indenter, so that the leakage of the residual liquid product in the distribution passage from the outlet portion of the indenter can be effectively prevented.

According to the present invention, the volume changing device may include a pressing sheet at a pressed portion of the ram for engaging a user's hand applying the downward pressing action, the pressing sheet directly relating to the dispensing The channels are associated with each other, and the pressing sheet is adapted to elastically deform into the distribution channel to reduce the volume of the dispensing channel under the downward pressing of the user, and the pressing sheet is removed after the downward pressing action is removed It is suitable for elastic recovery of its original shape to restore the volume of the distribution channel to its original state. Since the volume changing device is a pressing sheet that engages with the user's hand, it is possible to easily change the volume of the dispensing channel while performing the push pumping, without requiring a separate operation to perform the required volume change, thereby enabling the user The operation is simpler. According to the invention, the pressing sheet may be integrally formed with the ram or may be a separate member attached to the ram. For integral formation, it can be produced by gas-assisted molding technology or injection molding machine when injecting the indenter, which can increase the area of the pressed deformation part (ie, pressing the sheet), increase the volume change degree, and at the same time solve the ordinary injection mold. The core should not be too big a problem. In addition, the pressing of the pressing sheet and the indenter integrally reduces the number of parts, omits the corresponding assembly process, and also avoids leakage problems that may occur at the joint of the parts.

According to the present invention, in the case where the volume changing means is a pressing sheet for being engaged with the user's hand at the pressed portion of the ram, the pressing sheet may have an upward arch shape. By forming the pressing sheet into an arch shape, it is advantageous to improve the deformation resetting property of the pressing sheet and to increase the degree of volume change.

According to the present invention, the liquid pump may include an elastic returning means for resetting the ram and the piston after the user's pressing force is removed. In this case, the indenter and piston can be automatically reset by the elastic reset device without the need to manually reset the indenter and piston.

According to the invention, in the case where the elastic return means comprises a compression spring acting on the bottom of the piston opposite to the pressing direction, the volume changing means may comprise a compression at the bottom of the piston and the compression An elastic sheet engaged at an upper end of the spring, the elastic sheet being directly coupled to the dispensing passage, the elastic sheet being adapted to be in the reaction of the compression spring during the pressing of the ram The elastic deformation in the distribution channel reduces the volume of the distribution channel, and after the downward pressing action is removed, the elastic sheet is adapted to elastically restore its original shape to restore the volume of the distribution channel to its original state. Since the volume changing means is an elastic sheet which is located at the bottom of the piston and engages with one end of the compression spring, the volume of the distribution passage can be easily changed by the reaction force of the compression spring while performing the push pumping, without using a separate The operation is done to accomplish the required volume change, thereby making the user's operation simple.

According to the invention, the elastic sheet is integrally formed with the piston, and may also be a separate member attached to the piston. The integral formation reduces the number of parts, eliminates the need for assembly steps, and avoids possible leaks at the joints of the parts.

According to the invention, in the case where the volume changing means is an elastic sheet located at the bottom of the piston and engaged with one end of the compression spring, the elastic sheet may have a downward arch shape. By forming the elastic sheet into an arch shape, it is advantageous to improve the deformation reset performance of the pressing sheet and to increase the degree of volume change. Other features and advantages of the invention will be apparent from the following description of exemplary embodiments. DRAWINGS

Figure 1 is a cross-sectional view of a prior art push-type liquid pump;

Figure 2 is a cross-sectional view showing the position of the push-type liquid pump of the first embodiment of the present invention at the top dead center of the pressing stroke;

Figure 3 is a cross-sectional view of the liquid pump of Figure 2 during a depression process;

Figure 4 is a cross-sectional view of the liquid pump of Figure 2 during resetting;

Figure 5 is a cross-sectional view of the liquid pump of Figure 2 after resetting;

Figures 6a, 6b, 6c and 6d show the pressing sheets used in the liquid pump of Figure 2, which are respectively a front view, a cross-sectional view, a top view and a perspective view of the pressing sheet;

Figures 7a, 7b and 7c show the indenters used in the liquid pump of Figure 2, which are respectively a cross-sectional view, a perspective view and a top view of the indenter;

Figure 8 is a schematic view showing the assembly of the pressing sheet and the indenter in Figures 6 and 7;

