Dispensing pump and fluid dispensing device

Abstract

A dispensing pump and a fluid dispensing device. The dispensing pump comprises a pump head (100), a pump core (200), and a suck-back device (300), wherein the pump core (200) comprises a housing (210) and a pump rod (220), and the pump head (210) is slidably connected to the pump rod (220) and can move between a first position and a second position relative to the pump rod (210); a mounting cavity (110) and a discharge channel (120) are formed in the pump head (100), the discharge channel (120) has an outlet (121), the top of the pump rod (220) and at least part of the suck-back device (300) are both located in the mounting cavity (110), the suck-back device (300) is connected to both the pump rod (220) and the pump head (100), the part of the mounting cavity (110) not occupied by the pump rod (220) and the suck-back device (300) is formed as a suck-back channel (111), and the suck-back channel (111) is in communication with the discharge channel (120); and the suck-back device (300) comprises an elastic portion (310), and the elastic portion (310) is configured to provide the pump head (100) an elastic force for making the pump head (100) move towards the first position. The dispensing pump can suck a fluid at the outlet back to a dispensing device, thereby avoiding residual fluid overflowing.

Description

Dispensing pump and fluid dispensing device TECHNICAL FIELD

[0001] The present application relates to the technical field of fluid dispensing, and more particularly to a dispensing pump for dispensing fluid from a container and a fluid dispensing device comprising the same. BACKGROUND

[0002] Dispensing pumps are commonly used in containers storing various fluids, such as personal care products, e.g. shampoo, shower gel, foundation, etc., pharmaceutical products, e.g. liquid medicine, etc., food fluids, etc. for dispensing the fluid in the container. The existing dispensing pump comprises a pump head and a pump core. In use, pressure is applied to the pump head by pressing, and the pump head transmits the pressure to the pump core. The pump core pumps the fluid in the container to the pump head under the action of the pressure, and the fluid is pumped out through the outlet of the pump head, thereby achieving fluid dispensing.

[0003] However, after the pump head is released (i.e. no longer pressed), the pressure will disappear, and at this time, some fluid will remain at the outlet of the pump head, or will overflow from the outlet under the action of gravity and residual pressure, thereby causing pollution to the pump head or the outside world. SUMMARY

[0004] In view of the above defects of the prior art, the purpose of the present application is to provide a dispensing pump and a fluid dispensing device to suck the fluid near the outlet of the pump head back into the dispensing pump after the pump head is released, thereby preventing the fluid from causing pollution.

[0005] To achieve the above purpose, in one aspect, the present application provides a dispensing pump, comprising a pump head, a pump core and a back-suction device, the pump core comprising a housing and a pump rod, the pump rod being in sliding connection with the housing, the pump head being in sliding connection with the pump rod and being movable relative to the pump rod between a first position and a second position;

[0006] An installation cavity and a discharge passage are formed in the pump head, the discharge passage having an outlet, the top of the pump rod and at least part of the back-suction device being located in the installation cavity, the back-suction device being connected to the pump rod and the pump head respectively, the part of the installation cavity not occupied by the pump rod and the back-suction device forming a back-suction passage, the volume of the back-suction passage gradually decreasing as the pump head moves from the first position towards the second position, the back-suction passage being in communication with the discharge passage;

[0007] The back-suction device comprises an elastic part, the elastic part being arranged to provide an elastic force to the pump head to move the pump head towards the first position, the elastic force causing the volume of the back-suction passage to increase when the pump head is released, so as to suck the fluid at the outlet back to the back-suction passage.

[0008] Further, the back-suction device further comprises a sealing part arranged between the pump rod and the pump head to form a seal between the pump rod and the pump head.

[0009] Further, the elastic part and the sealing part are formed as two independent parts and are fixedly connected with each other.

[0010] Further, the elastic part and the sealing part are formed as one body.

[0011] Further, the elastic part and the sealing part are integrally formed by two-color injection molding or insert injection molding with two materials or are integrally formed by injection molding with the same elastic material.

[0012] Further, when the elastic part and the sealing part are integrally formed by injection molding with the same elastic material, the thickness of the elastic part is less than the thickness of the sealing part.

[0013] Further, the sealing part is provided with a first limiting structure, and the inner wall of the pump head is provided with a second limiting structure, the first limiting structure and the second limiting structure cooperate to define the first position.

