Down lock all-plastic pressing pump

Abstract

A down lock all-plastic pressing pump, comprising a movable part and a fixed part, wherein the movable part comprises a pressing head and a piston rod arranged below the pressing head, the fixed part comprises a threaded sleeve and an air cylinder, and an elastic reset mechanism is sleeved on the piston rod. The down lock all-plastic pressing pump further comprises a switching mechanism. The switching mechanism is arranged to enable relative axial displacement between the upper end of the elastic reset mechanism and the movable part or between the lower end and the fixed part when the down lock state of the down lock all-plastic pressing pump is released. The structure of the down lock all-plastic pressing pump is capable of realizing down locking, thereby reducing the risk of damage and leakage of the pressing pump, and preventing the elastic reset mechanism from yielding and deforming due to long-term pressure.

Description

Lower lock all-plastic push pump Technical Field

[0001] The present application relates to the field of product packaging, and in particular to a press pump for dispensing a product from a container containing the product. Background Art

[0002] Compression pumps are widely used in daily chemical, pharmaceutical, food and other industries. Compression pumps are installed on containers containing liquid or semi-liquid products and are used to pump products out of the containers for consumers to use.

[0003] To meet environmental protection requirements, the market is increasingly adopting all-plastic pumps, whose elastic reset mechanisms are also made of plastic. Most existing all-plastic pumps use upper-locking head pumps because their structure is relatively simple and easy to manufacture. Furthermore, in the case of upper-locking head pumps, when the head is locked, the plastic elastic reset mechanism remains relaxed, preventing the elastic reset mechanism from yielding and deforming due to prolonged pressure, which could cause the pump to fail.

[0004] However, during use, the upper lock pump exhibited some issues. First, during transportation, storage, and sales, the upper lock pump was relatively tall when in the upper lock position. This required a larger storage space, particularly a higher space, during transportation, and taller shelves for storage and sales. All of these factors increased transportation and sales costs.

[0005] Secondly, top-lock pumps offer poor drop and impact resistance. Their high height makes them susceptible to breakage and leakage when dropped or impacted. Furthermore, to prevent the pump from accidentally being pressed and causing product leakage, a clip is required, which further increases the pump's manufacturing cost.

[0006] Furthermore, in pumps using a plastic elastic return mechanism, to increase the elastic force of the elastic return mechanism, the plastic elastic return mechanism is placed outside the cylinder, surrounding the cylinder, thereby providing a larger deformation space for the elastic return mechanism and providing sufficient elastic force. However, this external elastic return mechanism is easily damaged during the filling process.

[0007] Therefore, there is a need in this field to further improve the structure of the press pump to realize a fully plastic press pump for the lower lock head, overcome the technical problems existing in the above-mentioned prior art, and at the same time retain the beneficial structure of the upper lock head press pump. Summary of the Invention

[0008] This application is made to solve the problems existing in the above-mentioned prior art. The purpose of this application is to provide a lower lock head all-plastic press pump to overcome the technical problems existing in the existing upper press pump, that is, it is not easy to break and occupies less space.

[0009] The present application provides a lower lock all-plastic press pump, which includes a movable portion and a fixed portion, wherein the movable portion includes a pressure head and a piston rod disposed below the pressure head, and the fixed portion includes a threaded sleeve and a cylinder, the threaded sleeve and the cylinder being fixedly connected together. An elastic reset mechanism is sleeved on the piston rod, and the elastic reset mechanism is made of plastic. The upper end of the elastic reset mechanism is supported on the movable portion, and the lower end of the elastic reset mechanism is supported on the fixed portion. In the present application, the lower lock all-plastic press pump also includes a switching mechanism. The switching mechanism is disposed between the movable portion and the upper end of the elastic reset mechanism and is configured to cause relative axial displacement between the upper end of the elastic reset mechanism and the movable portion when the lower lock state of the lower lock all-plastic press pump is released. Alternatively, the switching mechanism is disposed between the fixed portion and the lower end of the elastic reset mechanism and is configured to cause relative axial displacement between the lower end of the elastic reset mechanism and the fixed portion when the lower lock state of the lower lock all-plastic press pump is released.

