JP4569804B2 - Bidirectional rotating damper - Google Patents

Description

  The present invention relates to a bi-directional rotary damper that uses a frictional force between relatively rotating braking members, and in particular, the frictional force can be adjusted according to a change in temperature environment, and rotation unevenness is less likely to occur. The present invention relates to a bi-directional rotating damper that can stably exhibit a damper force.

  In recent years, in a large-scale construction site using a large crane, as shown in FIG. 12, for example, a camera is attached near the tip of the jib, and an image captured by this camera is displayed on a monitor in front of the operator and suspended. A method is adopted in which a crane is operated while grasping the direction of a conveyed product and the positional relationship with a building with a monitor. At this time, no matter what the angle of the jib changes, the camera needs to face the direction of the transported object that is suspended from the tip of the jib, and it must not be staggered in order to obtain a stable image. There is. In order to prevent this wobbling, a bi-directional rotating damper is used between the camera side bracket and the jib side bracket.

Conventionally, an oil damper in which a viscous fluid is sealed is used as a rotary damper used in such applications. An oil seal is used for the oil damper in order to prevent oil leakage (see Patent Document 1).

In addition, as a bi-directional rotating damper, a multi-plate rotating damper using shearing resistance of viscous liquid generated between a plurality of relatively rotating movable plates and a plurality of fixed plates has been proposed (see Patent Document 2). .
JP 2001-108004 A Japanese Patent Laid-Open No. 4-50524

  In the above application, the damper supports the load of the camera at the outer end portion of the rotating shaft. For this reason, in the oil damper as shown in Patent Document 1, whenever the crane jib swings greatly, the load applied to the outer end portion causes the rotation shaft to bend, and the oil seal around the rotation shaft functions sufficiently. As a result, oil leaks from the seal portion or air flows into the viscous fluid chamber, resulting in a problem that the damper torque decreases or becomes unstable, and the monitor image is disturbed. In addition, every time such a problem occurs, repairs and maintenance such as removing oil by filling with oil are necessary, which hinders stable work. In addition, the oil in the sealed chamber expands and contracts with changes in the temperature environment, and an accumulator is required to cope with this. For this reason, the structure becomes complicated and expensive.

  On the other hand, the multi-plate rotary damper disclosed in Patent Document 2 has a structure in which the movable plate and the fixed plate are fixed in the axial direction and held in the casing in close contact with each other, so that fine adjustment of the rotational torque cannot be easily performed. It has become.

  Therefore, the present invention was created in view of the existing circumstances as described above, and employs a system that generates a damper force mainly by the frictional force between the braking members, repairs due to oil leakage, etc., oil replenishment It is an object of the present invention to provide a low-cost bi-directional rotating damper that does not require maintenance, etc., can sufficiently respond to changes in the temperature environment, can exhibit a smooth damper operation, and is inexpensive.

In the present invention, the casing 1, the shaft member 4 rotatable relative to the casing, and the shaft 1 are disposed on the shaft member 4 in the casing 1, and at least of the conical concave surface and the conical convex surface. A first braking member 2 that has one side and is fixed to either the casing 1 or the shaft member 4; and the conical concave surface of the first braking member 2 that is disposed on the shaft member 4 in the casing 1 And a second braking member having at least one of a conical convex surface and a conical concave surface opposed to and at least one of the conical convex surfaces and fixed to the other of the casing 1 and the shaft member 4; And forming one or both of the first braking member 2 and the second braking member 3 with a resin, and providing a plurality of adjustment grooves from the outer peripheral end toward the center, the first braking member 2 and the second braking member 3 the braking member 3, the opposing surface While contacting with the peripheral portion, so that the gap gradually widened toward the center is formed between the two facing surfaces, constructed with different respective tilt angles, the first brake member and the second brake member And a gap adjusting means for adjusting the gap between the opposed surfaces by relatively moving in the axial direction.

The casing has a configuration in which both ends are closed by an end wall having at least one end cap as a separate end cap, and the first braking member is configured to have conical concave surfaces on both sides in the axial direction and fixed to the shaft member. The second braking member is composed of a pair of members having conical convex surfaces opposite to the conical concave surfaces on both axial sides of the first braking member, and each of the pair of members is an end wall at both ends of the casing. And the end cap is configured to be movable with respect to the casing and to be fixed at an arbitrary position in the moving process, thereby forming the gap adjusting means.
A non-flowable lubricant is interposed between the opposing surfaces of the first braking member 2 and the second braking member 3.
At least a portion of the first braking member 2 and / or the second braking member 3 constituting the facing surface is formed of a synthetic resin material having a low friction coefficient.

