The invention claimed is:1. An electronic circuit component mounting system comprising:a mounter main body;(a) a circuit substrate conveying and holding device held on the mounter main body that conveys, fixes, and holds a circuit substrate,(b) a head main body that is moved with respect to the mounter main body by a head moving device to any position on a movement plane inside the mounter main body,(c) at least one head-side feeder held on the head main body that supplies electronic circuit components,(d) a mounting device that receives the electronic circuit components from the at least one head-side feeder and mounts the electronic circuit components on the circuit substrate held by the circuit substrate conveying and holding device using multiple component holding tools provided on the head main body,(e) a control device that controls the circuit substrate conveying and holding device, the head moving device, the at least one head-side feeder, and the mounting device, and(f) a control device that performs control such that, during contact between the component holding tool positioned at a component mounting position and an electronic circuit component of the electronic circuit components, and during contact between the electronic circuit component and the circuit substrate, the component holding tool positioned at a component pickup position of the at least one head-side feeder and an electronic component contact each other, and the electronic circuit component and the at least one head-side feeder contact each other,wherein the head main body includes a pair of clamping devices that respectively include positioning pins that engage a pair of positioning holes on the at least one head-side feeder.2. The electronic circuit component mounting system according to claim 1, whereinthe component mounting position and the component pickup position for components supplied by the at least one head-side feeder are provided on the head main body at a different position on a moving plane of the head main body inside the mounter main body.3. The electronic circuit component mounting system according to claim 1 whereinthe mounting device additionally receives a mounter-side electronic circuit component from a mounter-side feeder provided inside the mounter main body and mounts the mounter-side electronic circuit component on the circuit substrate held by the circuit substrate conveying and holding device, and the component holding tool positioned at the component mounting position receives the mounter-side electronic circuit component from the mounter-side feeder.4. The electronic circuit component mounting system according to claim 3, whereinthe electronic circuit component mounting system is provided with a control device that performs raising/lowering axis bend correction when the component holding tool positioned at the component mounting position mounts the component on the circuit substrate held by the circuit substrate conveying and holding device, or when the component holding tool positioned at the component mounting position receives the mounter-side electronic circuit component from the mounter-side feeder.5. The electronic circuit component mounting system according to claim 1,wherein the component holding tool holds or releases the electronic circuit component by controlling electrically a magnetic force.6. The electronic circuit component mounting system according to claim 5, whereinthe at least one head-side feeder performs component supply using magnetism.7. The electronic circuit component mounting system according to claim 5,wherein the at least one head-side feeder includes a permanent magnet the rotates to supply the electronic components to the component pickup position.8. An electronic circuit component mounting system comprising:a mounter main body;(a) a circuit substrate conveying and holding device held on the mounter main body that conveys, fixes, and holds a circuit substrate,(b) a head main body that is moved with respect to the mounter main body by a head moving device to any position on a movement plane inside the mounter main body,(c) at least one head-side feeder held on the head main body that supplies electronic circuit components,(d) a mounting device that receives the electronic circuit components from the at least one head-side feeder and mounts the electronic circuit components on the circuit substrate held by the circuit substrate conveying and holding device using multiple component holding tools provided on the head main body,(e) a control device that controls the circuit substrate conveying and holding device, the head moving device, the at least one head-side feeder, and the mounting device, and(f) a control device that performs control such that, during contact between the component holding tool positioned at a component pickup position of an electronic circuit component of the electronic circuit components supplied from the at least one head-side feeder and the electronic circuit component, and during contact between the electronic circuit component and the at least one head-side feeder, the component holding tool positioned at a component mounting position and the electronic circuit component and contact each other and the electronic circuit component and the circuit substrate contact each other,wherein the head main body includes a pair of clamping devices that respectively include positioning pins that engage a pair of positioning holes on the at least one head-side feeder.9. An electronic circuit component mounting system comprising:a mounter main body;(a) a circuit substrate conveying and holding device held on the mounter main body that conveys, fixes, and holds a circuit substrate,(b) a head main body that is moved with respect to the mounter main body by a head moving device to any position on a movement plane inside the mounter main body,(c) at least one head-side feeder held on the head main body that supplies electronic circuit components,(d) a mounting device that receives the electronic circuit component components from the at least one head-side feeder and mounts the electronic circuit components on the circuit substrate held by the circuit substrate conveying and holding device using multiple component holding tools provided on the head main body,(e) a control device that controls the circuit substrate conveying and holding device, the head moving device, the at least one head-side feeders feeder, and the mounting device, and(f) a control device that performs control such that, during contact between the component holding tool positioned at a component mounting position and an electronic circuit component of the electronic circuit components, and during contact between the electronic circuit component and the circuit substrate, the component holding tool positioned at a component pickup position of a component supplied from the at least one head-side feeder and an electronic component contact each other, and the electronic circuit component and the at least one head-side feeder contact each other,wherein the head main body includes a pair of clamping devices that respectively include clamping claws that engage a pair of engaging surfaces on the at least one head-side feeder.