[0010] In the aforementioned all-plastic push-pump with a lower lock, a switching mechanism allows the upper end of the elastic return mechanism to move relative to the movable portion, or the lower end to move relative to the fixed portion, during the process of setting the push-pump to the lower lock state and releasing the lower lock. This prevents the elastic return mechanism from being compressed and deformed over time due to the lower lock. This achieves an all-plastic push-pump with a lower lock, reducing the risk of damage and leakage.

[0011] In an exemplary embodiment, an upper supporting portion is provided at the upper end of the elastic reset mechanism, and the switching mechanism includes a first matching portion formed on the upper supporting portion and a second matching portion formed on the piston rod.

[0012] Preferably, a rotation-stopping mechanism is provided between the elastic reset mechanism and the cylinder, and the rotation-stopping mechanism is configured to prevent the elastic reset mechanism from rotating together with the piston rod.

[0013] Specifically, the structure of the switching mechanism can be set as follows: the first matching part is a first groove formed on the inner surface of the upper support part, and the second matching part is a spiral flange formed on the outer surface of the piston rod, and the first groove can match with the spiral flange.

[0014] Alternatively, the structure of the switching mechanism can also be configured as follows: the first matching portion is a recess formed on the inner surface of the upper support portion, and the second matching portion is a convex strip formed on the outer surface of the piston rod and extending in the axial direction.

[0015] The structure of the switching mechanism can also be set as follows: the first matching part is a reduced diameter part formed in the upper support part, and the second matching part is a retaining ring formed on the outer surface of the piston rod, the minimum inner diameter of the reduced diameter part is smaller than the maximum outer diameter of the retaining ring, and the upper surface of the retaining ring is formed as a slope that gradually decreases in the upward direction, so that the retaining ring can move upward over the reduced diameter part, but prevents the retaining ring from moving downward over the reduced diameter part.

[0016] In another example, the structure of the switching mechanism can be set as follows: the first matching portion is a spiral groove formed in the upper support portion, and the second matching portion is a protrusion formed on the outer surface of the piston rod, and the protrusion can be matched in the spiral groove.

[0017] A specific structure of the anti-rotation mechanism includes a slot formed on the inner wall of the cylinder and a guide block formed on the elastic return mechanism, wherein the guide block can be fitted into the slot.

[0018] In another exemplary embodiment, a lower support portion is provided at the lower end of the elastic reset mechanism, and the switching mechanism is provided between the lower support portion and the cylinder.

[0019] Specifically, the all-plastic lower lock pump also includes a cylinder plug, which is supported on a stepped portion within the cylinder. The lower support portion is relatively rotatably sleeved within the cylinder plug. The switching mechanism includes a spiral flange formed on one of the outer surface of the lower support portion and the inner surface of the cylinder plug, and a spiral groove formed on the other of the outer surface of the lower support portion and the inner surface of the cylinder plug, which is capable of cooperating with the spiral flange.

[0020] Preferably, a synchronous rotation mechanism is also provided between the piston rod and the elastic reset mechanism, so that the piston rod can rotate together with the elastic reset mechanism, wherein the synchronous rotation mechanism includes: a stop ridge provided on one of the piston rod and the elastic reset mechanism; and a second groove provided on the other of the piston rod and the elastic reset mechanism.

[0021] In the present application, the elastic reset mechanism is at least partially disposed within the cylinder. This prevents damage to the elastic reset mechanism during the filling process. Furthermore, the press pump can be conveniently removed from and inserted into the container during refilling.

[0022] Furthermore, in order to increase the elastic force of the elastic reset mechanism, the elastic reset mechanism preferably adopts a multi-layer structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings illustrate non-limiting preferred embodiments of the present invention, which, when combined with the accompanying drawings, make the features and advantages of the present invention more apparent.

[0024] FIG1 shows a cross-sectional view of a press pump according to a first embodiment of the present application, wherein the press pump is shown in a lower locking state.

[0025] FIG2 shows another cross-sectional view of the press pump of FIG1 , schematically illustrating the operation of the press pump to release the lower locking state thereof.

[0026] FIG3 shows another cross-sectional view of the compression pump of FIG1 , wherein the compression pump has been released from the lower locking state and is in its upper standby state.

[0027] FIG. 4 shows a perspective view of the piston rod of the compression pump of FIG. 1 .

[0028] FIG. 5 is a perspective view showing the elastic return mechanism of the pressing pump of FIG. 1 .

