1. A method of manufacturing a semiconductor device substrate, said method comprising the steps of:
arranging on a base a temporary fixing member for temporarily fixing an electronic component;
temporarily fixing the electronic component on the base by using the temporary fixing member;
forming a substrate body on the base and the electronic component;
removing at least a portion of the base which portion corresponds to the electronic component, thereby exposing the temporary fixing member; and
removing the temporary fixing member, thereby enabling the electronic component to make an external connection.
2. The method as claimed in claim 1, wherein the temporary fixing member is made of a metal.
3. The method as claimed in claim 2, wherein the metal is a low-melting metal.
4. The method as claimed in claim 1, wherein the temporary fixing member is a sheet member configured to be able to bond the electronic component to the base.
5. The method as claimed in claim 4, wherein the sheet member is a thermo peeling tape.
6. The method as claimed in claim 4, wherein the sheet member is a water-soluble sheet.
7. The method as claimed in claim 4, wherein the sheet member is a UV tape.
8. The method as claimed in claim 1, wherein the temporary fixing member is a liquid adhesive.
9. The method as claimed in claim 1, wherein the step of removing at least the portion of the base removes the entire base.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A power tool comprising:
a housing,
a motor housed in the housing,
an internal mechanism driven by the motor, the internal mechanism including a motion converting mechanism and a power transmitting mechanism,
an internal mechanism chamber provided formed within the housing to house at least a part of the internal mechanism,
a tool bit disposed in one end of the housing and driven by the internal mechanism in the longitudinal direction of the tool bit to perform a predetermined operation,
a handgrip connected to the other end of the housing, and
a dynamic vibration reducer including a weight and an elastic element, the elastic element being adapted to apply a biasing force to the weight, wherein the weight reciprocates in the longitudinal direction of the tool bit against the biasing force of the elastic element, whereby the dynamic vibration reducer reduces vibration which is caused in the housing in the longitudinal direction of the tool bit in the working operation, and wherein the dynamic vibration reducer is located within the internal mechanism chamber.
2. The power tool according to claim 1, wherein the internal mechanism chamber is provided as a hermetic space.
3. The power tool according to claim 1, wherein the motion converting mechanism is defined by a crank mechanism and the internal mechanism chamber is provided as a hermetic space and as a crank chamber that houses at lease the crank mechanism.
4. The power tool according to claim 1, wherein the power tool as a hammer drill comprising:
a hammer mechanism driven by the motor;
the weight being slidable in forward and rearward directions between a first end position and a second end position; and
a biasing member that biases the weight to a third position located between the first and second end positions, wherein
the housing, motor, hammer mechanism, weight and biasing member are configured to define a center of gravity of the hammer drill;
the weight provides a sufficient mass and the biasing member provides a sufficient biasing force such that sliding movement of the weight acts to:
at least partially counteract vibrations of the hammer drill, and
at least partially counteract twisting movement of the hammer drill about the center of gravity;
the biasing member includes a first spring being mounted on one single side of the weight in the forward and rearward directions and a second spring being mounted on another single side of the weight in the forward and rearward directions; and
the first and second springs each include two separate springs flanking the corresponding single side of the weight, the two springs do not overlap each other in a longitudinal direction of the hammer mechanism and in plan view of the weight.
5. The power tool as claimed in claim 4, wherein the hammer mechanism includes a piston and a striking element moveable along an axis of travel, the weight being located above the axis of travel.
6. The power tool as claimed in claim 5, wherein the axis of travel is located above the center of gravity.
7. The power tool as claimed in claim 4, wherein the sliding movement of the weight acts to at least partially counteract a twisting movement of the hammer drill along an axis substantially perpendicular to a movement of the hammer mechanism passing through the center of gravity.
8. The power tool as claimed in claim 4, wherein the sliding movement of the weight acts to at least partially counteract a twisting movement of the hammer drill along an axis substantially perpendicular to a movement of the hammer mechanism passing through the center of gravity.
9. The power tool as claimed in claim 4, wherein the sliding movement of the weight acts to at least partially counteract a twisting movement of the hammer drill along an axis substantially parallel to a movement of the hammer mechanism and an axis substantially perpendicular to the movement of the hammer mechanism passing through the center of gravity.
10. The power tool as claimed in claim 9, wherein the substantially horizontal axis is substantially perpendicular to the direction of travel of the weight.
11. The power tool as claimed in claim 4, wherein the weight is suspended by the biasing member.
12. The power tool as claimed in claim 4, wherein the hammer mechanism is driven by the motor in a reciprocating motion along a first axis that is spaced a first perpendicular distance from a center of mass, and the weight moves along a second axis that is spaced a second perpendicular distance from the center of gravity.
13. The power tool as defined in claim 1, wherein a pair of dynamic vibration reducers are provided respectively at right and left side regions.
14. The power tool as claimed in claim 1, wherein the weight of the dynamic vibration reducer is defined by a single weight.
15. The power tool as claimed in claim 1, wherein the weight of the dynamic vibration reducer has a plate like shape.
16. The power tool as claimed in claim 1, wherein the weight of the dynamic vibration reducer is defined by a single weight and the single weight has a plate like shape.
17. The power tool as claimed in claim 10, wherein the biasing member includes at least one spring.
18. The power tool as claimed in claim 17, wherein the at least one spring includes first and second springs, the first spring being mounted on a first side of the weight and the second spring being mounted on a second side of the weight.