Plastic elastic reset mechanism and press pump comprising same

Abstract

A plastic elastic reset mechanism (50). The plastic elastic reset mechanism (50) is applied in a press pump (1), and comprises at least one elastic strip (51). The elastic strip (51) comprises an interface, and the interface divides the elastic strip (51) into an inner portion (54) and an outer portion (55), wherein when the elastic strip (51) is deformed under pressure, the inner portion (54) is subjected to a compressive force, the outer portion (55) is subjected to a tensile force, and the force applied to the interface of the elastic strip (51) is zero. In a same cross section of the elastic strip (51), the cross-sectional area of the inner portion (54) is smaller than the cross-sectional area of the outer portion (55). The structure can reduce the pressing force required for pressing, while providing fast rebound and ensuring complete return. Also provided is a press pump comprising the plastic elastic reset mechanism.

Description

A plastic elastic reset mechanism and a press pump including the same. Technical Field

[0001] This application relates to a product dispensing device for dispensing liquid or semi-liquid products from a container, the product dispensing device being, in particular, an all-plastic press pump, and specifically relates to improvements to the plastic resilient reset mechanism of the press pump. Background Technology

[0002] Pump dispensers are widely used in the packaging of liquid or semi-liquid products in industries such as daily chemicals, food, and pharmaceuticals. With increasingly stringent environmental regulations, higher environmental standards are being imposed on product packaging. These packaging materials must meet at least one of the following requirements: reusability, recyclability, and biodegradability. Among these packages, the pump dispenser is the most difficult to recycle because it contains a metal spring that returns the pump to its ready-to-use position after product dispensing. However, the presence of the metal spring necessitates its removal during pump recycling, which increases the difficulty of recovery.

[0003] To meet environmental protection requirements, some companies have begun to experiment with producing all-plastic pumps, using plastic elastic return mechanisms (plastic springs) to replace metal springs. This allows all components of the pump to be made of plastic, making the entire pump easily recyclable. However, the technology of existing all-plastic pumps is still immature, mainly because the elastic force of the plastic elastic return mechanism is insufficient for the required operation. Specifically, the pressing force required to pump the product is greater than that of a metal spring, while the rebound force of the elastic return mechanism is less after the pressing force is removed. Therefore, existing all-plastic pumps suffer from problems such as a heavy pressing feel, slow return, and even incomplete rebound.

[0004] Therefore, in the field of all-plastic push pumps, there is a need to further improve the structure of the elastic reset mechanism in push pumps in order to solve the problems of high pressing force and rebound in existing push pumps mentioned above. Summary of the Invention

[0005] This application was made to address the problems existing in the prior art described above. The purpose of this application is to provide an improved plastic elastic reset mechanism for all-plastic push pumps, which can be deformed under less pressure and has better rebound force.

[0006] This application provides a plastic elastic reset mechanism for use in a press pump. The mechanism includes at least one elastic strip, which has an interface dividing it into an inner portion and an outer portion. When the elastic strip is compressed and deformed, the inner portion experiences compressive force, while the outer portion experiences tensile force. The force at the interface is zero. The elastic strip is configured such that, in the same cross-section, the cross-sectional area of ​​the inner portion is smaller than that of the outer portion.

[0007] When the plastic elastic reset mechanism is deformed under pressure, the inner portion experiences compressive force, which is the main force contributing to the heavy feel of pressing down, while the outer portion experiences tensile force, which helps generate the rebound force required for reset. Therefore, by making the cross-sectional area of ​​one side of the inner portion smaller than that of one side of the outer portion, it helps to reduce the compressive force generated in the plastic elastic reset mechanism when pressing down, thereby reducing the required pressing force. On the other hand, increasing the cross-sectional area of ​​the outer portion helps to generate the rebound force required for recovery. In this way, the structure of the plastic elastic reset mechanism reduces the pressing force required, while also ensuring rapid and complete recovery.

[0008] Preferably, the cross-sectional area of ​​the middle part of the elastic strip is the largest, and the cross-sectional area of ​​the elastic strip decreases along the direction towards both ends of the elastic strip.

