The present invention is directed to a safety mechanism or device for an accessible chamber closable by a door, particularly for an oven or a cooking device. The door for the accessible chamber is movable between an open position, in which access to the chamber is open; a closed position, in which access to the chamber is closed; an unlocked position or condition, in which the closed position is unlocked; and a locked condition or position, in which the closed position is locked. The door can be moved between the locked position and the unlocked position from a device which is operated from the outside of the chamber and has a lever, and a safety device, which can move it into the unlock position, which is operated from inside the chamber.
Various safety devices for doors are known in the prior art. GB 2 154 646 A discloses a safety device or emergency release mechanism for doors of freight containers, transport vehicles and the like. This emergency release mechanism for a door lock enables a person accidentally enclosed in the container or the vehicle to open the container door from the interior. An operating rod rotatable by a lever is disposed on the outside of the door and has ends with cams for engaging and locking in holding means mounted on the door frame, so that the door can be locked from the exterior by rotating the control rod via the lever. When the door is locked, the lever is in a receiving device, which can be unfastened from the inside of the door. In an emergency, therefore, a person can release the receiving device from the door and push it away therefrom, which will lead to a turning of the lever and, thus, the operating rod to release the door. What is a disadvantage about this mechanism, however, is that the door cannot be opened from the inside when the outer lock mechanism is blocked from the inside or when a person is maliciously shut inside the container.
EP 0 959 208 A1 also discloses a safety release mechanism for a door, for example a climatic chamber. This mechanism makes it possible to move a receptacle device for a lever connected to an operating rod from the inside of the door in order to achieve a rotation of the operating rod and, thus, an unlocking of the door. This device or mechanism, however, has the same disadvantage that was present in GB 2 154 646 A, for example the unlocking of the door can be prevented by blocking the lock mechanism from the exterior.
U.S. Pat. No. 6,022,056 discloses an automatic door spring catch drive incorporated in a door frame and used for operating a locking bolt arrangement on a door. The arrangement comprises a spring bolt and a mortise bolt for locking the spring bolt. The drive is constructed so that the two bolts can be successively operated for opening the door. The complicated construction of this device is a disadvantage.
An object of the present invention is to improve the safety mechanism or device for unlocking a door for a walk-in interior chamber, particularly for cooking devices or ovens, which mechanism overcomes the disadvantages of the prior art in a structurally simple way. In particular, a safety mechanism which enables unlocking a door for a walk-in chamber from the inside, even when the lock mechanism operable from the outside has been blocked.
According to the invention, this problem is solved by a sliding bolt, which is biased by a spring to form a spring bolt, which is disposed either on the inside or the outside of the wall of the chamber for the moving door and from the inside or the outside of the chamber at the door opening and may be moved to a locked position in which the spring bolt engages a locking bolt which is operably connected with a lever, which can move the locking bolt between a locked position and an unlocked position. The improvements are that a release device, which is actuated from the interior of the chamber, can be passively or actively moved so as to unlock the door by moving the spring bolt.
It can be provided that the release device is operated mechanically or pneumatically via at least one actuating element, such as a lever, a pull handle, a traction cable, a press-button or a rotary wheel and an element, preferably in the form of a grate or the like, which is disposed particularly at the bottom of the chamber, is movable in at least one direction of space, and is connected to at least one transmission element, for example in the form of a linkage, a fork device, a cam, a cable line, a drive, a guide pulley and the like.
According to another proposed feature of the invention, the release device or triggering mechanism works electromagnetically upon utilization of at least one permanent magnet and at least one electromagnet, wherein the permanent magnet is preferably attached to the spring bolt.
An advantageous embodiment of the invention is characterized by at least one detecting device for detecting the presence of a person in the interior of the chamber, which detection device has the form of a motion sensor, an infrared sensor, a weight sensor—which may be in the form of a strain gauge—, a reed contact or a microswitch, inside the interior of the chamber and the detecting device is respectively connectible to the triggering mechanism.
A development of the inventive safety mechanism is characterized by at least one spring device by means of which a pre-stressed spring bolt forces the door into its unlocked position or locked position when a person is not present in the chamber. Optionally, according to the present invention, the spring bolt is disposed outside the chamber and the release mechanism is disposed at least partially inside the chamber and the spring bolt is connectible to the release mechanism inside the chamber through a wall of the chamber or through the door, particularly via a shaft that is preferably conducted vapor-tight through the wall of the door by means of a radial seal.
It can be inventively provided that the spring bolt is movable with an electric motor, particularly via the shaft.
