Patent Description:
In a loom, a warp delivered from a delivery beam is guided toward a cloth fell with being wound on a tension roll. In order to relieve variation in tension caused due to an opening motion of the warp, an easing device configured to positively apply an easing motion to the tension roll every cycle of the loom is used. As a drive means of the casing device, a crank-type drive device is generally used. PTL <NUM> discloses the crank-type drive device.

In addition, the crank-type drive device that is used for a loom is used not only for the easing device but also for an opening device for a loom disclosed in PTL <NUM> and for a terry motion mechanism for a pile loom disclosed in PTL <NUM>.

In addition, the crank-type drive device (hereinafter, referred to as 'conventional device') disclosed in PTL <NUM> includes a crank hub non-rotatably attached to a drive shaft, a holder non-rotatably attached to the crank hub, an eccentric shaft part supported by the holder, and a connecting member rotatably supported by the holder via the eccentric shaft part and a bearing and connected to an easing lever. In the conventional device, the crank hub has a split clamping mechanism as a fixing mechanism, and is attached to the drive shaft by the split clamping mechanism. In addition, the holder is attached in such a form that a surface to be an attached surface is in contact with an end face, which is an attaching surface of the crank hub. Note that, the attaching surface and the attached surface are orthogonal to an axis line of the drive shaft in an attached state.

Note that, in the conventional device, the crank hub is formed in such a form that the split clamping mechanism protrudes from an end face on a side opposite to the attaching surface with respect to a plate-shaped flange part including the attaching surface. In addition, the crank hub is attached to the drive shaft in a direction in which the split clamping mechanism is positioned closer to the tip end-side of the drive shaft than the flange part. For this reason, in the conventional device configured in this way, a problem that a motion of the drive target member is made to be different from a desired motion due to bending of the drive shaft may occur.

More specifically, a case where the conventional device is used for the easing device for a loom is described. The drive shaft is rotatably supported on a loom frame via a bearing and is provided to protrude from the loom frame. In a case where the conventional device is configured as described above, the drive shaft should have a length dimension protruding from the loom frame so that at least the flange part of the crank hub and the holder can be arranged between a position in which the split clamping mechanism of the crank hub is fixed and the loom frame in an axis line direction of the drive shaft. As a result, in the conventional device, a dimension (run length) of the drive shaft from a part supported by the bearing to a part to which the crank hub is fixed is large.

Note that, in the above, the conventional device is connected to the tension roll via the connecting member and the like. Therefore, the tension of the warp applied to the tension roll is applied to the conventional device via the connecting member and the like, and the force thereof is applied to the drive shaft via the holder and the crank hub. The force acts in a direction of bending the drive shaft at the part as a fulcrum supported by the bearing. Accordingly, when the run length is large as described above, the drive shaft may be bent. In particular, in a case of a loom configured to weave a wide woven fabric, a high-density woven fabric for industrial materials, and the like, the force applied to the drive shaft is greater, so that the drive shaft may be more bent.

When the drive shaft is bent, a relationship between a rotating phase of the drive shaft and a position of the tension roll during a periodic easing motion deviates, so that the actual motion of the tension roll may differ from an expected motion (desired motion). Note that, the deviation amount corresponds to the bending of the drive shaft, and the weaving is badly influenced depending on a magnitude of the deviation, so that a quality of the woven fabric to be woven may be lowered.

The present invention has been made in view of the crank-type drive device for a loom of the related art, and an object thereof is to provide a loom with a configuration of the crank-type drive device making it difficult for the drive shaft to be bent, which causes the above-described problems.

The problem as described above is solved by providing a loom comprising: a crank-type drive device according to claim <NUM>.

In the loom comprising the crank-type drive device of the present invention, the crank-type drive device may be configured so that a presence range of the fixing mechanism of the crank hub and a presence range of the bearing overlap each other in an axis line direction of the drive shaft.

