CN203034574U - Explosion-proof pressure type closestool water tank - Google Patents
Explosion-proof pressure type closestool water tank Download PDFInfo
- Publication number
- CN203034574U CN203034574U CN 201320050878 CN201320050878U CN203034574U CN 203034574 U CN203034574 U CN 203034574U CN 201320050878 CN201320050878 CN 201320050878 CN 201320050878 U CN201320050878 U CN 201320050878U CN 203034574 U CN203034574 U CN 203034574U
- Authority
- CN
- China
- Prior art keywords
- water
- water storage
- storage bag
- gas storage
- courage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Landscapes
- Emergency Lowering Means (AREA)
Abstract
The utility model discloses an explosion-proof pressure type closestool water tank which comprises a sealed gas storage container mainly used for storing gas, and a sealed water storage container used for storing water. The water storage container is provided with a water outlet and a water inlet. The limit pressure resisting value of the gas storage container is larger than that of the water storage container. The gas storage container is communicated with the water storage container through a channel, and air in the water storage container can be discharged into the gas storage container through the channel. The explosion-proof pressure type closestool water tank achieves safety through utilization of the limit pressure resisting difference of the gas storage container and the limit pressure resisting difference of the water storage container, when the water storage container cracks, compressed air in the gas storage container can be stably released, and big explosion of the pressure type closestool water tank is avoided, and personal safety and property safety of users in the using process can be guaranteed.
Description
Technical field
The utility model relates to a kind of pressure type water-closet tank in bathroom field, particularly relates to a kind of explosion-proof type pressure type water-closet tank.
Background technology
Traditional water-closet tank mainly is that water has certain speed and reaches the purpose of cleaning closestool urinal when relying on the pressure of water tank middle water level and the drop generation of toilet urinal middle water level to make Water flushing for cistern, yet, when the height of water hour, its wash away dynamics a little less than, need the dirt in the toilet urinal could be washed away totally with more water.For this reason, a kind of pressure type water-closet tank has appearred in prior art.As shown in Figure 1, this pressure type water-closet tank is to adopt totally enclosed casing 1 ＇ as inner bag, this casing 1 ＇ can store certain air when water filling, utilize hydraulic pressure in the water supply line to compress the air of box house, compressed air forms power, the pressure of adding water itself forms dual-pressure, when washing away action by flushing valve 2 ＇, water tank discharges its energy, force water to charge into the toilet urinal from the outfall of casing 1 ＇ rapidly, the function of economizing on water again when reaching powerful washing away.Facts have proved, this pressure type water-closet tank of prior art, its scouring effect and water-saving result all are better than the main water-closet tank that relies on the gravity bath of tradition greatly.
The pressure type water-closet tank of prior art because its inner bag adopts metal material to realize, exist with high costs, with weak points such as its energy-saving benefit can't be directly proportional, cause it to be widely used.To this, many manufacturers begin to replace expensive metal to make the inner bag of water tank with reinforced plastic, because this type of water tank manufacturing process maturation, with low cost, reliability is preferable, add being used of control pressurer system (as pressure maintaining valve 3 ＇ among Fig. 1) and safety device (as safety valve 4 ＇ among Fig. 1), make it obtain producing in enormous quantities and putting goods on the market, enter huge numbers of families.Yet this scouring effect and water-saving result are good just, cost is low, obtain popular universally recognized pressure type water-closet tank, have but become one of security threat potential in people's life.This be because, this pressure type water-closet tank is too high at pressure of supply water, product is because of the manufacture craft defective simultaneously, the long-term use when causing liner material fatigue, aging or safety device to go wrong, the internal pressure of inner water tank sharply raises and can't effectively be discharged, cause inner bag blast suddenly under the effect of crunch of water tank, shock wave can be scraped the ceramic package of water tank and be formed sharp shell fragment, causes the great bodily injury of the person, property to the user.
The utility model content
The purpose of this utility model is to overcome the deficiency of prior art, a kind of explosion-proof type pressure type water-closet tank is provided, it efficiently solves the contradiction between cost and the safety, make pressure type water-closet tank inner bag avoid taking place the huge explosion phenomenon, finally also only cracking phenomena can take place, and steadily discharge its gas pressure.