[0029] FIG6 shows a three-dimensional view of the piston rod of FIG4 and the elastic reset mechanism of FIG5 assembled together, wherein the pressing pump is in a lower locking state.

[0030] FIG7 shows another perspective view of the piston rod of FIG4 and the elastic reset mechanism of FIG5 assembled together, wherein the pressing pump is in an upper standby state.

[0031] FIG8 shows a cross-sectional view of the pressing pump according to the second embodiment of the present application, in which the pressing pump is shown in a lower locking state.

[0032] FIG. 9 shows another cross-sectional view of the press pump of FIG. 8 , schematically illustrating the operation of the press pump to release the lower locking state thereof.

[0033] FIG. 10 shows another cross-sectional view of the compression pump of FIG. 8 , wherein the compression pump has been released from the lower locking state and is in its upper standby state.

[0034] FIG. 11 is a perspective view showing the piston rod and the elastic reset mechanism in the pressing pump of FIG. 8 assembled together.

[0035] FIG. 12 shows an exploded view of the piston rod and the elastic return mechanism of FIG. 11 .

[0036] FIG13 shows a cross-sectional view of the pressing pump according to the third embodiment of the present application, in which the pressing pump is shown in a lower locking state.

[0037] FIG. 14 shows another cross-sectional view of the compression pump of FIG. 13 , wherein the compression pump has been released from the lower locking state and is in its upper standby state.

[0038] FIG. 15 is a perspective view showing an upper support portion of the elastic return mechanism of the pressing pump of FIG. 13 .

[0039] FIG. 16 shows a perspective view of the piston rod of the compression pump of FIG. 13 .

[0040] FIG17 shows a three-dimensional view of the upper support portion of FIG15 and the piston rod of FIG16 assembled together, wherein the pressing pump is in a lower locking state.

[0041] FIG. 18 shows another perspective view of the upper support portion of FIG. 15 and the piston rod of FIG. 16 assembled together, wherein the compression pump is in an upper standby state.

[0042] FIG19 shows a cross-sectional view of the pressing pump according to the fourth embodiment of the present application, in which the pressing pump is shown in a lower locking state.

[0043] FIG. 20 shows another cross-sectional view of the compression pump of FIG. 19 , wherein the compression pump has been released from the lower locking state and is in its upper standby state.

[0044] FIG21 is a partially enlarged view of portion I in FIG20.

[0045] FIG22 shows a cross-sectional view of the pressing pump according to the fifth embodiment of the present application, in which the pressing pump is shown in a lower locking state.

[0046] FIG. 23 shows another cross-sectional view of the compression pump of FIG. 22 , wherein the compression pump has been released from the lower locking state and is in its upper standby state.

[0047] FIG. 24 is a cross-sectional view of the upper support portion of the elastic return mechanism of the pressing pump of FIG. 22 .

[0048] FIG. 25 shows a cross-sectional view of the piston rod of the compression pump of FIG. 22 .

[0049] FIG. 26 shows a front view of the piston rod of FIG. 25 .

[0050] 27a to 27d show alternative structures of the elastic return mechanism that can be used in the compression pump of the present application.

[0051] (Explanation of Symbols)