[0014] Further, the elastic part has an inner cavity, the inner cavity of the elastic part is in communication with the inner cavity of the pump rod and the discharge channel respectively, and the inner cavity of the elastic part is coaxially arranged with the mounting cavity of the pump head.

[0015] Further, the elastic part is formed with at least one through hole for communicating the inner cavity of the elastic part and the outside of the elastic part.

[0016] Further, the sealing part is detachably connected with the pump rod.

[0017] Further, the discharge channel is upwardly inclined.

[0018] Further, the discharge channel is a straight pipe or a bent pipe structure.

[0019] Further, the mounting cavity comprises a variable-volume space defined by the inner wall of the pump head and the elastic part, and the variable-volume space is arranged lower than the discharge channel.

[0020] Further, the plane formed at the outlet is arranged at an angle of 10°-40° with the vertical plane.

[0021] Further, a base is further included, the shell is fixed on the base, the shell is used for fixedly connecting with a container, the base is provided with a avoiding slot, the pump head is located in the avoiding slot and can move in the avoiding slot.

[0022] Another aspect of the present application provides a fluid dispensing device comprising a container having a receiving cavity for containing fluid and a dispensing pump as described above, wherein the housing of the pump core of the dispensing pump is fixedly connected to the top of the container directly or through a base, and the bottom of the housing of the pump core extends into the receiving cavity.

[0023] The dispensing pump and the fluid dispensing device of the present application can make the pump head move from the second position to the first position by the back-suction device when the pump head is released, and in this process, the volume of the back-suction channel will gradually increase and generate negative pressure, so as to suck the fluid near the outlet back to the recovery channel, avoiding the pollution caused by the residual fluid in or out of the outlet.

[0024] The concept, specific structure and technical effects of the present application will be further described below in combination with the drawings, so as to fully understand the purpose, features and effects of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0025] Fig. 1 is a structural schematic diagram of a dispensing pump according to an embodiment of the present application;

[0026] Fig. 2 is an exploded view of the dispensing pump of Fig. 1;

[0027] Fig. 3 is a top view of the dispensing pump of Fig. 1;

[0028] Fig. 4A is an A-A sectional view of Fig. 3;

[0029] Fig. 4B is an A-A sectional view of the dispensing pump of Fig. 3 when the pump head is pressed by external force and moves to the second position;

[0030] Fig. 5 is a structural schematic diagram of a back-suction device of the dispensing pump according to an embodiment of the present application;

[0031] Fig. 6 is a top view of a pump head of a dispensing pump according to another embodiment of the present application;

[0032] Fig. 7 is a B-B sectional view of Fig. 6;

[0033] Fig. 8 is a sectional view of a top view of a pump head of a dispensing pump according to still another embodiment of the present application;

[0034] Fig. 9 is a comparison diagram of back-suction effect of the pump head of the dispensing pump in an embodiment of the present application;

[0035] Fig. 10 is a structural schematic diagram of a dispensing pump with a base according to an embodiment of the present application;

[0036] Fig. 11 is a sectional view of the dispensing pump with the base of Fig. 10;

[0037] Fig. 12 is a structural schematic diagram of a fluid dispensing device according to an embodiment of the present application;

[0038] Figure 13 is an exploded view of the fluid dispensing device of Figure 12. DETAILED DESCRIPTION

[0039] In order to make the technical means, creative features, purposes and effects realized by the present application easy to understand, the present application is further described below in combination with specific drawings. However, the present application is not limited to the following cases.

[0040] It should be understood that the structures, proportions, sizes, etc. shown in the drawings attached to the present specification are only used to cooperate with the content disclosed in the present specification for understanding and reading by those skilled in the art, and do not define the limiting conditions for the implementation of the present application, and therefore do not have technical substantive significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the present application, should still fall within the scope of the technical content disclosed by the present application.