The technical scheme that its technical problem that solves the utility model adopts is: a kind of explosion-proof type pressure type water-closet tank, comprise the airtight gas storage courage that is mainly used in stored-gas and the airtight water storage bag that is used for water storage, and water storage bag is provided with outfall and water inlet; The limit withstand voltage of gas storage courage is greater than the limit withstand voltage of water storage bag, and the gas storage courage is connected with water storage bag by passage, enters in the gas storage courage by passage for the air in the water storage bag.
One termination of described passage is led to described gas storage courage, and the other end of described passage is positioned at the top of described water storage bag.
Described gas storage courage is positioned at outside the described water storage bag.
Described gas storage courage is wrapped in the described water storage bag.
Described passage is pipeline, and described gas storage courage is connected in the end sealing of this pipeline, and the other end sealing of this pipeline is stretched in the described water storage bag, and is positioned at the inside top of described water storage bag.
Described passage is pipeline, and described gas storage courage is connected in the sealing of an end of this pipeline, and the other end of this pipeline described water storage bag top that is tightly connected enters described gas storage courage for the air in the described water storage bag by this pipeline.
Described passage is the hole, and described gas storage courage is positioned on the described water storage bag, is connected by the hole between the bottom of described gas storage courage and the top of described water storage bag.
Described passage is pipeline, and an end of this pipeline extends the inside bottom of described gas storage courage, and the other end of this pipeline is positioned at the inside top of described water storage bag.
A kind of explosion-proof type pressure type water-closet tank of the present utility model, be to utilize the limit pressure difference between water storage bag and the gas storage courage to reach its safety: when water storage bag is intake, under the pressure action of water, air in the water storage bag is rushed in the gas storage courage fully or basically fully to be compressed, and forms compressed air; During Water flushing for cistern, the gas storage courage is expelled to water storage bag with compressed air, makes the water in the water storage bag be subjected to the compressed-air actuated crunch effect in top and bath downwards rapidly, reaches the powerful function of washing away and economizing on water; If the pressure of supply water of water storage bag is excessive, and water tank can not normally discharge its internal pressure or water storage bag because of the manufacturing process defective, the long-term use caused the water storage bag fatigue of materials, wear out when its withstand voltage is descended, cracking phenomena can take place earlier in water storage bag, because compressed air is restricted in the gas storage courage, and the crunch of gas storage courage compressed air can steadily discharge by the passage that the gas storage courage is connected with water storage bag, therefore, also only be water storage bag generation cracking phenomena this moment, a large amount of compressed air can't occur sharply erupts and the phenomenon of formation huge explosion, so can not destroy the ceramic package of water tank, thereby can effectively stop the person to the user, the accident that property damages takes place.
Compare with the pressure type water-closet tank of prior art, the beneficial effects of the utility model are, be divided into water storage bag and gas storage courage owing to the pressure type water-closet tank is used for originally the inner bag of while water storage and gas storage, and the limit withstand voltage of gas storage courage is greater than the limit withstand voltage of standpipe, water storage bag is connected by passage with the gas storage courage, enter in the gas storage courage by passage for the air in the water storage bag, it is excessive to make that in a single day pressure of supply water takes place water storage bag, and in the time of can not normally discharging the reduction of its internal pressure or water storage bag withstand voltage, also only be that the phenomenon that cracking leaks takes place water storage bag, can't blast and burst the phenomenon of water tank ceramic package, this is because a large amount of air can be stored in the gas storage courage and isolated with water storage bag in the water tank, and can steadily discharge by the passage that the gas storage courage is connected with water storage bag, thereby the phenomenon of formation huge explosion the rapid eruption of a large amount of compressed air can not appear and.Therefore, the utility model can be avoided pressure type water-closet tank generation huge explosion event, and user's its personal safety and safety of property in use is protected.
Below in conjunction with drawings and Examples the utility model is described in further detail; But a kind of explosion-proof type pressure type water-closet tank of the present utility model is not limited to embodiment.
