Quick coupler having spring applied, hydraulically released primary and secondary lock members mounted on same cross shaft

Patent metadata

Field	Value
Publication number	US-9970177-B2
Application number	US-201514702911-A
Country	US
Kind code	B2
Filing date	May 4, 2015
Priority date	May 4, 2015
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

A quick coupler primary lock arrangement includes a fore-and-aft guided wedge arrangement carried by a cross shaft and is biased forwardly to a lock position by a first spring arrangement, and includes a secondary lock arrangement includes a locking pawl arrangement pivotally mounted to the cross shaft and biased, by a second spring arrangement, to a secondary lock position wherein the pawl arrangement includes a surface disposed in a confronting locking disposition relative to an abutment surface of a fixed plate of the coupler to thereby prevent rearward movement of the wedge arrangement from the lock position. A normally depressurized hydraulic cylinder is coupled to the pawl arrangement and when selectively pressurized overcomes spring biasing forces and pivots the pawl arrangement from the secondary locking position and then shifts the wedge arrangement rearward to a coupler release position. An electro-hydraulic control arrangement prevents unintentional operation of the hydraulic cylinder.

First claim

What is claimed is:

1. A quick coupler adapted for coupling a work implement to an arm carried by a work machine, the quick coupler comprising:
a pair of parallel, transversely spaced, vertical side plates each having rear and bottom edges and being joined together by transverse plate having opposite side edges located adjacent said rear and bottom edges of said side plates;
a latch mechanism including a cross shaft extending between, and having opposite ends disposed adjacent to, said vertical side plates at respective locations spaced forward from the rear edges of said vertical side plates, first and second wedge members respectively having forward ends fixed to opposite end regions of said cross shaft, at least one upright latch pivotally mounted to said cross shaft and a hydraulic cylinder having opposite ends respectively pivotally connected to said at least one latch and to said transverse plate;
said pair of vertical side plates respectively including fore-and-aft extending guide slots located beside said first and second wedge members, and said first and second wedge members respectively having first and second wedge sections extending transversely through said first and second guide slots and respectively having first and second forwardly converging wedge surfaces;
a first biasing spring arrangement being disposed for biasing said first and second wedge members forwardly for respectively engaging the first and second wedge sections into locking engagement with respective wedge-shaped recesses in a mounting bracket of a work implement, whereby the first and second wedge members and said first biasing spring arrangement form part of a primary lock securing the quick coupler to the work implement mounting bracket;
said transverse plate being provided with at least a third guide slot, with said third guide slot being oriented in fore-and-aft alignment with, and receiving a lower end region of, said at least one upright latch when said quick coupler is locked in engagement with the work implement bracket, with an end of said third guide slot and an upright rear surface of said at least one latch being disposed in confronting relationship to each other for engaging each other to effect a secondary lock for preventing disengagement of the wedge member wedge sections from the respective wedge-shaped recesses provided in the work implement bracket in the event that insufficient retention force is applied to the wedge members by the first biasing spring arrangement;
a second biasing spring arrangement being coupled to said at least one upright latch and, as viewed looking towards a right end of said cross shaft, tending to bias said at least one latch counterclockwise about said cross shaft, with said at least one latch being provided with a downstop limiting counterclockwise movement of the at least one latch and, hence limiting forward movement of the lower end region of said at least one latch so as to properly dispose the rear surface of the at least one latch for locking engagement with the rear end of the third guide slot; and
the hydraulic cylinder being coupled to said at least one latch at a location below said cross shaft and being selectively pressurized to effect contraction so as to cause said at least one upright latch to pivot clockwise about said cross shaft in opposition to the second biasing spring arrangement with such contraction initially elevating the lower end region of the at least one latch from said third guide slot and then causing the wedge members to move rearwardly when the hydraulic cylinder lies along a line of action passing through the cross shaft, this movement of the wedge members being sufficient for them to be disengaged from the wedge-shaped recesses of the work implement bracket when it is desired to disengage the quick coupler from the working implement.

2. The quick coupler, as defined in claim 1 , further including an upright plate extending transversely between rear regions of said side plates; and said first spring arrangement including first and second coil compression springs respectively compressed between said upright plate and said first and second wedge members.

3. The quick coupler, as defined in claim 2 , and further including first and second spring guide rods respectively received within said first and second coil compression springs, with forward ends of said first and second guide rods respectively being joined to said first and second wedge members.

4. The quick coupler, as defined in claim 1 , wherein said down stop is a roll pin positioned for engaging the transverse plate and bridging said third guide slot when the at least one upright latch is in a position for effecting said secondary lock.

5. The quick coupler, as defined in claim 1 , wherein a second upright latch identical to said at least one upright latch is disposed in parallel relationship to said at least one upright latch and is mounted for pivoting about said cross shaft at a location spaced transversely from said at least one upright latch; and a fourth guide slot being provided in said transverse plate in parallel relationship to said third guide slot and being provided in fore-and-aft alignment with said second upright latch and receiving a lower end region of said second upright latch; and said second spring biasing arrangement acting on said second upright latch and tending to bias the second latch in a counterclockwise pivotal movement about said cross shaft.

6. The quick coupler, as defined in claim 5 , wherein said second spring biasing arrangement is a fore-and-aft extending coil tension spring located between and having a forward end coupled to, an upper region of each of said first and second upright latches which is located at a level above the cross shaft; a fore-and-aft extending mounting bracket having a forward end coupled to said cross shaft and a rear end located behind, and coupled to a rear end of said coil tension spring.

7. The quick coupler, as defined in claim 6 , wherein a transverse spring mounting rod has opposite ends respectively received in first and second transverse holes respectively provided at said upper regions of the first and second upright latches; said spring mounting rod having a groove formed therein at a location between the first and second upright latches; and the forward end of said coil tension spring being defined by a hook received in said groove.

8. The quick coupler, as defined in claim 6 , wherein said mounting bracket is defined by a forwardly opening U-shaped member having first and second, fore-and-aft extending, legs having respective forward ends coupled to opposite end regions of said cross shaft, the legs having rear ends joined by a leg connecting portion; and said rear end of the coil tension spring being defined by a rear hook engaged with said leg connecting portion.

9. The quick coupler, as defined in claim 8 , wherein said forward ends of said legs of the U-shaped member are coupled to said cross shaft by first and second fasteners which extend through said first and second wedge members.

10. The quick coupler, as defined in claim 1 , wherein the hydraulic cylinder includes a piston rod having a forward end pivotally coupled to the at least one latch member and includes a barrel having an end pivotally coupled to the transverse plate.

11. The quick coupler, as defined in claim 5 , wherein the hydraulic cylinder includes a piston rod having a cross tube at its forward end located between the at least one and second latches; a connecting pin extending through said at least one and second latches and said cross tube and pivotally connecting the piston rod to the at least one and second latches; and said hydraulic cylinder including

Assignees

• Deere & Co

Inventors

• Koestler Adam J
• Simmons Jason M
• Sulzer Daniel M
• Nier Mark
• Ott Cory

Classifications

• E02F3/3613

  with means for absorbing any play therebetween (E02F3/364 takes precedence) · CPC title

• E02F3/365

  with redundant latching means, e.g. for safety purposes · CPC title

• Y10T403/591

  having operating mechanism · CPC title

• E02F3/364

  using wedges · CPC title

• E02F3/3609

  of the quick acting type, e.g. controlled from the operator seat (quick-acting couplers to connect booms or arms to tractors E02F3/627; quick-acting couplers for machines mounted on tractor A01B59/06; couplings of the quick-acting type per se F16L37/00) · CPC title