[0041] As shown in FIG. 1, FIG. 2, FIG. 3, FIG. 4A and FIG. 4B, the present application provides a dispensing pump for dispensing fluid from a container, the dispensing pump comprising a pump head 100, a pump core 200 and a back suction device 300, the pump core 200 comprising a housing 210 and a pump rod 220, the housing 210 being configured to be fixedly connected with the container and having a bottom portion extending into the container, the pump rod 220 being slidably connected with the housing 210, the pump head 100 being slidably connected with the pump rod 220, the pump head 100 being configured to be movable relative to the pump rod 220 between a first position and a second position, the pump head 100 having a mounting cavity 110 and a discharge passage 120 formed therein, the mounting cavity 110 being in communication with the discharge passage 120, the discharge passage 120 having an outlet 121, a top portion of the pump rod 220 extending into the mounting cavity 110, the back suction device 300 being at least partially disposed in the mounting cavity 110 and being connected with the pump head 100 and the pump rod 220 respectively, the pump rod 220 and the back suction device 300 defining a back suction passage 111 having a variable volume in the mounting cavity 110, i.e., the portion of the mounting cavity 110 not occupied by the pump rod 220 and the back suction device 300 forms the back suction passage 111, the back suction passage 111 being in communication with the discharge passage 120, the volume of the back suction passage 111 being a first volume when the pump head 100 is in the first position and being a second volume when the pump head 100 is in the second position, wherein the first volume is greater than the second volume; the back suction device 300 comprising an elastic portion 310, the elastic portion 310 being located in the mounting cavity 110 and being configured to apply an elastic force to the pump head 100 to move the pump head 100 towards the first position; in an initial state, the elastic force of the elastic portion 310 keeps the pump head 100 in the first position (see FIG. 4A), in use, the pump head 100 is movable from the first position towards the second position under the action of an external pressure (e.g., applied by a user), and the elastic portion 310 of the back suction device 300 is compressed in the process, in which the volume of the back suction passage 111 gradually decreases; when the pump head 100 moves to the second position (see FIG. 4B), the volume of the back suction passage 111 is minimized, i.e., the first volume is the maximum volume of the back suction passage 111, and the second volume is the minimum volume of the back suction passage 111, at the same time, the pressure on the pump head 100 is transmitted to the pump rod 220, and the pump rod 220 is moved downwards (e.g., to a third position) relative to the housing 210, the downward movement of the pump rod 220 pumps the fluid in the container through an inner cavity of the pump rod 220, and then through the back suction passage 111 and the discharge passage 120, and finally out of the outlet 121, thereby achieving the dispensing of the fluid.When the external force is removed, the pump head 100 will be released, the pump rod 220 will take the pump head 100 from the third position back to the second position, the fluid in the container will not flow out of the pump rod 220, then the pump rod 220 remains stationary, while the pump head 100 will continue to move from the second position to the first position under the elastic force of the elastic part 310, in the process, the volume of the back suction channel 111 will gradually increase, and a negative pressure will be generated, which will suck the fluid near the outlet 121 into the back suction channel 111, thereby realizing fluid back suction and avoiding contamination of the pump head 100 by residual fluid in the outlet 121.

[0042] In some embodiments, the back suction device 300 can further include a sealing part 320, which is clamped between the pump rod 220 and the inner wall 130 of the pump head 100 for defining the mounting cavity 110, and at least partially located in the mounting cavity 110, for forming a seal between the pump rod 220 and the inner wall 130 to prevent fluid from flowing out of the gap between the pump rod 220 and the inner wall 130.

[0043] In some embodiments, the elastic part 310 and the sealing part 320 can be formed as two independent parts, or the elastic part 310 and the sealing part 320 can be formed as one, i.e. as one part, or the elastic part 310 is formed as a separate part, and the sealing part 320 is formed as part of the pump rod 220.

[0044] When the elastic part 310 and the sealing part 320 are two independent parts, they can be fixedly connected together in any suitable manner, the sealing part 320 is fixed with the top of the pump rod 220, and the elastic part 310 is connected with the pump head 100 at the same time, so that the elastic part 310 applies an elastic force to the pump head 100. The elastic part 310 can be any form of elastic element, such as a spring, a spring piece, etc. When the elastic part 310 is a spring, its two ends can be in abutment with the sealing part 320 and the pump head 100 respectively, and in a compressed state, the pump head 100 and the sealing part 320 can be provided with grooves for accommodating the ends of the spring to prevent the spring from moving.