Description of drawings
Fig. 1 is the generalized section of the pressure type water-closet tank of prior art;
Fig. 2 is the generalized section of embodiment one pressure type water-closet tank of the present utility model;
Fig. 3 is the generalized section (water storage bag water inlet) of embodiment one pressure type water-closet tank of the present utility model;
Fig. 4 is the generalized section (water storage bag bath) of embodiment one pressure type water-closet tank of the present utility model;
Fig. 5 is the generalized section (the water storage bag pressure of supply water is excessive, normal release pressure) of embodiment one pressure type water-closet tank of the present utility model;
Fig. 6 is the generalized section (water storage bag ftractures) of embodiment one pressure type water-closet tank of the present utility model;
Fig. 7 is the generalized section of embodiment two pressure type water-closet tanks of the present utility model;
Fig. 8 is the generalized section of embodiment three pressure type water-closet tanks of the present utility model.
The specific embodiment
Embodiment one:
See also shown in Figure 2ly, a kind of explosion-proof type pressure type water-closet tank of the present utility model comprises airtight gas storage courage 2 and an airtight water storage bag 1 that is mainly used in storing water that is mainly used in stored-gas.The bottom of water storage bag 1 is provided with outfall 12, and sidewall is provided with water inlet 11, and this water storage bag 1 is equipped with the flushing valve 3 of opening or closing for its outfall 12 of control, and the water inlet 11 of this water storage bag connects extraneous water supply line 7 by a pressure maintaining valve 4.What gas storage courage 2 was mainly used in that stored-gas refers to adorn under the normal conditions in the gas storage courage 2 is gas, when some special circumstances take place, when for example the pressure of supply water of water storage bag 1 is excessive, also a part of water may be housed in the gas storage courage 2.The limit withstand voltage of gas storage courage 2 is greater than the limit withstand voltage of water storage bag 1, and this gas storage courage 2 is interconnected by passage and water storage bag 1 outside water storage bag 1, so that the air in the water storage bag 1 can enter in the gas storage courage 2 basically fully by passage.
As a kind of preferred, the passage that is communicated with between above-mentioned gas storage courage 2 and the water storage bag 1 is pipeline 8.Specifically, one end opening of this pipeline 8 is called throttle orifice 81(makes it satisfy the condition of washing away by the setting to the cross sectional area of throttle orifice 81), this end of this pipeline 8 and the bottom sidewall of gas storage courage 2 are tightly connected, this pipeline 8 is connected with gas storage courage 2, the remainder of this pipeline 8 then stretches in the water storage bag 1, and its other end is positioned at the inside top of water storage bag 1, makes the air in the water storage bag 1 all enter gas storage courage 2 basically by this pipeline 8.
The bottom of above-mentioned water storage bag 1 also is provided with a pressure release orifice 13, and these pressure release orifice 13 places adopt spring 6 that a safety valve 5 is housed.
Above-mentioned flushing valve 3 specifically comprises drain valve stem 31 and sealing piston 32, drain valve stem 31 parts are stretched in the water storage bag 1 from the end sealing of water storage bag 1, sealing piston 32 is fixed in the bottom of drain valve stem 31, and leaves or block the outfall 12 of water storage bag with moving up and down of drain valve stem 31.
A kind of explosion-proof type pressure type water-closet tank of the present utility model, see also shown in Figure 3, wherein dotted line is represented water, arrow is represented the flow direction of air, and during water storage bag 1 water inlet, the water of water supply line 7 enters in the water storage bag 1 after pressure maintaining valve 4 is regulated, because air is light and be gathered in the inside upper part of water storage bag 1, therefore when the water storage bag inner inlet, the air of water storage bag inner and upper is driven owing to the hydraulic pressure effect, and enters gas storage courage 2 by pipeline 8; When water inlet was finished, the pressure of water storage bag 1 and gas storage courage 2 reached balance, and just was full of water basically in the water storage bag 1, and undischarged minute quantity air energy is very limited in this water storage bag 1, is not enough to constitute security threat.See also shown in Figure 4, wherein dotted line is represented water, arrow is represented the flow direction of air, during Water flushing for cistern, upwards mention drain valve stem 31, make sealing piston 32 break away from the outfall 12 of water storage bag, then water storage bag 1 internal pressure reduces, gas storage courage 2 drains into the air of compression in the water storage bag 1 by throttle orifice 81, pipeline 8, makes the water in the water storage bag 1 be subjected to the compressed-air actuated crunch in top and bath downwards rapidly, reaches the powerful purpose of washing away and economizing on water.
