NZ233302A

NZ233302A - Quick hitch lock mechanism for excavator bucket

Info

Publication number: NZ233302A
Application number: NZ23330290A
Authority: NZ
Inventors: Paul Owen Jones
Original assignee: Calvert Leonard Graham Substit
Priority date: 1990-04-11
Filing date: 1990-04-11
Publication date: 1994-05-26

Description

<div class="application article clearfix" id="description"> 23 3 3 No: 233302 Date: 11 April 1990 NEW ZEALAND Patents Act 1953 COMPLETE SPECIFICATION IMPROVED LOCKING MECHANISM FOR EXCAVATOR QUICK HITCH I, LEONARD GRAHAM CALVERT, a New Zealand citizen of Hautere Crossroads, RD 1, Otaki, New Zealand, do hereby declare the invention, for which I pray that a Patent may be granted to me, and the method by which it is to be performed to be particularly described in and by the following statement:- -1 2 233302 The present invention relates to an improved locking mechanism for excavator quick hitches, which are used for changing excavator buckets and implements. The improved locking mechanism provides a very effective way of locking a quick hitch to an excavator bucket or implement, by use of a sliding plate wedging member which is wedged underneath at least one of the two bucket, or implement pins, rendering a positive locking mechanism which securely and safely couples the quick hitch with the bucket or implement being used. Previous locking mechanisms for excavator quick hitches, include pivotally mounted jaws, which partly or completely enclose bucket or implement pins in at least one recess to allow secure locking of a quick hitch to an excavator bucket or implement. Methods of biasing the part or complete enclosure of excavator bucket pins, by a pivotally mounted jaw, include cams, hydraulic cylinders, and springs. A disadvantage of a pivotally mounted jaw for' enclosing excavator bucket or implement pins, is that small amounts of movement produced through wear of pivotal joints and or biasing mechanisms result in unacceptable movement and ill fitting of quick hitch to the excavator * ,/V 23 3 3C 3 bucket or implements. Small amounts of movement or ill fitting of the quick hitch to the excavator bucket or implement result in repetitive impulse and shock loadings within various joints and components rendering excess wear, fatigue and possible failure of the quick hitch. The object of the present invention, is to provide a locking mechanism which will reduce substantially the possibility of movement, or ill fitting of quick hitches to excavator buckets or implements. Broadly the invention in one aspect consists of a lock mechanism for excavator quick hitches comprising a sliding plate wedging member which has bi-directional movement towards and away from at least one recess allowing an excavator bucket or implement pin to be securely wedged in said one recess by the sliding plate wedging member and thus lock the quick hitch to the excavator bucket or implement pin; and moving means m coupled to the sliding plate wedging member and operable to provide the bi-directional movement of the sliding plate wedging member toward and away from the recess and bucket or implement pin said moving means includes a thread operated mechanism or a compression spring to move the wedging member toward the recess or a cam ttto c N ■' provide the bi-directional movement. ' '^13 FEB 1994 % 4 233302 One preferred form of the invention, will now be described with reference to the accompanying drawings in which:- Figure 1 is a side view of the quick hitch with improved locking mechanism included. The improved locking mechanism for excavator quick hitches comprises a sliding plate wedging member (1), which is located between an upper block member (3), and a lower plate member (4), all of which are mounted with the body (1) of the quick hitch. The said body (1) contains first and second recesses (5) and (6) respectively, with at least the said second recess (6) being partly closable by the said sliding plate wedging member (2). Various means of providing bi-directional movement to the said sliding plate wedging member (2) can be employed. In Figure 1 an externally threaded member (7), which is located in front plate (12), is threaded into a corresponding internally threaded member (8) which is fixed to the sliding plate wedging member (2). Rotation of the said externally threaded member (7), enables partial closure and complete opening of the said second recess (6), allowing connection and disconnection of the said body (1), with the bucket pin (9). 7 5 23 3 3 Other means of providing the bi-directional movement of the wedging member (2) are an hydraulic cylinder, a compression spring to provide movement toward the second recess (6), a tension spring to provide movement away from the second recess (6) or a cam arrangement. The said second recess (6) is shaped so as to allow a variation in excavator bucket or implement pin centres to be accommodated easily without inhibiting the safe functioning of the locking mechanism. Due to the bevelled end (10), of the said sliding plate wedging member (2), a wedging effect is implemented upon the rotation, and subsequent tightening of the said externally threaded member (7) toward the said second recess member (6) and said bucket pin (9), at the same time forcing first recess (5) firmly against bucket pin (14). A hexagonal shaped head (11), shall be connected to the said externally threaded member (7) to allow a suitable socket to be improvised for rotation of the said externally threaded member (7). A protective sleeve (13) shall also be fixed to the said front plate (12) to enclose and protect the said , v \ 7s»ayi> 6 23 3 3 external and internal threaded members (7) and (8) respectively from foreign matter and debris. > //v i ^ay,^ </div>

Claims

<div class="application article clearfix printTableText" id="claims"> 23 3 3 02 7 WHAT I CLAIM IS:

1. A lock mechanism for excavator quick hitches comprising a sliding plate wedging member which has bidirectional movement towards and away from at least one recess allowing an excavator bucket or implement pin to be securely wedged in said one recess by the sliding plate wedging member and thus lock the quick hitch to the excavator bucket or implement pin; and moving means coupled to the sliding plate wedging member and operable to provide the bi-directional movement of the sliding plate wedging member toward and away from the recess and bucket or implement pin, said moving means includes a thread operated mechanism or a compression spring to move the wedging member toward the recess or a cam to provide the bi-directional movement.

2. A locking mechanism for excavator quick hitches as in Claim 1 wherein the moving means comprises a tension spring to provide movement of the sliding plate wedging member away from the recess.

3. A locking mechanism for excavator quick hitches substantially as described and as illustrated in th$. accompanying drawing. T^FcB 1094 LEONARD GRAHAM CALVERT By his Attorney Don Hopkins & Associates </div>