[0045] When the elastic portion 310 and the sealing portion 320 are formed integrally, the elastic portion 310 and the sealing portion 320 can be integrally formed by two-color injection molding or insert injection molding by two kinds of materials, or can be integrally formed by injection molding by the same elastic material. For example, the sealing portion 320 can be made of a material with smaller elasticity, and the elastic portion 310 can be made of a material with larger elasticity, so that when pressed, the elastic portion 310 can deform greatly and generate a reverse elastic force, and the sealing portion 320 deforms less and can be ignored, i.e., the sealing portion 320 can be approximately rigid. When the elastic portion 310 and the sealing portion 320 are made of the same elastic material, the thickness of the elastic portion 310 is less than the thickness of the sealing portion 320, so that the elastic portion 310 is easy to deform, and the sealing portion 320 is not easy to deform (i.e., approximately rigid). For example, the elastic portion 310 and the sealing portion 320 can be made of polyethylene material or polypropylene material, the sealing portion 320 is thicker, and the elastic portion 310 is thinner, so that the sealing portion 320 is approximately rigid, and the elastic portion 310 is easy to deform. It can be understood that, in addition to polyethylene material or polypropylene material, any suitable elastic material can be used, such as rubber, elastic plastic, spring steel, common metal springs, etc.

[0046] In some embodiments, the sealing portion 320 and the inner wall 130 of the pump head 100 are respectively provided with a first limiting structure 321 and a second limiting structure 131, and the first limiting structure 321 and the second limiting structure 131 cooperate with each other to define a first position of the pump head 100. For example, the first limiting structure 321 and the second limiting structure 131 can both be protrusions, and when the pump head 100 moves from the second position to the first position, the two protrusions abut and interfere with each other, so that the pump head 100 stops at the first position.

[0047] In some embodiments, the elastic part 310 can be a structure without an inner cavity, for example, a spring, or a structure with an inner cavity. When the elastic part 310 has an inner cavity, the inner cavity of the elastic part 310 is in communication with the inner cavity of the pump rod 220 and the discharge channel 120, respectively, and the elastic part 310 can also be in contact with and coaxial with the inner wall 130 of the pump head 100 (i.e., the inner cavity of the elastic part 310 and the mounting cavity 110 of the pump head 100 are coaxial), thereby ensuring that the pump head 100 is uniformly stressed and does not jam. As shown in FIG. 5, the diameter of the elastic part 310 can be gradually reduced from top to bottom, thereby forming a shape similar to a horn, which can be beneficial for fluid back suction. It can be understood that, in addition to the horn shape, the elastic part 310 can also be formed into any suitable shape of a revolving body with variable diameter (e.g., gradually reduced or gradually increased from top to bottom) or constant diameter. The elastic part 310 can also be formed with at least one through hole 311. When the pump head 100 moves between the first position and the second position, the elastic part 310 will elastically stretch and contract, causing the volume of the inner cavity of the elastic part 310 to change. The through hole 311 is used to communicate the inner cavity of the elastic part 310 with the outside, thereby balancing the internal and external pressures when the volume of the inner cavity of the elastic part 310 changes. At the same time, since the elastic part 310 separates the mounting cavity 110 into upper and lower parts, the through hole 311 can communicate the upper and lower parts, so that the back suction channel 111 includes the upper and lower parts, and the volume of the upper and lower parts will change during the movement of the pump head 100, thereby making the volume of the back suction channel 111 change more, and thus a greater back suction force can be generated, and the back suction effect is better.

[0048] The pump core 200 can adopt any suitable pump core in the prior art as long as it can pump fluid out of the container by pressing the pump rod 220. In a typical pump core 200, the housing 220 defines a pump cavity, and a piston, a spring, and a ball valve are arranged in the pump cavity. The pump rod 220, the piston, the spring, and the ball valve are connected in sequence, and the up and down movement of the pump rod 220 can make the piston move up and down, compress or release the spring, and change the volume of the pump cavity, thereby generating a suction force to suck fluid in the container into the pump cavity and then pump it out of the pump cavity through the pump rod 220.

[0049] In some embodiments, the sealing part 320 can be detachably connected with the pump rod 220, for example, the sealing part 320 can be sleeved outside the pump rod 220 and fixedly connected with the pump rod 220 through a buckle structure, thereby making the pump head 100 convenient to cooperate with various pump cores 200 in the prior art. Since the structure of the pump core 200 is relatively complex, if the pump core 200 is directly improved to have a back suction function, the cost is large. The present application does not need to modify the pump core 200, but only needs to add a back suction device 300 to the pump head 100 to make the dispensing pump have a back suction function, which is simple in structure and can greatly save costs.

