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(11) | EP 3 018 413 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | A CONTROL DEVICE FOR A GAS OVEN |
| (57) A control device for gas ovens, comprising: a valve body (2) exhibiting an inlet
opening (3) for combustible gas and an outlet opening (4) for combustible gas; a passage
conduit (6) for passage of the gas, fashioned internally of the valve body (2) for
setting the inlet opening (3) in fluid communication with the outlet opening (4);
selector means (7) associated with said valve body (2) and exhibiting at least one
shutter (8) for at least partly interfering in the gas passage conduit (6) and defining
a reduction or interruption of the section for passage of the fluid in said conduit
(6); said valve body (2) comprising at least one sliding channel (9) for the shutter,
said sliding channel being made as a single body with the valve body (2) and in communication
with the gas passage conduit (6), said selector means (7) being coupled to said sliding
channel (9).
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[0001] The object of the present invention is a control device for gas ovens, particularly for gas oven burners.
[0002] As is known, gas ovens are equipped with a thermostat that measures the internal temperature of the oven so as to reduce the flow rate of gas flowing to the burner when the temperature detected reaches a predetermined value.
[0003] As a result, the oxidation-reduction reaction inside the burner takes place with a smaller amount of gas, leading to a decrease in the amount of thermal energy developed and thus to the lowering of the oven temperature.
[0004] In order to realize this process, the ovens of the prior art utilize control units substantially constituted by a plurality of valves and a number of pneumatic circuits.
[0005] These control units also provide for total interruption of the gas flow in the event in which the burner must be turned off, such as in the case of an emergency or malfunctioning of the system.
[0006] In particular, according to a first prior-art technique, in order to ensure the maximum flow rate of the gas, a valve is operatively associated with a conduit having an inlet and an outlet for the combustible gas, whereas the minimum flow rate of the gas is realized by an independent circuit that comprises another valve associated with another conduit having an outlet and an inlet for the gas. In this manner, when the oven is turned on, the valves controlling the maximum and minimum flow rate are open and the gas reaches the burner. When the oven reaches the pre-established temperature, the maximum flow rate valve closes, whereas the minimum flow rate valve remains open. In the event of malfunctioning or significant critical states, the valves shut, stopping delivery of the fluid.
[0007] However, these control systems have a significant drawback originating from the particularly cumbersome and hardly compact structure as it is constituted by a number of structurally independent bodies.
[0008] According to a second prior-art technique, there is comprised a single valve body inside of which the main maximum flow rate conduit and the auxiliary minimum flow rate conduit are afforded.
[0009] The valve body has holes for housing the valves, which are screwed or engaged to the valve body by means of suitable constraining means. Although they are compact in that they are provided with a single body for housing the two conduits, such systems are, in any case, improvable as regards various aspects.
[0010] Firstly, it should be considered that the individual valves (constituted by thermostatic solenoid valves) have a set of components that are individually coupled to the valve body, such as each shutter's sliding seat, which is constituted by a cap found inside the respective seat afforded in the valve body.
[0011] The internal structure of the shutter, comprising movement springs and fluid sealing gaskets, also implies the need for arduous assembly procedures apt for definition of the entire device.
[0012] A further drawback of this prior-art technique consists in the complexity of the valve body in its application inside an oven, which, according to the latest production trends, has increasingly smaller spaces for housing the safety systems.
[0013] In this context, the technical task underlying the present invention is to devise a control device for gas ovens that is capable of resolving the drawbacks cited hereinabove.
[0014] In particular, the aim of the present invention is to realize a control device that is compact, hardly cumbersome and that offers easy maintenance.
[0015] Furthermore, another aim of the present invention is to make available a control device that is structurally simple, with limited costs, and that is versatile and capable of being applied to respective ovens simply and economically.
[0016] The technical task and the specified aim are substantially achieved by a control device for gas ovens that is characterised in that it comprises one or more of the technical solutions claimed herein below.