[0009] In this way, the elastic strip is formed into a shape that is wide in the middle and narrow at both ends. This makes the elastic strip more flexible and reduces the pressure generated by the elastic strip during the pressing process, thereby improving the problem of the user's hand feeling heavy.

[0010] In one exemplary structure, in the relaxed state, the elastic strip is bow-shaped when viewed from the front. Alternatively, in the relaxed state, the elastic strip is bow-shaped when viewed from the side.

[0011] Preferably, the elastic reset mechanism includes at least one connecting ring and a plurality of elastic strips, wherein one end of each elastic strip is connected to the connecting ring, thereby connecting the plurality of elastic strips together via the connecting ring. For example, it may include upper and lower connecting rings, with the upper ends of the plurality of elastic strips connected to the upper connecting ring and the lower ends connected to the lower connecting ring.

[0012] Preferably, the elastic strip has a groove, and at least one connecting rib is provided in the groove, extending from the inner boundary of the groove to the outer boundary of the groove. The inner boundary of the groove is located near or within the inner portion, and the outer boundary is located near or within the outer portion. This structure of the groove and connecting rib further helps to reduce the compressive stress generated when the plastic elastic reset mechanism is compressed, increasing the resilience.

[0013] Preferably, multiple connecting ribs are provided in the groove.

[0014] The shape of the cross-section of the elastic strip can be set according to actual needs. For example, the cross-sectional shape of the elastic strip can be selected from the following shapes: circle, ellipse, rectangle, polygon, or a combination of at least two of these shapes.

[0015] This application also relates to a push pump, which includes a movable part and a fixed part, wherein the push pump includes the above-mentioned plastic elastic reset mechanism, one end of which is supported on the movable part and the other end of which is supported on the fixed part.

[0016] In a further specific structure, the movable part includes a pressure head and a piston rod connected to the lower part of the pressure head, and the fixed part includes a toothed sleeve and a cylinder fixedly connected together. A piston is provided at the lower end of the piston rod and extends into the cylinder, with the piston sealingly engaging with the inner wall of the cylinder. One end of the elastic reset mechanism is supported on the pressure head or piston rod, and the other end is supported on the toothed sleeve or cylinder. Attached Figure Description

[0017] The accompanying drawings illustrate a non-limiting preferred embodiment of this application, and the features and advantages of this application become more apparent when viewed in conjunction with the drawings. Wherein:

[0018] Figure 1 shows a schematic cross-sectional view of the press pump of this application.

[0019] Figure 2a shows a perspective view of the elastic reset mechanism of the first embodiment of the push pump of Figure 1.

[0020] Figure 2b shows a front view of the elastic reset mechanism of Figure 2a.

[0021] Figure 2c shows a side view of the elastic reset mechanism as seen along the direction indicated by arrow B in Figure 2b.

[0022] Figures 3-12 show various exemplary cross-sectional shapes of the elastic bar of the elastic reset mechanism obtained along line AA in Figure 2c.

[0023] Figure 13a shows a perspective view of the elastic bar of the elastic reset mechanism according to the second embodiment of this application.

[0024] Figure 13b shows a cross-sectional view of the elastic strip obtained along line CC in Figure 13a.

[0025] (Symbol Explanation) 1 Press Pump 10 Press Head 20 Tooth Cuff 30 Cylinder 40 Piston Rod 41 Piston 50 Elastic Reset Mechanism 51 Elastic Strip 52 Connecting Ring 53 Limiting Part 54 Inner Part 55 Outer Part 56 Groove 57 Connecting Rib L Boundary Line Detailed Implementation

[0026] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be understood that the embodiments shown in the drawings are merely preferred embodiments of the present invention and do not constitute a limitation on the scope of the present invention. Those skilled in the art can make various obvious modifications, variations, and equivalent substitutions to the present invention based on the embodiments shown in the drawings. Furthermore, without contradiction, the technical features in the different embodiments described below can be arbitrarily combined with each other, all of which fall within the protection scope of the present invention.