  Since the present invention is configured as described above, there is no need for an oil seal or the like, and maintenance such as repair due to oil leakage or oil replenishment is unnecessary. In addition, since there is no sealed oil chamber, an accumulator is not required even if the oil or components expand or contract due to changes in the temperature environment, the structure is simplified, and the cost can be reduced. Furthermore, in the case of torque fluctuation due to changes in the temperature environment depending on the region or season, the frictional force between the two braking members is changed by adjusting the gap between the first braking member and the second braking member, so that the shaft member 4 The rotational torque can be optimized.

In particular, the one or both of the first braking member 2 and the second brake member 3, so to form a plurality of tone Seimizo 6 extending toward the center from the outer peripheral end, the brake member by operating the clearance adjustment means The portion adjacent to the adjustment groove 6 bends to change the inclination angle of the inclined surface having a conical shape, thereby easily adjusting the rotational torque of the shaft member 4 by expanding or reducing the contact area between both braking members. be able to.

  Further, since a lubricant such as non-flowing grease is interposed between the opposing surfaces of the first braking member 2 and the second braking member 3, the first braking member 2 and the second braking member 3 In the meantime, it becomes possible to generate a damper force due to the shear resistance force of a lubricant such as grease in addition to the frictional force, and to maintain a smooth contact without sticking. The lubricant such as non-flowing grease used here does not cause problems such as oil leakage unlike the fluid oil filled and sealed in the casing in a so-called oil damper.

  Furthermore, since at least the facing surface portion of either one or both of the first braking member 2 and the second braking member 3 is formed of a synthetic resin material having a low friction coefficient, the first braking member 2 and the second braking member 2 A smoother contact with the member 3 can be maintained.

  Note that the reference numerals added in the means for solving the above-described problems and the effects of the invention are given for easy reference to the parts showing the components shown in the drawings. However, the present invention is not limited to the structure / shape indicated by the reference numeral.

  The first best mode for carrying out the present invention will be described below with reference to the drawings. Reference numeral 1 shown in the figure indicates a cylindrical casing of a bi-directional rotating damper according to the present invention. 1 and 2, the casing 1 is screwed to a U-shaped bracket Q attached to a crane jib at a plurality of locations. A shaft member 4 that is rotatable relative to the casing 1 extends along the axis of the casing 1, and both ends of the shaft 1 that protrude from both sides of the casing 1 are attached to a U-shaped bracket R so as not to rotate relative to the casing 1. . A case P accommodating a camera is fixed to the bracket R.

3, 4, and 5 are a front view, a left side view, and a right side view, respectively, of the bidirectional rotary damper according to the present invention. The rotation of the shaft member 4 with respect to the bracket R is performed by a key (not shown) held in the key groove 10 at the left end in FIG. 3 and by the cut 11 at the right end.

In the left side surface of the casing 1 shown in FIG. 4, a disc-shaped end cap 5 is shown inside the peripheral flange 1 </ b> A, and a central portion thereof is formed integrally with the end cap 5. Hexagon nut 5A. Around the hexagonal nut 5A, a bolt 9 for fixing a pad, which is a second braking member described later, to the end cap 5 is disposed. A pair of stopper screws 7 for fixing the end cap 5 to the flange 1A are indicated by dotted lines in the peripheral flange 1A, and in the vicinity thereof, the casing 1 is attached to a jib of a crane. This is a bolt insertion hole 12 for fixing to the square bracket Q. The reason why the insertion holes 12 are one each on the left and right sides is that consideration is given to the use of a tool that is locked to the hexagonal nut 5A in order to turn the end cap 5.

On the right side surface of the casing 1 shown in FIG. 5, all except the bolt 9 that fixes the central shaft member 4 and a pad that is a second braking member described later to the casing 1 are integrally formed. Three bolts shown on the left and right sides of the peripheral flange 1B are bolt insertion holes 12 for fixing the casing 1 to a U-shaped bracket Q attached to a jib of a crane.

