Liquid gas level measuring system

Abstract

The present invention relates to a liquid gas level measuring system for use in a liquid gas tank and designed to cooperate with a float level gauge head mounted on the gas tank and made of magnetically inert material. The system comprises a dial module 1 attachable to the float level gauge head and a sensor module 2 releasably connected to the dial module 1. The dial module 1 is provided with at least one directing dial magnet 103 magnetically coupled with a drive magnet of the float level gauge. The sensor module includes a Hall effect sensor, a battery 204 and a radio module with an antenna 205, allowing wireless measurement data transmission to a remote location.

Claims

1. A liquid gas level measuring system for use in a liquid gas tank and designed to cooperate with a float level gauge head mounted on the liquid gas tank and made of magnetically inert material, the system comprising a dial magnet, a Hall effect sensor, a battery, a radio module with an antenna, characterised in that the system comprises: a dial module attachable to the float level gauge head and comprising: a dial module body having its bottom face shaped so as to be mounted in the level gauge head, an indicating rotary element arranged in the dial module body and serving for visual indication of liquid gas level in the liquid gas tank, at least one dial magnet arranged below the indicating rotary element, whereby said at least one dial magnet and the indicating rotary element are arranged such that, during rotation about a common vertical rotation axis, a rotation angle of said at least one dial magnet corresponds to the rotation angle of the indicating rotary element, a tank volume scale circular in shape and adjusted to cooperate with the indicating rotary element so as to indicate percentage of a tank volume occupied by the liquid gas, and a dial module lid provided on its top face with at least one connection element, whereby at least part of the dial module lid peripheral area is made of a transparent material, and a sensor module releasably connected to the dial module and comprising: a housing provided with at least one connection element corresponding to the at least one connection element of the dial module lid and adapted to form a releasable connection with the at least one connection element of the dial module lid, an electronic module comprising the Hall effect sensor and the radio module, a battery connected to the electronic module, the antenna connected to the radio module; wherein the dial module comprises also a cylindrical guide magnet arranged above the indicating rotary element and cooperating with said at least one dial magnet, whereby said at least one dial magnet, the indicating rotary element and the cylindrical guide magnet are arranged such that, during rotation about the common vertical rotation axis, the rotation angle of said at least one dial magnet corresponds to the rotation angle of both the indicating rotary element and the cylindrical guide magnet.

2. The liquid gas level measuring system according to claim 1, wherein the releasable connection formed by the connection elements of both the dial module lid and the housing is a click-in connection.

3. The liquid gas level measuring system according to claim 2, wherein the at least one connection element of the dial module lid is formed as a socket having engaging means, and the housing in its lower part is formed as the at least one connection element fitting the inner shape of the socket and is provided with engaging means corresponding to the engaging means of the socket.

4. The liquid gas level measuring system according to claim 3, wherein the indicating rotary element is a dial disc, which on its surface facing the cylindrical guide magnet is peripherally provided with the tank volume scale.

5. The liquid gas level measuring system according to claim 4, wherein a single dial magnet is arranged axially below the dial disc.

6. The liquid gas level measuring system according to claim 4, wherein two dial magnets are arranged symmetrically below the dial disc.

7. The liquid gas level measuring system according to claim 3, wherein the indicating rotary element is a gauge pointer, and the tank volume scale is formed as a circular insert fixed inside the dial module body facing said at least one dial magnet.

8. The liquid gas level measuring system according to claim 1, wherein the dial module body and the dial module lid are connected to each other by gluing.

9. The liquid gas level measuring system according to claim 1, wherein the connection between the dial module lid and the housing is sealed.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) Preferred embodiments of the present invention are presented in a more detailed manner with reference to the attached drawing, in which:

(2) FIG. 1 shows an exploded view of a preferred embodiment of the liquid gas level measuring system according to the invention;

(3) FIG. 2 shows an exploded of view of an alternative preferred embodiment of the liquid gas level measuring system according to the invention;

(4) FIG. 3 shows an exploded view of a preferred embodiment of the dial module with a rotary dial disc;

(5) FIG. 4 shows an exploded view of an alternative preferred embodiment of the dial module with a rotary gauge pointer;

(6) FIG. 5 shows a top view of the system of FIG. 2;

(7) FIG. 6 shows a perspective view of a preferred embodiment of the sensor module in assembled state;

