Portable vacuum pump with protection against suction of liquids

Abstract

A portable vacuum pump with protection against liquid aspiration is provided with at least two sensors for detecting liquid at the inlet of the pump's air suction channel, and the sensors are connected to the pump's controller, which is configured to terminate pumping (vacuum drawing) when liquid is detected by the sensors. The two sensors are positioned at a distance appropriate to receive at least a drop of liquid. Because the liquid is conductive, a circuit between the sensors and the electronics is closed, thus signaling the electronics to stop pump operation and thereby terminating air aspiration. Alternatively, a single liquid sensor is used, molded as a metal element installed in a groove in the housing below the plastic plate, through which the conductivity of the possible liquid is detected. Upon detection, the metal element communicates with a PCBA, which is configured to terminate air aspiration.

Description

[Technical Field]

[0001] The present invention belongs to the field of household appliances, in particular to the field of devices and methods for storing food in a vacuum. More precisely, it belongs to the field of vacuum pumps for generating negative pressure in vacuum containers, vacuum bags and containers with universal vacuum lids. The present invention relates to a portable vacuum pump with protection against the suction of liquids. [Background technology]

[0002] Storing food in a vacuum is known to be the most natural method of storage, as it does not use preservatives to extend the shelf life of food. Vacuum containers and similar systems are well known on the market, and in the last few years, vacuuming has become increasingly common using portable electric pumps, which are useful and fast in the process of creating a vacuum inside food containers.

[0003] A problem with transportable vacuum pumps is that they can suck up liquids, which can interfere with the operation of the complex system of suction valves and therefore render the pump partially or completely useless. This problem is even more pronounced when viscous liquids, oils, marinades, etc. are being sucked in. Because vacuum pumps are not only used with vacuum containers, but also with bags, the problem of liquid suction is even more evident, as even small amounts of liquid present in the bag can enter the pump and impair its operation.

[0004] It is therefore an object of the present invention to construct a portable vacuum pump that is capable of preventing the suction of liquids from any kind of storage container, bag or other vessel, and the construction should also allow for easy and efficient cleaning while allowing the entire device to remain portable and compact in design.

[0005] Prior art Several different vacuum pumps are known, some of which are autonomous and some of which are installed in complex systems such as laboratory vacuum drawers and professional vacuum machines. These systems are specifically adapted to prevent the aspiration of liquids, but are not useful for everyday and domestic use. They therefore differ in construction and operation from the present invention.

[0006] WO 2018 / 147813 discloses a device for vacuum sealing glass and plastic containers with lids for storing food, comprising a flexible valve and a hand vacuum pump with an integrated dagger for piercing the metal or plastic lid of the container. The latter has a housing, inside which a movable part is located with a handle having an integrated dagger for piercing the metal or plastic lid of the container. The movable part has space inside to accommodate a larger number of said valves. This solution does not prevent the suction of liquid, making it susceptible to malfunction due to the suctioned liquid.

[0007] Some solutions prevent liquid from entering the vacuum pump by using a mechanical barrier. For example, Chinese Utility Model No. 209284904 discloses a vacuum extraction device including a vacuum pump, an air suction port, and an air outlet, and a waterproof, breathable membrane is disposed at the extraction opening to prevent liquid from being pumped into the vacuum pump. Similarly, Chinese Utility Model No. 212638057 discloses a gas-liquid separation device for food vacuum packaging equipment including a water separation mechanism.

[0008] WO 2008 / 112093 describes a vacuum food storage device having a container, a lid, a pump for evacuating air, and a switch engageable by contact of the pump with the lid to allow the pump to evacuate air from the container to a desired vacuum. A sensor disengages the pump when the desired vacuum is achieved, and a timer disengages the pump after a predetermined time. As air is evacuated from the container by the vacuum pump, the air travels from the interior of the container through a mesh screen, a filter, a chamber, and a tube to the outside. Liquids are therefore captured by the mesh screen and filter so they do not damage the pump.

