Image reading apparatus provided with image sensor contained in slidable carriage

An image reading apparatus comprising:

• a contact glass having an upper surface and a lower surface which are opposite to each other, the upper surface being configured to support a manuscript thereon;
• an image sensor unit disposed below the contact glass and including:
• an image sensor configured to read an image of the manuscript supported on the upper surface of the contact glass, the image sensor extending in a first direction and having a first end and a second end which are opposite to each other in the first direction, an upper surface facing the lower surface of the contact glass, and a lower surface opposite to the upper surface;
• and
• a first spacer and a second spacer disposed at the first end and the second end of the image sensor, respectively, and each configured to contact the lower surface of the contact glass to thereby keep constant a distance between the upper surface of the image sensor and the lower surface of the contact glass,
• a carriage configured to carry the image sensor unit in a second direction perpendicular to the first direction, the carriage including a first spring support protrusion and a second spring support protrusion which protrude upward;
• a guide member extending in the second direction and configured to guide the carriage in the second direction;
• and
• a first coil spring and a second coil spring wound around and extending further upward than the first spring support protrusion and the second spring support protrusion, respectively, and each configured to urge the image sensor unit toward the contact glass such that the first spacer and the second spacer each contact the lower surface of the contact glass,
• wherein the first coil spring and the second coil spring are offset from the image sensor in the second direction, and an upper end of each of the first coil spring and the second coil spring is located below the upper surface of the image sensor and above the lower surface of the image sensor, and
• wherein the first coil spring is located closer, in the first direction, to the first spacer than to the guide member, and the second coil spring is located closer, in the first direction, to the second spacer than to the guide member.