According to the present invention, in the crank-type drive device comprised in a loom having the preamble as described above, the crank hub to which the holder is attached in a state where the attaching surface of the attaching part is in contact with the attached surface of the holder is configured so that the fixing mechanism is positioned on the attaching surface-side of the attaching part in the plate thickness direction. Thereby, in the crank-type drive device, the position of the fixing mechanism on the crank hub is closer to the side on which the drive shaft is supported by the bearing than the attached surface of the holder with respect to the axis line direction. As a result, a distance in the axis line direction from the part of the drive shaft to which the crank hub is fixed, in other words, from the part of the drive shaft to which the force from the drive target member is applied to the part of the drive shaft supported by the bearing is shortened. Specifically, the run length on the drive shaft is shortened. Thereby, in the crank-type drive device, the bending is less likely to occur on the drive shaft to which the force from the drive target member is applied, as compared to the conventional device configured as described above. Therefore, according to the crank-type drive device of the present invention, the bending of the drive shaft, which causes the above-described problems, is more difficult to occur.

In the loom comprising the crank-type drive device of the present invention, the crank-type drive device is configured so that the presence range of the fixing mechanism of the crank hub and the presence range of the bearing overlap each other in the axis line direction of the drive shaft. Thereby, the run length on the drive shaft is further shortened. Thereby, in the crank-type drive device, the bending of the drive shaft is more difficult to occur, so that it is possible to prevent occurrence of the problems more securely.

Hereinafter, an embodiment (the present embodiment) of the crank-type drive device of the present invention will be described with reference to <FIG>. Note that, the present embodiment shows an example where the present invention is applied to an easing device for a loom, as shown.

As shown in <FIG> and <FIG>, in a loom, a warp T delivered from a warp beam <NUM> is guided toward a cloth fell with being wound on a tension roll <NUM>. The easing device <NUM> includes a pair of easing levers <NUM> and <NUM> configured to support the tension roll <NUM> at both ends, crank-type drive devices (hereinafter, simply referred to as 'drive devices') <NUM> and <NUM> each provided in correspondence to each of the easing levers <NUM> and configured to swing the corresponding easing lever <NUM>, and rods <NUM> and <NUM> and arms <NUM> and <NUM> for connecting each of the easing levers <NUM> and each of the corresponding drive devices <NUM> each other.

Among them, each easing lever <NUM> is rotatably supported by a loom frame <NUM> via a support shaft <NUM> inserted and fitted in a support hole 12A formed at one end portion of the easing lever. The tension roll <NUM> is supported by both the easing levers <NUM> and <NUM> in such a form that shaft parts 7a at both ends are inserted and fitted in support holes 12B formed at intermediate parts of the easing levers <NUM>. Therefore, the tension roll <NUM> is supported to be swingable about a shaft center of the support shaft <NUM> with respect to the loom frame <NUM>, via each easing lever <NUM>.

In addition, the other end portion of each easing lever <NUM> is formed with a support hole 12C, and a shaft member <NUM> is inserted and fitted in the support hole 12C. Each easing lever <NUM> is connected to the arm <NUM> via the shaft member <NUM>. In addition, the arm <NUM> is connected to the drive device <NUM> via a rod <NUM>. Specifically, each easing lever <NUM> is connected to the corresponding drive device <NUM> via the shaft member <NUM>, the arm <NUM> and the rod <NUM>.

As shown in <FIG> and <FIG>, each drive device <NUM> includes a crank hub <NUM> non-rotatably attached to a drive shaft <NUM>, a holder <NUM> non-rotatably attached to the crank hub <NUM>, an eccentric shaft part <NUM> supported by the holder <NUM>, and a connecting member <NUM> rotatably supported by the holder <NUM> via the eccentric shaft part <NUM> and a bearing <NUM> and connected to the corresponding rod <NUM>.

Note that, the drive shaft <NUM> is rotatably supported by the loom frame <NUM> via a bearing, and is provided so that one end thereof protrudes outward from the loom frame <NUM> in a width direction (weaving direction) of the loom. In addition, the drive shaft <NUM> is connected to a main shaft (not shown) of the loom via a drive transmission mechanism, and is configured to rotate in synchronization with the main shaft.

The crank hub <NUM> includes a shaft-shaped shaft part 22a having a through-hole 22c in which the drive shaft <NUM> is inserted and fitted, and a plate-shaped attaching part 22b for attaching the holder <NUM>. The through-hole 22c of the shaft part 22a is formed so that a center thereof matches a shaft center L1 of the shaft part <NUM>. In addition, the shaft part 22a is provided with a fixing mechanism for fixing the crank hub <NUM> to the drive shaft <NUM> inserted and fitted in the through-hole 22c. In the present embodiment, the fixing mechanism is a split clamping mechanism 22a1 having a slot configured to communicate with the through-hole 22c.