[0052] 100 pumps

[0053] 110 pressure head

[0054] 120 braces

[0055] 130 cylinder

[0056] 131 ridges

[0057] 132 Cylinder plug

[0058] 133 Steps

[0059] 140 piston rod

[0060] 141 spiral flange

[0061] 142 Piston

[0062] 150 elastic reset mechanism

[0063] 151 upper support

[0064] 152 Lower Circle

[0065] 153 Center Circle

[0066] 154 elastic strips

[0067] 155 First Groove

[0068] 156 guide block

[0069] 200 pumps

[0070] 210 pressure head

[0071] 220 braces

[0072] 230 cylinder

[0073] 232 cylinder plug

[0074] 233 spiral groove

[0075] 240 piston rod

[0076] 241 stop rib

[0077] 250 elastic reset mechanism

[0078] 251 Upper Circle

[0079] 252 lower support

[0080] 253 Center Circle

[0081] 254 Second Groove

[0082] 255 spiral flange

[0083] 300 pumps

[0084] 310 pressure head

[0085] 320 braces

[0086] 330 cylinder

[0087] 340 piston rod

[0088] 341 ridges

[0089] 350 elastic reset mechanism

[0090] 351 upper support

[0091] 352 Notch

[0092] 353 anti-rotation protrusion

[0093] 400 Press Pump

[0094] 410 pressure head

[0095] 420 braces

[0096] 430 cylinder

[0097] 440 piston rod

[0098] 441 clasp

[0099] 442 limiting convex ring

[0100] 450 elastic reset mechanism

[0101] 451 upper support

[0102] 452 reduced diameter part

[0103] 453 lower slope

[0104] 500 pumps

[0105] 510 pressure head

[0106] 520 braces

[0107] 530 cylinder

[0108] 540 piston rod

[0109] 541 Bump

[0110] 550 elastic reset mechanism

[0111] 551 upper support

[0112] 552 spiral groove DETAILED DESCRIPTION

[0113] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the drawings illustrate only preferred embodiments of the present invention and do not limit the scope of the present invention. Those skilled in the art may make various obvious modifications, variations, and equivalent substitutions to the present invention based on the embodiments shown in the drawings. Furthermore, the technical features of the different embodiments described below may be arbitrarily combined with each other, provided that no contradiction exists. All of these combinations fall within the scope of protection of the present invention.

[0114] In addition, the expressions related to directions such as "up" and "down" used in this article are based on the orientation of the press pump when in use. Those skilled in the art will know that in certain situations, such as during transportation, storage, etc., the orientation of the press pump may change.

[0115] <First embodiment>

[0116] Figures 1 to 8 illustrate a compression pump 100 according to a first embodiment of the present application. Compression pump 100 includes a compression head 110, a mouthpiece 120, and a cylinder 130. Mouthpiece 120 and cylinder 130 are fixedly connected. A piston rod 140 is connected or disposed below compression head 110 and extends into cylinder 130.

[0117] The compression pump 100 further includes an elastic return mechanism 150, which is disposed inside the cylinder 130 and sleeved on the piston rod 140. A piston 142 is disposed at the lower end of the piston rod 140.

[0118] A connection structure, such as internal and external threads, is provided between the pressure head 110 and the mouthpiece 120. Thus, during transportation or sales, the pressure head 110 and mouthpiece 120 can be connected together, thereby placing the compression pump 100 in a down-locked state, as shown in FIG1 . Therefore, the compression pump 100 of the present application is a down-locked type compression pump.

[0119] Figure 4 shows a perspective view of the elastic return mechanism 150 of the compression pump 100 shown in Figure 1 . As can be seen, the elastic return mechanism 150 is a multi-layer structure made of plastic, for example, the same plastic material as the other components of the compression pump 100. The elastic return mechanism 150 comprises an upper support portion 151, a lower ring 152, and a middle ring 153. At least one elastic strip 154, preferably two or more elastic strips 154, is disposed between the upper support portion 151 and the middle ring 153, and between the lower ring 152 and the middle ring 153, respectively.

[0120] Returning to Figure 1 , in the installed state, the upper support portion 151 of the elastic return mechanism 150 is supported on the piston rod 140. A cylinder plug 132 is provided at the bottom of the cylinder 130. The cylinder plug 132 engages with a step 133 formed at the bottom of the cylinder 130 and is positioned above the piston 142. The lower ring 152 of the elastic return mechanism 150 is supported on the cylinder plug 132.

[0121] Figure 5 shows a perspective view of the piston rod 140 in the compression pump 100 of Figure 1. A spiral flange 141 is formed on the outer surface of the piston rod 140. Correspondingly, a first groove 155 is formed on the upper support portion 151 of the elastic reset mechanism 150, and the first groove 155 can be matched with the spiral flange 141.

[0122] When the ram 110 is rotated to release the locking connection between the ram 110 and the dental brace 120, the piston rod 140 rotates along with the ram 110. At this time, the piston rod 140 moves upward relative to the upper support portion 151 through the interaction between the spiral flange 141 and the first groove 155, as shown in Figures 6 and 7.

