The other pattern breaker archetype is being renamed the Brutal Disruptor.

Pattern Breaker
Breaks and disables patterns.

Disable Lock: 2nd level. Gains ability to disable a lock akin to knock spell. ML + 10 vs DC of the lock. Replaces 2nd level insight. Counts as insight for the purposes of prerequisites.

Sunder Pattern: 2nd level. Gains +1 bonus on Sunder per 2 class levels. Replaces Hidden Pattern.

Disable Weapon or Armor: 6th level. Temporarily suppress the magical qualities of a weapon or armor (1 per use). Still functions as masterwork. ML check against 11 + ML of item. Lasts rounds equal to Int modifier. Can have multiple affected items at a time. Replaces swift trapper.

Disabling Aura: Expend psionic focus as full round action to suppress only harmful effects around the pattern breaker 5 ft. aura for Int modifier in rounds. Like null psionics field, but only stops harmful effects. This includes suppressing magical / psionic weapons being used in attacks against the pattern breaker. The pattern breaker does not need to be aware of the effect to be suppressed. Replaces 16th level insight.

Is Disable weapon or armor at-will?

This is very interesting. Two concerns:

1. I like Disable Weapon or Armor, but I usually don't have the ML/CL of the magical weapons of my player's and NPC's items on-hand during a game. Maybe give it a higher DC and use the wielder's save? Just an idea.

2. In general, I find sunder to be a highly underwhelming ability. Do you use it more often in your games?

I guess that sunder fits the style, while being not as useful, while Disable Weapon or Armor is really useful. Maybe even to much so.
If you would need a touch attack (as a standard action) to disable a weapon or armor or if Disable Weapon or Armor had an number of uses per day I think it would be more in line.

Touch attack to disable weapon / armor seems reasonable to me.

And Calain has it right - it's the thematic aspect more than how often it gets used.

And the problem with making it a DC / save based is that low-power items would therefore get the same save as high-power items. For example, a +1 sword vs a +10 sword would effectively have the same chance of being disabled.

For weapons and armor, the CL is simply "enhancement bonus x3"