Chinese Pointed Spike Bayonet

 The two on the left are Chinese Pointed Angle Grind Spike Bayonet with their sharp tip ground from both sides angled toward the front and bottom. The bottom right is a Chisel Tip Spike AK47 Bayonet that is ground from the top angled down in a “Chisel” shape 

 The other side of the two Chinese Pointed Spike Bayonets
The bottom is a “Chisel Tip” AK47 Spike Bayonet

The top two are examples of the Chinese Angle Grind Spike Bayonets.
The bottom is a Chisel Tip Spike AK47 Bayonet

 These connect to a stud under the front sight on the rifle. The screw holds the outer locking sleeve onto the bayonet (compressing the spring)