JP2013151072A - Recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recording device that is further reduced in size and has more excellent lubricity and durability.SOLUTION: A drive shaft transmits a driving force of rotation to a roller that is one example of a conveyance means for conveying a paper sheet which is one example of a recorded medium. A bearing 21 receives the drive shaft on an inner peripheral surface 31. On the inner peripheral surface of the bearing 21, grease grooves 33-1 and 33-2 being the grease grooves 33-1 and 33-2 for storing grease are formed which extend in a direction intersecting with both axial and circumferential directions.

Description

The present invention relates to a recording apparatus, and more particularly to a recording apparatus for recording on a recording medium.
The recording apparatus includes apparatuses such as an ink jet printer, a copying machine, and a facsimile.

  In order to reduce shaft loss and improve durability in sliding bearings, it is common to set a separate part using a material with excellent slidability in the bearing part and use lubrication with grease. However, a material having excellent slidability is often expensive. Furthermore, it is difficult to perform integral molding or the like, leading to an increase in cost.

  If you want to improve the same performance with general materials that you do not want to increase the cost, you can respond by increasing the sliding area, setting a large grease storage groove and improving the lubrication sustainability. FIG. 10 and FIG. 11 are diagrams showing the configuration of the bearing 101 provided with a grease collecting groove in the axial (circumferential) direction. FIG. 10 is a perspective view showing the configuration of the bearing 101. FIG. 11 is a plan view showing the configuration of the bearing 101.

  A grease reservoir groove 103 extending in the axial (circumferential) direction is provided on the inner peripheral surface 102 of the bearing 101. The inner peripheral surface 102 is in contact with the shaft and receives a force from the shaft. The grease reservoir groove 103 stores grease for lubrication. The grease reservoir groove 103 has a V-shaped cross section. The grease stored in the grease storage groove 103 is appropriately supplied between the shaft and the inner peripheral surface 102. This is expected to improve lubrication performance and reduce axial loss.

  For the same improvement, a bearing having a cross-shaped grease reservoir groove in which a circumferential groove and a central groove are combined may be used. 12 and 13 are views showing the configuration of the bearing 121 provided with a cross-shaped grease reservoir groove. FIG. 12 is a perspective view showing the configuration of the bearing 121. FIG. 13 is a plan view showing the configuration of the bearing 121.

  The inner circumferential surface 122 of the bearing 121 is provided with a grease pool groove 123 and grease pool grooves 124-1 and 124-2. The inner peripheral surface 122 is in contact with the shaft and receives a force from the shaft. The grease reservoir groove 123 is formed to extend in the axial (circumferential) direction. Grease pool grooves 124-1 and 124-2 are formed to extend in the axial center (axis) direction. Grease for lubrication is stored in the grease pool groove 123 and the grease pool grooves 124-1 and 124-2. The cross sections of the lease reservoir groove 123 and the grease reservoir grooves 124-1 and 124-2 are V-shaped. The grease stored in the lease storage groove 123 and the grease storage grooves 124-1 and 124-2 is appropriately supplied between the shaft and the inner peripheral surface 122.

  Further, the rotary shaft of the transport drive roller is applied to a transport roller composed of a transport drive roller and a transport driven roller that transports the recording material fed from the upstream to the transport guide unit and guides it to the recording position. In some cases, a bearing portion that pivotally supports the shaft and a bearing portion that pivotally supports the rotation shaft of the driven roller for conveyance are integrally formed with respect to a single guide base (see, for example, Patent Document 1).

JP 2007-186309 A

  However, as shown in FIG. 10 and FIG. 11, if only the grease reservoir groove 103 extending in the axial (circumferential) direction is provided, the width w shown in FIG. 101) becomes larger. As a result, the product itself becomes large. Further, the lubrication in the region A shown in FIG. 11 tends to be insufficient.

  Further, as shown in FIGS. 12 and 13, when the grease pool grooves 124-1 and 124-2 are provided in addition to the grease pool groove 123, the portion other than the vicinity of the groove, that is, the region shown in FIG. There was a possibility that lubrication in B would be insufficient. Although it is conceivable to increase the number of grease reservoir grooves extending in the axial center (axis) direction, the area of the bearing portion is reduced, and the load per unit area is increased. Furthermore, since the corners of the grease reservoir grooves 124-1 and 124-2 extending in the axial center (axis) direction are orthogonal to the direction of rotation of the received shaft, the grease oil film is scraped by local contact with the shaft when the shaft rotates. End up. For this reason, there is a risk of local wear, and conversely, durability may be reduced.