(8) FIGS. 7A, 7B show two alternative embodiments of arrangement of dial magnet(s) with respect to the dial disc.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(9) FIGS. 1 and 2 show two preferred embodiments of the liquid gas level measuring system according to the invention. The system comprises two modules releasably connected together. The first module, i.e. a dial module 1 is attachable to the float level gauge head of a liquid gas tank (not shown). The dial module 1 comprises a dial module body 101 having its bottom face shaped so as to be mounted in the level gauge head (not shown). The dial module body 101 on its periphery is provided with two lugs extending outwardly and arranged opposite one another. These lugs serve to accept screws (typically cross screws), fixing the dial module body 101 to the level gauge head. The dial module 1 comprises also a dial module lid 105, which on its top face has a socket 106. The dial module lid 105 at least on the area outside the socket 106 is made of a transparent material, which allows visual inspection of the liquid gas level. Further details of the dial module 1 components contained in the space between the dial module body 101 and the lid 105 are explained below with reference to two alternative embodiments of the dial module 1, shown in FIGS. 3 and 4, respectively.

(10) As mentioned above, FIGS. 3 and 4 show two alternative embodiments of the dial module 1 of the invention. In both embodiments between the dial module body 101 and the dial module lid 105 the following elements are enclosed: an indicating rotary element, a single dial magnet 103, a cylindrical guide magnet 104, a tank volume scale 108 and a positioning insert 109. The indicating rotary element is arranged in the dial module body 101 and serves for visual indication of liquid gas level in the tank. The dial magnet 103 is arranged below the indicating rotary element and cooperates with the cylindrical guide magnet 104 arranged above the indicating rotary element. The dial magnet 103, the indicating rotary element and the guide magnet 104 are arranged coaxially on the same vertical rotary axle. The tank volume scale 108 is circular in shape and is adjusted to cooperate with the indicating rotary element so as to indicate percentage of the tank volume occupied by the liquid gas. The positioning insert 109 is provided between the guide magnet 104 and the dial module lid 105. The positioning insert 109 is provided with a window 110 on part of its surface. In both alternative embodiments of the dial module 1 shown in FIGS. 3 and 4, respectively, the socket 106 of the dial module lid 105 is provided with engaging means 107.

(11) In the preferred embodiment of the dial module 1 shown in FIG. 3 the indicating rotary element is a dial disc 102a, which on its surface facing the guide magnet 104 is peripherally provided with the tank volume scale 108. Thus, visual inspection of the liquid gas level is based on determination of the scale-bearing dial disc 102a position, which can be viewed by an observer through the inspection window 110 and the transparent peripheral part of the dial module lid 105 outside the socket 106.

(12) In the alternative embodiment of the dial module 1 shown in FIG. 4 the indicating rotary element is a gauge pointer 102b, and the tank volume scale 108 is formed as a circular insert fixed inside the dial module body 101 facing the dial magnet 103. In this case visual inspection of the liquid gas level involves determination of the relative position of the gauge pointer 102b and the scale 108 provided on the circular insert fixed inside the dial module body 101. Again, this relative position of the gauge pointer 102b and the scale 108 can be viewed by an observer through the inspection window 110 and the transparent peripheral part of the dial module lid 105 outside the socket 106.

(13) Coming back to FIGS. 1 and 2 illustrating two alternative preferred embodiments of the system according to the invention, the second module of both these preferred embodiments is a replaceable sensor module 2. FIG. 6 shows a perspective view of the sensor module in assembled state. The sensor module 2 comprises a housing 201, which in its lower part is formed to fit the inner shape of the socket 106 of the dial module 1, and which is provided with engaging means 202 (shown in FIG. 6) that correspond to the engaging means 107 of the socket 106 and together with them form a releasable click-in connection. Further, the sensor module 2 comprises a electronic module 203 comprising the Hall effect sensor and the radio module. Yet further, the sensor module 2 comprises a battery 204 (such as lithium battery) connected to the electronic module 203. Both the electronic module 203 and the battery 204 are arranged inside the housing 201. The sensor module 2 also comprises an antenna 205 connected to the electronic module 203 and extending outside the housing 201 through a passage provided with a sealing flange 206. In the preferred embodiments shown in FIGS. 1 and 2 the sensor module housing 201 comprises a housing cap 201a. However, the housing 201 can be also formed differently, as long as it provides safe space for the electronic module 203, the battery 204 and other optional elements required to perform the sensor module 2 function.