[0017] By way of approximate and non-limiting example, a description is provided of a preferred, but not exclusive, embodiment of a control device for gas ovens illustrated in the accompanying drawings, of which:
- Figure 1 is a perspective view of the control device for gas ovens according to the present invention;
- Figure 2 is a plan view of the control device appearing in Figure 1;
- Figure 3 is a side elevation of the device of Figure 1; and
- Figure 4 is a sectional view of the device according to the present invention, taken along line III-III of Figure 3.
[0018] With reference to the accompanying figures, a control device for gas ovens is indicated in its entirety by the number 1.
[0019] In particular, the device 1 comprises a valve body 2 having an inlet opening 3 for combustible gas and an outlet opening 4 for combustible gas.
[0020] The valve body 2 is preferably constituted by a main element 5 realized as a monobloc element, having a substantially parallelepiped conformation with a rectangular section. It should be specified that the main element 5 may be of any shape and dimensions, based on various production needs. Purely by way of example and for the sake of simplification, the main element 5 is illustrated in the form of a parallelepiped in the accompanying figures.
[0021] In further detail, the inlet and outlet openings 3, 4 respectively define a seat for connecting users (unillustrated as they are not part of the present invention) to the gas outlet opening 3, and a seat for connecting a delivery line to the gas inlet opening 4. The openings 3, 4 advantageously flank each other and are fashioned on the same surface of the main element 5. As shown in the accompanying figures, the openings 3, 4 are afforded on a smaller lateral face of the above-mentioned main element 5.
[0022] Note that in this manner the position of the openings 3, 4 on the main element 5 defines connection seats parallel to each other and located on one side of the valve body 2.
[0023] As illustrated more clearly in Figure 4, the valve body 2 has an internal passage conduit 6 for passage of the gas and that is apt for setting the inlet opening 3 in fluid communication with the output opening 4.The conduit 6 extends perpendicularly to the inlet and outlet direction of the gas in the respective openings 3, 4.
[0024] The device 1 further comprises selector means 7 associated with the valve body 2 and exhibiting at least one shutter 8 for at least partly interfering in the gas passage conduit 6 and defining a reduction or interruption of the fluid passage section.
[0025] More specifically, the shutter 8 is movable inside a respective sliding channel 9 so as to occlude the passage conduit 6 at least partially. Advantageously, the sliding channel 9 is made as a single body with the valve body 2 and is set in fluid communication with the gas passage conduit 6.
[0026] In this situation, it should be noted that the selector means 7 is directly coupled to the sliding channel 9.
[0027] In accordance with current regulations requiring maximum safety in combustible gas control devices, two shutters 8 suitable for occluding the conduit 6 are provided and in the conduit 6, each shutter 8 is slidably housed in a respective channel 9. The presence of the two shutters 8 thus ensures proper functioning of the device even in the case of malfunctioning of one of the movement systems of the shutter 8.
[0028] In further detail, each sliding channel 9 is defined by a tubular projection 10 extending from a lateral surface of the main element 5.In the example embodiment illustrated in the accompanying figures, the tubular projections 10 emerge from adjacent lateral surfaces of the main element 5 and in particular from a larger lateral surface and from a smaller lateral surface. In this case as well, the tubular projection 10, and thus the sliding channel 9 of the shutter 8, may be positioned in any manner, based on various production and utilisation needs.
[0029] Note that the main element 5 and the tubular projections 10 are advantageously made as a single piece and thus define a single body that can be obtained by means of suitable moulding procedures.
[0030] It should also be noted from the sectional view in Figure 4 that each channel 9 is in communication with the passage conduit 6 at a respective opening 3, 4 so as to intervene with the shutters 8 in different positions with respect to each other and near the gas inlet or outlet.
[0031] The selector means 7 comprises a pair of valves 11, each of which is fitted about a respective tubular projection 10.
[0032] In particular, the valves 11 are solenoid valves commanded by a thermostat, which is not illustrated as it is of a known type and not part of the present invention.
[0033] Each valve 11 exhibits a solenoid group 12 having a substantially cylindrical conformation and that is designed to be fitted about a respective tubular projection 10.
