NL1041007B1

NL1041007B1 - Latch apparatus for safety belt.

Info

Publication number: NL1041007B1
Application number: NL1041007A
Authority: NL
Inventors: Huang Chung-Ming; Ouyang Chih-Hung; Lai Deng-Horng; Chien Ke-Cheng; Hung Tzu-Jen
Original assignee: Brogent Tech Inc
Priority date: 2013-10-22
Filing date: 2014-10-21
Publication date: 2016-07-04
Also published as: NL1041007A; CA2868662C; CA2868662A1; TWM473859U

Abstract

A latch apparatus for a safety belt, having a latch plate with a latch hole, the latch apparatus includes: a housing having a safety belt insertion slot; the latch plate through the insertion slot into the housing; a vertical locking disk attached inside the housing with a perimeter having a latch hook, first and second locking portions; the latch hook locked inside the latch hole; a first elastic unit between an eccentric area and the housing; an electromagnetic lock including an electromagnetic member secured onto the housing, a retractable metal shaft into the electromagnetic member and a first latch member connected to the metal shaft and locked onto the first locking portion; a pressing lock comprising a button attached inside the housing and exposed and a second elastic unit between the button and the housing; the button having a second latch member locked onto the second locking portion.

Description

TITLE: Latch apparatus for safety belt

I

FIELD OF THE INVENTION

The present invention is related to a latch apparatus, in particular, to a latch apparatus for a safety belt.

DESCRIPTION OF RELATED ART

Most of us now have the opportunity to enjoy the so called “four-dimensional” (4D) or 4D-above in an advanced sensational experience theater. As the audience views the show on their seats, in order to prevent possible dangers caused by the audience leaving their seats personally during the show randomly, every chair in the theater is equipped with a central control safety belt device. In other words, the lock can only be released solely by the theater control center such that the audience can release the lock on their own. A known safety belt typically comprises a latch apparatus arranged on one side of the chair and a safety belt arranged on another side of the chair. The safety belt is connected to a latch plate, and the latch plate can be inserted into the latch apparatus. The latch apparatus includes a central control lock and a horizontal locking disk arranged therein. The horizontal locking disk is locked onto the latch hole on the latch plate, and the central control lock is moveably locked onto the horizontal locking disk in order to prevent the horizontal locking disk from rotating such that the safety belt cannot be disengaged from the latch apparatus but can be maintained at the locked state. If the locked state of the latch apparatus is to be released, the theater control center can control the latch apparatus to allow the central control locks to be unlocked such that the locked state of the latch apparatus can be released; therefore, the safety belt can be disengaged from the latch apparatus.

Nevertheless, machine or mechanical malfunctions can still occur from time to time. Since the latch apparatus used by the known safety belt devices are controlled by one single central control lock only, once latch apparatus malfunctions, it is not uncommon to find that the safety belt devices are suddenly released during the show, which can cause dangers.

In view of the above, the latch apparatus of the known safety belt device uses the horizontal locking disk; however, despite the fact that the horizontal locking disk can provide the aforementioned function, the structural design of the horizontal locking disk has problems of its own, which can cause central control lock and the latch plate driven thereby to have the drawbacks of complicated and unstable structures.

SUMMARY OF THE INVENTION

An objective of the present invention is to providea latch apparatus for a safety belt capable of utilizing a vertical locking disk and allowing the latch apparatus to be equipped with both an electromagnetic lock (provided for central controls) and a pressing lock such that it is of a simple structure with stabilized effect. In addition, when the electromagnetic lock is unlocked due to malfunctions of the electromagnetic lock, it is still able to utilize the pressing lock to ensure that the latch apparatus is still maintained at the locked state; therefore, the latch apparatus has a dual protection function.

To achieve the aforementioned objective, the present invention provides a latch apparatus for a safety belt, the safety belt having a latch plate connected thereto, the latch plate having a latch hole formed thereon, the latch apparatus comprising: a housing having a safety belt insertion slot formed thereon; the latch plate penetrating through the safety belt insertion slot to be inserted into the housing; a vertical locking disk pivotally attached inside the housing; a perimeter of the vertical locking disk having a latch hook, a first locking portion and a second locking portion formed thereon; the latch hook locked inside the latch hole; a first elastic unit connected between an eccentric area of the vertical locking disk and the housing; an electromagnetic lock comprising an electromagnetic member secured onto the housing, a retractable metal shaft moveably inserted into the electromagnetic member and a first latch member connected to a free end of the metal shaft; the first latch member correspondingly locked onto the first locking portion of the vertical locking disk; and a pressing lock comprising a button slidably attached inside the housing and exposed out of the housing and at least one second elastic unit connected between the button and the housing; the button having a second latch member; the second latch member correspondingly locked onto the second locking portion of the vertical locking disk.

