The present invention relates to a push-in emergency stop cover and, in particular, to a push-in emergency stop cover with a plug-in unit.
An emergency stop cover with plug-in unit includes a lock cover and lock, a lock base having a lockstitch, a stop button, a locking tongue in front end of the lock inserted into a lockstitch for connecting the lock cover to the lock base when the emergency stop cover is in its locked position. Because plug-in units are not available for existing emergency stop covers, users of stop covers need another locking means to ensure that the emergency stop button will not open when the stop button is depressed.
In addition, many existing emergency stop buttons have a locking tongue in the front end of a shutter that projects out through the stop button. The stop cover opens by directly pushing the shutter at the time when it is not locked with a lock. As such, existing emergency stop covers are not convenient and safe to use.
To overcome existing shortcomings, the present invention provides a practical and novel emergency stop cover which utilizes a single key (a push-in unit) which prevents the cover from opening when the key is removed after the emergency stop cover is depressed. The stop cover will only open when the key is inserted through an opening in the stop cover. In addition, the lock base has a lock opening for receiving a simple padlock without removal of the key and plug-in unit.
For the purpose of a preferred embodiment of the invention, this practical, distinctive and novel approach includes a retainer cover, an emergency stop button, a lock cover, a lock base, a lock piece, and a lock spring assembled in the lock cover together with the plug-in unit, slide blocks, a push button and associated springs; the slide blocks and springs are located in a groove of the lock cover. A shank portion or key of the plug-in unit extends through a hole provided in the stop button and into slide blocks to move them backwards. The push button has an integral push rod and the lock has a raised block portion with an inclined plane at the rear of lock.
The slide blocks are moved backwards by the shank or key of the plug-in unit when it is inserted in the stop button and the button is depressed manually. The push rod is pushed inwardly and passes between the slide blocks. The key of the plug-in unit has an inclined plane that propels the raised block at the rear of lock piece to cause the lock piece to move backwards. This action separates a locking tongue from a lockstitch of the lock base so that the lock cover opens. When the key is removed after the emergency stop cover is secured, the slide blocks return to their previous position under pressure of return springs. The locking tongue is prevented from moving backwards which if permitted would open the lock cover. As such, the lock cover is now secured to the lock base.
This practical and novel approach may use a one-piece or two-piece slide block. The user does not need another lock for this practical and novel approach. It has the advantage of operating conveniently, providing safety and reliability. The retainer cover can be rotated manually or machine operable, to cover the opening in the stop button that receives the key to prevent foreign objects from falling into the opening when the key is removed.
The invention will be more readily understood by reference to the accompanying drawings wherein like reference numerals indicate like elements, and wherein reference numerals sharing the same last two digits identify similar corresponding elements throughout the various disclosed embodiments, and in which:
The exploded view of
Returning to
When plug-in unit 2 is removed from the slide blocks 13, the blocks close under spring pressure 12 as shown in
As best shown in
As further illustrated, retainer cover 1 is provided to cover hole c so that foreign matter is prevented from falling into the hole when key b is removed. A stub a on retainer cover 1 is also provided which cooperates with recessed slot d on the edge of stop button 3 to achieve the goal of locking retainer 1 in place.
The invention has been described in detail with reference to particular embodiments thereof, but it will be understood that various other modifications can be effected within the spirit and scope of this invention.
Number | Name | Date | Kind |
---|---|---|---|
4915638 | Domian | Apr 1990 | A |
4970349 | Jones | Nov 1990 | A |
4979634 | Begley | Dec 1990 | A |
5040995 | Graninger et al. | Aug 1991 | A |
5243135 | Shotey | Sep 1993 | A |
5280135 | Berlin et al. | Jan 1994 | A |
5389740 | Austin | Feb 1995 | A |
6198046 | Moodie | Mar 2001 | B1 |
6444906 | Lewis | Sep 2002 | B1 |
6457843 | Kester et al. | Oct 2002 | B1 |
6519208 | DeVries | Feb 2003 | B2 |
6649838 | Lopez, Sr. et al. | Nov 2003 | B1 |
6730845 | Criniti et al. | May 2004 | B1 |
6737576 | Dinh | May 2004 | B1 |
7553040 | Boothe et al. | Jun 2009 | B2 |
7732709 | Puri et al. | Jun 2010 | B2 |
7820910 | Cleghorn et al. | Oct 2010 | B1 |
Number | Date | Country | |
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20090126430 A1 | May 2009 | US |
Number | Date | Country | |
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60989168 | Nov 2007 | US |