[0027] <First Embodiment>

[0028] Figure 1 illustrates an exemplary structure of the press pump 1 and its elastic reset mechanism 50 according to the first embodiment of this application, as well as various variations of the elastic reset mechanism 50.

[0029] Figure 1 is a cross-sectional view showing a schematic structure of the press pump 1 of this application. The press pump 1 includes a press head 10, a toothed sleeve 20, and a cylinder 30. The toothed sleeve 20 is fixedly connected to the cylinder 30. A piston rod 40 is connected to the lower part of the press head 10, wherein the upper end of the piston rod 40 is connected to the press head 10, and a piston 41 is provided on the lower end of the piston rod 40 and extends into the interior of the cylinder 30. A sealing fit is formed between the outer ring of the piston 41 and the inner surface of the cylinder 30.

[0030] The pressure head 10 and piston rod 40 are the moving parts of the press pump 1, while the toothed sleeve 20 and cylinder 30 are the fixed parts of the press pump 1. The pressure head 10 and piston rod 40 can reciprocate in the up-down direction relative to the toothed sleeve 20 and cylinder 30. As the pressure head 10 and piston rod 40 reciprocate relative to the toothed sleeve 20 and cylinder 30, the product contained in the cylinder 30 can be dispensed through the interconnected channel in the piston rod 40 and the nozzle of the pressure head 10.

[0031] The press pump 1 also includes a resilient reset mechanism 50, which is supported between the movable and fixed parts of the press pump 1. For example, the upper end of the resilient reset mechanism 50 is supported on the press head 10 or piston rod 40, and the lower end of the resilient reset mechanism 50 is supported on the toothed sleeve 20 or cylinder 30. When the user removes the pressing force applied to the press head 10 after the product has been pumped, the resilient reset mechanism 50 can cause the press head 10 and piston rod 40 to move upward and return to their standby position for the next pumping.

[0032] In this application, the elastic reset mechanism 50 is made of plastic, and therefore is a plastic elastic reset mechanism. The elastic reset mechanism 50 includes at least one, and preferably multiple, elastic strips 51. When the pressure head 10 is pressed down, the elastic strip 51 deforms under pressure, for example, by bending and increasing its curvature. During this process, a rebound force accumulates in the elastic strip 51, and when the user removes the pressing force, the rebound force in the elastic strip 51 causes the pressure head 10 and the piston rod 40 to spring back upward.

[0033] Figures 2a-2c show a perspective view, a front view, and a side view of the elastic reset mechanism 50, respectively, with the elastic reset mechanism 50 in its unloaded state. Preferably, in the unloaded state, the elastic reset mechanism 50 appears arc-shaped when viewed from the front, as shown in Figure 2b. More preferably, as shown in Figure 2c, the elastic reset mechanism 50 also appears arc-shaped when viewed from the side.

[0034] In the exemplary structure shown in the figure, the elastic reset mechanism 50 is a double-layer spring structure, which includes a first set of elastic strips 51 located at the top and a second set of elastic strips 51 located at the bottom. The elastic reset mechanism 50 preferably also includes a plurality of connecting rings 52, the ends of each elastic strip 51 being connected to the connecting rings 52, thereby enabling the elastic strips 51 to be connected together.

[0035] Of course, the elastic reset mechanism 50 in the press pump 1 of this application can also be a single-layer spring structure. Furthermore, the connecting ring 52 is also an optional structure, and the two ends of the elastic strip 51 can be directly supported or connected to the moving part and the fixed part of the press pump 1, respectively.

[0036] Preferably, the elastic reset mechanism 50 may further include a limiting portion 53, which limits the degree of deformation of the elastic strip 51 when the elastic reset mechanism 50 is pressed. In the exemplary structure shown in the figure, the limiting portion 53 is an elongated rod extending from the connecting ring 52, one end of which is connected to the connecting ring 52, and the other end is a free end. As the elastic reset mechanism 50 is compressed and deformed, the distance between the two connecting rings 52 at both ends of the elastic strip 51 decreases until the free end of the limiting portion 53 contacts the connecting ring 52 opposite to it, at which point further deformation of the elastic reset mechanism 50 is prevented.

