JP4885515B2 - Toothed pulley - Google Patents

Description

  The present invention relates to a toothed pulley that is used by winding a plurality of divided toothed belts in the belt width direction.

  In general, a belt driving device in which a toothed belt is wound around a toothed pulley is likely to generate noise due to meshing between the pulley teeth and the belt teeth. Also, if the pulley alignment is misaligned and the parallelism between the pair of pulley shafts is lost, the greater the belt width, the greater the difference in the distance between the pulley shafts at both belt edges, and the tension of the toothed belt is reduced by the belt width. It is easy to make it uneven in direction and to cause poor meshing.

  In order to reduce the influence of noise and pulley alignment deviation due to such meshing of pulley teeth and belt teeth, the toothed belt wound around the toothed pulley may be divided into a plurality of divided belts in the belt width direction ( For example, Patent Document 1).

  FIG. 3 shows a perspective view of a belt driving device disclosed in Patent Document 1. As shown in FIG. In this belt driving device, a toothed belt 102 divided into two divided belts 102a and 102b in the belt width direction is hooked on a toothed pulley 101 formed by connecting two flanged pulleys 101a and 101b in the belt width direction. Constructed by winding.

  The pulleys with flanges 101a and 101b are connected so that the pulley teeth 103a and 103b are shifted from each other, and noise caused by meshing with the divided belts 102a and 102b wound around the pulleys is reduced by the phase difference.

At the center of the toothed pulley 101 in the belt width direction, there is provided a spacer ring 104 consisting of flanges on the inner ends of the flanged pulleys 101a and 101b. The spacer ring 104 has a gap between the divided belts 102a and 102b, Noise due to contact between the split belts 102a and 102b is prevented.
JP 2002-54720 A (paragraph numbers 0006, 0020, 0022, FIG. 4)

  However, the toothed pulley of Patent Document 1 has a thickness required for fixing the spacer ring to the pulley main body by welding or screwing, and the thrust received from the toothed belt while being fixed to the pulley main body. Therefore, the length of the toothed pulley in the belt width direction is increased as the spacer ring becomes thicker.

  In addition, since welding or screws are used to fix the spacer ring to the pulley body, the processing cost of the toothed pulley increases, and the spacer ring fixed to the pulley body in advance obstructs the assembly of the toothed belt. Cheap.

  According to the present invention, the length of the toothed pulley in the belt width direction can be set short while providing the spacer ring. Further, the spacer ring can be provided at a low processing cost and the assembly of the toothed belt can be facilitated. The purpose is to provide a toothed pulley.

In order to achieve the above object, a toothed pulley according to the present invention is used by wrapping a plurality of divided toothed belts in the belt width direction and having pulley teeth formed on the outer peripheral surface. And a spacer ring that is disposed on the outer peripheral side of the pulley body and interposed between adjacent split belts in the belt width direction, and the thrust received from one split belt is transmitted to the other split belt by the spacer ring. The pulley body is externally fitted so as to be movable in the belt width direction.

  According to this configuration, since the spacer ring is externally fitted to the pulley body, it is unnecessary to increase the thickness of the spacer ring for welding or screwing. Further, by making the spacer ring movable in the belt width direction, the thrust received from one divided belt is directly transmitted to the other divided belt, so that the spacer ring itself does not need to withstand the thrust. Thereby, the spacer ring can be made thin, and the length in the belt direction of the toothed pulley can be set shorter accordingly.

  Further, since the spacer ring is not fixed to the pulley body, the mounting can be facilitated. Furthermore, since the spacer ring can be easily attached, the toothed belt can be easily assembled by attaching the spacer ring to the toothed pulley when the toothed belt is assembled. In other words, by attaching the spacer ring after assembling the rear split belt, the spacer ring does not interfere with the assembly work of the toothed belt.

  If the spacer ring is movable in the rotation direction with respect to the pulley body, when the split belt is wound around the toothed pulley, the spacer ring is rotated together with the split belt to suppress wear on the side surface of the split belt, thereby reducing wear powder. Generation can be reduced.

  In order to make the spacer ring movable in the rotational direction, for example, a groove having a depth similar to the tooth groove depth is continuously formed on the outer peripheral surface of the toothed pulley, and the spacer ring is formed in this groove. The arrangement of the spacer ring can be exemplified, but if the center hole of the spacer ring is a circular hole having a diameter larger than the tip circle of the pulley teeth, the pulley body and the spacer ring are made as simple as possible to facilitate their formation. be able to.

  By forming a tooth profile that fits to the pulley teeth at the periphery of the center hole of the spacer ring, the spacer ring can be arranged up to the vicinity of the bottom of the pulley teeth, so that it is interposed in a wider range between the divided belts, The contact pressure with the split belt can be reduced.

  As described above, according to the present invention, since the spacer ring is movably fitted to the pulley body, the spacer ring can be set thin, and accordingly, the length of the toothed pulley in the belt width direction can be set short. Space can be saved. In addition, since the spacer ring is fitted to the pulley body without being fixed, the spacer ring can be arranged at a low processing cost. Further, by attaching the spacer ring when attaching the toothed belt, Assembling of the attached belt can be facilitated.

  Hereinafter, the best mode for carrying out a toothed pulley according to the present invention will be described with reference to the drawings. FIG. 1 is a view showing a toothed pulley according to the present invention, in which (a) the lower half is a side view, the upper half is an AA sectional view, (b) the lower half is a front view, and the upper half is B. It is -B sectional drawing.

  This toothed pulley 1 is used by wrapping a toothed belt 2 divided into two divided belts 2 a and 2 b in the belt width direction, and is arranged on the pulley body 3 and the outer peripheral side of the pulley body 3. And a spacer ring 4 interposed between the divided belts 2a and 2b adjacent to each other in the belt width direction, and flanges 5 disposed at both ends of the pulley body 3 to prevent the toothed belt 2 from coming off. .