  The present invention has been made in view of such a situation, and provides a recording apparatus that is superior in the lubricity and durability of a bearing.

  A recording apparatus according to a first aspect of the present invention includes: a shaft that transmits a rotational driving force to a transport unit that transports a recording medium; and a bearing that receives the shaft on an inner peripheral surface, the inner periphery of the bearing The surface is provided with a groove for accumulating a lubricant that extends in a direction intersecting both the axial direction and the circumferential direction.

  According to this aspect, since the groove for storing the lubricant extends in a direction intersecting with both the axial direction and the circumferential direction, sufficient lubrication can be achieved even if the width of the groove is reduced, and therefore, on the inner peripheral surface of the bearing. Since the region where lubrication tends to be insufficient can be narrowed, more excellent lubricity and durability can be obtained.

  A recording apparatus according to a second aspect of the present invention is characterized in that, in the first aspect, a plurality of the grooves are provided so as to intersect with each other. According to this aspect, since the region where lubrication tends to be insufficient can be further narrowed, further superior lubricity and durability can be obtained.

  The recording apparatus according to a third aspect of the present invention is characterized in that, in the first or second aspect, the groove has a shape extending along the outer periphery of the ring.

  The recording apparatus according to a fourth aspect of the present invention is characterized in that, in the first or second aspect, the groove has a shape extending along a spiral.

  A recording apparatus according to a fifth aspect of the present invention is the recording apparatus according to any one of the first to fourth aspects, wherein a cross section when the groove is cut along a plane orthogonal to the extending direction of the groove is formed in a substantially V shape. The angle forming the V-shape is 45 degrees or more. According to this aspect, when the bearing is formed by a molding process such as resin molding, a so-called undercut portion is difficult to be formed, and a slide mechanism or the like is not required for molding the groove, so that a reduction in productivity can be avoided. .

2 is a perspective view illustrating an internal configuration of the printer 1. FIG. It is a perspective view which shows the structure of a bearing. It is a top view which shows the structure of a bearing. It is a left view which shows the structure of a bearing (A arrow line view of FIG. 2). It is a perspective view which shows the structure of the bearing which provided the helical grease groove | channel. It is a top view which shows the structure of the bearing which provided the helical grease groove | channel. It is a left view (B arrow view of FIG. 5) which shows the structure of the bearing which provided the helical grease groove. It is a figure which shows the pitch P of the spiral S which shows the direction where a grease groove | channel is extended. It is a figure which shows the example of the cross section of a grease groove | channel. It is a perspective view which shows the structure of the conventional bearing. It is a top view which shows the structure of the conventional bearing. It is a perspective view which shows the structure of the conventional bearing. It is a top view which shows the structure of the conventional bearing.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing an internal configuration of a printer 1 as an example of an embodiment of the present invention. The printer 1 is a printing apparatus that is an example of a recording apparatus, and records characters, images, and the like on a sheet that is an example of a recording medium. The main body 11 of the printer 1 is formed of resin or metal and has a function as a so-called frame. The main body 11 of the printer 1 is provided with a drive shaft 12 and a roller 13.

  A gear 14 is provided at one end of the drive shaft 12, and a rotation sensor 15 is provided at the other end. When the rotational force of a motor (not shown) is transmitted to the gear 14 and the gear 14 is rotated, the drive shaft 12 rotates together with the gear 14. The drive shaft 12 itself functions as a roller. When the roller 13 is in contact with the drive shaft 12 and the drive shaft 12 rotates, the roller 13 provided to rotate freely rotates. The drive shaft 12 and the roller 13 pinch and convey the paper. The drive shaft 12 and the roller 13 are an example of a transport unit that transports a sheet that is an example of a recording medium. The rotation angle of the drive shaft 12 is detected by the rotation sensor 15. The drive shaft 12 is a metal shaft in the present embodiment, and wear-resistant particles are attached to the outer peripheral surface of the region in contact with the paper to form a high friction layer. Moreover, the outer peripheral surface of the area | region which contacts the bearing 21 mentioned later in the drive shaft 12 is formed smoothly.

  The main body 11 of the printer 1 is provided with a carriage 16. The carriage 16 moves in the width direction of the paper by the power of a motor (not shown) when recording on the paper. The carriage 16 is provided with a recording head (not shown) on the side facing the paper. The carriage 16 moves in the width direction with respect to the paper that is nipped and conveyed by the drive shaft 12 and the roller 13, and a recording head (not shown) ejects ink, whereby characters and images are recorded on the paper. .