[0037] The applicant analyzed the stress state of the elastic strip 51 when it is deformed under pressure. When the elastic reset mechanism 50 is pressed, one side of the arc-shaped elastic strip 51 will be subjected to tensile force, while the opposite side will be subjected to compressive force.

[0038] Here, the side of the elastic strip 51 subjected to tensile force is called the outer side, and the side of the elastic strip 51 subjected to compressive force is called the inner side. Referring to the cross-section of the elastic strip 51 shown in Figure 3 to analyze the force situation of the elastic strip 51, it can be seen that the outermost side of the elastic strip 51 is subjected to the greatest tensile force, and this tensile force gradually decreases in the direction towards the inward until it becomes zero. Subsequently, in the direction of continuing inward, the force on the elastic strip 51 becomes compressive force, and this compressive force gradually increases inward. At the innermost side of the elastic strip 51, this compressive force is the greatest.

[0039] Therefore, from the cross-section of the elastic strip 51, there exists a dividing line L within the elastic strip 51, as schematically represented by the dashed line in Figure 3. At this dividing line L, the force acting on the elastic strip 51 is zero, or in other words, the deformation of the elastic strip 51 at this dividing line L is zero. The interface formed by the dividing line L of the continuous cross-section of the elastic strip 51 divides the elastic strip 51 into two parts, namely the inner part 54 and the outer part 55. When the elastic strip 51 is deformed under pressure, the inner part 54 is subjected to compressive force, and the outer part 55 is subjected to tensile force.

[0040] Corresponding to different applied forces, different types of reaction forces are generated in the inner portion 54 and the outer portion 55. A compressive force is generated in the inner portion 54 of the elastic strip 51, which makes the user feel a heavy pressure during pressing. In the outer portion 55, a restoring force is generated corresponding to the tensile force. This restoring force allows the elastic reset mechanism 50 to return to its initial state after the pressing force is removed, thereby helping the pressure head 10 and piston rod 40 to spring back into place.

[0041] In this application, the dividing line L in the cross-section of the elastic strip 51 is set such that, within the same cross-section, the cross-sectional area of ​​the inner portion 54 is smaller than that of the outer portion 55, as shown in Figure 3. This smaller cross-sectional area of ​​the inner portion 54 means a relatively smaller volume of plastic material in the inner portion 54. This reduces the resistance generated in the inner portion 54 during the pressing of the elastic reset mechanism 50, making the pressure feel less heavy when pressed. Conversely, the larger cross-sectional area of ​​the outer portion 55 results in a greater rebound force due to stretching, which helps the pressure head 10 and piston rod 40 return to their positions after the pressing pressure is removed.

[0042] The position of the dividing line L in the cross section of the elastic strip 51 can be set in a variety of ways, such as by appropriately selecting the shape of the cross section of the elastic strip 51, by setting the curvature of the arc-shaped elastic strip 51 in the unloaded state, by setting the connection points between the two ends of the elastic strip 51 and the connecting ring 52, etc.

[0043] In the schematic structure shown in the figure, the elastic strip 51 is configured such that its cross-sectional area is largest in the middle longitudinal section and decreases towards both ends. In other words, the elastic strip 51 is formed into a shape that is wider in the middle and narrower at both ends. This structure makes the elastic strip 51 more easily deformable, thereby reducing the pressure exerted by the elastic strip 51 during pressing and thus improving the problem of a heavy feel for the user.

[0044] Furthermore, the cross-sectional shape of the elastic strip 51 can be selected from a variety of different geometries, such as rectangular, elliptical, circular, I-shaped, or a combination of two or more shapes. Figure 3-12 shows a variety of exemplary cross-sectional shapes of the elastic strip 51.

[0045] <Second Embodiment>

[0046] Figures 13a-13b illustrate an exemplary structure of the elastic strip 51 of the elastic reset mechanism 50 in the second embodiment of this application. In the second embodiment, the structure of other parts of the press pump 1 can be the same as that of the first embodiment, and will not be described in detail here.

