JPH0615487Y2 - DC rotating electric machine - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial field of application) The present invention relates to a DC rotating electric machine having an improved structure for preventing oil scattering to the commutator side in a bearing support portion having an oil-impregnated bearing mounted thereon. Is.

(Prior Art) A bearing support portion of a conventional DC rotating electric machine is formed, for example, as shown in FIG.

Both ends of the rotary shaft 1 are supported by oil-impregnated bearings 2 made of sintered metal. An oil supply packing 3 is in sliding contact with the curved outer peripheral portion of the oil-impregnated bearing 2 to supply oil.

The bearing support portion 4 that supports the oil-impregnated bearing 2 includes the inner surface of the center portion of the end bracket 6 on the side of the commutator 5 and the bearing pressing spring 7.
With the structure, the oil-impregnated bearing 2 is pressed from both sides and held.

Further, between the commutator 5 and the oil-impregnated bearing 2, a thrust adjusting washer 8 and an oil drainer 9 whose tip is curled toward the rotary shaft are attached.

On the outer side of the oil drainer 9, an oil absorbing packing 10 is provided.
It is supported by the bearing spring retainer 11 and the cover 12.

In the DC rotating electric machine having the above-described conventional structure, when the temperature rises after the start of operation, oil seeps from the oil-impregnated bearing 2 to the sliding surface of the rotary shaft 1 for lubrication, and if the amount of oil outflow increases, centrifugal force will increase. It is scattered through the washer 8 by the action of force.

The scattered oil is received and retained by the curl portion 9A of the oil drainer 9, but if the oil retaining capacity is exceeded, it is scattered from the gap between the bearing pressing spring 7 and is absorbed by the oil absorbing packing 10.

However, since the oil outflow amount is not constant depending on the mounting direction of the rotating electric machine and the operating state, if the oil outflow amount is large, it is not sufficiently absorbed by the oil absorbing packing 10 depending on the scattering direction, and is scattered to the commutator 5 side through the gap. However, it may adhere to the brush sliding surface 5A.

The oil adhered to the brush sliding surface 5A is viscous during operation, but once stopped and becomes cool, it solidifies in a state containing carbon powder, and collides with the brush 13 during operation again, It also caused abnormal noise and abnormal wear.

Further, in the conventional structure, oil is supplied from the oil supply packing 3 to the oil-impregnated bearing 2, but the scattered oil is not collected, so that the lubricity deteriorates as the amount of impregnated oil decreases. There was a problem.

Moreover, since the above scattering prevention mechanism has a large number of parts and has a complicated structure, it has a drawback that the assembly work is troublesome and the cost is increased.

(Problems to be solved by the invention) The present invention eliminates the above-mentioned drawbacks and has an extremely simple structure.
The oil spilled in the vicinity of the impregnated bearing is collected and collected by the oil absorption packing, and the excess oil spilled during the stop is absorbed by the knurled knurls on the rotating shaft to prevent it from scattering to the commutator side. In addition to reducing abnormal noise and abnormal wear, the oil recovered by the oil absorption packing is returned to the impregnated bearing to maintain long-term lubricity, and the number of parts is small, assembly is easy and manufacturing costs are low. The object is to provide a rotating electric machine.

[Structure of the Invention] (Means for Solving the Problems) In the present invention, a linear knurl is formed on the outer periphery of the intermediate portion of a rotary shaft supported on both sides by oil-impregnated bearings, and the linear knurl is inserted into a commutator. Then, the commutator is fixed, and a recess is formed on the side surface of the commutator on the oil-impregnated bearing side, and an oil reservoir groove communicating with the linear knurl is formed on the axial center side of the recess, and the commutator end bracket is formed. The bearing retainer plate on the commutator side of the bearing support part that holds the oil-impregnated bearing provided extends inside the recess formed on the side surface of the commutator to form a pocket between the side surface of the oil-impregnated bearing. An oil absorbing packing is attached to the side portion so as to be in sliding contact with the side surface of the oil-impregnated bearing, and an annular groove is formed in the rotary shaft so as to face the packing.

(Operation) In the DC rotating electric machine of the present invention, oil flowing out from the sliding surface between the oil-impregnated bearing and the rotary shaft flows along the axial direction of the rotary shaft and flows into the annular groove formed therein. .

The oil accumulated in the annular groove is scattered outward by centrifugal force, but is collected by the oil absorbing packing arranged in the pocket portion facing the annular groove, and therefore the oil from the bearing support portion to the commutator side is collected. Can be prevented from scattering.

Further, since the oil-absorbing packing comes into contact with the oil-impregnated bearing and is mounted in the pocket portion, the oil is collected and returned to the oil-impregnated bearing again to be supplied with the oil.

Excess oil that flows down along the rotation axis during stoppage is stored in an oil reservoir groove formed on the side surface of the commutator, and is absorbed and held here by the capillary action of the crease knurls, and then to the commutator side when restarting operation. It is possible to prevent the oil from scattering.

(Embodiment) An embodiment of the present invention will be described in detail below with reference to FIG.

Both ends of the rotary shaft 1 are supported by self-aligning oil-impregnated bearings 2 made of sintered metal. An oil supply packing 3 is in sliding contact with the curved outer peripheral portion of the oil-impregnated bearing 2 to supply oil.