It is also inventively preferred if an auxiliary energy supply in the form of, for instance, a battery, a rechargeable photovoltaic cell and/or a rechargeable accumulator, is provided with the triggering mechanism.
Over and above this, it is proposed that the spring bolt and the locking bolt are implemented complementary relative to one another in the region of the mutual engagement and particularly comprise correspondingly beveled surfaces.
It can also be provided that an element, such as a lever, is arranged in the interior, particularly the actuating element, is detachable and is fashioned as a tool, particularly for breaking a pane of glass installed in a door or for jimmying the door open.
Finally, an inventive safety mechanism can be characterized by a display unit via which the presence of a person in the interior can be displayed, particularly in the closed position and/or locked position of the door, preferably upon emission of an alarm signal or, in particular, an acoustic and/or optical nature, whereby the display unit is preferably connectible to the sensor, to the triggering mechanism and/or to a regulating and/or control device.
The invention is based on the surprising perception that a safety mechanism can be implemented so that the opening of, particularly, a cooking chamber door is possible proceeding from the interior of the cooking chamber of the cooking device, even when a lock mechanism arranged on the outside of the cooking chamber door is blocked such that it holds the cooking chamber door in a locked position. The spring bolt for engaging the locking mechanism in the locked position can be unlocked by a release device, thus, moving the cooking chamber door into an unlocked position. The device comprises an accessible inner chamber, which is equipped with a safety device according to the invention can thus be safely used in a number of situations, for example, even in penal institutions and the like.
Other advantages and features of the invention will be readily apparent from the following description, the claims and drawings.
a is an enlarged detailed view with portions broken away for purposes of illustration of a third embodiment of the safety device of the present invention with the spring bolt in an unlocked position;
b is an enlarged detailed view with portions broken away for purposes of illustration of a third embodiment of the safety device according to
The principles of the present invention are particularly useful when incorporated in a safety device, generally indicated at 3, for a cooking device or oven, generally indicated at 1. The safety device 3 comprises a sliding bolt which is also part of the lock mechanism and is biased by a spring to form a spring bolt 5 and an operating lever 7 for opening and closing the cooking chamber door 9 from the outside of the cooking chamber or oven. The cooking chamber door 9 shown in the closed position or locked position in a door opening also has an inspection window 11.
As illustrated in
The operation of the first embodiment of the safety device according to the present invention will be now described with reference to
The door 9 can be locked in two ways. On the one hand, the lever 7 can be in an unlocked position while the door is closed. When the door is in the unlocked closed position, the lever 7 and, consequently, the locking bolt 19 can be moved into the locked position so that the bolt 19 comes into engagement with the spring bolt in the locked position and locks the door 9 in a closed position. If, on the other hand, the lever 7 and, consequently, the bolt 19 are already in the locked position when the cooking chamber door 9 closes, the spring bolt 5 will be designed so that it can briefly move out of the locking position shown in
To open the door, the lever 7 must be rotated so that the bolt 19 rotates out of engagement with the spring bolt 5, for example it is moved out of the locked position into an unlocked position. When the bolt 19 is disengaged from the spring bolt 5, the door 9 is unlocked and can be opened into the open position.
According to the invention, after actuating and opening the door 9, the lever 7 is automatically moved back by a spring device (not shown) into a locked position shown in
The door 9 may also be actively opened by a person in the chamber 13 via a release lever 17, which is connected to a shaft 23 extending through a wall 25 of the cooking chamber. The passage for the shaft 23 in the wall 25 is sealed in a vapor-tight manner by a seal 27, such as a radial or motor shaft seal, so that a steamed cooking process can be implemented in the cooking chamber 13 of the cooking device essentially without an escape of steam. As is well known in the art, a seal system (not shown) is provided between the door and the door opening to prevent escape of the steam. A fork device 29 for connecting the shaft 23 to the spring bolt 5 is disposed at the end of the shaft 23 remote from the lever 17. If, when the door 9 is in the locked position, the person in the cooking chamber rotates the lever 17 in a clockwise direction or presses down on the lever 17, as illustrated in
Optionally, the connection between the release lever 17 and the shaft 23 is made releasable and the lever 17 can also be used to break the inspection window 11 of the door 9 or can be used as a tool, such as a crowbar, for jimmying the cooking chamber door open, even if the door is blocked from the exterior by an article of furniture or the like.