(14) Once connected, the dial module body 101 and the dial module lid 105 enclose the elements contained therebetween in a tight and weatherproof manner. Similarly, the housing 201 encloses the electronic module 203 and the battery 204 in a tight and weatherproof manner. Preferably, all these external elements, i.e. the dial module body 101, the lid 105 and the sensor module housing 201 are made of a shock-resistant material such as polycarbonate, or other materials showing similar properties. This allows to use the system of the invention to be used outdoor in any atmospheric conditions all year round and to protect the other system elements from mechanical damage.

(15) FIG. 5 shows a top view of the preferred embodiment of the system of FIG. 2. In this orientation it is clear that the indication of the liquid gas level in the tank can be determined independently by means of the sensor module 2, which can further transmit the measurement results to a remote location by radio (the antenna 205 extending upwards from the sensor module housing 201 is shown in FIG. 5), and by visual inspection of the gauge pointer 102b with respect to the tank volume scale 108 visible through transparent windows 110 of the positioning insert 109 and the transparent peripheral area of the dial module lid 105.

(16) Further, FIG. 7A shows a preferred embodiment of the system according to the invention, wherein a single dial magnet 103 is arranged axially below the dial disc 102a. In an alternative embodiment shown in FIG. 7B two dial magnets 103 are arranged symmetrically below the dial disc 102a.

(17) The operation of the liquid gas level measuring system according to the invention is as follows. The float level gauge installed in the gas tank converts the liquid gas level to rotation angle of the vertical rotary axle connected to the level gauge. A drive magnet (not shown) is provided at the top end of the vertical rotary axle of the level gauge. This magnet is generally enclosed in the level gauge housing made of magnetically inert material. As the magnet is fixed to the rotary axle it rotates along with it. In this way the liquid gas level in the tank corresponds to the inclination angle of the magnetic field. The level gauge head is connected to the tank (commonly by means of hex(interior) screws). It is essential for safe utilization of the tank that this connection is properly sealed. Thus, it is recommended not to manipulate it at all, unless necessary. As explained above, the dial module 1 is mounted on the level gauge head once (by the tank manufacturer or an authorised service) and there is no need to detach it during normal use of the tank. Due to magnetic coupling with the dial magnet 103 (or dial magnets 103) arranged below the indicating rotary element (either in form of the dial disc 102a or the gauge pointer 102b) the rotation of the drive magnet of the float level gauge (master magnet) causes corresponding rotation of the dial magnet(s) 103 (103) [slave magnet(s)]. Since the dial magnet(s) 103 (103) and the indicating rotary element are arranged such that during rotation about the common vertical rotation axis the rotation angle of the dial magnet(s) 103 (103) corresponds to the rotation angle of the indicating rotary element, any rotation of the drive magnet results in corresponding rotation of the indicating rotary element about the vertical rotation axis. Magnetic field changes resulting from the rotation of the slave magnet, i.e. the dial magnet(s) 103 (103) are detected by the magnetic field sensor of the sensor module 2. In the preferred embodiments discussed above the dial module comprises an additional guide magnet 104 arranged above arranged axially above the indicating rotary element. This guide magnet 104 can be defined as a secondary slave magnet, modifying the magnetic field generated by the dial magnet(s) 103 (103) acting here as primary slave magnet(s) so as to improve the quality of the measurement completed by the sensor module 2. The guide magnet 104 is carefully selected to a given magnetic field level, so as to allow proper operation of the sensor module 2.

(18) However, it is also possible to provide the sensor module 2 of a type showing so improved detection capability that no aid of the guide magnet 104 is required. In such case the sensor module 2 detects the changes in magnetic field of the dial magnet(s) 103 (103) only.

(19) Preferably, the electronic module 203 used in the liquid gas level measuring system according to the invention is based on IoT (Internet of Things) concept. The IoT-based sensor module 2 allows the liquid gas level data to be transmitted periodically to the remotely located server of the service provider, thereby allowing to avoid fuel stockout, enhance distribution, relieve the customer/final user from the need of monitoring the fuel inventory. The liquid gas level data can be also transmitted periodically by the IoT-based sensor module 2 to home display or a mobile application to allow the customer/final user to behave in a more energy-efficient manner, inspect proper operation of the fuel provider and negotiate the delivery price based on the actual fuel consumption status. Use of IoT-based electronic module 203 is opening new communication opportunities, showing such advantages as significant device cost reduction, growing communication network opportunities and using different specific data transmission standards such as LoRa WAN or Sigfox, depending on the user preferences.