In the crank hub <NUM>, the attaching part 22b has a plate shape as described above, and is formed integrally with the shaft part 22a on one end-side in an axis line direction of the shaft part 22a in such a form that a plate thickness direction thereof is matched with the axis line direction of the shaft part 22a. Note that, the attaching part 22b is also formed with a through-hole 22f configured to communicate with the through-hole 22c of the shaft part 22a. The through-hole 22f is formed so that the drive shaft <NUM> inserted and fitted in the through-hole 22c can be inserted therein. In addition, the attaching part 22b is formed with three insertion holes <NUM> penetrating in the plate thickness direction and provided so as for fixing bolts <NUM> for attaching the holder <NUM> to the crank hub <NUM> to be inserted therein.

As for the holder <NUM> and the eccentric shaft part <NUM>, in the present embodiment, both the holder <NUM> and the eccentric shaft part <NUM> are integrally formed. Specifically, the holder <NUM> has a substantial plate shape so as to be attached to the plate-shaped attaching part 22b of the crank hub <NUM>. In addition, the eccentric shaft part <NUM> is formed integrally with the holder <NUM> in a form of protruding from one end face of the holder <NUM> in the plate thickness direction. In this way, in the present embodiment, the holder <NUM> and the eccentric shaft part <NUM> are integrally formed, so that the eccentric shaft part <NUM> (eccentric shaft) is supported by the holder <NUM>.

In addition, the eccentric shaft part <NUM> is formed with a through-hole 25b for inserting the drive shaft <NUM> in such a form that a center thereof is matched with a shaft center L2 of the eccentric shaft part <NUM>. The holder <NUM> is also formed with a through-hole 24b configured to communicate with the through-hole 25b of the eccentric shaft part <NUM>. However, the through-hole 24b is formed as a hole having an inner diameter greater than an inner diameter of the through-hole 25b.

As for the crank hub <NUM>, the holder <NUM> and the eccentric shaft part <NUM> configured as described above, the crank hub <NUM> is non-rotatably attached to the drive shaft <NUM> in such a form that a portion on a tip end-side of the part of the drive shaft <NUM> protruding from the loom frame <NUM> is inserted and fitted in the through-hole 22c. Note that, the attaching of the crank hub <NUM> to the drive shaft <NUM> is performed by clamping fixing by the split clamping mechanism 22a1. Therefore, the crank hub <NUM> can be attached to the drive shaft <NUM> while freely changing a phase.

In addition, the holder <NUM> and the eccentric shaft part <NUM> are provided in a form that the drive shaft <NUM> is inserted in the through-hole 25b and the through-hole 24b in a direction in which the eccentric shaft part <NUM> is positioned on the loom frame <NUM>-side with respect to the holder <NUM>, on a side of the loom frame <NUM> facing toward the crank hub <NUM>. Therefore, the holder <NUM> faces the crank hub <NUM> on an end face (the other end face) on an opposite side to a side on which the eccentric shaft part <NUM> protrudes in the plate thickness direction. In addition, the holder <NUM> is attached to the crank hub <NUM> in a state where the other end face is in contact with the attaching part 22b of the crank hub. Therefore, the other end face of the holder <NUM> becomes an attached surface 24e that is attached to the crank hub <NUM>.

Note that, the attaching of the holder <NUM> to the crank hub <NUM> is performed using the fixing bolts <NUM>. More specifically, the holder <NUM> is formed with female thread holes (not shown) configured to open to the attached surface 24e and provided for screwing the fixing bolts <NUM> in positions corresponding to the three insertion holes <NUM> of the crank hub <NUM>. In a state where the holder <NUM> is in contact with the attaching part 22b of the crank hub <NUM> on the attached surface 24e, each of the fixing bolts <NUM> inserted into each of the insertion holes <NUM> of the crank hub <NUM> from the tip end-side of the drive shaft <NUM> is screwed into the corresponding female thread hole of the holder <NUM>, so that the holder <NUM> is attached to the crank hub <NUM>.

