Excavator Coupler Options

Excavator Coupler Options

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Neil from Messick's here, we always try to take an opportunity when we have unique things come through our lot and show them to you. Today we have a customer setting up his excavator using a pin grabber coupler. I'm going to show you the pin grabber, exactly how it works and also the traditional mechanical coupler as well. And show you some of the two pros and cons of the different coupler systems that you can have between your buckets and your excavators. So the coupler that you'll typically find on most excavators is a traditional mechanical coupler.

In this case this is Kubota K-7870 coupler right here, that's used on all the mid-size excavators. The unique thing about this coupler is the way that it interfaces with the bucket. There's always a bit of a race between different excavator manufacturers in order to have the highest bucket breakout force as possible. Typically those measurements are done with a bucket that does not have any kind of quick coupling system on it. That's pinned directly to the excavator boom. It's a bit of a mess in that nobody usually buys their excavators that way. Typically there's some kind of quick-release system involved in order to swap your buckets very easily.

In the case of Kubota's machines, they actually build a quick coupler that pivots and rotates around exactly the same points as what their pintle and buckets do. So there's no loss in bucket breakout force when you decide to put that quick coupler in there. That's very different than say Bobcats or Deers or some competitive manufacturers whose coupler systems typically add a little bit of distance between the excavator boom and the bucket itself robbing your breakout force. So you've got to watch when you put those couplers on oftentimes your machines performance is not as high as what it actually says in the specs sheet.

In the case of this mechanical coupler here, to pull this thing on and off there's a pin here on the backside of the bucket that I pull and then this piece will roll out and slide away from the bucket. Another thing to point out is that the buckets and coupler systems for most excavators aren't actually made by the company that produces the machine. There are bucket fabrication houses that most of these companies sub out to in order to make their buckets and couplers. In Kubota's case they use Werk-Brau in order to manufacture these buckets and in our case we actually combine direct from Werk-Brau as well.

The nice thing about that is that when we need unique buckets for unique applications, it's very easy for us to call them up and get a great bucket with some weird geometry on it. We can price shop those buckets as well and Kubota does do a good job of pricing their buckets really aggressively. We can buy them cheaper direct from the manufacturer than we are from getting them from Kubota. So that's a nice thing. Another thing that you'll see with these things as well if you get one of these quick couplers, the ear portion here on the backside of the bucket can be bought separately.

If you're coming over from a competitive manufacturer and you'll already have buckets, you can buy a set of these blanks and then cut them to match the profile of your bucket and weld them on to bring over your investment in buckets on other brands over onto your Kubota machine. This Werk-Brau coupler here is one of the beneficiaries of this relationship that we have with this company. So this is actually going out to a customer that owns a competitive machine that's switching over to Kubota and this type of coupler here is called a pin grabber.

These are fairly common on really large excavators, big machines where you got so much capacity, you're not worried about bucket break out quite as much. But you can see what happens here in this coupler style. So this is going to go into or Kubota dipper up here at the top and you could see the added distance that's added here between where the boom is going to rest and the bucket is going to attach. This six or eight inches or so is going to cause you to drop your bucket breakout force quite significantly. Now one of the benefits of this is that this is a pin grabber type coupler that's very flexible and can grab a whole lot of different types of buckets by looping into there pins.

So it's nice in that you can find a lot of different buckets that are going to meet to this coupler very very easily and make that transition from one brand to another a lot more painless than what it needs to be. The buckets you can see right over here, these are some big Werk-Brau buckets that the customer needed for this kind of unique application. You can see in the pins right here and how that coupler system is going to work so the pin grabber is typically going to grab the large pin itself and then slide back mechanically or hydraulically on the inside in order to capture the other.

So pin grabber couplers can be either hydraulic which you can operate from the cab which is really convenient or mechanical which is a lot easier to put on the machine because you don't need that extra hydraulic function out on the boom. One way or the other, they're all going to do what they say they do right, they're gonna grab the pins here across these holes, and so one side typically is going to grab the back, the other one is going to come in behind it and then slide forward. The nice part of that sliding mechanism is that if you have buckets with different pin spacing on them.

In this case, these are set up for Caterpillar machines. They're going to be able to come out and grab those pins appropriately and secure the bucket onto the dipper. So that pin grabber coupler is a lot more flexible than what the proprietary one is. Even though you're giving up that bit of digging force. So that's a little bit about mechanical and pin grabber type couplers. If you're in a construction application and you're shopping for a machine, give us a call at Messick's and talk with one of our construction equipment specialists.