[0047] Figures 13a-13b show an alternative construction of the elastic strip 51 of the elastic reset mechanism 50. In the elastic strip 51 shown in Figures 13a-13b, a groove 56 is provided in the outer portion 55 of the elastic strip 51. For example, this groove 56 can pass through the elastic strip 51 to form a through slot. At least one, preferably multiple, connecting ribs 57 are provided in the groove 56, extending from the inner boundary of the groove 56 to the outer boundary of the groove 56. The inner boundary of the groove 56 refers to the boundary of the groove 56 near the inner portion 54 of the elastic strip 51 or located on one side of the inner portion 54, and the outer boundary of the groove 56 refers to the boundary of the groove 56 near the outer portion 55 of the elastic strip 51 or located on one side of the outer portion 55. Thus, the elastic strip 51 of Figures 13a-13b forms a hollow structure. This hollow structure of the elastic strip 51 helps to increase the rebound force generated by the elastic strip 51 when it undergoes bending deformation.

[0048] On the other hand, the aforementioned groove 56 and connecting rib 57 structure can also be formed in the inner portion 54 of the elastic strip 51, that is, the inner portion 54 is formed as a hollow structure, which helps to reduce the pressure generated in the inner portion 54 when it is pressed and deformed.

[0049] The exemplary structure of the press pump of this application has been described in detail above. Those skilled in the art will recognize that various obvious modifications, variations, and recombinations can be made based on the above disclosure, and these are all within the scope of this application.

Claims

1. A plastic elastic reset mechanism for use in a press pump, the plastic elastic reset mechanism comprising at least one elastic strip, the elastic strip comprising an interface dividing the elastic strip into an inner portion and an outer portion, wherein, When the elastic strip is compressed and deformed, the inner portion experiences compressive force, the outer portion experiences tensile force, and the force on the elastic strip at the interface is zero. The elastic strip is characterized in that, in the same cross-section of the elastic strip, the cross-sectional area of ​​the inner portion is smaller than the cross-sectional area of ​​the outer portion.

2. The plastic elastic reset mechanism as described in claim 1, characterized in that, The cross-sectional area of ​​the elastic strip is the largest in the middle portion, and decreases along the direction towards both ends of the elastic strip.

3. The plastic elastic reset mechanism as described in claim 1, characterized in that, In the relaxed state, when viewed from the front, the elastic strip is arc-shaped; and / or In the relaxed state, when viewed from the side, the elastic strip is bow-shaped.

4. The plastic elastic reset mechanism as described in claim 1, characterized in that, The elastic reset mechanism includes at least one connecting ring and a plurality of elastic strips, wherein one end of each elastic strip is connected to the connecting ring, thereby connecting the plurality of elastic strips together through the connecting ring.

5. The plastic elastic reset mechanism as described in claim 1, characterized in that, The elastic strip has a groove, and at least one connecting rib is provided in the groove. The connecting rib extends from the inner boundary of the groove to the outer boundary of the groove. The inner boundary of the groove is close to or located in the inner portion, and the outer boundary of the groove is close to or located in the outer portion.

6. The plastic elastic reset mechanism as described in claim 5, characterized in that, Multiple connecting ribs are provided in the groove.

7. The plastic elastic reset mechanism as described in claim 1, characterized in that, The cross-sectional shape of the elastic strip is selected from the following shapes: circular, elliptical, rectangular, polygonal, or a combination of at least two of these shapes.

8. A push-button pump, the push-button pump comprising a movable part and a fixed part, characterized in that, The press pump includes a plastic elastic reset mechanism as described in any one of claims 1-7, one end of which is supported on the movable part and the other end of which is supported on the fixed part.

9. The push pump as described in claim 8, characterized in that, The movable part includes a pressure head and a piston rod connected to the lower part of the pressure head. The fixed part includes a toothed sleeve and a cylinder fixedly connected together. A piston is provided at the lower end of the piston rod and extends into the cylinder. The piston is in a sealing fit with the inner wall of the cylinder. One end of the plastic elastic reset mechanism is supported on the pressure head or the piston rod, and the other end of the plastic elastic reset mechanism is supported on the dental brace or the cylinder.

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