[0123] A rotation-stop mechanism is provided between the cylinder 130 and the elastic return mechanism 150. The rotation-stop mechanism includes a protrusion 131 that fits into a slot on the inner wall of the cylinder 130. Furthermore, recesses are formed on the lower ring 152 and the middle ring 153 of the elastic return mechanism 150, as shown in Figures 6 and 7, which fit into the protrusion 131. Alternatively, the rotation-stop mechanism may include a guide block 156 provided on the elastic return mechanism 150. The guide block 156 may, for example, be formed on at least one of the lower ring 152 and the middle ring 153. For example, in Figure 5, guide blocks 156 are provided on both the lower ring 152 and the middle ring 153. The guide blocks 156 fit into slots on the inner wall of one of the rings. This structure prevents the elastic return mechanism 150 from rotating with the piston rod 140 and allows it to move only in the vertical direction.

[0124] In an alternative structure, the anti-rotation mechanism may include a narrow groove formed on the inner wall of the cylinder 130, which cooperates with the guide block 156 of the elastic return mechanism 150 to limit the movement mode of the elastic return mechanism 150.

[0125] Next, the operation of the pressing pump 100 will be described with reference to FIG. 2 and FIG. 3 .

[0126] As shown in FIG2 , to unlock the pressing head 110, the user rotates the pressing head 110 relative to the mouthpiece 120. During this process, the spiral flange 141 interacts with the first groove 155, causing the upper support portion 151 of the elastic reset mechanism 150 to move downward relative to the piston rod 140, causing the piston rod 140 to be compressed.

[0127] Then, as shown in FIG3 , when the connection between the pressure head 110 and the mouthpiece 120 is released, the pressure head 110 and the piston rod 140 are pushed upward to their top dead center under the action of the compressed piston rod 140. At this point, the compression pump 100 is in its standby state, and the user can pump the product out of the container by pressing the pressure head 110 of the compression pump 100 downward.

[0128] It can be seen that in the pressing pump 100 shown in the figure, when the pressing pump 100 is in its lower locking state, the elastic reset mechanism 150 therein can still be in a relaxed state, thereby preventing the elastic reset mechanism 150 from yielding and deforming due to long-term pressure.

[0129] <Second embodiment>

[0130] 8 to 13 show a second embodiment of the present application of the compression pump 200. Unless otherwise described or conflicting, the specific structure described above with respect to the first embodiment also applies to the second embodiment. The following will specifically describe the structure of the second embodiment that differs from the first embodiment.

[0131] As shown in Figure 8, the pressing pump 200 includes a pressing head 210, a toothed sleeve 220, and a cylinder 230. A piston rod 240 is provided below the pressing head 210, and an elastic reset mechanism 250 is sleeved on the piston rod 240. The pressing pump 200 is also a lower lock type pressing pump.

[0132] Figures 11 and 12 show the piston rod 240 and elastic reset mechanism 250 assembled and disassembled, respectively. The elastic reset mechanism 250 is a multi-layer structure comprising an upper ring 251, a lower support portion 252, and a middle ring 253. At least one, and preferably two or more, elastic strips are disposed between the upper ring 251 and the middle ring 253, and between the lower support portion 252 and the middle ring 253. Second grooves 254 are provided on the upper ring 251, the lower support portion 252, and the middle ring 253. These grooves 254 engage with longitudinally extending retaining ridges 241 on the piston rod 240, thereby securing the elastic reset mechanism 250 to the piston rod 240 in a non-rotatable manner. Therefore, when the ram 210 and piston rod 240 are rotated, the elastic reset mechanism 250 rotates with them.

[0133] In the installed state, the lower support portion 252 fits within the cylinder plug 232, as can be seen in FIG8 . A spiral flange 255 is formed on the outer surface of the lower support portion 252. Correspondingly, a spiral groove 233 is formed on the inner surface of the cylinder plug 232. The cylinder plug 232 is fixedly mounted within the cylinder 230. The spiral flange 255 and the spiral groove 233 cooperate with each other so that when the elastic return mechanism 250 rotates with the ram 210 and piston rod 240, the spiral flange 255 and the spiral groove 233 interact to cause the lower support portion 252 to move upward relative to the cylinder plug 232.