[0009] On the other hand, U.S. Patent Application Publication No. 2014 / 109511, which describes a vacuum packaging sealing device with liquid detection, differs in structure from the present invention. However, rather than relying on a physical barrier, the device nonetheless includes a humidity sensor in the exhaust pipe of the vacuum pump to detect the presence of liquid drawn into the vacuum trough during vacuum sealing. The sensor is electrically connected to a control unit and sends an electrical signal to the control unit. Based on the electrical signal, the control unit controls one or both of the vacuum motor assembly and at least one heat sealing element. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] International Publication No. 2018 / 147813 [Patent Document 2] Chinese Utility Model No. 209284904 [Patent Document 3] Chinese Utility Model No. 212638057 [Patent Document 4] International Publication No. 2008 / 112093 [Patent Document 5] US Patent Application Publication No. 2014 / 109511 Summary of the Invention [Means for solving the problem]

[0011] The technical problem is solved as defined in the independent claims, and preferred embodiments of the invention are defined in the dependent claims. The essence of the portable vacuum pump with protection against the aspiration of liquids is that at least two sensors are provided for detecting liquid at the inlet of the air suction channel of the pump, said sensors being connected to the pump's controller (electronics) which is configured to terminate pumping (vacuum drawing) when liquid is detected by said sensors. The sensors are preferably conductive in order to enable the closure of an electric circuit upon contact with liquid, and thus the termination of pumping.

[0012] An alternative and equally functional solution to the technical problem involves the use of at least one sensor for detecting liquid, which includes a housing with a groove in which a metal element, preferably shaped as a spring, is installed. The metal element is disposed in the groove, which terminates in a plastic plate of the housing. The metal element, preferably a spring, can detect the conductivity of liquid present in the vacuum air in the suction channel, possibly through the plastic plate. If liquid is detected, the metal element is configured to communicate with a controller, typically a printed circuit board assembly (PCBA), which is configured to terminate air suction immediately upon detecting liquid. The metal element is preferably connected to the controller, typically by soldering the metal element to the PCBA. Therefore, no connecting cables or similar devices are required. This embodiment is sensitive because the metal element, i.e., the spring, can easily detect liquid when present.

[0013] The vacuum pump preferably comprises: a housing having at least one opening for connection with a suitable valve, opening or any other structure allowing vacuum storage in a suitable vacuum, container, bag and the like, the interior of which contains at least the following components: a pump for pumping air (vacuuming), powered by a suitable motor and power source, preferably a replaceable or rechargeable battery; a suction channel starting from the opening of the housing and extending into the interior of the housing to establish a path along which air is sucked into the interior of the vacuum pump, said suction channel being preferably provided approximately in the center of the interior of the housing; At least one sensor or at least two sensors with a metal element for detecting liquid, which are provided at the entrance of the suction channel near the point of contact with the valve of the vacuum vessel, bag or other vessel, and which are spaced apart at a distance suitable for receiving a drop of liquid; a housing, in the case of embodiments with at least two sensors, provided with a connecting cable or wire for connecting at least one of the sensors to a controller of the device, typically electronics configured to terminate pumping upon detection of liquid by the sensor; a removable cover for the housing that protects the suction channel and the sensor from environmental conditions, the removal of which allows access to the sensor for maintenance.

[0014] The two sensors are positioned at a distance appropriate for receiving at least a droplet. A suitable distance may be in the range of 1 μm to 5 cm, more preferably 0.5 mm to 0.5 cm, and optimally 1 mm to 2 mm. The sensors may be of any shape, with preferred embodiments including rods and plates. Because the liquid is conductive, the current circuit is closed, thus signaling the electronics to stop pump operation and, therefore, air intake. The sensors are made from a suitable conductive material, preferably nickel-plated brass. The connecting cables or wires for connecting each sensor to the device's controller, typically the electronics, are also made from a conductive material and are connected to the sensors and electronics in any suitable manner known to those skilled in the art. The wires or cables may be positioned anywhere in the vacuum pump, with a preferred location along the side of the pump, toward the sensor at one end and toward the electronics at the second end.