The eccentric shaft part <NUM> formed integrally with the holder <NUM> attached to the crank hub <NUM> in this way is connected to the rod <NUM> on the tension roll <NUM>-side, which is a drive target member, via the connecting member <NUM>. The connecting member <NUM> is a member having an annular part, and is fitted to the eccentric shaft part <NUM> via the bearing <NUM> at the annular part. Therefore, the connecting member <NUM> is rotatably supported by the holder <NUM> via the eccentric shaft part <NUM>. Note that, in a state where the bearing <NUM> is inserted and fitted in the eccentric shaft part <NUM>, one end face of the bearing <NUM> in the axis line direction is in contact with the holder <NUM>.

In the drive device <NUM> that is a crank-type drive device, the drive device <NUM> should be configured so that the shaft center L2 of the eccentric shaft part <NUM> to which the rod <NUM> is connected is eccentric with respect to the shaft center L1 of the drive shaft <NUM>. On the other hand, the drive shaft <NUM> is inserted in the through-hole 25b of the eccentric shaft part <NUM> as described above. Therefore, the through-hole 25b of the eccentric shaft part <NUM> is formed as a hole having an inner diameter by which the desired eccentric state of the eccentric shaft part <NUM> with respect to the drive shaft <NUM> is implemented, with respect to the shaft diameter of the drive shaft <NUM>.

In addition, the drive device <NUM> of the present embodiment is configured so that an attaching position of the holder <NUM> to the crank hub <NUM> can be adjusted so as to adjust eccentricity of the shaft center L2 of the eccentric shaft part <NUM> with respect to the shaft center L1 of the drive shaft <NUM>. More specifically, each insertion hole <NUM> of the crank hub <NUM> is formed as an elongated hole that is long in a direction (eccentric direction) connecting the shaft center L1 of the drive shaft <NUM> and the shaft center L2 of the eccentric shaft part <NUM> in a state where the crank hub <NUM> and the holder <NUM> are attached to each other, as seen in the axis line direction of the drive shaft <NUM>. Therefore, when attaching the holder <NUM> to the crank hub <NUM> by using the fixing bolts <NUM>, the attaching position can be adjusted within a range of each insertion hole <NUM> that is an elongated hole.

In the drive device <NUM>, the crank hub <NUM> that is attached to the drive shaft <NUM> on a side closer to the tip end of the drive shaft <NUM> than the holder <NUM> is attached to the drive shaft <NUM> in a direction in which the shaft part 22a having the split clamping mechanism 22a1 is positioned on the loom frame <NUM>-side with respect to the attaching part 22b. Thereby, the holder <NUM> is attached to the crank hub <NUM> in a state where the attached surface 24e is in contact with an end face on a side, on which the shaft part 22a protrudes, of the attaching part 22b of the crank hub <NUM>. Therefore, the end face of the attaching part 22b with which the holder <NUM> is in contact becomes an attaching surface 22d of the crank hub <NUM>.

In this way, in the drive device <NUM>, the crank hub <NUM> is configured so that the attaching surface 22d, to which the holder <NUM> is attached, is to be an end face on a side, on which the shaft part 22a protrudes, of the attaching part 22b. In addition, the crank hub <NUM> is attached to the drive shaft <NUM> in a state where the attaching surface 22d faces toward the loom frame <NUM> so that the holder <NUM> arranged on the loom frame <NUM>-side with respect to the attaching part 22b is attached to the crank hub <NUM> in a state of being in contact with the attaching surface 22d. The crank hub <NUM> is attached to the drive shaft <NUM> and the holder <NUM> is attached to the crank hub <NUM> in this way, so that the split clamping mechanism 22a1 as a fixing mechanism is positioned closer to the loom frame <NUM>-side than the attached surface 24e of the holder <NUM>.