  The toothed belt 2 includes divided belts 2a and 2b that are spaced apart from each other in the belt width direction, and belt teeth 6 made of helical teeth or straight teeth are formed on the inner peripheral surfaces of the divided belts 2a and 2b. ing.

  The pulley body 3 is made of, for example, a column made of steel or aluminum, and is set wider than the total width of the two split belts 2a and 2b. Pulley teeth 7 meshing with the teeth 6 are formed. A shaft hole 8 is formed at the center of the pulley main body 3 so that the pulley shaft passes through the shaft hole 8.

  The spacer ring 4 is, for example, a ring shape made of steel or synthetic resin, and the center hole 9 is a circular hole having a diameter of about 0.1 mm to 0.2 mm larger than the tip circle of the pulley tooth 7, for example. The pulley body 3 is externally fitted so as to be movable in the belt width direction and the rotation direction. The spacer ring 4 has a thickness in the central axis direction set to about 3 mm to 4 mm, for example, and an outer diameter set to the same size as the flange 5, for example. Note that the thickness of the spacer ring 4 may be appropriately set according to the material and diameter thereof, and the outer diameter of the spacer ring 4 may be larger than the pitch circle of the toothed pulley 1 and the size thereof. There is no limit.

  The flange 5 is formed in a ring shape made of steel or synthetic resin, for example, and is fitted on the small diameter portion 10 at the end of the pulley body 3 and fixed by caulking or screwing. At least one of the flanges 5 disposed at both ends of the pulley body 3 is fixed after the spacer ring 4 is mounted.

  According to the above configuration, since the spacer ring 4 disposed on the pulley body 3 is interposed between the split belts 2a and 2b, it is possible to prevent contact between the split belts 2a and 2b and prevent noise due to the contact. it can. Further, since the spacer ring 4 is movable in the rotational direction, it can be rotated together with the split belts 2a and 2b wound around the toothed pulley 1 to suppress wear on the belt side surface and reduce generation of wear powder. .

  In addition, since the spacer ring 4 is externally fitted to the pulley body 3, the work of fixing the spacer ring 4 to the pulley body 3 can be omitted, and the mounting of the spacer ring 4 can be simplified. Furthermore, the thickness for welding or screwing is not required, and the length of the toothed pulley 1 in the belt width direction can be shortened by making the spacer ring 4 thinner.

  The spacer ring 4 can be attached to the pulley body 3 in advance, but when the toothed belt 2 is assembled by adopting a configuration in which the flange 5 is screwed to the small diameter portion 10 at the end of the pulley body 3. Alternatively, the spacer ring 4 may be attached. Specifically, first, the rear split belt 2a is assembled to the pulley body 3 to which the rear flange 5 is fixed, then the spacer ring 4 is mounted, and the front split belt 2b is assembled to the front side. Screw the flange 5 on. As a result, the spacer ring 4 does not interfere with the assembly of the toothed belt 2.

  When a thrust acts on the divided belts 2a and 2b, the spacer ring 4 pushed in the belt width direction by one divided belt 2a pushes the other divided belt 2b as it is and pushes back one divided belt 2a by its reaction. . Thereby, it is not necessary to endure the force which spacer ring 4 itself receives from the division | segmentation belt 2a, and the spacer ring 4 can be made thin by that much. The other split belt 2 b pushed by the spacer ring 4 is restricted from moving in the belt width direction by the flange 5.

  In addition, this invention is not limited to said embodiment, A change can be suitably added within the scope of the present invention. For example, as shown in FIG. 2, instead of the spacer ring 4 having a circular center hole 9, a spacer ring 13 having a tooth profile 12 fitted to the pulley teeth 7 may be disposed on the periphery of the center hole 11. it can. Thereby, a contact area with the division | segmentation belts 2a and 2b can be enlarged, and a contact pressure can be reduced.

  The toothed belt 2 may be divided not only into two parts but also divided into three or more parts, and a plurality of spacer rings 4 and 13 may be interposed between the divided belts. Further, a sliding ring that is slidable in the rotational direction may be mounted between the split belts 2a and 2b and the flange 5 to prevent wear due to friction between the split belts 2a and 2b and the flange 5. .

It is a figure which shows the toothed pulley which concerns on this invention, (a) lower half is side view, upper half is AA sectional drawing, (b) lower half is front view, upper half is BB sectional drawing. Figure It is a figure which shows another form toothed pulley, (a) lower half is side view, upper half is CC sectional drawing, (b) lower half is front view, upper half is DD section. Figure A perspective view of a conventional belt drive device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Toothed pulley 2 Toothed belt 2a, 2b Split belt 3 Pulley body 4, 13 Spacer ring 7 Pulley tooth 9,11 Center hole 12 Tooth shape

Claims (4)

A toothed pulley used by winding a plurality of divided toothed belts in the belt width direction, the pulley body having pulley teeth formed on the outer peripheral surface, and disposed on the outer peripheral side of the pulley body And a spacer ring interposed between adjacent split belts in the belt width direction, wherein the spacer ring is connected to the pulley body in the belt width direction so that thrust received from one split belt can be transmitted to the other split belt. A toothed pulley which is externally fitted to be freely movable.   The toothed pulley according to claim 1, wherein the spacer ring is movable in a rotation direction with respect to the pulley body.   The toothed pulley according to claim 2, wherein a central hole of the spacer ring is a circular hole having a diameter larger than that of the tip of the pulley tooth.   The toothed pulley according to claim 1, wherein the spacer ring is formed with a tooth profile that fits to a pulley tooth at a peripheral edge of a center hole thereof.

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