In comparison to the prior art, the present invention has the following advantageous effects: with the use of a vertical locking disk, it is of a simple structure with a stabilized effect; in addition; since the latch apparatus includes both an electromagnetic lock and a pressing lock, the unlocking of any one of two locks alone is insufficient to unlock the latch apparatus from the locked state such that the latch apparatus is able to provide a dual protection function.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing the latch apparatus and the safety belt of the present invention before the locking there between; FIG. 2 is a perspective exploded view of the latch apparatus of the present invention viewed from an angle; FIG. 3 is a perspective exploded view of the latch apparatus of the present invention viewed from another angle; FIG. 4 is a cross sectional view of the present invention according to FIG. 1 after the locking there between; FIG. 5 is a cross sectional view of the present invention according to FIG. 4 after the electromagnetic lock is unlocked; FIG. 6 is a cross sectional view of the pressing lock of the present invention according to FIG. 5 and after the latch apparatus is released from the locked state; and FIG. 7 is a cross sectional view of the present invention according to FIG. 4 in which an unlocker is used for unlocking the electromagnetic lock.

DETAILED DESCRIPTION OF THE INVENTION

The following provides a detailed description of the present invention along with the accompanied drawings; however, it shall be understood that the accompanied drawings are provided for illustrative purposes only, which shall not be treated as limitations of the present invention.

The present invention provides a latch apparatus for a safety belt. As shown in FIG. 1, the safety belt device comprises a safety belt 100 arranged on one side of a chair (not shown in the figure) and a latch apparatus 200 arranged on another side of the chair. The safety belt 100 includes a latch plate 1 connected thereto; the latch plate 1 includes at least one latch hole 11 formed thereon; the following uses the embodiment having two latch holes 11 arranged in parallel with each other as an example for illustration. The latch apparatus 200 comprises a housing 2, at least one vertical locking disk 3, at least one electromagnetic lock 4 and a pressing lock 5. The following uses the embodiment having two vertical locking disks 3 and two electromagnetic locks 4 as an example for illustration. The latch plate 1 of the safety belt 100 can be detachably inserted into and locked inside the latch apparatus 200.

As shown in FIGs 1~4, FIG. 1 is a perspective view showing the latch apparatus and the safety belt before the locking there between; FIGs 2 and 3 are perspective exploded views of the latch apparatus 200 viewed from two different angles; FIG. 4 is a cross sectional view showing the latch apparatus and the safety belt after the locking there between.

The housing 2 includes a top board, a bottom board and a plurality of vertical boards surrounding between the top board and the bottom board without labelled reference numerals. In the two opposite vertical boards of the plurality of vertical boards, one vertical board includes an opening hole 221 and a safety belt insertion slot 211 formed thereon while another vertical board is used for securing two electromagnetic locks 4 thereon. In addition, at least one blocking member 23 and an attachment member 24 are disposed between another two opposite vertical boards of the plurality of vertical boards and a plurality of shafts are cross linked thereto. In this embodiment, as shown in the figure, the housing 2 comprises a base 21 and a cover 22 mounted at an external of the base 21; one end of the base 21 includes a safety belt insertion slot 211 formed thereon; an internal of the base 21 includes a plurality of shafts cross linked thereon. Such shafts comprise an axle shaft 212, a first guiding shaft 213 (see FIGs 2 and 4), two second guiding shafts 214 and a connecting shaft 215. The cover 22includes an opening hole 221 formed on one side corresponding to the side of the base 21 having the safety belt insertion slot 211 formed thereon in order to expose the safety belt insertion slot 211 and a button 51 described in detail in the later content, whereas another side of the cover 22 opposite from the opening hole 221 is formed of an opening. The aforementioned blocking member 23 is of a horizontal beam shape and cross linked between two opposite sides of the base 21. The latch plate 1 of the safety belt 100 passes through the safety insertion slot 211 in order to be inserted into the housing 2.