[0034] Each solenoid group 12 is preferably square in section and internally has the solenoid (unillustrated in the accompanying figures as it is of a known type) that is active by magnetic effect on the respective shutter 8. Additionally, the respective electrical connectors 13 extend from the solenoid group 12, for electrical connection with the above-mentioned thermostat.
[0035] Each valve 11 further comprises a closing element 14 associated internally of the solenoid group 12 and developing along the longitudinal development of the respective tubular projection 10.
[0036] More specifically, again referring to the sectional view of Figure 4, each closing element 14 has a substantially cylindrical conformation and is provided with a smaller-section portion 15 that is insertable by mechanical interference internally of the channel 9 defined by the tubular projection 10.
[0037] In other words, the smaller-section portion 15 is snap-fit inside the channel 9 so as to couple the element 14 stably onto the tubular projection 10.This mechanical jointing is implemented by suitably dimensioning the section of the portion 15 with the lune of the passage of the channel 9.
[0038] Note also that the closing element 14 is stably engageable to the solenoid group 12 so as to anchor this solenoid group 12 to the tubular projection 10 as well. The coupling between the closing element 14 and the group 12 preferably takes place by means of the interposition of an elastic sealing ring 16, such as a Seeger ring.
[0039] Each valve 11 further comprises movement means 17 for moving the shutter 8, arranged internally of the tubular projection 10 and interposed between the closing element 14 and the shutter 8.
[0040] In further detail, the movement means 17 is constituted by a spring 18 having a first end 18a that is at least partly housed in a cavity 15a fashioned in the cap 14, and a second end 18b that is opposite the first end 18a and at least partly housed in a cavity 8a fashioned in the shutter 8.
[0041] The cavity 15a is preferably fashioned on the smaller-section portion 15 of the closing element 14.Furthermore, the two cavities 15a and 8a prove to face each other so as to contain the above-mentioned spring 18.
[0042] Note that in this situation the shutter 8 comprises a cursor 19 that has a substantially cylindrical conformation and exhibits a first end 19a in which said cavity 8a for containing the second end 18b of the spring 18 is housed, and a second end 19a apt for interfering internally of the passage conduit 6.
[0043] The second end 19b of the cursor 19 comprises a seal 20 coupled by mechanical jointing to the second end 19b.
[0044] Note that both cursors 19 are slidable inside the channel 9 between two extreme positions corresponding to the open or closed operating configuration. In particular, when the cursor 19 is completely close to the closing element 14 (by effect of the magnetic action implemented by the solenoid group 12), the respective second end 19b equipped with the seal 20 proves to be moved away from the channel 6 so as to enable passage of fluid in the conduit.
[0045] However, when the cursor 19 is moved away from the closing element 14 (by effect of the elastic action of the spring 18), the respective second end 19b equipped with the seal 20 proves to be arranged in the passage section of the conduit 6 so as to occlude the conduit 6 and prevent the passage of fluid. Between the two extreme conditions (totally open or totally closed) of the cursor 19, a plurality of intermediate conditions can be implemented, representing partial blockage of the conduit 6 and defining a limitation of the passage of gas.
[0046] These intermediate conditions can thus define a minimum gas flow rate inside the conduit 6, whereas the open configuration of the cursor 19 (position of the cursor 19 is close to the closing element 14) defines the maximum gas flow rate.
[0047] Advantageously, the device 1 further comprises a plurality of a plurality of fastening protuberances 21 emerging from the main element 5 and made as a single piece with the element 5 so as to be engageable to a structure of the gas oven.
[0048] As illustrated more clearly in Figures 1 and 2, the fastening protuberances 21 are constituted by elastic tabs 22 apt for defining a snap attachment with the supporting frame of the oven in which the device 1 is engaged. Note that the control device 1 for gas ovens according to the present invention enables the aims stated hereinabove to be achieved.
[0049] In fact, owing to the monobloc structure of the valve body 2, and particularly the realization of the main element 5 as a single piece with the tubular projections 10 and with the fastening protuberances 21, it defines a very compact structure that is hardly cumbersome and thus easy and economical to realize.