[0134] Referring to Figures 9 and 10 , to release the lock state of the compression pump 100, the user rotates the compression head 210, causing the piston rod 240 and the elastic return mechanism 250 to rotate together. This causes the elastic return mechanism 250 to rotate relative to the cylinder plug 232, thereby causing the lower support portion 252 of the elastic return mechanism 250 to move upward relative to the cylinder plug 232. This upward movement causes the elastic return mechanism 250 to be compressed, thereby accumulating elastic force within the elastic return mechanism 250. When the compression head 210 rotates to a position that releases the connection with the mouthpiece 220, the elastic force of the elastic return mechanism 250 pushes the compression head 210 and piston rod 240 upward to their top dead center. At this point, the compression pump 200 is in its standby state, and the user can pump the product from the container by pressing the compression head 210 downward.

[0135] <Third embodiment>

[0136] Figures 13 to 18 illustrate a compression pump 300 according to a third embodiment of the present invention. Unless otherwise specified or conflicting, the specific structures described above with respect to the first and second embodiments also apply to the third embodiment. The following details the differences between the third embodiment and the first and second embodiments.

[0137] As shown in FIG13 , the pressing pump 300 of the third embodiment is a lower lock type pressing pump, which includes a pressing head 310 , a toothed sleeve 320 and a cylinder 330 . The pressing head 310 is connected to a piston rod 340 , and an elastic reset mechanism 350 is sleeved on the piston rod 340 .

[0138] The elastic reset mechanism 350 includes an upper support portion 351. FIG15 shows a perspective view of the upper support portion 351, wherein a recess 352 is formed on the inner side of the upper support portion 351. FIG16 shows a perspective view of the piston rod 340, wherein a longitudinally extending ridge 341 is formed on the outer surface of the piston rod 340. The recess 352 in the upper support portion 351 matches the ridge 341 on the piston rod 340. When the recess 352 and the ridge 341 are aligned, the piston rod 340 can move in the vertical direction relative to the upper support portion 351, as schematically shown in FIG17 and FIG18. When the recess 352 and the ridge 341 are misaligned, the ridge 341 abuts against the rest of the upper support portion 351, preventing the piston rod 340 from moving up and down relative to the upper support portion 351.

[0139] Furthermore, a rotation-stopping protrusion 353 is formed on the upper support portion 351 , and the rotation-stopping protrusion 353 cooperates with a structure such as a groove or a protrusion in the cylinder 330 to prevent the upper support portion 351 from rotating together with the piston rod 340 .

[0140] When the pressing pump 300 is in the lower locking state, the pressing head 310 rotates relative to the mouthpiece 320 to a position where the recess 352 and the protrusion 341 are offset, and the upper end of the protrusion 341 abuts against the bottom of the upper support portion 351 .

[0141] To release the lower lock state of the compression pump 300, the user rotates the compression head 310, and the piston rod 340 rotates with the compression head 310 until the notch 352 is aligned with the protrusion 341. The user can then pull the compression head 310 and piston rod 340 upward. When the compression head 310 and piston rod 340 are pulled to their top dead center, the lower end of the protrusion 341 also moves above the upper support portion 351. The user then rotates the compression head 310 and piston rod 340 again, causing the protrusion 341 to be offset from the notch 352, and the lower end of the protrusion 341 will abut the top of the upper support portion 351. At this point, the compression pump 300 is in its upper standby state.

[0142] <Fourth embodiment>

[0143] Figures 19 to 21 illustrate a compression pump 400 according to a fourth embodiment of the present application. Unless otherwise specified or conflicting, the specific structures described above with respect to the first to third embodiments also apply to the fourth embodiment. The following details the structures of the fourth embodiment that differ from the first to third embodiments.

[0144] As shown in Figures 19 and 20, the pressing pump 400 of the fourth embodiment is a lower lock type pressing pump, which includes a pressing head 410, a brace 420 and a cylinder 430. The pressing head 410 is connected to a piston rod 440, and an elastic reset mechanism 450 is sleeved on the piston rod 440.

[0145] The elastic return mechanism 450 includes an upper support portion 451 disposed within the cylinder 430 .

[0146] Figure 21 shows a partial, enlarged view of section I in Figure 20 , which more clearly illustrates the structure of the upper support portion 451 and the portion of the piston rod 440 that cooperates with it. A reduced diameter portion 452 is formed in the upper support portion 451, and a corresponding snap ring 441 is formed on the piston rod 440. The maximum outer diameter of the snap ring is larger than the minimum inner diameter of the reduced diameter portion 452. Furthermore, it can be seen that the upper surface of the snap ring 441 is formed as an inclined surface that tapers upward. This inclined surface facilitates upward movement of the snap ring 441 over the upper support portion 451 when the piston rod 440 moves upward relative to the upper support portion 451. After the snap ring 441 moves upward over the reduced diameter portion 452, its lower surface abuts against the upper surface of the reduced diameter portion 452, preventing the piston rod 440 from moving downward relative to the upper support portion 451.