An axle sleeve (shown without reference numeral) is connected between axial centers of the two vertical locking disks 3 in order to allow the two to be spaced apart from each other and to rotate synchronously, and a channel (shown without reference numeral) is formed between the two vertical locking disks 3. The axle sleeve includes the aforementioned axle shaft 212 penetrated there through in order to pivotally attach the two vertical locking disks 3 between the aforementioned two opposite vertical boards (shown without reference numerals) of the housing 2. In other words, the two vertical locking disks 3 are vertically disposed inside the housing 2. In addition, a first elastic unit 37 is connected between an eccentric area of one of the two vertical locking disks 3 and the aforementioned attachment member 24. In this embodiment, a first elastic unit 37 is connected between the eccentric area of each one of the vertical locking disks 3 and the attachment member 24. Furthermore, as shown in the figure, the two locking disks 3 are pivotally attached between the two opposite sides of the base 21. A perimeter of each one of the vertical locking disks 3 includes a first locking portion 31, a second locking portion 32 and a latch hook 33. In this embodiment, it further includes a protruding portion 34 and a stopping portion 35. Moreover, the latch hook 33 and the stopping portion 35 are formed by a notch 36 configured on the perimeter of the vertical locking disk 3, and the latch hook 33 is located on a path for insertion of the safety belt insertion slot 211 in order to ensure that the latch plate 1 inserted from the safety belt insertion slot 211 can be locked by the latch hook 33. Additionally, each one of the protruding portion 34 generates a rotational path (not shown in the figure but please refer to FIGs 5 and 6) with the rotation of each one of the vertical locking disks 3. Furthermore, the aforementioned blocking member 23 is located on the rotational path of the protruding portion 34 during the rotation driven by unlocking in order to restrict rotational angles of the two vertical locking disks 3. Moreover, since the latch apparatus200 is under the locked state, the two latch hooks 33 are locked inside the two latch holes 11 of the safety belt 100 respectively.

Each one of the electromagnetic locks 4 comprises an electromagnetic member 41 secured onto the housing 2, a retractable metal shaft 42 moveably inserted into the electromagnetic member 41 and a first latch member 43 connected to a free end of the metal shaft 42. In this embodiment, two third elastic units 45 are connected between the aforementioned connecting shaft 215 of the housing 2 and the two metal shafts 42 of the two electromagnetic locks 4; as shown in the figure, each one of the metal shafts 42 (or the first latch member 43) includes a connecting portion 421; the two third elastic units 45 are connected between the connecting shaft 215 an the two connecting portions 421. In addition, each one of the first latch members 43 further includes an elongated first guiding slot 431 formed thereon, and the aforementioned first guiding shaft 213 of the housing 2 is inserted into the first guiding slot 431 in order to guide the metal shaft 42 along with the first latch member 43 on its free end to stably and precisely retract. Accordingly, the two first latch members 43 of the two electromagnetic locks 4 are correspondingly locked onto the two first locking portions 31 of the two vertical locking disks 3 in order to restrict the rotation of the two vertical locking disks 3 and to achieve the object of locking thereof. Furthermore, as shown in the figure, the two electromagnetic members 41 are arranged in parallel with each other and secured on another end of the base 21 (in addition to that the front end of the metal shaft 42 inserted into the electromagnetic member 41 to be locked inside the housing 2, and the electromagnetic member 41 excluding the portion of its front end is exposed to the external of the housing 2) as well as configured to drive the two first latch members 43 to retract inside the housing 2.

The pressing lock 5 comprises a button 51 slidably attached inside the housing 2 and exposed outward from the aforementioned opening 221 and at least one second elastic unit 52 connected between the button 51 and the housing 2. The following uses the embodiment having two second elastic units 52 as an example for illustration, and the button 51 includes a second latch member 512. In this embodiment, the second latch member 512 is a horizontal beam object provided to correspondingly lock onto the two second locking portions 32 of the two vertical locking disks 3 at the same time and configured to restrict the rotations of the two vertical locking disks 3. Secondly, the button 51 includes at least one second guiding slot 513 of an elongated shape formed thereon, and the following uses the embodiment having two second guiding slots 513 as an example for illustration. The aforementioned two guiding shafts 214 of the housing 2 are inserted into the two second guiding slots 513 respectively in order to guide the button 51 to slide back and forth inside the housing 2. Thirdly, each one of the second elastic units 52 is connected between one of the two second guiding shafts 214 and the second latch member 512 of the button 51; in other words, it is connected between one of the second guiding shafts 214 and a connecting portion 5121 of the second latch member 512; wherein the second latch member 512 includes two connecting portions 5121 formed thereon and provided to allow two second elastic units 52 to be connected thereto respectively.