[0015] The shape of the housing opening, the air suction channel, and the dimensions of the sensor are arbitrary, but as mentioned above, the distance between the sensors must be small enough so that even a tiny droplet coming into contact with the sensor can close the circuit and terminate the suction (vacuum).

[0016] If a droplet is trapped between the sensors or detected by a single sensor with the metal element connecting to the pump stationary, the pump must be reset, i.e., the sensor must be dried to enable operation of the device. To accomplish this, the user must remove the removable cover, thus accessing the sensor at the entrance to the suction channel. The sensor is then dried in any known manner, typically by wiping with a dry absorbent material or air drying, thereby opening the circuit between the sensor and the electronics. Closing the removable cover allows the device to be used again. The removable cover thus allows for easy and quick maintenance of the device with easy access to the sensor, which does not require the removal of additional elements or the opening of the housing.

[0017] The removable cover may be designed in any suitable manner, with preferred options being in the form of a silicone sealing strip or a plastic holder with a seal, the housing and the cover or holder respectively being provided with corresponding structures for closure such as threads, click closures, pins and holes, etc. In the case of a silicone sealing strip, no corresponding structure is necessary, as the material and shape of the sealing strip ensure a secure fit into the opening in the housing.

[0018] The pump according to the invention is further provided with known components that allow the pump to operate for air aspiration, i.e. suitable seals for achieving a negative pressure in the housing, etc. These components are known to those skilled in the art and correspond to the usual design of portable vacuum pumps.

[0019] The vacuum pump according to the present invention effectively prevents liquid from being sucked into the pump, thus ensuring a long life and preventing damage to the pump. The vacuum pump according to the present invention can be used with any type of vacuum container, vacuum bag, or any other suitable vessel for storing food or other items.

[0020] The vacuum pump with protection against the suction of liquids according to the invention will be explained in more detail on the basis of the exemplary embodiments and figures shown below. [Brief explanation of the drawings]

[0021] [Figure 1] A vacuum pump according to a possible embodiment, installed in the vacuum vessel. [Figure 2] A vacuum pump according to a possible embodiment installed on a vacuum bag with air flow shown. [Figure 3] Possible embodiments of the vacuum pump when in contact with a liquid. [Figure 4] Cleaning of a vacuum pump according to a possible embodiment. [Figure 5] Cleaning of a vacuum pump according to a possible embodiment. [Figure 6]A second embodiment of the removable part of the housing. [Figure 7] A preferred embodiment of the liquid sensor. [Figure 8] A vacuum pump with a preferred embodiment of the sensor. DETAILED DESCRIPTION OF THE INVENTION

[0022] The vacuum pump according to a possible embodiment comprises a housing with a lower end opening, the interior 1 of which contains the following components: a pump 10 for pumping air (drawing a vacuum) powered by a suitable motor and power supply; a suction channel SC arranged inside the housing; two sensors 3 for detecting the liquid, located at the entrance of the suction channel near the point of contact with the valve of the vacuum container or bag; a connecting cable 4 or wire for connecting the at least one sensor 3 to a controller of the device, typically an electronic device 5 configured to terminate the pumping when liquid is detected by the sensor 3, the connecting cable 4 or wire having an end 4a in contact with said electronic device 5; a removable cover provided with a holder 9 for a seal 8 and a seal 8, which is placed in the lower opening of the housing so that the sensor 3 is accessible when the holder 9 is removed;

[0023] The pump 10, connecting wire 4 and at least a portion of the suction channel SC may be contained within an inner housing that is located inside the main housing of the vacuum pump.

[0024] Figure 1 shows a vacuum pump 1 installed on a vacuum vessel with a lid 2 equipped with a valve 2a, while Figure 2 shows a vacuum pump 1 installed on a valve 6 of a vacuum bag.