As shown in FIG. 6, the casing 1 has one end closed by an end wall 15 and the other end opened, and the open end is closed by an end cap 5 constituting another end wall. Yes. A female screw portion 1C is formed on the inner peripheral surface of the edge of the open end. A male screw portion 5C formed on the outer peripheral surface of the end cap 5 is screwed to the female screw portion 1C, and the end cap 5 is provided so as to be able to advance and retreat along the female screw portion 1C. It is comprised so that it may function as a means. The forward and backward movement of the end cap 5 is performed by twisting a hexagonal nut portion 5 </ b> A that protrudes outward from the center of the end cap 5 with a tool (not shown) such as a spanner or a wrench. Further, the tip of the stopper screw 7 screwed from the outer peripheral surface of the flange 1A along the two screw holes provided in the flange 1A of the casing 1 is formed into an annular recess 5B formed at the edge of the outer peripheral surface of the end cap 5. By locking, the end cap 5 can be fixed at a desired axial position with respect to the casing 1. The shaft member 4 is rotatably inserted into the shaft hole of the hexagon nut portion 5A via the bush 4A. The end cap 5 only needs to be configured so that it can be advanced and retracted by rotation or the like, and the hexagon nut portion 5A is not limited to a hexagon, and various other configurations are conceivable.
In the example of this figure, the casing 1 is configured such that only the other end can be opened by the end cap 5 and the end wall can be moved in the axial direction, but both ends can be opened and the end wall can be moved in the axial direction. It will be easily understood by those skilled in the art that the present invention can be carried out even if it is possible.

  Both ends of the shaft member 4 extend through the both end walls 5 and 15 of the casing 1 to the outside, and rotate with respect to the casing 1 via bushes 16 attached in the shaft holes of the both end walls 5 and 15. It is provided freely. A key groove portion 10 is formed in a portion of the casing 1 that protrudes from the left side of the casing 1 in the drawing, and a D-cut portion 11 is formed in a portion that protrudes from the right side. These 10 and 11 enable the shaft member 4 and the camera P to be integrally rotated relative to the casing 1 after the camera side bracket R is attached to the shaft member 4. The camera-side bracket R is divided into two parts from the center part of the base of the upward U-shape in the figure, and these divided halves are attached to the ends of the shaft member 4 from the left and right, and screws 20 (FIG. It is fixed to the case of the camera P by 1).

  Further, a first braking member 2 having a substantially X-shaped cross section, which is clearly shown in FIG. 7 and having conical concave surfaces 2A on both the left and right sides, is attached to the approximate center of the shaft member 4 in the casing 1. That is, the shaft member 4 is inserted into the shaft hole 2B formed along the shaft gland of the first brake member 2, and the first brake member 2 is disposed substantially at the center of the shaft member 4 in the longitudinal direction. The first braking member 2 is fixed to the shaft member 4 by screwing the bolts 8 from the vertical direction perpendicular to the axis 2 to the position just before the middle of the shaft member 4.

  Further, on the shaft member 4, there is provided a conical convex surface 3A facing the left and right conical concave surfaces 2A of the first braking member 2 and having a substantially complementary relationship therewith, as shown clearly in FIG. A pair of left and right second braking members 3, which are umbrella-shaped pads, are arranged so as to sandwich the first braking member 2. That is, one of the second braking members 3 has its boss portion 3C fixed to the end cap 5 side constituting one end wall of the casing 1 by a plurality of bolts 9, for example, and the other second braking member 3. 3, the boss 3 </ b> C is fixed to the closed end wall 15 of the casing 1 by a plurality of bolts 9, for example. At this time, as shown in FIGS. 4 to 6, the bolt 9 is disposed at a boss portion as close to the center of the second braking member 3 as possible. This is to make it possible to form the adjustment groove 6 to be described later up to a portion close to the center to some extent. For this reason, in FIG. 4, the bolt 9 is disposed at a position where the head portion slightly bites into the peripheral surface of the hexagonal nut portion 5A. The second braking member 3 is made of a synthetic resin material known as a sliding grade having a low coefficient of friction, for example, NW manufactured by Polyplastics Co., Ltd., in order to prevent sticking between the second braking member 3 and the first braking member 2. -02.

  In addition, the inclination angles of the first braking member 2 and the second braking member 3 are set so that a gap is formed between the opposing surfaces of the first braking member 2 and the second braking member 3 at the periphery while gradually expanding toward the center. They are configured differently. Further, non-flowable grease G or the like is interposed between the opposing surfaces of the first braking member 2 and the second braking member 3. The end cap 5 acting in the axial direction with respect to the second braking member 3 so that the gap can be adjusted is used as the gap adjusting means. As will be described below, the gap adjusting means is configured such that the contact area between the opposing surfaces 2A and 3A of the braking members 2 and 3 is centered from the peripheral edge of the conical surface by the forward and backward movement of the end cap 5 into the case sink 1. It is continuously changed in the range up to the vicinity of the part.