Since the vertical locking disk 3 is vertically disposed inside the housing 2, it facilitates the driving actuation among the latch plate 1, the electromagnetic lock 4 and the pressing lock 5. Therefore, the structure configured among these components can be simple and can even be of the effect of stabilizing the structure.

When the latch apparatus 200 of the present invention is at the locked state, as shown in FIG. 4, and when it is to be unlocked, the electromagnetic lock 4 needs to be activated first via the central control method in order to open up the first lock; following which, a person needs to manually press onto the pressing lock 5 in order to open up the second lock as described in further details below. FIG. 5 is a cross sectional view of the electromagnetic lock 4 after being unlocked. To open up the first lock: when the electromagnetic lock 4 is locked, it only requires the control from the theater (4D or 4D-above advanced sensational experience theater) central control in order to activate the electromagnetic lock 4 of each chair inside the theater altogether uniformly such that the metal shaft 42 of the electromagnetic lock 4 is able to drive the first latch member 43 on its free end to retract, and the first latch member 43 is no longer locked onto the first locking portion 31 of the vertical locking disk 3; therefore, the first lock can be opened. On the contrary, when the activation of the electromagnetic lock 4 is stopped, with the utilization of the elastic recovery forces of the two third elastic units 45, the metal shaft 42 is extended again such that the first latch member 43 is locked onto the first locking portion 31 again. Once the first lock is opened, due to the second lock in which the pressing lock 5 is still locked onto the vertical disk 3, the latch plate 1 of the safety belt 100 is still locked by the latch hook 33; therefore, the latch apparatus 200 of the present invention is still maintained at the locked state. FIG. 6 is a cross sectional view showing the pressing lock 5 is unlocked and the latch apparatus 200 is released from the locked state. When the first lock in which the electromagnetic lock 4 is opened, a person can manually press onto the button 51 of the pressing lock 5 in order to allow the button 51 to slide toward the internal of the housing 2 and the second latch member 512 is disengaged from the second locking portion 32 of the vertical locking disk 3 at the same time such that the second latch member 512 is no longer locked inside the second locking portion 32; therefore, the second lock is opened and the two vertical locking disks 3 are at the state for free rotations. At this time, the two first elastic units 37 originally under the elastically extended state is elastically retracted in order to pull the two vertical locking disks 3 to rotate simultaneously (see FIG. 6) such that the latch hook 33 is no longer locked onto the latch hole 11 of the latch plate 1 but pulls out the latch plate 1 of the safety belt 100. Since the two vertical locking disks 3 are pulled by the two first elastic units 37 to be maintained at the state after their rotations, the first and second latch members 43, 512 are both unable to return to being locked again; under such condition, when the latch plate 1 of the safety belt 100 is inserted into the safety belt insertion slot 211 again, the free end of the latch plate 1 then pushes the stopping portions 35 of the two vertical locking disks 3 such that the two vertical locking disks 3 rotate in a reverse direction to return to their original positions, the latch hook 33 is locked inside the latch hole 11 again and the two first elastic units 37 are elastically extended again. At this time, due to the removal of the pressing force from the pressing lock 5, the button 51 can be pulled back to its original position under the exertion of the elastic recovery forces of the two second elastic units 52 such that the second latch member 512 is locked onto the second locking portion 32 again, and the first latch member 43 of the electromagnetic lock 4 can also be locked onto the first locking portion 31 again via controls.