[0050] In some embodiments, as shown in Figs. 6-8, the discharge channel 120 is upwardly inclined, which can be in a bent pipe structure (see Fig. 7) or a straight pipe structure (see Fig. 8), and the outlet 121 of the discharge channel 120 is also upwardly inclined, and the angle a between the plane formed by the outlet 121 and the vertical plane is 10°-40°. The installation cavity 110 includes a variable volume space defined by the inner wall 130 and the elastic part 310, which is arranged below the discharge channel 120. When the external pressure acts on the pump head 100 to move it from the first position to the second position, the elastic part 310 is compressed and deformed, and at this time, as the external pressure continues to act, the variable volume space gradually decreases, and when the pump head 100 moves to the second position, the variable volume space becomes the smallest; when the external force is removed to release the pump head 100, the pump head 100 will move from the second position to the first position under the elastic force of the elastic part 310, and at this time, the variable volume space gradually increases, which generates a negative pressure to suck the fluid near the outlet 121, and because the variable volume space is located below the discharge channel 120, a greater suction force is generated, so that the upwardly inclined discharge channel 120 can suck the fluid, and at the same time, the fluid is prevented from remaining at the outlet 121 to contaminate the pump head 100.

[0051] Fig. 9 shows the fluid suction effect comparison diagram when the angle a between the plane formed by the outlet 121 of the pump head 100 and the vertical plane is 0°-40°. In this embodiment, the discharge channel 120 is in a bent pipe structure, and Fig. 9 shows, from top to bottom, the cross-sectional view of the outlet 121 with different angles a, the partial cross-sectional view of the discharge channel 120 with different angles a, the pump head sample with different angles a, and the pump head suction effect with different angles a. In the last row of the pump head suction effect comparison diagram with different angles a, the fluid wall-hanging residual area after fluid suction can be clearly seen, wherein when the angle a is 0°, the fluid wall-hanging is obvious, the residual is more, and the contamination of the pump head outlet is more, and the fluid suction effect is poor at this angle; when the angle a is increased to 10°, the fluid wall-hanging residual area is obviously reduced; when the angle a is increased to 20°, the fluid wall-hanging residual area is reduced more, and at this time, the fluid suction state is more ideal; when the angle a is continuously increased to 30°, the fluid wall-hanging residual area is smaller, and at this time, the fluid suction effect is still good; when the angle a is 40°, the end face area formed by the outlet 121 is larger at this angle, so that the fluid wall-hanging residual area is slightly increased, but the fluid suction effect is still good. From the foregoing comparison, it can be seen that when the angle a is 10°-40°, a greater suction force is generated to suck the fluid near the outlet, and to prevent the fluid from remaining at the outlet or overflowing from the outlet to cause contamination.

[0052] As shown in FIG. 10 and FIG. 11, the dispensing pump can further comprise a base 400 for fixed connection with the container, the housing 210 is fixed on the base 400, the base 400 is provided with a recess 410, the pump head 100 is located in the recess 410 and can move up and down in the recess 410, so as to avoid the interference between the pump head 100 and the base 400 during the movement. By providing the base 400, on the one hand, the dispensing pump can be better connected to the container, on the other hand, the base 400 can cover the pump head 100, the pump core 200 and the connection therebetween, so as to make the dispensing pump more beautiful.

[0053] In some embodiments, the fluid can be personal care products, food, medicine or any other suitable fluid product, so that the dispensing pump can be applied to various fields.

[0054] The dispensing pump of the embodiments of the present application, when the pump head 100 is released, the back suction device 300 can move the pump head 100 from the second position to the first position, in the process, the volume of the back suction channel 111 will gradually increase and generate negative pressure, so as to suck the fluid near the outlet 121 back to the recovery channel 111, avoiding the contamination of the pump head 100 by the residual fluid in the outlet 121.

[0055] As shown in FIG. 12 and FIG. 13, the embodiments of the present application further provide a fluid dispensing device, which comprises a container 500 and a dispensing pump as described in the above embodiments, wherein the container 500 has a containing cavity 510 for containing fluid, the housing 210 of the pump core 200 of the dispensing pump is directly or through the base 400 fixedly connected with the top of the container 500, and the bottom of the housing 210 of the pump core 200 extends into the containing cavity 510. The base 400 and the container 500 can be connected by screw threads.