  As shown in FIG. 8, the resin-made second braking member 3 has at least three or more, for example, a total of four notch grooves 6 at intervals of 90 ° in the direction from the outer peripheral end to the center portion. It is formed to extend. As a result, when a pressing force is applied by the movement of the end cap 5 that is the gap adjusting means, the second braking member 3 is deformed to narrow the notch groove 6, and the notch groove 6 of the second braking member 3 is formed. The inclination angle of the conical convex surface 3A becomes close to the inclination angle of the conical concave surface 2A of the first braking member 2, and the contact area between the two becomes large. At this time, the reaction force due to the resin deformation of the second braking member 3 also increases on the contact surface. Therefore, the rotational torque of the shaft member 4 can be increased.

In the example shown in FIG. 6, only the second braking member 3 is made of resin, but both the first braking member 2 and the second braking member 3 may be made of resin. The adjustment groove 6 may be a thin groove instead of a notch groove. In short, when a pressing force is applied by the gap adjustment means, the inclination angle of the conical inclined surface of the braking member having the adjustment groove is deformed. Any groove that can be narrowed to allow is acceptable.

  Next, an example of use and operation of the best mode configured as described above will be described. If the torque changes due to changes in the temperature environment resulting in changes in the hardness of the lubricant such as expansion and contraction of parts and non-flowable grease, the nut portion 5A of the end cap 5 in the gap adjusting means is twisted. By engaging the turning tool and turning the end cap 5, the conical concave surface 2A of the first braking member 2 and the conical convex surface 3A of the second braking member 3 that is substantially complementary to the conical concave surface 2A. The gap is adjusted, and the stopper screw 7 is tightened and fixed at a desired position. At this time, the second braking member 3 has a conical concave surface 2A of the first braking member 2 and a conical convex surface 3A of the second braking member 3 by the notch groove 6 at a portion adjacent to the notched groove 6 of the conical convex surface 3A. It is easy to sink in, and the axial action by the gap adjusting means can be performed continuously and variably, so that the gap can be finely adjusted. By changing the frictional force between the braking members 2 and 3 and the shear resistance force such as non-flowing grease, the rotational torque of the shaft member 4 can be easily and continuously adjusted, and a synthetic resin having a low friction coefficient. The opposing surface portion formed of the material can cope with torque fluctuations due to changes in the temperature environment depending on the region and season.

Next, a second best mode for carrying out the present invention will be described with reference to FIG. In this embodiment, instead of fastening and fixing the second braking member 103 fixed to the end wall 115 on one end side of the casing 101 and the end cap 105 which is the end wall on the other end side with the bolt, the second braking member 103 The protrusion 103D is provided on the outer surface side of the boss portion 103C of the casing 101, the recesses 105C and 115C are formed in the both end walls 105 and 115 of the casing 101, respectively, and the protrusion 103D is fitted into the recesses 105C and 115C. 103 is fixed with respect to the rotation direction.
With such a configuration, the boss portion of the second braking member 103 can have a small diameter, and accordingly, the length of the adjustment groove 6 formed in the radial direction from the outer peripheral surface of the second braking member 103. The boss portion can be made longer by the smaller diameter, and the variable angle of the second braking member 103 or the inclination angle adjustment width of the portion adjacent to the adjustment groove 6 of the conical inclined surface, and hence the adjustment width of the damper force can be increased. Can be bigger.

  Next, a third best mode for carrying out the present invention will be described with reference to FIG. In this embodiment, the first braking member 202 fixed to the shaft member 204 with a bolt 208 has a conical concave surface 202A having an acute inclination angle only on one side thereof. The surface opposite to the conical concave surface 202A of the first braking member 202 is a flat end surface, and is brought into contact with the inner surface of the corresponding end wall 215 of the casing 201 via a flat donut-shaped spacer member 217 having a low friction coefficient. ing. The second braking member 203 rotatably provided on the shaft member 204 has an acute-angled conical shape opposed to the conical concave surface 202A of the first braking member 202 via a gap G formed in the vicinity of the center only on one surface thereof. It has a convex surface 203A, and a boss portion 203C is formed on the opposite surface. The boss portion 203 </ b> C has a projection 203 </ b> D at the outer end portion, and the projection 203 </ b> D is fitted into a recess 205 </ b> C formed in the end cap 205 to fix the second braking member 203 to the casing 201 so as to be integrally rotatable. In this embodiment, the contact area can be increased by making the mutual angle between the conical concave surface 202A of the first braking member 202 and the conical convex surface 203A of the second braking member 203 acute. The gap adjustment width is increased.