Figure 9 is a cross-sectional view showing a modification of the liquid pump of the first embodiment, wherein the liquid pump is at a top dead center position of the pressing stroke;

Figure 10 is a cross-sectional view of the liquid pump of Figure 9 during a depression process;

Figure 11 is a cross-sectional view showing the position of the push-type liquid pump of the second embodiment of the present invention at the top dead center of the pressing stroke;

Figure 12 is a cross-sectional view of the liquid pump of Figure 11 at a dead center position of the pressing stroke;

Figures 13a, 13b, 13c and 13d show piston heads with elastic sheets used in the liquid pump of Figure 11, which are respectively a front view, a cross-sectional view, a top view and a perspective view of the piston head;

Figure 14 is a view showing a modification of the piston head used in the liquid pump of the second embodiment, wherein the elastic sheet is fitted to the piston head;

Figure 15 is a cross-sectional view showing the piston head of Figure 14 in a state in which an elastic sheet is assembled;

16a, 16b, 16c, and 16d are a front view, a cross-sectional view, a top view, and a perspective view, respectively, of the piston head of Fig. 14 in a state in which the elastic sheet is not assembled;

17a, 17b, 17c, and 17d are front, cross-sectional, top, and perspective views, respectively, of an elastic sheet assembled to the piston head of Fig. 14. detailed description

First of all, by the way, the "upper", "lower", "top" and "bottom" described in the context are placed in a vertical orientation relative to the push-type liquid pump (ie the liquid pump is set to its axis) The orientation in the vertical direction, which is the usual orientation of the push-type liquid pump during operation, is determined.

Referring to Figures 2-8, a first embodiment of the present invention is shown. The push-type liquid pump mainly comprises a ram 10, a volume changing device mounted on the ram 10, and a piston 50 connected to the ram 10 (the piston is composed of a piston rod 52 and a piston member 141 mounted on the piston rod 52) a cylinder 60 forming a reservoir 30, and an upper check valve 40 disposed on the piston 50 (the upper check valve is an outer peripheral surface of the piston rod 52 (as a valve seat) and a piston member mounted on the outer peripheral surface 141 (as a valve member) is constructed in which a piston rod 52 and a piston member 41 are simultaneously used as members constituting the one-way valve 40 and the piston 50, that is, the check valve 40 is provided as a part of the piston 50), and is disposed in the liquid storage A lower check valve 80 at the bottom of the tank 30, an elastic return device 20 acting on the bottom of the piston 50, and an integral mouthpiece-cylinder head 70 for attachment to the container. The center of the piston rod 52 of the piston 50 forms a delivery passage 51 in which a discharge passage 11 terminating in the outlet portion 12 of the ram is formed. The delivery passage 51 and the discharge passage 11 together constitute a pumping distribution of the liquid product from the reservoir 30. The distribution channel to the outside of the container, that is, the distribution channel is located between the upper check valve 40 and the outlet portion 12 of the ram 10. The basic structure of the push type liquid pump and its working principle are well known in the art except for the volume changing means, so the details of the known structure and operation will not be described below.

In this embodiment, the volume changing device of the present invention is a pressing sheet 15 attached to the top pressed portion of the ram 10. The pressing sheet 15 is generally upwardly arched and may be of the same material as the material of the indenter 10 or a more elastic elastomeric material. As shown in Figures 6a-6d, the pressing sheet 15 includes an arched sheet portion 17 and an annular base portion 16 extending from the lower edge of the sheet portion 17. The base portion 16 is for snapping into a corresponding annular notch 13 formed in the ram 10, as shown in Figures la-Ίά and 8, whereby the pressing sheet 15 is mounted to the ram 10. Preferably, the inner wall of the base 16 may be formed with annular ribs 18 that cooperate with corresponding recesses 14 in the slots 13 of the ram 10 to facilitate secure attachment of the base 16 within the slots 13.

At the top end position of the pressing stroke shown in Fig. 2, the ram 10 is not pressed, and at this time, the pressing sheet 15 assumes its original arched state. In the process in which the user presses the ram 10 downward to move downward with respect to the cylinder 60 together with the piston 50 and the upper check valve 40, as shown in FIG. 3, the pressing sheet 15 is pressed. It is flattened toward the inside of the distribution channel by pressing down, thereby reducing the volume of the distribution channel. At this time, the lower check valve 80 is closed, the upper check valve 40 is opened, and the liquid product in the reservoir 30 is pumped out through the open upper check valve 40 and through the distribution passage.

