[0025] The motor of the machine is preferably an electrical motor. It is a preferable object of the invention to design the drilling machine to be ergonomically advantageous. This means inter alia that the necessary electric cable and the water hose that is necessary for the water supply are led into the machine from the same direction, preferably from below, when the machine is directed with its drilling shaft horizontally arranged. By the water chamber being annular, it can be given a relatively large radial extension in the machine, i.e. transversal to the longitudinal direction of the drilling shaft, which means that water can be led into a lower portion of the annular water chamber, thus enabling a water inlet to the water chamber at a short radial distance from the underside of the drilling machine, which is a true constructional advantage. It is also possible to lead out the water from the water chamber, via the channel in the drilling shaft, at a position in the upper part of the annular water chamber, which constitutes an important adaptation to a beneficial positioning of the drilling shaft in the machine.

 [0026] Additional aspects, characteristics and advantages of the invention will be clear from the appended claims and from a detailed description of a preferred embodiment.

 BRIEF DESCRIPTION OF THE DRAWINGS

 [0027] In the following, a preferred embodiment of the drilling machine according to the invention will be described with reference to the appended drawing figures, of which:

 [0028] FIG. 1 is a view in perspective of a drilling machine according to a first embodiment of the invention,

 [0029] FIG. 2 shows the front and lower parts of said machine, partially in section,

 [0030] FIG. 3 shows an exploded view in perspective of a front machine unit and a motor housing end cover, as seen obliquely from the rear right and in accordance with the first embodiment,

 [0031] FIG. 4 shows the same machine unit and motor housing end cover as in FIG. 3, as seen obliquely from below, from the rear left,

 [0032] FIG. 5 shows an axial section of the parts of the drilling machine that are most essential for the understanding of the invention, according to the first embodiment of the invention,

 [0033] FIG. 6 shows, in a view in perspective obliquely from the rear left, an axial section of the motor housing end cover and a gear housing end cover, brought in abutment with each other, according to the first embodiment of the invention,

 [0034] FIG. 7 is a view in perspective of a drilling machine according to a second embodiment of the invention,

 [0035] FIG. 8 is a view in perspective of the same drilling machine as in FIG. 7, in which the water conduit has been detached,

 [0036] FIG. 9 shows an exploded view of a gear housing end cover, a sealing insert and the parts of the water conduit therefore, in accordance with a second embodiment of the invention,

 [0037] FIG. 10 shows an axial section of the drilling machine according to the second embodiment, and

 [0038] FIG. 10A shows an enlarged portion of the section in FIG. 10, which shows the drilling shaft, the sealing insert and parts of the water conduit for the sealing insert.

 DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

 [0039] Referring first to FIG. 1, a drilling machine according to the invention is generally denoted 1. Its principal parts are a rear unit 2 with a handle 3, and a front unit 4. A hand protector bow 5 extends between the lower end of the handle 3 and the underside of the front unit 4. An electrical cable 6 extends into the handle 3, from below. In parallel with the electrical cable 6, a water hose 7 extends from below and into a front portion 10 of the hand protector bow 5. A drilling shaft 8 has a front attachment 9 for accessories, to which attachment a core drill steel (not shown) or some other tool can be attached. A front handle can, as is known per se, be mounted to a cylindrical portion 11 of the front end of the front unit 4. The rear unit 2 houses an electrical motor 14 that can be manoeuvred by a switch or some other manoeuvring means 15 in the handle 3. A motor shaft that extends from the electrical motor 14 has been denoted 16. The electrical motor 14 is housed in a motor housing 17. A motor housing end cover that faces the front unit 4, has been denoted 18. The front unit 4 comprises a gear box housing 20, a gear box housing end cover 21 that faces the motor housing, and in the gear box housing 20 a gear box, here called transmission 22.