  Next, a fourth best mode for carrying out the present invention will be described with reference to FIG. In this embodiment, the first braking member 302 fixed to the shaft member 304 by the bolt 308 is formed with a thick width, and conical concave surfaces 302A on the left side and conical convex surfaces 302B on the right side are respectively formed on both side surfaces thereof. Is formed. On both sides of the first braking member 302, a member having a conical convex surface 303A facing the conical concave surface 302A on the left side through a gap G formed in the vicinity of the center, and a conical convex surface 302B on the right side in the vicinity of the center. A pair of second braking members 303 including members having conical concave surfaces 302 </ b> A that face each other with a gap G formed therebetween are provided. The second braking member 303 is rotatable with respect to the shaft member 304 and is fixed to the end cap 305 and the right end wall 315, which are the left end wall of the casing 301, with bolts 309, respectively. The present invention can take such an embodiment as occasion demands.

  The bi-directional rotary damper according to the present invention is mainly used when a work for transferring while monitoring a heavy object suspended on a crane hook in a downward direction with a monitor camera attached to the tip of the crane. It is used to make the camera face downward and to prevent camera field blur. However, the present invention is not limited to this, and is always smooth regardless of changes in the temperature environment, such as anti-ragging means in hanging devices such as shooting cameras and swinging devices, as well as a cloud base (adjustable tripod) such as an astronomical telescope. Needless to say, the present invention can also be used for various devices that need to be rotated.

It is a front view which shows the attachment state via the bracket of the bidirectional | two-way rotation damper which concerns on this invention, and related apparatus. It is a side view of FIG. FIG. 2 is an enlarged front view of the bidirectional rotary damper shown in FIG. 1. FIG. 4 is a left side view of FIG. 3. FIG. 4 is a right side view of FIG. 3. It is XX sectional drawing in FIG. 4 which shows the 1st best form for implementing this invention. The specific example of a 1st braking member is shown, (a) is a front view, (b) is YY sectional drawing in (a). The specific example of a 2nd braking member is shown, (a) is a front view, (b) is ZZ sectional drawing in (a), (c) is a rear view. It is sectional drawing similar to FIG. 6 which shows the 2nd best form for implementing this invention. It is sectional drawing similar to FIG. 6 which shows the 3rd best form for implementing this invention. It is sectional drawing similar to FIG. 6 which shows the 4th best form for implementing this invention. It is a side view which shows the use condition with respect to the camera for cranes.

Explanation of symbols

P: Case housing the camera Q ... Crane side bracket R ... Camera side bracket 1 ... Casing 2 ... First brake member 3 ... Second brake member 4 ... Shaft member 5 ... End cap (gap adjusting means) 6 ... Adjustment groove ( (Notch groove)
7 ... Stopper screw 8,9 ... Bolt

Claims (4)

A casing,
A shaft member rotatable relative to the casing;
A first braking member disposed on the shaft member in the casing and having at least one of a conical concave surface and a conical convex surface, and fixed to one of the casing and the shaft member;
At least one of a conical convex surface and a conical concave surface that is disposed on the shaft member in the casing and faces and opposes at least one of the conical concave surface and the conical convex surface of the first braking member. A second braking member fixed to the other of the casing and the shaft member,
While molding one or both of the first braking member and the second braking member with resin, forming a plurality of adjustment grooves from the outer peripheral end toward the center,
The first braking member and the second braking member are inclined so that a gap is formed between the opposing surfaces so that the opposing surfaces are in contact with each other at the outer peripheral edge and gradually expand toward the center. Configure with different angles,
The central portion of one of the first braking member and the second braking member is moved relatively in the axial direction relative to the other central portion while the outer peripheral edge portion of the opposing surface is in contact with the central portion. bidirectional rotary damper, characterized in that it comprises adjusting means capable increasing or decreasing the gap the contact area between the opposing surfaces.
The casing has a structure in which both ends are closed by an end wall having at least one end cap as a separate body,
The first braking member is configured to have conical concave surfaces on both sides in the axial direction and fixed to the shaft member, and the second braking member is opposed to the conical concave surfaces on both axial sides of the first braking member. Comprising a pair of members having a conical convex surface, and fixing each of the pair of members to end walls at both ends of the casing,
2. The bidirectional rotary damper according to claim 1, wherein the end cap is configured to be movable with respect to the casing and to be fixed at an arbitrary position in the moving process, thereby forming the gap adjusting means. .   3. The bidirectional rotary damper according to claim 1, wherein a non-flowable lubricant is interposed between the opposing surfaces of the first braking member and the second braking member.   The bidirectional rotation according to any one of claims 1 to 3, wherein at least a portion of the first braking member and / or the second braking member that constitutes at least the facing surface is formed of a synthetic resin material having a low friction coefficient. damper.

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