JP2888649B2 - Sliding thrust bearing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding thrust bearing.

[0002] Rolling bearings using bearings are used in portions where the shaft and the bearing slide at high speed. However, using a rolling bearing requires space and increases costs. Therefore, a sliding bearing is used for a portion that does not move at high speed.

[0003]

2. Description of the Related Art In a conventional sliding thrust bearing, a hole which is slidably fitted to a shaft is simply formed in a bearing body.

[0004]

In a journal bearing that supports a rotating shaft, a wedge-shaped gap is formed between the shaft 100 and the bearing 101, as shown in FIG. As a result, a so-called oil squeeze flow occurs, and the space between the shaft and the bearing is well lubricated.

[0005] However, in the thrust bearing, since such an inflow of oil does not occur, as shown in FIG. 8, the oil is pushed out at the contact portion 103 between the shaft 100 and the bearing 102, and the oil film is formed. It is easy to be cut.

As a result, there has been a drawback that the thrust load gradually increases during use for a long time, the exercise resistance increases, and the wear also increases.

SUMMARY OF THE INVENTION An object of the present invention is to solve such a conventional drawback and to provide a sliding thrust bearing having good lubricity, which does not cause oil film breakage even after long use.

[0008]

In order to achieve the above object, a sliding thrust bearing of the present invention is slidably fitted to a shaft 4 as shown in FIG. 1 for explaining an embodiment. As described above, the inner surface of the hole 11 formed in the bearing body 6 has one end near the position 5 where the contact pressure between the shaft 4 and the bearing body 6 is large. It is characterized in that at least a pair of grooves 13 and 14 are formed by being inclined.

The grooves 13 and 14 may be formed on opposite sides of the position 5 where the contact pressure is large, and a plurality of grooves 13 and 14 are formed at different positions in the axial direction. Is also good.

The bearing member 6 may be provided on a carriage 3 of a printer which reciprocates with the print head 2 mounted thereon.

[0011]

When the shaft 4 and the bearing member 6 are relatively moved in the axial direction, the oil in one groove 13 is removed by the component force generated along the inner wall of the groove 13 by the movement.
It moves to the vicinity of the position 5 where the contact pressure with the contact is large.

When the shaft 4 and the bearing body 6 are relatively moved in opposite directions, the oil in the other groove 14 is separated by the component force generated along the inner wall of the groove 13 so that the shaft 4 and the bearing body 6 It moves to the position 5 where the contact pressure is large.

[0013]

An embodiment will be described with reference to the drawings.

FIG. 2 shows a printer in which a print head 2 is arranged so as to face a print sheet 50 wound around a platen roll 1.

A carriage 3 on which the print head 2 is mounted is slidably fitted on a guide shaft (shaft) 4 fixed in parallel with the platen roll 1, and is guided by a space motor (not shown). Reciprocate along 4.

FIG. 1 shows a guide shaft 4 (hereinafter referred to as "shaft 4").
), And a sliding thrust bearing 10 provided on the carriage 3 so as to fit with the shaft 4.

The sliding thrust bearing 10 has a bearing body 6 having a round hole 11 fitted with the shaft 4 penetrating therethrough, and grooves 13 and 14 formed in the bearing body 6.

In this embodiment, the shaft 4 is fixed, against which the bearing 6 slides. Therefore, the load of the bearing body 6 and the loads of the carriage 3 and the print head 2 are all applied to the upper surface portion 5 of the shaft 4, and the shaft 4 and the bearing body 6 generate a large contact pressure at the upper surface portion 5 of the shaft 4. Have.

Each of the grooves 13 and 14 is formed so as to be inclined with respect to the axis from different sides in the axial direction (from the right and left in the figure) so that one end reaches near the upper surface portion 5 of the shaft. ing.

As shown in FIG. 1, the upwardly-sloping groove 13 formed from the right side to the upper left and the upwardly-sloped groove 14 formed from the left side to the upper right are both positioned in the axial direction. Are formed in parallel with each other, and similar grooves 13 and 14 are also formed on the opposite side (back side) across the upper surface portion 5 of the shaft.

FIGS. 3 and 4 show the operation of the above embodiment. As shown in FIG. 3, when the bearing 6 moves to the right with respect to the fixed shaft 4, the oil 60 between the shaft 4 and the bearing 6 is filled with the inner wall of the groove 13 rising to the left. Is pushed up to the upper end of the groove 13 (that is, the upper surface portion 5 of the shaft) as shown by the arrow A.

Conversely, when the bearing body 6 moves to the left with respect to the fixed shaft 4, the oil 60 between the shaft 4 and the bearing body 6, as shown in FIG. The component force generated along the inner wall of the groove 14 rising to the right pushes up the upper end of the groove 13 (that is, the upper surface portion 5 of the shaft) as shown by the arrow B.

Therefore, even when the bearing body 6 moves in either the left or right direction, the upper surface portion 5 of the shaft having a large contact pressure is lubricated. Further, since each of the grooves 13 and 14 is formed on both sides thereof with the shaft upper surface portion 5 interposed therebetween, lubrication is sufficiently performed.

The cross sections of the grooves 13 and 14 may have wall surfaces perpendicular to the peripheral surface as shown in FIG. 5, but have a wedge-shaped shape as shown in FIG. By doing so, the oil 60 is held inside, and the lubricity is further improved.

The grooves 13 and 14 do not necessarily need to be exposed on the outer surface from the hole 11 of the bearing body 6, but may be formed at least on the inner surface of the hole 11.

The sliding thrust bearing of the present invention can be widely applied not only to printers but also to other devices.

[0027]

According to the sliding thrust bearing of the present invention,
A simple sliding thrust bearing, without any special parts, simply drilling a groove to reliably lubricate the position where the contact pressure between the shaft and the bearing is large, and light bearing support with low friction for a long time Has an excellent effect that can be maintained.

[Brief description of the drawings]

FIG. 1 is a perspective view of an embodiment.

FIG. 2 is a perspective view of the printer according to the embodiment.

FIG. 3 is an operation explanatory diagram of the embodiment.

FIG. 4 is a diagram illustrating the operation of the embodiment.

FIG. 5 is a sectional view of a groove according to the embodiment.

FIG. 6 is a sectional view of a groove according to another embodiment.

FIG. 7 is a sectional view of a journal bearing.

FIG. 8 is a sectional view of a conventional thrust bearing.

[Explanation of symbols]

 4 shaft 5 upper surface portion of shaft (position where contact pressure is large) 6 bearing body 13, 14 groove

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Sho 58-195116 (JP, U) Japanese Utility Model Sho 62-9729 (JP, U) Japanese Utility Model Sho 62-85333 (JP, U) Japanese Utility Model Sho 62- 158218 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) F16C 29/02 F16C 33/10

Claims (1)

(57) [Claims] 1. A printer which reciprocates with a print head mounted thereon.
The inner surface of the puncture set pore to fit freely axial sliding in a bearing member provided on the carriage, the shaft and the bearing
On both sides of the position where the contact pressure with the body is large, from one side in the axial direction so that one end reaches near the position where the contact pressure between the shaft and the bearing body is large.
The groove direction inclined with respect to the axis, in the axial direction
A sliding thrust bearing wherein a plurality of pairs are formed at different positions .