  Next, the configuration of the bearing 21 provided with a ring-shaped (ring-shaped) grease groove extending in a direction intersecting both the axial direction and the circumferential direction will be described with reference to FIGS. FIG. 2 is a perspective view showing the configuration of the bearing 21. FIG. 3 is a plan view showing the configuration of the bearing 21. FIG. 4 is a left side view showing the configuration of the bearing 21 (viewed in the direction of arrow A in FIG. 2).

  In the main body 11, bearings 21 for receiving the drive shaft 12 are formed in the vicinity of both ends of the drive shaft 12. The bearing 21 is a sliding bearing made of resin or metal. For example, when the main body 11 is injection-molded, the bearing 21 is formed integrally with the main body 11 by the injection molding.

  The bearing 21 is formed with an inner peripheral surface 31 that is in contact with the drive shaft 12 and receives the drive shaft 12. The inner peripheral surface 31 is formed in a shape obtained by inverting the shape of the outer peripheral surface in contact with the bearing 21 among the outer peripheral surfaces of the drive shaft 12. Specifically, for example, the inner peripheral surface 31 is formed in a substantially semi-cylindrical shape divided into two by a plane passing through the center of the bottom surface.

  The inner peripheral surface 31 is provided with a grease groove 32 extending in the axial (circumferential) direction. The inner circumferential surface 31 is provided with grease grooves 33-1 and 33-2 extending in a direction intersecting with both the axial direction and the circumferential direction. Each of the grease grooves 33-1 and 33-2 is formed in a ring shape, that is, in a ring shape. In other words, each of the grease grooves 33-1 and 33-2 is formed in the same shape as a part of the ring (ring) (forms a shape extending along the outer periphery of the ring).

  The grease groove 33-1 and the grease groove 33-2 intersect at the inner peripheral surface 31. More specifically, the grease groove 33-1 and the grease groove 33-2 intersect at the grease groove 32. More specifically, the grease groove 33-1 and the grease groove 33-2 are points where a straight line in the vertical direction passing through the center of the drive shaft 12 and the inner peripheral surface 31 intersect with each other. Intersect at a point. Grease for lubrication is stored in the grease groove 32, the grease groove 33-1 and the grease groove 33-2. The lengths of the grease groove 33-1 and the grease groove 33-2 can be made longer than the groove 32 extending in the axial center (axis) direction, so that when formed in such a manner, more grease can be stored. it can.

  The cross sections of the grease groove 32, the grease groove 33-1 and the grease groove 33-2 (cross section cut along a plane orthogonal to the direction in which the grooves extend) are formed in a substantially V shape. The grease accumulated in the grease groove 32, the grease groove 33-1 and the grease groove 33-2 is extended by the rotation of the drive shaft 12 and supplied between the drive shaft 12 and the inner peripheral surface 31. Since the grease groove 33-1 and the grease groove 33-2 intersect at the inner peripheral surface 31, the inner peripheral surface 31 has a long (far) distance from the grease groove 32, the grease groove 33-1 and the grease groove 33-2. The number of parts is reduced, and this makes it easier for the grease to spread over the entire inner peripheral surface 31.

In FIG. 3, the area indicated by the reference symbol A ′ and the broken line indicates an area where no grease groove is formed in this embodiment in order to compare the conventional example shown in FIG. 11 or FIG. 13 with this embodiment. As is clear from the comparison between the conventional example shown in FIG. 11 or FIG. 13 and the present embodiment, according to the present embodiment, a region having a long (far) distance from the grease groove is reduced.
Therefore, more excellent lubricity and durability can be obtained. In other words, since the range in contact with the grease can be expanded both in the axial direction and in the circumferential direction, the thickness of the grease is thin, and in particular, the area where lubrication is likely to be insufficient due to changes over time can be reduced, and the durability of the lubrication performance can be maintained. improves.

  Therefore, the bearing width w shown in FIG. 3 can be made narrower. The load in the vertical direction applied to the drive shaft 12 is less likely to be applied as a force to the portion of the inner peripheral surface 31 that is at an angle of 45 degrees or more with respect to the vertical direction. The outer peripheral surface and the inner peripheral surface 31 are difficult to contact. Therefore, as shown in FIG. 4, the straight line m passing through the center of the drive shaft 12 and the center of the grease groove 33-1 or the grease groove 33-2 at the end of the inner peripheral surface 31, and the center of the drive shaft 12 are arranged. The grease groove 33-1 or grease at the end of the inner peripheral surface 31 from the center of the drive shaft 12 is such that the angle θ formed by the straight line n passing through is 45 degrees or less, and more preferably 40 degrees. A lateral distance L to the center of the groove 33-2 is determined.