[0147] Preferably, a lower inclined surface 453 is formed on the lower side of the reduced diameter portion 452 , and the lower inclined surface 453 cooperates with the inclined surface on the upper surface of the snap ring 441 , thereby further facilitating the snap ring 441 to move upward and pass over the reduced diameter portion 452 .

[0148] Preferably, a limiting protruding ring 442 is further formed on the piston rod 440 , which can limit the top dead center position of the stroke of the pressure head 410 and the piston rod 440 .

[0149] Referring to Figures 19 and 20 , to release the locked state of the compression pump 400, the user pulls up on the compression head 410, causing the piston rod 440 to move upward relative to the upper support portion 451, and causing the snap ring 441 on the piston rod 440 to pass over the reduced diameter portion 452 of the upper support portion 451. When the compression head 410 and piston rod 440 move upward to their top dead center, the snap ring 441 abuts against the upper surface of the reduced diameter portion 452. Then, pressing down on the compression head 410 causes the reduced diameter portion 452 to move downward, thereby compressing the elastic return mechanism 450.

[0150] <Fifth embodiment>

[0151] Figures 22 to 26 illustrate a fifth embodiment of a compression pump 500 of the present application. Unless otherwise specified or conflicting, the specific structures described above with respect to the first to fourth embodiments also apply to the fifth embodiment. The following details the differences between the fifth embodiment and the first to fourth embodiments.

[0152] The pressing pump 500 is also a lower lock type pressing pump, which includes a pressing head 510, a brace 520 and a cylinder 530. The pressing head 510 is connected to a piston rod 540, and an elastic reset mechanism 550 is sleeved on the piston rod 540.

[0153] The elastic return mechanism 550 includes an upper support portion 551 disposed within the cylinder 530. As shown in FIG24 , a spiral groove 552 is formed on the inner surface of the elastic return mechanism 550. As can be seen in FIG25 and FIG26 , a bump 541 is formed on the piston rod 540, which engages with the spiral groove 552 in the upper support portion 551. Thus, as the piston rod 540 rotates, it can move upward relative to the upper support portion 551.

[0154] Returning to Figures 22 and 23, to unlock the pump 500, the user rotates the pump head 510 (see Figure 22), causing the piston rod 540 thereon to rotate. As the piston rod 540 rotates, the interaction between the protrusion 541 and the spiral groove 552 causes the piston rod 540 to move upward relative to the upper support portion 551, thereby moving to the upper standby position.

[0155] The above describes the preferred embodiments of the lower lock head all-plastic press pump of the present application. Those skilled in the art can make various obvious variations and modifications based on these embodiments.

[0156] For example, in addition to the two-layer elastic return mechanism shown, which includes an upper ring, a lower ring, and a middle ring, the elastic return mechanism can also take other forms, such as a three-layer or more-layer elastic return mechanism, and can also take elastic strips with other shapes besides the bow-shaped elastic strip. Figures 27a to 27d show some possible elastic return mechanisms.

[0157] For another example, in the structure shown in the figure, the upper support portion and the lower support portion are integrally formed on the elastic reset mechanism. Those skilled in the art will appreciate that the upper support portion and the lower support portion can also be formed separately and connected to the elastic reset mechanism.

[0158] In addition, the piston rod can be an integral part of the bottom of the ram, or can be formed separately and then connected to the ram. Moreover, the piston rod can also be a single piece, or can comprise multiple sections, and can be connected together to form a piston rod.