A second embodiment of the safety device is generally indicated at 3′ in
A third embodiment of the safety device, generally indicated at 3″ in
Optionally, the door 9 can be unlocked if a person who is shut in the interior of the cooking chamber 13 actuates a switch or the like, which actively influences the current flowing through the electromagnet so that an unlocking of the door 9 occurs. Optionally, also, the door 9 can be passively unlocked by this person. To this end, the electromagnet 41 is connected to a control device (not shown), which is connected to a sensor 50 (see
The sensor 50 or 51 can also activate a display unit when a person is inside the chamber 13 and the door 9 is closed. The display may be an optical display, such as 55 in
In a modification of the embodiment of
A fourth embodiment of the safety device is generally indicated at 3″′ in
The safety device 3″′ is released as follows: If a person is inside the chamber 13, he can release the safety device 3″′ by swinging the lever 17′ into an open position, as indicated by the arrow 45 of
Although various minor modifications may be suggested by those versed in the art, it should be understood that I wish to embody within the scope of the patent granted hereon all such modifications as reasonably and properly come within the scope of my contribution to the art.
Number | Date | Country | Kind |
---|---|---|---|
101 43 640 | Sep 2001 | DE | national |
Number | Name | Date | Kind |
---|---|---|---|
1203394 | Ottinger | Oct 1916 | A |
1578779 | Titus | Mar 1926 | A |
1593372 | Thompson | Jul 1926 | A |
1787296 | Wild | Dec 1930 | A |
1880637 | Wood | Oct 1932 | A |
1908388 | Watson | May 1933 | A |
2003394 | Sell | Jun 1935 | A |
2012732 | Schmidgall | Aug 1935 | A |
2106951 | Hubbell | Feb 1938 | A |
2167594 | Stratman | Jul 1939 | A |
2201444 | Marsh | May 1940 | A |
2510019 | Holland | May 1950 | A |
2726533 | Quinn | Dec 1955 | A |
2746782 | Schamotta | May 1956 | A |
2747906 | Emmert | May 1956 | A |
2762645 | Bordner | Sep 1956 | A |
2765648 | Hatcher | Oct 1956 | A |
2772107 | Youngberg | Nov 1956 | A |
2772110 | Petrochko | Nov 1956 | A |
2830547 | Zieche | Apr 1958 | A |
2956828 | Clark | Oct 1960 | A |
2966864 | Weaver | Jan 1961 | A |
3066964 | Lemaire | Dec 1962 | A |
3161036 | Himes et al. | Dec 1964 | A |
3346288 | Cosentino | Oct 1967 | A |
3449006 | Andrew | Jun 1969 | A |
3765709 | Van Wyck | Oct 1973 | A |
3786657 | Loikitz | Jan 1974 | A |
3934435 | Gresham | Jan 1976 | A |
3936086 | Berkowitz | Feb 1976 | A |
3998483 | Yan | Dec 1976 | A |
4203622 | Cook et al. | May 1980 | A |
4399755 | Wiedmann | Aug 1983 | A |
4439808 | Gillham | Mar 1984 | A |
4480451 | Fujiya | Nov 1984 | A |
4547008 | Takasaki | Oct 1985 | A |
4569546 | Howard et al. | Feb 1986 | A |
4623181 | Geringer et al. | Nov 1986 | A |
4635977 | Yamada | Jan 1987 | A |
4714285 | Langham | Dec 1987 | A |
4741275 | Lewiner et al. | May 1988 | A |
4848812 | Slaughter | Jul 1989 | A |
4904005 | Frolov | Feb 1990 | A |
5280974 | Weintroub | Jan 1994 | A |
5285604 | Carlin | Feb 1994 | A |
5529354 | Studt et al. | Jun 1996 | A |
5542211 | Colombo | Aug 1996 | A |
5556140 | Sakagami | Sep 1996 | A |
5732614 | Oslin | Mar 1998 | A |
5816137 | Gongwer et al. | Oct 1998 | A |
5823026 | Finke | Oct 1998 | A |
5946919 | McKinney et al. | Sep 1999 | A |
6022056 | Cope et al. | Feb 2000 | A |
6121583 | Hansen | Sep 2000 | A |
6167797 | Bollich | Jan 2001 | B1 |
6298603 | Diaz | Oct 2001 | B1 |
6474247 | Thomas | Nov 2002 | B1 |
Number | Date | Country |
---|---|---|
363804 | Sep 1981 | AT |
40 33 840 | Apr 1992 | DE |
0 143 332 | Aug 1988 | EP |
0 323 580 | Jul 1989 | EP |
0 959 208 | Nov 1999 | EP |
720764 | Feb 1953 | GB |
1 141 585 | Jun 1967 | GB |
2 154 646 | Sep 1985 | GB |
2 275 733 | Sep 1994 | GB |
Number | Date | Country | |
---|---|---|---|
20030047949 A1 | Mar 2003 | US |