See also shown in Figure 5, wherein dotted line is represented water, when pressure maintaining valve 4 damages, when making the pressure of supply water of water storage bag excessive, the water of water supply line 7 will continue to enter in the water storage bag 1, and be full of basically whole water storage bag 1 back under the high pressure effect in pipeline 8 enters gas storage courage 2, make to enter a certain amount of water in the gas storage courage 2, make the air in the gas storage courage 2 further obtain compression simultaneously.At this moment, the internal pressure of water storage bag 1 rises, and the elastic force that causes safety valve 5 to overcome spring 6 is pushed down and opens the pressure release orifice 13 of water storage bag, and the internal pressure of water storage bag 1 is effectively discharged by its pressure release orifice, reaches security purpose.
See also shown in Figure 6, wherein dotted line is represented water, when pressure maintaining valve 4 damages, and safety valve 5 lost efficacy and makes water storage bag 1 can not normally discharge its internal pressure or water storage bag 1 because of the manufacturing process defective, the long-term use caused the water storage bag fatigue of materials, the aging grade and when its withstand voltage is descended, because the limit withstand voltage of water storage bag 1 is lower than the limit withstand voltage of gas storage courage 2, therefore the phenomenon that cracking leaks can take place earlier in water storage bag 1 under the hydraulic pressure effect, the compressed air that tool kills and wounds energy then is restricted in the gas storage courage 2 that separates mutually with water storage bag 1, and can only steadily discharge by throttle orifice 81 and pipeline 8 and (earlier the low amounts of water that enters is discharged by throttle orifice 81 and pipeline 8 in the gas storage courage 2, exhaust again), so can not work the mischief to external world.Therefore, pressure type water-closet tank of the present utility model, in case the cracking drainage takes place in its water storage bag 1, a large amount of compressed air can't occur sharply erupts and the phenomenon of formation huge explosion, namely can not destroy the ceramic package of water tank, can effectively stop the person to the user, the accident generation that property damages, make user's personal safety and safety of property can access effective guarantee.
Embodiment two:
See also shown in Figure 7, a kind of explosion-proof type pressure type water-closet tank of the present utility model, the difference of itself and embodiment one is: its gas storage courage 2 is wrapped in the inside of water storage bag 1.Identical with embodiment one, this gas storage courage 2 is that passage is communicated with water storage bag with pipeline 8 also, different is, one end of pipeline 8 extends the inside bottom of gas storage courage 2 by the top of gas storage courage 2, the other end of pipeline 8 is positioned at the inside top of water storage bag 1, and this end opening of pipeline 8 constitutes throttle orifice 81.This way can make the air of water storage bag 1 enter fully basically in the gas storage courage 2 on the one hand, in the time of can entering low amounts of water in gas storage courage 2 on the other hand, earlier this low amounts of water is discharged by pipeline 8.During water tank water intake, the air in the water storage bag 1 is caught up with in the gas storage courage 2 by throttle orifice 81 and pipeline 8 under the effect of hydraulic pressure equally; During Water flushing for cistern, the air in the gas storage courage 2 drains in the water storage bag 1 equally, makes the water in the water storage bag 1 be subjected to the compressed-air actuated crunch in top and bath downwards rapidly, reaches the powerful purpose of washing away and economizing on water; When the pressure of supply water of water storage bag 1 excessive, and safety valve 4 inefficacies or water storage bag 1 are because of the manufacturing process defective, the long-term use caused water storage bag fatigue of materials, aging etc. and when its withstand voltage is descended, cracking can take place earlier and leak in water storage bag 1 equally under the hydraulic pressure effect, compressed air in the gas storage courage 2 then steadily discharges by pipeline 8 and throttle orifice 81, can not work the mischief to external world equally.
