9 the shovel arm assembly c comprises a rigid beam 32 having an upper end which is pivotally connected to the common point z and one end of the shovel arm cylinder d is pivotally connected to the same point x on the frame 20 whereat the stroke arm a is connected the stroke arm a can be a rigid beam 34 as shown in fig1 4 and 8 or a hydraulic cylinder 36 as shown in fig5 and 9 in the embodiments shown in fig1 11 and 13 the shovel arm assembly c is a multi beam assembly and comprises a first beam section 32 39 fig6 and 10 or 32 34 fig7 12 and 13 a second beam section 34 and means including a pin 36 for pivotally connecting the second beam section 34 on the first beam section 32 39 or 32 34 respectively in the embodiments of fig6 fig7 and fig1 13 the first beam section 32 39 32 34 is connected to the stroke arm a at the common point z and the other end of the shovel arm cylinder d is connected to the second beam section 34 in the embodiment of the multi beam shovel arm assembly shown in fig6 and 10 the first beam section 32 39 of the shovel arm assembly c is rigidly connected to the stroke arm b 39 and the stroke arm cylinder a 39 near the common point z.