  Alternatively, the angle α (FIG. 3) at which the grease groove 33-1 and the grease groove 33-2 intersect as shown in FIG. 3 is determined so that the angle θ is 45 degrees or less, more preferably 40 degrees.

  Moreover, the grease groove | channel extended in the direction which cross | intersects with respect to both an axial direction and the circumferential direction can also be made into a helical form. Next, the structure of the bearing 21 provided with a helical grease groove will be described with reference to FIGS. FIG. 5 is a perspective view showing the configuration of the bearing 21 provided with a helical grease groove. FIG. 6 is a plan view showing the configuration of the bearing 21 provided with a helical grease groove. FIG. 7 is a left side view showing the configuration of the bearing 21 provided with a helical grease groove.

  The bearing 21 is formed with an inner peripheral surface 51 that is in contact with the drive shaft 12 and receives the drive shaft 12. The inner peripheral surface 51 is formed in a shape obtained by inverting the shape of the outer peripheral surface in contact with the bearing 21 among the outer peripheral surfaces of the drive shaft 12. Specifically, for example, the inner peripheral surface 51 is formed in a substantially semi-cylindrical shape divided into two by a plane passing through the center of the bottom surface. The inner peripheral surface 51 is provided with a grease groove 52 extending in the axial (circumferential) direction.

  The inner peripheral surface 51 is provided with grease grooves 53-1 and 53-2 extending in a direction intersecting with both the axial direction and the circumferential direction. Each of the grease grooves 53-1 and 53-2 is formed in a spiral shape. That is, each of the grease grooves 53-1 and 53-2 is formed in the same shape as the shape of a part of the spiral. As shown in FIG. 8, the pitch P of the spiral S indicating the direction in which the grease grooves 53-1 or 53-2 extend is, for example, four times the bearing width w of the bearing 21 shown in FIG.

  The grease groove 53-1 and the grease groove 53-2 intersect at the inner peripheral surface 51. More specifically, the grease groove 53-1 and the grease groove 53-2 intersect at the grease groove 52. More specifically, the grease groove 53-1 and the grease groove 53-2 are the points where the vertical straight line passing through the center of the drive shaft 12 intersects the inner peripheral surface 51, and are on the grease groove 52. Intersect at a point. Grease for lubrication is stored in the grease groove 52, the grease groove 53-1, and the grease groove 53-2. Since the grease groove 53-1 and the grease groove 53-2 can be made longer than the groove 52 extending in the axial center (axis) direction, a larger amount of grease can be stored when formed in this way. it can.

  The grease accumulated in the grease groove 52 and the grease grooves 53-1 and 53-2 is extended by the rotation of the drive shaft 12 and supplied between the drive shaft 12 and the inner peripheral surface 51. Since the grease groove 53-1 and the grease groove 53-2 intersect at the inner peripheral surface 51, the inner peripheral surface 51 has a long (far) distance from the grease groove 52, the grease groove 53-1, and the grease groove 53-2. Since the number of parts is reduced and the grease easily spreads over the entire inner peripheral surface 51, more excellent lubricity and durability can be obtained. In other words, since the range in contact with the grease can be expanded both in the axial direction and in the circumferential direction, the thickness of the grease is thin, and in particular, the region where lubrication is likely to be insufficient due to changes over time can be reduced. Therefore, the durability of the lubricating performance is improved.

  The cross sections of the grease groove 52, the grease groove 53-1, and the grease groove 53-2 (cross sections cut along a plane orthogonal to the direction in which the grooves extend) are formed in a substantially V shape. FIG. 9 is a diagram illustrating an example of a cross section of the grease groove 53-1 and the grease groove 53-2. The angle β forming the V shape of the cross section of the grease groove 53-1 and the grease groove 53-2 is 45 degrees or more, more preferably 50 degrees or more, and further preferably 70 degrees or more. In this way, when the main body 11 and the bearing 21 are integrally formed by a molding process such as resin molding, a so-called undercut portion is difficult to be formed, and a slide mechanism or the like is not required in the mold, resulting in a decrease in productivity. Can be avoided. For example, when the mold for molding the main body 11 is composed of an upper mold and a lower mold, the mold can be opened straight in a direction away from either or both of the upper mold and the lower mold.

  And according to the bearing which concerns on this invention, since lubricity and durability improve, the bearing width w shown by FIG. 6 can be made narrower. The load in the vertical direction applied to the drive shaft 12 is less likely to be applied as a force to the portion of the inner peripheral surface 51 that is at an angle of 45 degrees or more with respect to the vertical direction. The outer peripheral surface and the inner peripheral surface 51 are difficult to contact.

