JP2543148Y2 - Dental handpiece - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dental handpiece.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, a dental handpiece has a rotating shaft 2 on which a turbine blade 1 is fixed, and ball bearings which are fitted on the rotating shaft 2 on both sides of the turbine blade 1. 3 and 3 and a housing 4 for supporting the ball bearings 3 and 3 (see Japanese Utility Model Application Laid-Open No. 56-130714).
issue). Then, lubricating oil is mixed in a mist state into the air for rotating the turbine blade 1 at a high speed, and the lubricating oil mixed in the air is used to lubricate the ball bearing 3 and prevent corrosion.

[0003]

However, in the ball bearing 3 of the conventional dental handpiece described above, the shield plate 6 is fixed only to the outer end of the outer ring 5 for supplying lubricating oil. . Therefore, the lubricating oil leaks easily due to the low shielding effect, and it is necessary to supply the lubricating oil. Therefore, there is a problem that the consumption of the lubricating oil increases. Also, the leaked lubricant will scatter into the patient's mouth,
There was a problem that continuous supply of lubricating oil was not possible. Furthermore, since the sound insulating effect of the shield plate 6 is low, there is a problem that air noise and rolling noise of the ball 7 leak and noise increases.

Accordingly, an object of the present invention is to provide a dental handpiece that can reduce leakage of lubricating oil and reduce noise.

[0005]

In order to achieve the above object, the present invention provides a rotating shaft on which turbine blades are fixed, and ball bearings which are fitted on the rotating shaft on both sides of the turbine blades.
In a dental handpiece provided with a housing for supporting the ball bearing, the ball bearing is formed of a deep groove ball bearing, and a plurality of balls of the bearing are formed of a ceramic material, and the holding of each ball is performed. The vessel is made of a material having lubricity, and shield plates are fixed to both ends of the outer ring, respectively.

[0006]

By shielding the shield plates at both ends of the outer ring, the shielding effect is improved, the leakage of the lubricating oil is reduced, the number of times of replenishing and the consumption of the lubricating oil are reduced, and the lubricating oil is injected into the mouth of the patient. Spatter is also reduced. In addition, since the sound insulation effect is also improved, noise is reduced. Further, since the ball is a ceramic material and the retainer is a material having lubricity, seizure resistance is improved even when the temperature rises or lubricating oil decreases due to sealing by both shield plates.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments.

In FIG. 2, 10 is a housing, 11 is a rotating shaft, 12 is a turbine blade fixed to the rotating shaft 11, and 13 and 13 are balls for rotatably supporting the rotating shaft 11 on both sides of the rotating shaft 11. Bearings. The rotating shaft 1
A dental bar portion 14 is formed at the leading end of 1, and a hand (not shown) with a grindstone is connected to the dental bar portion 14. Spacers 15, 15 are interposed between the turbine blade 12 and the ball bearings 13, 13 to restrain the turbine blade 12 from moving in the axial direction.

As shown in detail in FIG. 1, the ball bearing 13 includes an inner ring 16, an outer ring 17, and a plurality of balls 18,.
18, a retainer 19, and two shield plates 20, 20
And stop rings 21 and 21.

The inner race 16 and the outer race 17 are made of corrosion-resistant stainless steel. The width W of the inner ring 16 and the outer ring 17 is a wide type wider than the normal type. In addition, the race 1 of the outer peripheral surface of the inner ring 16 and the inner peripheral surface of the outer ring 17
6a and 17a are of a deep groove type.

The balls 18 fitted in the ball receiving grooves 16a, 17a are made of a ceramic material mainly composed of silicon nitride or sialon. The ball 18 has a rolling life equal to or higher than that of a conventional steel ball.

A retainer 19 for retaining the balls 18
Is made of a lubricating material such as a phenolic resin. The retainer 19 is crown-shaped, and its pocket opening is arranged in a direction opposite to the turbine blade 12. The retainer 19 is an inner ring guide guided by the inner ring 16 so that the tip on the pocket opening side does not contact the inner peripheral surface of the outer ring 17 due to centrifugal force.

One of the two shield plates 20, 20 is made of stainless steel, and the other is made of brass. The reason for changing the material is to know the directionality when the ball bearing 13 is assembled. The shield plates 20, 20 are disposed on both end steps 17b, 17b of the inner peripheral surface of the outer race 17, and are fixed by stainless steel retaining rings 21, 21.

According to the above configuration, since the shield plates 20, 20 are fixed to both ends of the outer race 17, respectively, the sealing effect is improved, and the leakage of lubricating oil is reduced.
As a result, the number of times of lubricating oil replenishment and consumption are reduced. In addition, the escape and leakage of air and lubricating oil are reduced, and in particular, the scattering of lubricating oil into the patient's mouth is reduced, so that discomfort is reduced. Furthermore, by both shield plates 20, 20,
The inner and outer rings 16, 17 are combined with the sound insulation effect being improved.
Is wide and the natural frequency is increased, so that the air noise and the rolling noise of the ball 18 are less likely to leak, resulting in low noise, which also reduces the discomfort of the patient.

Further, since the ball 18 is made of ceramics and the retainer 19 is made of phenolic resin having lubricity, the temperature rises and the amount of lubricating oil decreases due to the sealing by the two shield plates 20, 20. Even at times, the inner and outer rings 16, 17 and the ball 18, the ball 18 and the retainer 19,
Seizure resistance between the guide surface of the retainer 19 and the guide surface of the inner ring 16 is improved.

Furthermore, since the races 16a and 17a of the inner and outer rings 16, 17 are of a deep groove type, the inner and outer rings 1
Since there is little axial displacement of the shield plates 6 and 17,
Management of the gap of 0.20 is also facilitated.

[0017]

As is clear from the above description, the dental handpiece of the present invention is one in which the shield plates are fixed to both ends of the outer ring of the deep groove ball bearing. Therefore, the shielding effect is improved, the leakage of the lubricating oil is reduced, the number of times of replenishing and the consumption of the lubricating oil are reduced, and the scattering into the mouth of the patient is also reduced. At the same time, the sound insulation effect is also improved, resulting in low noise. In addition, since the ball of the ball bearing is made of a ceramic material and the cage is made of a material having lubricity, the temperature rises due to sealing by the two shield plates,
Even when lubricating oil is reduced, seizure resistance is improved. Further, when the ball receiving grooves of the inner ring and the outer ring are formed in deep grooves, the gap between the inner and outer rings in the axial direction is small, so that the gap between the shield plates can be easily managed.

[Brief description of the drawings]

FIG. 1 is a sectional view of a ball bearing according to the present invention.

FIG. 2 is a sectional view of the dental handpiece according to the present invention.

FIG. 3 is a sectional view of a conventional dental handpiece.

[Explanation of symbols]

10 housing, 11 rotating shaft, 12 turbine blade,
13: Ball bearing, 16: Inner ring, 17: Outer ring, 18: Ball, 19: Cage, 20: Shield plate.

Claims (1)

(57) [Scope of request for utility model registration] 1. A rotating shaft to which a turbine blade is fixed, and ball bearings fitted on the rotating shaft on both sides of the turbine blade;
In a dental handpiece provided with a housing for supporting the ball bearing, the ball bearing is formed of a deep groove ball bearing, and a plurality of balls of the bearing are formed of a ceramic material, and a holding member for holding each of the balls is provided. The vessel is made of lubricating material,
A dental handpiece, wherein shield plates are fixed to both ends of the outer ring, respectively.