When the user removes the downward pressing action on the ram 10, as shown in Fig. 4, the ram 10 together with the piston 50 and the upper check valve 40 is in the elastic returning device 20 (in this embodiment, a compression spring) ) returns to its original position. During this reset, the lower check valve 80 is opened, the upper check valve 40 is closed, and the liquid product in the container is drawn into the reservoir 30 through the open lower check valve 80 for the next pumping dispense. At the same time, the pressing sheet 15 returns to its original arched state, thereby increasing the volume of the dispensing passage. At this time, since the upper one-way valve 40 is closed, the dispensing passage passes only through the outlet portion 12 of the ram 10 and the outside atmosphere. The same. Therefore, under the action of the negative pressure generated by the pressing sheet 15, air is replenished from the outlet portion 12 into the distribution passage, so that the residual liquid product located near the outlet portion 12 is sucked inward in the direction of the arrow A, thus, the ram outlet portion 12 There is no residual liquid product in the nearby discharge passage 11, as shown in Fig. 5, thereby effectively avoiding inadvertent dripping of the liquid product.

The degree of deformation of the sheet portion 17 of the pressing sheet 15 can be set by a technician depending on the specific conditions (e.g., including the viscosity of the liquid product, the geometry of the discharge passage of the indenter, etc.) to achieve the desired degree of volume change.

Further, in the first embodiment, the piston rod 52 is formed in a split type, which is different from the piston 152 of the one-piece structure shown in Fig. 1. Specifically, the piston rod 52 is connected by the piston rod main body 54 located at the upper portion and the piston head 53 located at the lower portion, and the final structure of the piston rod 52 thus connected is substantially identical to the structure of the piston rod 152 of Fig. 1. The use of either a split or a one-piece piston rod does not affect the practice of the present invention.

Figures 9-10 illustrate a variation of the first embodiment of Figures 2-8 wherein the pressing tab 15' is an integral part of the ram. In this modification, the pressing sheet 15' does not have the base portion 16 of the pressing sheet 15 of the foregoing embodiment but only in the shape of the sheet portion 17; accordingly, it is not necessary to form the notch 13 on the ram 10'. The pressing sheet 15' can be produced, for example, by using a gas-assisted molding technique or a blow molding machine during the injection molding of the ram. Compared with the separately provided pressing sheet 15 of the foregoing embodiment, the integrally formed pressing sheet 15' is advantageous in reducing the number of parts, eliminating the corresponding assembly process, and also avoiding leakage problems which may occur at the joint of the parts. Since the rest of the structure and the working mode of the modification are the same as those of the foregoing embodiment, they will not be described herein.

Referring to Figures 11-12, a second embodiment of the present invention is shown. Implemented as shown in Figure 2-8 above For example, the push-type liquid pump mainly comprises an indenter 210, a piston 250 connected to the indenter 210, a cylinder 260 forming a liquid storage tank 230, an upper one-way valve 240 disposed on the piston 250, and disposed in the liquid storage tank 230. A lower one-way valve 280 at the bottom, an elastic return device 220 acting on the bottom of the piston 250, and an integral braces-cylinder head 270 for attachment to the container. The piston 250 is composed of a piston rod 252 and a piston member 241 mounted on the piston rod 252. The center of the piston rod 252 of the piston 250 forms a delivery passage 251 in which a discharge passage 211 is formed which terminates in the outlet portion 212 of the ram. The delivery passage 251 and the discharge passage 211 together constitute a pumping distribution of the liquid product from the reservoir 230. The distribution channel to the outside of the container, that is, the distribution channel is located between the upper one-way valve 240 and the outlet portion 212 of the ram 210. The difference is that, in the present embodiment, the volume changing means is not disposed on the ram 210, but is disposed at the bottom of the piston 250 to be engaged with the elastic returning device 220.