[0025] Pressing the ON / OFF button activates the vacuum pump, drawing air from the suction channel through the sensor 3. When a droplet of liquid 7 is aspirated from the vacuum container or bag, it travels toward the suction channel until it reaches the sensor 3, where it is captured and detected, as shown in FIG. 3. Due to the liquid's conductivity, a closed circuit is formed, so the electronics 5 terminates the air suction and the pump stops operating. Terminating the suction prevents further aspiration of liquid, and the user can clean the sensor by removing the seal 8 holder 9 and seal 8 to access the sensor 3, as shown in FIGS. 4 and 5. These can be wiped clean or allowed to air dry, and then the holder 9 with the seal 8 is returned to its original position. After cleaning, the air suction function can be turned on again, and evacuation of the vacuum container or any other vessel can proceed as before.

[0026] Alternatively, the removable part may be designed as a single piece 8' (Fig. 6), which is a silicone seal piece that ensures access to the sensor 3 upon removal. This single piece has a circular shape to fit into the opening of the housing and is provided with appropriate protrusions to ensure the seal and fit to the pump housing. The protrusions also serve as reinforcement and at the same time allow the creation of a labyrinth for air and / or possible liquid, as shown in Fig. 6. The protrusions are formed as a roughly circular base with five legs pointing to the outer periphery of the removable part, while an inner circular formation is located inside the circular base. Furthermore, the function of this part is to ensure a seal when connected to the valve of a vacuum container, bag, or other vessel to enable reliable and efficient evacuation.

[0027] FIG. 7 shows a preferred embodiment of the liquid sensor, which comprises a housing 11, essentially a plastic-based component to be covered with a silicone cover (not shown). The inside of the housing 11 is provided with a groove 11a for receiving a metal spring 14, which is configured to detect all conductive materials through the plastic housing or plate. One end of the metal spring 14 is soldered to a printed circuit board assembly (PCBA) 13, and the other end is installed in the housing groove. The metal spring is placed in the liquid and communicates with the PCBA 13, which stops the pump operation when liquid is detected by the metal spring 14. The air flow connection nozzle 12 is provided for connection to a container to be evacuated and is therefore not connected to the detection of liquid. The housing is also provided with a means for receiving a fixing screw 15 located below the PCBA 13. The fixing screw 15 is intended to attach the sensor housing to a portable vacuum pump.

[0028] Figure 8 shows a pump 10' with a preferred embodiment of the sensor S shown in Figure 7. A housing 11 is fixed to the bottom of the vacuum pump and covers the part that attaches to the article to be vacuumed. A metal spring 14 is present in a groove and a plastic plate 11b covers the entrance of the air suction channel SC' of the pump 10' to detect any possible liquid in the air suction channel SC' by sensing the liquid conductivity.

Claims

1. A portable vacuum pump (10) with protection against the aspiration of liquids, characterized in that at the inlet of an air suction channel (SC) of the pump (10) there are provided at least two sensors (3) for detecting liquid, the sensors (3) being spaced at a distance suitable to receive droplets of liquid, the sensors (3) being connected to a controller (5) of the pump configured to terminate the evacuation when the sensors (3) detect liquid.

2. 2. Portable vacuum pump with protection against the aspiration of liquids according to claim 1, wherein said sensors (3) are placed at a distance ranging from 1 μm to 5 cm, more preferably from 0.5 mm to 0.5 cm, optimally from 1 mm to 2 mm.

3. 3. Portable vacuum pump with protection against the aspiration of liquids according to claim 1 or 2, wherein the sensor (3) is conductive in order to enable the closure of an electric circuit upon contact with liquid and thus the termination of pumping.

4. Portable vacuum pump with protection against the aspiration of liquids according to any one of claims 1 to 3, wherein the sensor (3) is made from nickel-plated brass.

5. Portable vacuum pump with protection against the aspiration of liquids according to any one of claims 1 to 4, wherein the sensor (3) can have any shape, preferably the sensor is formed as a rod or a plate.