[0050] Note for example that there is no need to add further elements to the main body 5, such as elements apt for housing the valve cursor 8.
[0051] The coupling of the valve 11 to the tubular element 10 (and thus to the entire monobloc structure of the valve body 2) also takes place by simple mechanical jointing implemented by the closing element 14.As a result, there is no need to provide additional engagement elements or special machining such as thread-forming to facilitate coupling between the valve and the body.
1. A control device for a gas oven, comprising:
a valve body (2) exhibiting an inlet opening (3) for combustible gas and an outlet opening (4) of combustible gas;
a passage conduit (6) of the gas, fashioned internally of the valve body (2) for placing the inlet opening (3) in fluid communication with the outlet opening (4); and
selector means (7) associated to said valve body (2) and exhibiting at least a shutter (8) for at least partly interfering in the gas passage conduit (6), defining a reduction or interruption of the fluid passage section in said conduit (6);
characterised in that said valve body (2) comprises at least a sliding channel (9) of the shutter, made in a single body with the valve body (2) and in communication with the gas passage conduit (6), said selector means (7) being coupled to said sliding channel (9).
2. The device according to the preceding claim, characterised in that the valve body (2) comprises a main element (5) having a substantially parallelepiped
conformation with a rectangular section; said sliding channel (9) exhibiting a tubular
projection (10) extending from a lateral surface of said main element (5).
3. The device according to the preceding claim, characterised in that it comprises at least two sliding channels (9), each of which is defined by a tubular
projection (10) extending from a respective lateral surface of the main element (5).
4. The device according to the preceding claim, characterised in that each channel (9) is in communication with the passage conduit (6) at a respective
opening (3, 4).
5. The device according any one of claims from 2 to 4, characterised in that said selector means (7) comprises at least a valve (11) splined about a respective
tubular projection (10).
6. The device according to the preceding claim, characterised in that said selector means (7) comprises two valves (11), each of which exhibiting:
a solenoid group (12) having a substantially cylindrical conformation and
splined about the respective tubular projection (10);
a closing element (14) associated internally of the solenoid group (12) and
developing along the longitudinal development of the respective tubular projection (10) for closing the inlet to said channel (9); and
movement means (17) of the shutter (8), arranged internally of the tubular projection (10) and interposed between the closing element (14) and the shutter (8).
7. The device according to the preceding claim, characterised in that said movement means (17) of the shutter comprises a spring (18) having a first end
(18a) at least partly housed in a cavity (15a) fashioned in the closing element (14)
and a second end (18b) opposite the first end (18a) which second end (18b) is at least
partly housed in a cavity (8a) fashioned in the shutter (8).
8. The device according to the preceding claim, characterised in that said shutter (8) comprises a cursor (19) having a substantially cylindrical conformation
and exhibiting a first end (19a) in which said cavity (8a) of the second end (18b)
of the spring (18) is housed, and a second end (19b) for interfering internally of
the passage conduit (6).
9. The device according to the preceding claim, characterised in that said second end (19b) of the cursor (19) comprises a seal (20) coupled by mechanical
jointing to the second end (19b).
10. The device according to any one of claims from 6 to 9, characterised in that said closing element (14) exhibits a smaller-section portion (15) insertable by mechanical
interference internally of the channel (9) defined by the tubular projection (10).
11. The device according to any one of claims from 2 to 10, characterised in that said openings (3, 4) respectively define a seating for attaching users to the gas
outlet opening (4), and a seating for attaching a delivery to the inlet opening (3)
of the gas; said inlet and outlet openings (3, 4) being flanked to one another and
fashioned on the same surface of the main element (5) so as to define attaching seatings
that are parallel to one another.
12. The device according to any one of claims from 2 to 11, characterised in that it further comprises a plurality of fixing protuberances (21) emerging from the main
element (5) and made in a single piece with said element (5) so as to be engageable
to a structure of the gas oven.
13. The device of claim 5 or 6, characterised in that the valves (11) are solenoid valves commanded by a thermostat.