Embodiment three:
See also shown in Figure 8, a kind of explosion-proof type pressure type water-closet tank of the present utility model, the difference of itself and embodiment one is: the quantity of its gas storage courage 2 and water storage bag 1 respectively is two, and two adjacent gas storage courages adopt through hole 21 to be communicated with between its sidewall bottom, and two adjacent water storage bags adopt water hole 14 to be communicated with between top side wall and bottom respectively.The same with embodiment one, the same pipeline 8 that adopts is communicated with between adjacent gas storage courage and the water storage bag, and the water storage bag adjacent with the gas storage courage is provided with drain hole 12, and flushing valve 3 is housed, and another water storage bag is provided with water inlet 11, and safety valve 5 is housed.Adopt this explosion-proof type pressure type water-closet tank, can normally advance water and flush action equally, and can avoid equally the huge explosion event takes place, user's personal safety and safety of property is effectively ensured constantly.This embodiment three is explanation, and the quantity of gas storage courage of the present utility model and water storage bag is not limited to one, also can be respectively two, and even more than two.
A kind of explosion-proof type pressure type water-closet tank of the present utility model also can be that passage is communicated with the hole between its gas storage courage and the water storage bag, for example, the gas storage courage is positioned on the water storage bag, and both are separated by a chamber wall, at this chamber wall the hole are set, and both are interconnected.Adopt this embodiment, in the time of can making water storage bag reach operating pressure, just be full of water in this water storage bag, reach the purpose of avoiding pressure type water-closet tank generation huge explosion simultaneously.
A kind of explosion-proof type pressure type water-closet tank of the present utility model, when the gas storage courage is positioned at outside the water storage bag, and when adopting pipeline to be communicated with between gas storage courage and the water storage bag, also can adopt the connected mode that is different from above-described embodiment one, for example, the one end sealing of pipeline can be connected the gas storage courage, and be connected with the sidewall bottom of gas storage courage as a kind of end of pipeline that preferably can make equally; Water storage bag is connected in the other end sealing of pipeline, and for water storage bag can be entered air in the gas storage courage fully or basically fully, the other end of pipeline is connected with the end face highest point of water storage bag, perhaps, when the apical side height of water storage bag is consistent, the other end of pipeline is connected everywhere with the sidewall top of water storage bag.In like manner, adopt this embodiment, in the time of can making water storage bag reach operating pressure equally, just be full of water in this water storage bag or be full of water basically, and reach the purpose of avoiding pressure type water-closet tank generation huge explosion.
Above-described embodiment only is used for further specifying a kind of explosion-proof type pressure type water-closet tank of the present utility model; but the utility model is not limited to embodiment; every foundation technical spirit of the present utility model all falls in the protection domain of technical solutions of the utility model any simple modification, equivalent variations and modification that above embodiment does.
Claims (8)
1. explosion-proof type pressure type water-closet tank is characterized in that: comprise the airtight gas storage courage that is mainly used in stored-gas and the airtight water storage bag that is used for water storage, water storage bag is provided with outfall and water inlet; The limit withstand voltage of gas storage courage is greater than the limit withstand voltage of water storage bag, and the gas storage courage is connected with water storage bag by passage, enters in the gas storage courage by passage for the air in the water storage bag.
2. explosion-proof type pressure type water-closet tank according to claim 1, it is characterized in that: a termination of described passage is led to described gas storage courage, and the other end of described passage is positioned at the top of described water storage bag.
3. explosion-proof type pressure type water-closet tank according to claim 1 and 2, it is characterized in that: described gas storage courage is positioned at outside the described water storage bag.
4. explosion-proof type pressure type water-closet tank according to claim 1 and 2, it is characterized in that: described gas storage courage is wrapped in the described water storage bag.
5. explosion-proof type pressure type water-closet tank according to claim 3, it is characterized in that: described passage is pipeline, described gas storage courage is connected in the one end sealing of this pipeline, and the other end sealing of this pipeline is stretched in the described water storage bag, and is positioned at the inside top of described water storage bag.
