Safety switch
AssigneeRockwell Automation Technologies, Inc.
InventorDavid Howard Kerr
Life of this patent
Estimating the term…
Abstract
A safety switch that includes a locking mechanism having a rod locking element that is located adjacent to a rod and engageable with the rod to lock the rod in position relative to a housing. The safety switch locking mechanism includes a locking member that is moveable relative to the housing in response to a difference in inertia between the locking member and the housing when a force is applied to the housing. The locking member is arranged to inhibit disengagement of the rod-locking element from the rod when the force is applied to the housing.
Claims20
A safety switch, comprising:
- a housing;
- a set of electrical contacts located within the housing;
- a rod, axially moveable within the housing to open and close the set of contacts;
- a locking mechanism arranged to lock the rod in position relative to the housing, the locking mechanism comprising a rod locking element located adjacent to the rod and engageable with the rod to lock it in position relative to the housing;
- a solenoid fixed in position relative to the housing;
- a solenoid plunger slideably mounted in the solenoid, the solenoid plunger being connected to the rod locking element, and being arranged such that moving the solenoid plunger relative to the solenoid actuates the rod locking element;
- and
- a locking member that is moveable relative to the housing in response to a difference in inertia between the locking member and the housing when a force is applied to the housing, the locking member being arranged to inhibit disengagement of the rod locking element from the rod when the force is applied to the housing.
The safety switch as claimed in claim i 1 further comprising a rotatable cam arrangement located within the housing, rotation of the cam being arranged to cause axial movement of the rod to open and close the set of electrical contacts.
A safety switch assembly comprising:
- a housing;
- a solenoid having a plunger disposed within the housing;
- a movable rod disposed within the housing and oriented in a generally parallel alignment with the plunger;
- a first locking member moveably disposed between the plunger and the moveable rod;
- and
- a second locking member moveably supported relative to the housing and configured to engage the first locking member to prevent movement of the first locking member with respect to an impact to the housing.
A method of providing a safety switch comprising:
- forming a housing;
- positioning a movable rod in the housing;
- positioning a rod-locking member to selectively engage the movable rod such that the rod-locking member interferes with movement of the movable rod;
- connecting the rod locking member to a cam with a connecting member;
- providing a solenoid to facilitate movement of the cam;
- and
- providing a locking member which selectively interferes with the connecting member to prevent movement of the connecting member associated with impact loading of the safety switch.
Dependencies are inferred from the claim text.