Claims

1. A fully plastic push pump with a lower lock head, the lower lock head push pump comprising a movable part and a fixed part, wherein, The movable part includes a ram head and a piston rod disposed below the ram head, and the fixed part includes a dental appliance sleeve and a cylinder. The dental appliance sleeve and the cylinder are fixedly connected together. An elastic reset mechanism is sleeved on the piston rod. The elastic reset mechanism is made of plastic. Wherein, the upper end of the elastic reset mechanism is supported on the movable part, and the lower end of the elastic reset mechanism is supported on the fixed part. It is characterized in that, The lower-lock full-plastic pressing pump further includes a switching mechanism. Wherein, the switching mechanism is disposed between the movable part and the upper end of the elastic reset mechanism, and is configured to be able to generate a relative axial displacement between the upper end of the elastic reset mechanism and the movable part when releasing the lower-lock state of the lower-lock full-plastic pressing pump; or The switching mechanism is disposed between the fixed part and the lower end of the elastic reset mechanism, and is configured to be able to generate a relative axial displacement between the lower end of the elastic reset mechanism and the fixed part when releasing the lower-lock state of the lower-lock full-plastic pressing pump.

2. The lower lock head all-plastic pressing pump according to claim 1, characterized in that An upper support portion is provided at the upper end of the elastic reset mechanism. The switching mechanism includes a first mating portion formed on the upper support portion and a second mating portion formed on the piston rod.

3. The lower lock full-plastic pressing pump according to claim 2, characterized in that An anti-rotation mechanism is provided between the elastic reset mechanism and the cylinder. The anti-rotation mechanism is configured to prevent the elastic reset mechanism from rotating together with the piston rod.

4. The lower lock full-plastic pressing pump according to claim 2 or 3, characterized in that, The first mating portion is a first groove formed on the inner surface of the upper support portion, and the second mating portion is a spiral flange formed on the outer surface of the piston rod. The first groove can be engaged with the spiral flange.

5. The lower lock full-plastic pressing pump according to claim 2 or 3, characterized in that, The first mating portion is a notch formed on the inner surface of the upper support portion, and the second mating portion is an axially extending rib formed on the outer surface of the piston rod.

6. The lower lock head all-plastic pressing pump according to claim 2 or 3, characterized in that, The first mating portion is a reduced-diameter portion formed in the upper support portion, and the second mating portion is a snap ring formed on the outer surface of the piston rod. The minimum inner diameter of the reduced-diameter portion is smaller than the maximum outer diameter of the snap ring, and the upper surface of the snap ring is formed as an inclined surface that tapers in the upward direction, so that the snap ring can move upward over the reduced-diameter portion, but prevents the snap ring from moving downward over the reduced-diameter portion.

7. The lower lock head all-plastic pressing pump according to claim 2 or 3, characterized in that The first mating portion is a spiral groove formed in the upper support portion, and the second mating portion is a protrusion formed on the outer surface of the piston rod. The protrusion can be fitted in the spiral groove.

8. The lower lock full-plastic pressing pump according to claim 3, wherein, The anti-rotation mechanism includes a slot formed on the inner wall of the cylinder and a guide block formed on the elastic reset mechanism. The guide block can be fitted in the slot.

9. The lower lock full-plastic pressing pump according to claim 1, characterized in that, A lower support portion is provided at the lower end of the elastic reset mechanism. The switching mechanism is disposed between the lower support portion and the cylinder.

10. The lower lock head all-plastic pressing pump according to claim 9, characterized in that, The lower-lock full-plastic pressing pump further includes a cylinder plug. The cylinder plug is supported on a stepped portion in the cylinder. The lower support portion is rotatably sleeved in the cylinder plug. And the switching mechanism includes: A spiral flange, the spiral flange being formed on one of the outer surface of the lower support portion and the inner surface of the cylinder plug, and A spiral groove, the spiral groove being formed on the other of the outer surface of the lower support portion and the inner surface of the cylinder plug and being capable of cooperating with the spiral flange.

11. The lower lock full-plastic pressing pump according to claim 10, characterized in that, A synchronous rotation mechanism is further provided between the piston rod and the elastic reset mechanism, such that the piston rod can drive the elastic reset mechanism to rotate together, wherein the synchronous rotation mechanism includes: a stop rib provided on one of the piston rod and the elastic reset mechanism; and a second groove provided on the other of the piston rod and the elastic reset mechanism.

12. The lower lock full-plastic pressing pump according to claim 1, wherein The elastic reset mechanism is at least partially disposed within the cylinder.

13. The lower lock full-plastic pressing pump according to claim 1, characterized in that, The elastic reset mechanism is an elastic reset mechanism with a multi-layer structure.

Images