In this embodiment, the piston rod 252 is composed of two parts, that is, a piston rod main body 254 located at the upper portion and a piston head 253 located at the lower portion, and the piston is inserted by inserting the lower end of the piston rod main body 254 into the upper end of the piston head 253. The rod body 254 and the piston head 253 are coaxially coupled to each other to form a piston rod 252. The upper check valve 240 is preferably disposed at a joint of the piston rod main body 254 and the piston head 253 by an outer peripheral surface of the piston rod 252 (as a valve seat) and a piston member 241 mounted on the outer peripheral surface (as Valve member). The piston head 253 constitutes a bottom portion of the piston 250, which is formed with an elastic sheet 255 for closing the lower end of the conveying passage 251, and the elastic sheet 255 constitutes the volume changing means of the present invention.

As shown in Figs. 13a-13d, the piston head 253 is substantially cylindrical, and an inner groove of the upper end portion thereof is preferably formed with an annular groove 263 for corresponding to the outer wall of the lower end portion of the piston rod main body 254. The annular ribs cooperate to facilitate the fixed attachment of the piston head 253 to the piston rod body 254. The elastic sheet 255 is integrally formed laterally on the piston head 253 to block the center passage of the cylindrical piston head 253. The elastic sheet 255 is generally downwardly arched for elastic deformation while facilitating abutment against one end of the compression spring 220.

At the top end position of the pressing stroke shown in Fig. 11, the ram 210 is not pressed, and the elastic sheet is at this time.

255 assumes its original arched state. During the downward pressing of the ram 210 by the user to move downwardly with respect to the cylinder 260 along with the piston 250 and the upper check valve 240, as shown in FIG. 12, the elastic sheet 255 is gradually subjected to the compression spring 20. The increased upward reaction force flattens toward the distribution channel, thereby reducing the volume of the distribution channel. At this time, the lower check valve 280 is closed, the upper check valve 240 is opened, and the liquid product in the reservoir 230 is pumped out through the open upper check valve 240 and through the distribution passage. When the user removes the downward pressing action on the ram 210, the ram 210, together with the piston 250 and the upper check valve 240, returns to their original position under the action of the compression spring 220. During this reset, the lower check valve 280 opens, the upper check valve 240 closes, and the liquid product in the container is drawn into the reservoir 230 through the open lower check valve 280 for the next pumping dispense. At the same time, since the reaction force of the compression spring 220 is reduced, the elastic sheet 255 returns to its original arched state, thereby increasing the volume of the distribution passage, and at this time, since the upper check valve 240 is closed, the distribution passage is only The outlet portion 212 of the indenter 210 is open to the outside atmosphere. Therefore, under the action of the negative pressure generated by the pressing sheet 255, the air is replenished from the outlet portion 212 into the distribution passage, so that the residual liquid product located near the outlet portion 212 is sucked inward, and there is no residual in the vicinity of the ram outlet portion 212. Liquid products, thus effectively avoiding dripping of liquid products.

As with the pressing sheet 15 of the first embodiment, the degree of deformation of the elastic sheet 255 can be set by a technician according to a specific case (for example, factors including the viscosity of the liquid product, the geometry of the discharge passage of the indenter, etc.). The degree of volume change required.

Figures 14-17 illustrate a variation of the second embodiment of Figures 11-12 wherein the resilient sheet 255' is comprised of a separate component that is coupled to the lower end of the piston head 253'. Unlike the embodiment shown in Figs. 11-12, in this modification, the upper end 254' of the piston head 253' is inserted in the lower end of the piston rod body (not shown). The elastic sheet 255' is connected to the lower end 256' of the piston head 253'.

As shown in Figures 17a-17d, the elastic sheet 255' includes an arched sheet portion 257' and an annular base 258' extending vertically from the upper edge of the sheet portion 257'. The base 258' is for snapping into a corresponding socket 26 formed at the lower end of the piston head 253', as shown in Fig. 15, thereby mounting the elastic sheet 255' to the piston head 253'. Preferably, the outer wall of the base 258' may be formed with an annular rib 259 that cooperates with a corresponding recess 262' formed in the socket 26 of the piston head 253' to facilitate the base 258' at the socket 26. Reliable fixation inside.

Since the rest of the structure and operation of the modification are the same as those of the foregoing second embodiment, they will not be described herein.