Note that, in the present embodiment, the shaft part 22a of the crank hub <NUM> is formed so that a dimension in the axis line direction (the axis line direction of the drive shaft <NUM>) is greater than a dimension in the plate thickness direction of the holder <NUM>. Thereby, in the state (attached state) where the holder <NUM> is attached to the crank hub <NUM>, as described above, a position of the end face on the other end-side of the shaft part 22a is within a presence range of the eccentric shaft part <NUM> positioned closer to the loom frame <NUM> than the holder <NUM> with respect to the axis line direction. Specifically, in the above configuration, the presence range of the shaft part 22a and the presence range of the eccentric shaft part <NUM> overlap in the axis line direction. Since the bearing <NUM> is fitted to the eccentric shaft part <NUM>, as described above, a presence range of the bearing <NUM> and the presence range of the shaft part 22a overlap in the axis line direction. Therefore, the inner diameter of the through-hole 25b of the eccentric shaft part <NUM> is formed greater than the outer diameter of the shaft part 22a.

In addition, the split clamping mechanism 22a1 of the shaft part 22a includes the slot 22a2, as described above, and also includes a protruding portion 22a5 protruding from an outer peripheral surface of the shaft part 22a in a position continuing to the slot 22a2, and a bolt 22a4 for split clamping that is screwed to the protruding portion 22a5. The slot 22a2 is formed over the axis line direction of the shaft part 22a. Specifically, the split clamping mechanism 22a1 as the fixing mechanism is present over the presence range of the shaft part 22a with respect to the axis line direction. Therefore, in the configuration of the present embodiment, the presence ranges of the split clamping mechanism 22a1 (fixing mechanism) and the bearing <NUM> overlap each other in the axis line direction of the drive shaft <NUM>.

Note that, in the split clamping mechanism 22a1, the protruding portion 22a5 of the shaft part 22a is formed to continue from the one end-side of the shaft part 22a and is also formed within a range in which it enters the through-hole 24b of the holder <NUM> in the attached state, with respect to the axis line direction. Therefore, in the attached state, the protruding portion 22a5 is positioned in the through-hole 24b of the holder <NUM>. In addition, the bolt 22a4 for split clamping that is screwed to the protruding portion 22a5 is also positioned in the through-hole 24b of the holder <NUM>, in the attached state.

Additionally describing, in the present embodiment, the screwing direction of the bolt 22a4 for split clamping to the protruding portion 22a5 is orthogonal to the axis line direction, like the general split clamping mechanism. Further, in the attached state, the direction of the slot 22a2, as seen in the axis line direction, coincides with the eccentric direction. Therefore, the screwing direction of the bolt 22a4 for split clamping is orthogonal to the eccentric direction, as seen in the axis line direction.

In addition, as shown in <FIG>, the attaching part 22b of the crank hub <NUM> is formed so that the bolt 22a4 for split clamping is exposed, as seen in the axis line direction, so as to enable an operation on the bolt 22a4 for split clamping positioned closer to the loom frame <NUM> than the attaching part 22b from the tip end-side of the drive shaft <NUM> in the attached state. Specifically, a portion of the attaching part 22b has such a shape that is matched with a portion on a side of the protruding portion 22a5, on which the bolt 22a4 for split clamping is inserted, as seen in the axis line direction.

Also, the through-hole 24b of the holder <NUM> is formed to have an enlarged portion 24J where a portion facing a head portion of the bolt 22a4 for split clamping in the attached state and a surrounding thereof are enlarged in a direction (the screwing direction of the bolt 22a4 for split clamping) orthogonal to the eccentric direction so as to enable accommodation of the split clamping mechanism 22a1 (the protruding portion 22a5, the bolt 22a4 for split clamping) provided for the shaft part 22a as described above. In addition, the enlarged portion 24J is formed to have such a dimension that the bolt 22a4 for split clamping can be operated in the attached state by a tool.

Further, in the present embodiment, in order to guide movement of the holder <NUM> and the eccentric shaft part <NUM> in the eccentric direction with respect to the crank hub <NUM>, a pair of guide surfaces 22e and 22e is formed on the outer peripheral surface of the shaft part 22a of the crank hub <NUM>, and a pair of engaging surfaces 25f and 25f to engage with the pair of guide surfaces 22e and 22e is formed on the eccentric shaft part <NUM>.

More specifically, the shaft part 22a of the crank hub <NUM> has two parallel planar surfaces 22e and 22e formed by cutting portions of an outer peripheral surface of an end portion on the other end-side of the shaft part. However, directions of the planar surfaces 22e match the direction (=the eccentric direction) of the slot 22a2 of the split clamping mechanism 22a1, as seen in the axis line direction. The planar surfaces 22e function as guide surfaces of the shaft part 22a.