In brief, after opening up the first lock (see FIG. 5) followed by opening up the second lock (see FIG. 6), the vertical locking disk 3 is no longer restricted such that it is able to rotate with the axle shaft 212 as the rotational axle. At this time, the first elastic unit 37 pulls the vertical locking disk 3 to rotate such that it is no longer locked onto the latch plate 1 in order to allow the safety belt 100 to pull out the latch plate 1 from the safety belt insertion slot 211 in a reverse direction and to unlock the safety belt device (meaning that the locked state between the safety belt 100 and the latch apparatus 200 is released). When the latch plate 1 is inserted into the safety belt insertion slot 211 again, the latch pate 1 then pushes the vertical locking disk 3 to rotate in a reverse direction in order to be locked again, and the first elastic unit 37 returns to the elastically extended state again at the same time. FIG. 7 is a cross sectional view showing the use of an unlocker 6 to unlock the electromagnetic lock 4. During the situation of power shortage or malfunctions of the electromagnetic lock 4 where it cannot be opened, a person can manually use an unlocker 6 to release the electromagnetic lock 4 from the locked state. As shown in the figure, a pushing portion 44 is formed to cross link between the two first latch members 43 of the two electromagnetic locks 4, and the button 51 of the pressing lock 5 includes an unlocking insertion hole 511 formed thereon corresponding to the pushing portion 44. By using an unlocker 6 of, such as, a key to insert into the unlocking insertion hole 511 and to pass through the aforementioned channel (shown without reference numeral) between the two vertical locking disks 3, the free end of the unlocker 6 is able to abut against the pushing portion 44 in order to push the two metal shafts 42 of the two electromagnetic locks 4 to retract such that the two first latch members 43 are disengaged from the two first locking portions 31; therefore, the electromagnetic lock 4 can still allow the first lock to be opened during the power shortage or malfunctions of the electromagnetic lock 4. To be more specific, as shown in FIG. 3 again, each one of the first latch member 43 includes a bracket of a generally L shape (as shown in FIG. 3, there are two brackets of generally L shapes but shown without reference numerals). The two brackets are arranged opposite to each other and parallel with each other in order to form the aforementioned pushing portion 44 in combination; wherein a horizontal portion of each one of the brackets is secured onto the each one of the first latch member 43, and a vertical portion of each one of the brackets is combined to form a vertical shaft and protruding from the two first latch member 43 in order to facilitate the unlocker 6 to abut and to push thereon. In other words, the unlocker 6 abuts and pushes the pushing portion 44, and such pushing portion 44 is formed by two brackets of generally L shapes combined together.

In this embodiment, a hollow column 514 extends from an inner side of the button 51 at a location corresponding to the unlocking insertion hole 511. The hollow column 514 is connected to the unlocking insertion hole 511, and the unlocker 6 passes through the unlocking insertion hole 511 and the hollow column 514 in order to be inserted into the housing 2 such that the unlocker 6 can be ensured to be prevented from being tilted during the insertion therein.

In view of the above, the present invention has the following advantageous effects over the prior art: with the design of the vertical locking disk 3, the vertical locking disk 3 as well as the latch plate 1, the electromagnetic lock 4 and the pressing lock 5 driven by the vertical locking disk 3 can all have simple structure with stabilized effect; furthermore, with the latch apparatus 200 equipped with both the central controlled electromagnetic lock 4 and the manually unlocked pressing lock 5, the latch apparatus 200 requires both the electromagnetic lock 4 and the pressing lock 5 to be unlocked in order to release the latch apparatus 200 from the locked state. In other words, the latch apparatus 200 of the present invention has the dual protection function such that even though a person may open the pressing lock 5 on his or her own, the electromagnetic lock 4 can still be used to keep the safety belt device from being unlocked. In addition, even for the situation where the electromagnetic 4 is mistakenly unlocked due to malfunctions or improper manual operations, the pressing lock 5 can still be used to keep the safety belt from being unlocked. As a result, dangers associated with the audience accidental unlocking the latch apparatus in the theater can be prevented.

Moreover, the present invention further includes the following advantageous effect: during the situation of power shortage or malfunctions of the electromagnetic lock 4 where the electromagnetic lock 4 cannot be unlocked, a person can still use an unlocker 6 to manually unlock the electromagnetic lock 4.

The above provides descriptions on the preferred embodiment of the present invention only, which shall not be treated as limitations of the present invention. Any equivalent modifications without deviating from the spirit of the present invention shall be deemed to be within the scope of the present invention.

