Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
143 words
A spindle unit for a machine tool comprising a main spindle (2) formed as a solid shaft of a rigid material, a spindle head (1) rotatably supporting the main spindle (2) by means of bearings (3, 4, 5), an adapter (8) shrink-fitted onto a front end of the main spindle (2) and having one of a short columnar lug (9, 9 a ) and a cylindrical bore (13, 13 a ) extending integral with and coaxial with the main spindle (2), and a tool-cramping device including a tool holder (12) carrying a rotary tool (10) and capable of being shrink-fitted tightly on the columnar lug (9, 9 a ) or in the cylindrical bore (13, 13 a ) whereby the tool holder (12) is disengagable from the adapter so as to allow replacement of the rotary tool (10) with another rotary tool (10)
Claim 2
Dependent Claim
212 words
A tool-cramping device in a spindle unit for a machine tool having a main spindle (2) rotatably supported in a spindle head (1), the tool-cramping device being of such a structure that a rotary tool (10) is replaceably held by a front end of the main spindle (2), the tool-cramping device comprising: an adapter (8) disposed at the front end of the main spindle (2); a tool holder (12) holding the rotary tool (10); a short columnar lug (9, 9 a ) formed integral either with the adapter (8) or with the tool holder (12); a cylindrical bore (13, 13 a ) formed integral either with the tool holder (12) or with the adapter (8) and to be shrink-fitted on the columnar lug (9, 9 a ), whichever of the adapter (8) or the tool holder (12) has the cylindrical bore 13, 13 a ) therein being made of a material having a thermal expansion coefficient higher than that of the material of which the other of the tool holder (12) or the adapter (8) is made; and a rapid heating means (14) and a rapid cooling means (15) respectively to heat and cool whichever of the tool holder (12) and the adapter (8) comprises the cylindrical bore (13, 13 a ).
Claim 3
Dependent Claim
39 words
A tool-cramping device according to claim 2, wherein the rapid heating means (14) and the rapid cooling means (15) are disposed in the spindle head (1) and in the proximity of the front end of the main spindle (2).
Claim 4
Dependent Claim
33 words
A tool-cramping device according to claim 2, wherein the rapid heating means (14) and the rapid cooling means (15) are disposed in a tool transporter (21, 24) to transport the rotary tool (10).
Claim 5
Dependent Claim
52 words
A tool-cramping device according to any one of claims 2 to 4, further comprising a vibrator (23) to impart vibration either to the adapter (8) or to the tool holder (12) while the rapid heating (14) and cooling (15) means are heating or cooling the adapter (8) of the tool holder (12).
Claim 6
Dependent Claim
45 words
A tool-cramping device according to any one of claims 2 to 4, further comprising a pressing means (24) provided in the tool transporter and urging the tool holder (12) towards the adapter (8) while the adapter (8) is being engaged with the tool holder (12).