  In consideration of this, as shown in FIG. 7, a straight line m passing through the center of the drive shaft 12 and the center of the grease groove 53-1 or the grease groove 53-2 at the end of the inner peripheral surface 51, and the drive shaft 12. The angle θ formed by the vertical straight line n passing through the center of is 45 degrees. Note that an angle θ formed by a straight line passing through the center of the drive shaft 12 and the center of the grease groove 53-1 or the grease groove 53-2 at the end of the inner peripheral surface 51 and a vertical straight line passing through the center of the drive shaft 12. However, the pitch P of the spiral S indicating the direction in which the grease groove 53-1 or 53-2 extends is determined so that the angle is 40 degrees or more.

  Thus, since the grease groove extends in a direction intersecting with both the axial direction and the circumferential direction, the grease groove can be sufficiently lubricated even if the width of the grease groove is narrowed, so that the size can be further reduced and the lubrication becomes insufficient. Since the easy region can be made narrower, more excellent lubricity and durability can be obtained.

  A partition having the same height as the inner peripheral surface 31 or 51 is provided at the end of the inner peripheral surface 31 or 51 at the end of the grease groove 33-1 or 33-2 or 53-1 or 53-2. Can be provided. By doing in this way, it can prevent that grease is discharged | emitted out of the bearing 21 from the grease groove | channel 33-1 or 33-2 or 53-1 or 53-2 by rotation of the rotating shaft 12. FIG.

  As described above, the driving shaft 12 transmits the rotational driving force to the roller 13 which is an example of a conveying unit which conveys a sheet which is an example of a recording medium, and the bearing 21 causes the driving shaft 12 to move to the inner peripheral surface 31. In the inner circumferential surface of the bearing 21, grease grooves 33-1 and 33-2 extending in a direction intersecting with both the axial direction and the circumferential direction, and grease grooves 33-1 and 33-2 for collecting grease are provided. Since 33-2 is provided, more excellent lubricity and durability can be obtained for the bearing.

  Further, since the grease grooves 33-1 and 33-2, which are a plurality of intersecting grease grooves, are provided on the inner peripheral surface 31 of the bearing 21, the region where lubrication is likely to be insufficient can be further narrowed and further improved. High lubricity and durability can be obtained.

  Furthermore, an annular grease groove 33-1 or 33-2 can be provided on the inner peripheral surface 31 of the bearing 21.

  Further, a helical grease groove 53-1 or a grease groove 53-2 can be provided on the inner peripheral surface 51 of the bearing 21.

  The cross section in the circumferential direction of the grease groove 53-1 or the grease groove 53-2 can be formed in a substantially V shape so that the angle forming the V shape can be 45 degrees or more. A slide mechanism or the like is not required for forming the groove, and a reduction in productivity can be avoided.

  Although the printer 1 has been described as a printing apparatus, it may be a recording apparatus that is a printing apparatus, a copying machine, or a facsimile apparatus.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say. For example, the above-described relationship between the angle θ, the angle β, the pitch P of the spiral S, and the bearing width w can be appropriately set to other values. In the above-described embodiment, grease having a high viscosity is described as an example of the lubricant. However, the lubricant is not limited to the grease, and may be a low-viscosity lubricating oil or the like. good.

  DESCRIPTION OF SYMBOLS 1 Printer, 11 Main body, 12 Drive shaft, 13 Roller, 14 Gear, 15 Rotation sensor, 16 Carriage, 21 Bearing, 31 Inner peripheral surface, 32 Grease groove, 33-1 and 33-2 Grease groove, 51 Inner peripheral surface, 52 Grease groove, 53-1 and 53-2 Grease groove

Claims (5)

A shaft for transmitting a rotational driving force to a conveying means for conveying a recording medium;
A bearing for receiving the shaft on the inner peripheral surface,
The recording apparatus according to claim 1, wherein a groove for storing a lubricant is provided on an inner peripheral surface of the bearing that extends in a direction intersecting both the axial direction and the circumferential direction. The recording apparatus according to claim 1, wherein the plurality of grooves intersect with each other.
A recording apparatus. The recording apparatus according to claim 1, wherein the groove has a shape extending along an outer periphery of the ring.
A recording apparatus. The recording apparatus according to claim 1 or 2, wherein the groove has a shape extending along a spiral.
A recording apparatus.   5. The recording apparatus according to claim 1, wherein a cross section when cut by a plane orthogonal to the extending direction of the groove is formed in a substantially V shape, and an angle forming the V shape is formed. A recording apparatus characterized by being at least 45 degrees.

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