Claims

CLAIMS 1. A safety belt locking device, which safety belt has a locking plate attached thereto, which locking plate has a locking hole formed thereon, which locking device comprises: a housing with a safety belt insertion slot formed thereon; the locking plate penetrating through the safety belt insertion slot for insertion into the housing; a vertical slot disk rotatably mounted within the housing; wherein a perimeter of the vertical lock disk formed thereon has a locking hook, a first locking member and a second locking member; wherein the locking hook closes within the locking hole; a first elastic unit connected between an eccentric region of the vertical slot disk and the housing; an electromagnetic closure comprising an electromagnetic member mounted on the housing, a retractable metal shaft movably inserted into the electromagnetic member and a first locking member secured to the free end of the metal shaft; wherein the first locking member engages correspondingly with the first closing portion of the vertical lock disk; and a snap closure that includes a button slidably mounted within the housing and protruding from the housing as well as at least one second elastic unit connected between the button and the housing; wherein the button has a second locking member; wherein the second locking member engages correspondingly with the second closing portion of the vertical lock disk.

A safety belt locking device according to claim 1, wherein a third elastic unit is connected between the metal shaft of the electromagnetic closure and the housing.

A safety belt locking device according to claim 2, wherein the first electromagnetic closure locking member comprises a first guide slot formed thereon; wherein the housing comprises a first guide shaft disposed therein; wherein the first guide slot has the first guide shaft inserted therein for guiding it; wherein the button of the snap closure includes at least one second guide slot formed thereon; wherein the housing comprises at least one second guide shaft; wherein the at least one second guide slot has the at least one guide shaft inserted therein for guiding it.

A safety belt locking device according to claim 3, wherein the second elastic unit of the snap closure is attached between the at least one second guide shaft and the second locking member.

The safety belt locking device of claim 4, wherein the perimeter of the vertical lock disk further comprises a protruding portion formed thereon; wherein the protruding portion generates a rotation path with a rotation of the vertical slot disk; wherein the housing comprises a blocking member formed thereon; the blocking member engaging the rotation path of the projecting portion for blocking it.

A safety belt locking device according to claim 5, further comprising a release means; a release / insertion hole formed on the button of the snap closure; wherein the valve is inserted into the housing through the valve insertion hole and pushes the metal shaft of the electromagnetic closure to retract.

The safety belt locking device according to claim 1, further comprising another vertical lock disc identical to the vertical lock disc and another electromagnetic closure identical to the electromagnetic closure; wherein the two vertical slot disks are spatially spaced apart and rotatably mounted within the housing and configured to rotate synchronously; the two electromagnetic members of the two electromagnetic closures being arranged parallel to each other and mounted on the housing; the two first locking members of the two electromagnetic closures engaging correspondingly on the two first closure members of the two vertical lock disks; the two locking hooks of the two vertical lock disks engaging the two locking holes of the locking plates, respectively.

A safety belt locking device according to claim 7, wherein another first elastic unit identical to the first elastic unit is connected between an eccentric region of the other vertical lock disk and the housing; and wherein a third elastic unit is connected between the two metal shafts of the two electromagnetic closures and the housing, respectively.

A safety belt locking device according to claim 8, wherein the two first locking members of the two electromagnetic closures, respectively, comprise a first guide slot formed thereon; wherein the housing comprises a first guide slot; the two first guide slots having the first guide shaft inserted therein to guide it; wherein the button of the snap closure includes at least one second guide slot formed thereon; wherein the housing comprises and at least one second guide shaft; wherein the at least one second guide slot has the at least one second guide shaft inserted therein for guiding it.

The safety belt locking device of claim 9, wherein the at least one second elastic unit of the snap closure is of a configuration of two; wherein each second elastic unit is connected between the at least one second guide shaft and a portion of the second closure member.

The safety belt locking device of claim 10, wherein a perimeter of each vertical slot disk further comprises a protruding portion; wherein each projecting portion generates a rotation path with a rotation of the vertical slot disk; wherein the housing comprises a blocking member; the blocking member engaging the two rotation paths of the two projecting portions for blocking them.

A safety belt locking device according to claim 11, further comprising a release means; a release / insertion hole formed between the snap closure and the key; a channel formed between the two vertical lock disks; wherein the valve is inserted into the housing through the valve insertion hole and synchronously pushes the two metal shafts of the two electromagnetic closures to retract through the channel formed between the two vertical lock disks.

A safety belt locking device according to claim 12, wherein a push member is formed between the two first locking members of the two electromagnetic closures; wherein the valve presses against the push member to allow the two metal shafts to retract.