[0056] The fluid dispensing device of the embodiments of the present application adopts the dispensing pump of the above embodiments, so that the back suction of the fluid can be realized, and the contamination caused by the residual fluid in the outlet 121 or the overflow of the fluid from the outlet 121 can be prevented.

[0057] The above describes the preferred embodiments of the present application in detail. It should be understood that those skilled in the art can make many modifications and changes without creative labor based on the concept of the present application. Therefore, any technical solution obtained by logical analysis, reasoning or limited experiment based on the prior art according to the concept of the present application shall be within the protection scope determined by the claims.

Claims

1. A dispensing pump characterized by, The pump comprises a pump head, a pump core and a back suction device, the pump core comprises a shell and a pump rod, the pump rod is in sliding connection with the shell, the pump head is in sliding connection with the pump rod and can move relative to the pump rod between a first position and a second position; An installation cavity and a discharge channel are formed in the pump head, the discharge channel has an outlet, the top of the pump rod and at least part of the back suction device are located in the installation cavity, the back suction device is connected with the pump rod and the pump head respectively, the part of the installation cavity not occupied by the pump rod and the back suction device is formed into a back suction channel, the volume of the back suction channel gradually decreases as the pump head moves from the first position to the second position, the back suction channel is in communication with the discharge channel; The back suction device comprises an elastic part, the elastic part is arranged to provide an elastic force to the pump head to move the pump head to the first position, the elastic force makes the volume of the back suction channel increase when the pump head is released to suck the fluid at the outlet back to the back suction channel.

2. The dispensing pump of claim 1, wherein The back suction device further comprises a sealing part, the sealing part is arranged between the pump rod and the pump head to form a seal between the pump rod and the pump head.

3. The dispensing pump of claim 2, wherein, The elastic part and the sealing part are formed as two independent parts and are fixedly connected with each other.

4. The dispensing pump of claim 2, wherein, The elastic part and the sealing part are formed as one body.

5. The dispensing pump of claim 4, wherein, The elastic part and the sealing part are integrally formed by two-color injection molding or insert injection molding with two materials or are integrally formed by injection molding with the same elastic material.

6. The dispensing pump of claim 5, wherein, When the elastic part and the sealing part are integrally formed by injection molding with the same elastic material, the thickness of the elastic part is smaller than the thickness of the sealing part.

7. The dispensing pump of claim 2, wherein, A first limiting structure is arranged on the sealing part, a second limiting structure is arranged on the inner wall of the pump head, and the first limiting structure and the second limiting structure cooperate with each other to define the first position.

8. The dispensing pump of claim 1, wherein, The elastic part has an inner cavity, the inner cavity of the elastic part is in communication with the inner cavity of the pump rod and the discharge channel respectively, and the inner cavity of the elastic part is coaxially arranged with the installation cavity of the pump head.

9. The dispensing pump of claim 8, wherein, At least one through hole is formed on the elastic part, and the through hole is used to communicate the inner cavity of the elastic part and the outside of the elastic part.

10. The dispensing pump of claim 2, wherein, The sealing part is detachably connected with the pump rod.

11. The dispensing pump of claim 1, wherein The discharge channel is upwardly inclined.

12. The dispensing pump of claim 11, wherein, The discharge channel is in a straight pipe or elbow structure.

13. The dispensing pump of claim 11, wherein, The installation cavity comprises a variable volume space defined by the inner wall of the pump head and the elastic part, and the variable volume space is arranged lower than the discharge channel.

14. The dispensing pump of claim 11, wherein, A plane formed at the outlet is arranged at an angle of 10°-40° with a vertical plane.

15. The dispensing pump of claim 1, wherein, A base is further provided, the shell is fixed on the base, the shell is used to be fixedly connected with a container, an avoiding groove is arranged on the base, the pump head is located in the avoiding groove and can move in the avoiding groove.

16. A fluid dispensing device characterized by, A container and a dispensing pump according to any one of claims 1-15 are further provided, the container has a containing cavity for containing fluid, the shell of the pump core of the dispensing pump is fixedly connected with the top of the container directly or through the base, and the bottom of the shell of the pump core extends into the containing cavity.

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