6. explosion-proof type pressure type water-closet tank according to claim 3, it is characterized in that: described passage is pipeline, described gas storage courage is connected in the one end sealing of this pipeline, the other end of this pipeline described water storage bag top that is tightly connected enters described gas storage courage for the air in the described water storage bag by this pipeline.
7. explosion-proof type pressure type water-closet tank according to claim 3, it is characterized in that: described passage is the hole, described gas storage courage is positioned on the described water storage bag, is connected by the hole between the bottom of described gas storage courage and the top of described water storage bag.
8. explosion-proof type pressure type water-closet tank according to claim 4, it is characterized in that: described passage is pipeline, and an end of this pipeline extends the inside bottom of described gas storage courage, the other end of this pipeline is positioned at the inside top of described water storage bag.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320050878 CN203034574U (en) | 2013-01-29 | 2013-01-29 | Explosion-proof pressure type closestool water tank |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320050878 CN203034574U (en) | 2013-01-29 | 2013-01-29 | Explosion-proof pressure type closestool water tank |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203034574U true CN203034574U (en) | 2013-07-03 |
Family
ID=48686708
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201320050878 Expired - Lifetime CN203034574U (en) | 2013-01-29 | 2013-01-29 | Explosion-proof pressure type closestool water tank |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203034574U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103967095A (en) * | 2013-01-29 | 2014-08-06 | 李才有 | Explosion-proof method for pressure type toilet water tank and explosion-proof pressure type toilet water tank |
-
2013
- 2013-01-29 CN CN 201320050878 patent/CN203034574U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103967095A (en) * | 2013-01-29 | 2014-08-06 | 李才有 | Explosion-proof method for pressure type toilet water tank and explosion-proof pressure type toilet water tank |
| CN103967095B (en) * | 2013-01-29 | 2015-11-25 | 李才有 | A kind of explosion-proof method of pressure-type toilet water tank and explosion-proof type pressure-type toilet water tank |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100491659C (en) | Key-controlling air pressure type flushing device | |
| CN103967095B (en) | A kind of explosion-proof method of pressure-type toilet water tank and explosion-proof type pressure-type toilet water tank | |
| CN203034574U (en) | Explosion-proof pressure type closestool water tank | |
| CN207454852U (en) | A kind of double-direction relief valve | |
| CN203303548U (en) | Outdoor fire hydrant for automatically discharging residual water | |
| CN106065648A (en) | A kind of water-saving toilet without cistern with pressure flush system and assemble method thereof | |
| CN103046615A (en) | Pressure-stabilizing water-air isolated water storage tank and pump station | |
| CN104343171B (en) | A kind of supercharging air drainage arrangement and its water discharge method and toilet | |
| CN203162551U (en) | Overpressure leakage preventing pipeline drainer | |
| CN201778385U (en) | Floor drain | |
| CN201272991Y (en) | Pressure type water tank | |
| CN104674919A (en) | Pressure type water flushing device and constant-pressure water flushing method | |
| CN107339471B (en) | Diaphragm buffer type rubber flap check valve | |
| CN103485401A (en) | Flush toilet water tank | |
| CN203487600U (en) | Air supercharging drainage device and water closet | |
| CN2747290Y (en) | Pneumatic flushing device | |
| CN101818823A (en) | Tap water cut-off leakage-proof protection valve device | |
| CN2839400Y (en) | Assembling closet supercharging bath device | |
| CN2747289Y (en) | Squat type pneumatic flushing device | |
| CN201546284U (en) | Environment-friendly water-saving water tank | |
| CN201050104Y (en) | Low water-pressure air-pressure type water tank device for pressure flushing toilet seat | |
| CN2431324Y (en) | Air bag type pressure flushing cistern | |
| CN2491503Y (en) | Air bag type flushing pressure cistern for toilet | |
| CN202689133U (en) | Simple long tubular sanitary fittings water tank | |
| CN101139846A (en) | Non-liner energy-accumulation double impulsion water tank |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20130703 Effective date of abandoning: 20151125 |
|
| C25 | Abandonment of patent right or utility model to avoid double patenting |