In addition, the eccentric shaft part <NUM> is formed so that a part, which faces each guide surface 22e of the shaft part 22a in the attached state, of an inner peripheral surface of the through-hole 25b is to be a planar surface 25f parallel to each guide surface 22e in the attached state. Further, the through-hole 25b is formed so that the parts at which the planar surfaces 25f are formed further protrude inwardly than the other part so that an interval between the two planar surfaces 25f and 25f is substantially the same as an interval between the two guide surfaces 22e and 22e of the shaft part 22a. Thereby, in the attached state, each guide surface 22e of the shaft part 22a is engaged with the facing planar surface 25f of the through-hole 25b, and the planar surfaces 25f function as the engaging surfaces of the eccentric shaft part <NUM>. In a state where each fixing bolt <NUM> is unfastened, each engaging surface 25f of the eccentric shaft part is engaged and sliding contacted to the corresponding guide surface 22e of the shaft part 22a, thereby guiding movement of the holder <NUM> in the eccentric direction.

As described above, in the crank-type drive device <NUM>, the crank hub <NUM> is configured so that the split clamping mechanism 22a1 is positioned on the attaching surface 22d-side of the attaching part 22b <NUM> in the plate thickness direction. Therefore, the crank-type drive device <NUM> is configured so that the split clamping mechanism 22a1 is positioned closer to a side (the loom frame <NUM>-side), on which the drive shaft <NUM> is supported by the bearing <NUM>, than the attached surface 24e of the holder 24e with respect to the axis line direction, in the attached state.

As a result, the run length of the drive shaft <NUM>, which is a distance in the axis line direction from the part of the drive shaft <NUM> to which the crank hub <NUM> is fixed to the part of the drive shaft <NUM> supported by the bearing <NUM>, is shorter than the conventional configuration where the split clamping mechanism is positioned closer to the tip end-side of the drive shaft <NUM> than the attached surface 24e of the holder <NUM> in the attached state. Thereby, in the crank-type drive device <NUM>, the bending is less likely to occur on the drive shaft <NUM> that receives the force from the tension roll <NUM>, which is a drive target member.

In addition, the crank-type drive device <NUM> is configured so that the presence range of the split clamping mechanism 22a1 of the crank hub <NUM> and the presence range of the bearing <NUM> fitted to the eccentric shaft part <NUM> overlap in the axis line direction, as described above. Thereby, the crank-type drive device <NUM> is configured so that the run length of the drive shaft <NUM> is shorter and the bending is less likely to occur on the drive shaft <NUM>.

In the above, one embodiment of the crank-type drive device for a loom of the present invention has been described. However, the crank-type drive device for a loom of the present invention is not limited to the above embodiment, and can also be implemented in following modified forms.

Claim 1:
A loom comprising:
a crank-type drive device (<NUM>);
a drive shaft (<NUM>) configured to drive the crank-type drive device (<NUM>); and
a drive target member (<NUM>) configured to be driven by the crank-type drive device (<NUM>),
the crank-type drive device (<NUM>) including:
a crank hub (<NUM>) non-rotatably attached to a drive shaft (<NUM>);
a holder (<NUM>) non-rotatably attached to the crank hub (<NUM>);
an eccentric shaft (<NUM>) supported by the holder (<NUM>); and
a connecting member (<NUM>) rotatably supported by the holder via the eccentric shaft (<NUM>) and a bearing (<NUM>) and connected to the drive target member (<NUM>),
the holder (<NUM>) including an attached surface (24e) that is attached to the crank hub (<NUM>), is orthogonal to an axis line of the drive shaft (<NUM>) and is a surface facing toward a tip end of the drive shaft (<NUM>),
the crank hub (<NUM>) including a plate-shaped attaching part (22b) which the attached surface (24e) of the holder (<NUM>) is attached thereto and has an attaching surface (22d) in contact with the attached surface, and a fixing mechanism (22a1) for fixing the crank hub (<NUM>) to the drive shaft (<NUM>), the drive shaft being inserted and fitted in the fixing mechanism,
characterized in that
the crank hub (<NUM>) is configured so that the fixing mechanism (22a1) is positioned on the attaching surface (22d)-side of the attaching part (22b) in a plate thickness direction.