The bearing support portion 4 for supporting the oil-impregnated bearing 2 is sandwiched by pressing the oil-impregnated bearing 2 from both sides by the outer surface obtained by bending the center portion of the end bracket 6 toward the commutator 5 side and the inner surface of the bearing retainer spring 7. It has a structure that

An annular recess 14 is formed on the side surface of the commutator 5 on the shaft end side, and a conical oil reservoir groove 16 communicating with the linear knurls 20 of the rotary shaft 1 is formed on the shaft center side of the recess 14. Has been done. The inner diameter D of the open end of the oil reservoir groove 16 is larger than the inner diameter d of the extended end of the end bracket 6.

An annular oil draining protrusion 17 is formed on the side surface of the commutator 5 opposite to the oil reservoir groove 16 so that the linear knurls 20 between the commutator 5 and the shaft insulation 18 cover the outside of the exposed gap. Has become.

The extended end of the central portion of the end bracket 6 is located inside the recess 14 formed in the commutator 5, and a pocket is provided between the end of the commutator-side bearing pressing plate and the side surface of the oil-impregnated bearing 2. The portion 15 is formed, and the oil absorbing packing 10 is attached to the pocket portion 15.

An annular groove 19 is provided on the rotary shaft 1 so as to face the oil absorbing packing 10, and a linear knurl 20 for fixing the commutator 5 is formed so as to communicate with the oil reservoir groove 16.

In the DC rotating electric machine having the above structure, when the temperature rises after the start of operation, oil seeps from the oil-impregnated bearing 2 to the sliding surface between the oil-impregnated bearing 2 and the rotary shaft 1 for lubrication. At this time, when the outflow amount of oil increases, the oil outflowing from the sliding surface flows along the axial direction of the rotary shaft 1 and flows into the annular groove 19 formed here.

The oil accumulated in the annular groove 19 is scattered outward by centrifugal force, but is collected by the oil absorbing packing 10 arranged facing the annular groove 19, so that the bearing supporting portion 4 moves toward the commutator 5 side. It is possible to prevent the oil from scattering.

Further, since the oil absorbing packing 10 contacts the oil-impregnated bearing 2 and is mounted in the pocket portion 15, the recovered oil is returned to the oil-impregnated bearing 2 to be refueled and the lubricity is maintained for a long period of time.

Further, when the rotary shaft 1 is mounted with the output shaft side facing upward, the oil that has flowed down along the rotary shaft 1 toward the commutator 5 along the rotary shaft 1 collects from the annular groove 19 in the oil reservoir groove 16 when the operation is stopped.

When the operation is started in this state, the oil is scattered by the centrifugal force, but since the recess 14 is opened toward the oil-impregnated bearing 2 side, the oil scattered from the oil reservoir groove 16 is guided to the side opposite to the commutator 5.

Further, when the operation is stopped for a long time, the oil that has flowed down is accumulated in the oil reservoir groove 16, and further penetrates into the gap of the linear knurls 20 of the rotary shaft 1 communicating with the oil reservoir groove 16 by the capillary action to be retained therein. .

When the rotary shaft 1 is rotated again after the operation is restarted, the oil reaching the end of the crease knurl 20 by the capillary action is the portion where the crease knurl 20 of the commutator 5 and the shaft insulation 18 obtained by sintering the resin powder is exposed. The oil that has flown out through the gaps is guided by the oil-cutting protrusions 17 and guided to the opposite side of the commutator 5, and can be prevented from adhering to the brush sliding surface 5A.

[Effect of the Invention] As described above, according to the present invention, the oil that has spilled in the vicinity of the oil-impregnated bearing is collected and collected by the extremely simple structure, and the excess oil that has spilled during the stoppage is aligned with the rotation axis. The knurl absorbs it to prevent it from scattering to the commutator side and reduces the occurrence of abnormal noise and abnormal wear.At the same time, the oil absorption packing collects the oil and returns it to the oil-impregnated bearing to maintain long-term lubricity. Therefore, it is possible to obtain a DC rotating electric machine having a small number of parts, easy to assemble, and inexpensive in manufacturing cost.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing a DC rotating electric machine according to an embodiment of the present invention, and FIG. 2 is a vertical sectional side view showing a conventional DC rotating electric machine. DESCRIPTION OF SYMBOLS 1 ... Rotary shaft, 2 ... Oil impregnated bearing 3 ... Oil supply packing, 4 ... Bearing support part 5 ... Commutator, 6 ... End bracket 7 ... Bearing retainer spring, 9 ... Oil drainer 10 ... Oil absorbing packing, 14 ... Recessed part 15 ... Pocket Part, 18 ... Shaft insulation 19 ... Annular groove, 20 ... Straight knurl

Claims (1)

[Scope of utility model registration request] Claims: 1. An oil-impregnated bearing for a commutator, in which a linear knurl is formed on the outer periphery of an intermediate portion of a rotary shaft whose both sides are supported by an oil-impregnated bearing, and the linear knurl portion is inserted into a commutator to fix the commutator. On the side surface on the side of the commutator, and a commutator of a bearing support part that holds an oil-impregnated bearing provided on the commutator-side end bracket by forming an oil reservoir groove communicating with the linear knurls on the axial center side of the recess. Side bearing retainer plate is extended inside the recess formed on the side surface of the commutator to form a pocket portion between the side surface of the oil-impregnated bearing, and the oil absorption packing is slidably contacted with the side surface of the oil-impregnated bearing. And a ring-shaped groove is formed on the rotary shaft so as to face the packing.