The invention has been described above by way of a description of the exemplary embodiments thereof, and it is obvious to those skilled in the art that various modifications can be made to the embodiments shown. For example, in the illustrated embodiment, the volume changing device is formed by a pressing sheet disposed on the ram or an elastic sheet disposed on the piston head, but it may also be provided by other suitable portions disposed on the dispensing passage. Characteristic composition (for example, by providing the piston rod to have a certain flexibility in the vertical direction) The volume change device). For another example, in the illustrated embodiment, the distribution passage is formed by the indenter and the piston rod, but it may also be formed only by the indenter (for example, the upper one-way valve may be disposed at the top of the piston). For another example, in the illustrated embodiment, the pressing sheet or the elastic sheet is arched, but it may be of other suitable shape (e.g., a substantially flat shape) as long as there is sufficient space for elastic deformation thereof. As another example, in the illustrated embodiment, the resilient return means is a compression spring, but it can be other forms of resilient means (such as an elastic bellows). As another example, in the illustrated embodiment, the pistons are each assembled from separate piston rods and piston heads, but they can also be made in one piece, as shown in FIG. Also for example, in the illustrated embodiment, the upper check valve is formed as a part of the piston from an outer peripheral surface of the piston rod and a piston member mounted on the outer peripheral surface, but it may also be a separate piston Formal check valve. Therefore, the scope of the invention is not limited to the specific embodiments described, but the scope of the appended claims.

Claims

Claim

CLAIMS 1. A push-type liquid pump for mounting to a container for pumping a liquid product within the container to the exterior of the container, the liquid pump comprising an indenter having an outlet portion, connected to the indenter a piston, an upper check valve, a liquid storage tank, and a lower one-way valve disposed at a bottom of the liquid storage tank, and an outlet passage from the upper one-way valve to the pressure head defines a distribution passage of a liquid product, An upper check valve controls communication between the distribution passage and the liquid storage tank, and the lower check valve controls communication between the liquid storage tank and the interior of the container, and the pressure head is pressed downward During the process, the upper one-way valve is opened and the lower one-way valve is closed, and the liquid product is pumped from the liquid storage tank through the upper one-way valve and distributed through the distribution passage to the Outside the container, the upper check valve is closed and the lower check valve is opened during the process of removing the pressing force to reset the pressure head and the piston upward, and the liquid product is opened by the a lower check valve is drawn from the interior of the container into the reservoir for Sub-pumping pumping dispensing, characterized in that the liquid pump comprises means for reducing the volume of the dispensing channel during the downward pressing of the indenter, while at the same time removing the downward pressing action The volume changing device of the volume of the distribution channel is restored to the original state.

The push type liquid pump according to claim 1, wherein the volume changing means is provided at a pressed portion of the ram for engaging a user's hand applying the downward pressing action Pressing a sheet directly associated with the dispensing channel, the pressing sheet being adapted to elastically deform within the dispensing channel to reduce the volume of the dispensing channel under the user's downward pressing, The pressing sheet is adapted to elastically restore its original shape after the downward pressing action is removed to restore the volume of the dispensing passage to its original state.

The push type liquid pump according to claim 2, wherein the pressing sheet is integrally formed with the pressing head.

The push type liquid pump according to claim 2, wherein the pressing sheet is a separate member connected to the indenter.

The push type liquid pump according to claim 2, wherein the pressing sheet has an upward arch shape.

The push type liquid pump according to claim 1, wherein the liquid pump includes elastic return means for resetting the ram and the piston after the downward pressing is removed.

The push type liquid pump according to claim 6, wherein the elastic reset device package a compression spring acting on a bottom of the piston opposite to the direction of the downward pressing, the volume changing device comprising an elastic sheet at a bottom of the piston to engage an upper end of the compression spring, The elastic sheet is directly connected to the distribution channel, and the elastic sheet is adapted to elastically deform into the distribution channel to reduce the deformation of the compression channel during the downward pressing of the pressure head. The volume of the distribution channel is adapted to elastically restore its original shape after the downward pressing action is removed to restore the volume of the distribution channel to its original state.

The push type liquid pump according to claim 7, wherein the elastic sheet is integrally formed with the piston.

The push type liquid pump according to claim 7, wherein the elastic sheet is a separate member that is coupled to the piston.

The push type liquid pump according to claim 7, wherein the elastic sheet has a downward arch shape.