6. 1. A portable vacuum pump (10') with protection against the suction of liquids, characterized in that at the inlet of an air suction channel (SC') of the pump (10') there is provided at least one sensor (S) for detecting liquids, the sensor comprising a plastic housing (11) with a groove (11a) for receiving a metal element (14) configured to detect a conductive material in a possible liquid, one end of the metal element (14) being connected to one end of a printed circuit board assembly (13) and the other end of the metal element (14) being installed in the groove (11a) of the housing covered with a plastic plate (11b), the metal element (14) being configured to detect the conductivity of a possible liquid when in contact with the plastic plate (11b).

7. 7. The portable vacuum pump with protection against the aspiration of liquids according to claim 6, wherein the metal element (14) is configured to detect liquid and to communicate with the PCBA (13) in case of detected liquid, the PCBA (13) being configured to cause the pump (10') to stop operation when liquid is sensed by the metal element (14).

8. Portable vacuum pump with protection against the suction of liquids according to claim 6 or 7, wherein the metal element (14) is shaped as a spring.

9. The vacuum pump preferably comprises: A housing having at least one opening for connection with a suitable valve, opening, or any other structure that allows vacuum storage in a suitable vacuum vessel, container, bag, and the like, wherein the housing has at least the following components disposed therein: a pump is provided for pumping air (drawing a vacuum), said pump being powered by a suitable motor and power source, preferably a replaceable or rechargeable battery; The suction channel (SC, SC') is provided starting from the opening of the housing and extending into the interior of the housing to ensure a path, along which air is sucked into the interior of the vacuum pump, and the suction channel (SC, SC') is preferably provided approximately at the center of the interior of the housing; At least one or at least two sensors (3) with a metal spring (14) for detecting the liquid are provided at the entrance of the suction channel (SC, SC') close to the contact point with the valve of the vacuum vessel, bag or other vessel, a housing provided with a connecting cable or wire (4) for connecting said at least one sensor to said controller (5) of the device, typically electronics arranged to terminate pumping when liquid is detected by said sensor; a removable cover for the housing that protects the suction channel and the sensor from environmental conditions, the removal of the cover allowing access to the sensor for maintenance; A portable vacuum pump (10, 10') with protection against the suction of liquids according to any one of claims 6 to 8, comprising:

10. 7. A portable vacuum pump with protection against the aspiration of liquids according to claim 6, wherein the connecting cables or wires for connecting each of the sensors with the controller (5), typically electronics, of the device are also made from a conductive material and connected to the sensors and electronics in any suitable manner.

11. 8. The portable vacuum pump with protection against aspiration of liquids of claim 7, wherein the wires or cables are positioned along the side of the pump towards the sensor at one end and towards the electronics at a second end.

12. 9. A portable vacuum pump with protection against the suction of liquids according to any one of claims 6 to 8, wherein the removable cover is designed in any suitable manner, preferably as a plastic holder (9) with a silicone sealing piece or seal (8), the housing and the holder (9) being provided with corresponding structures for closure, such as threads, click closures, pins and holes and similar structures.

13. 10. The portable vacuum pump with protection against suction of liquids according to claim 9, wherein the removable cover can be designed as an integral part, being a silicone sealing piece having a circular shape that ensures access to the sensor when removed and fits into the opening in the housing, with appropriate protrusions to ensure sealing and fitting of the pump to the housing.

14. 11. A portable vacuum pump with protection against the suction of liquids as claimed in claim 10, wherein the protrusion forms a labyrinth for air and / or possible liquids and is formed as a substantially circular base with five legs pointing to the outer periphery of the removable part, and inside the circular base there is an inner circular formation.

15. 15. A portable vacuum pump with protection against the aspiration of liquids according to any one of claims 6 to 14, wherein the pump is configured for use with any type of vacuum container, vacuum bag, or any other suitable vessel for storing food or other items.

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