JP2008215624A - Stand which has energy accumulating section for tare weight balance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve further a balance of a tare weight of a stand on which equipment is arranged freely to be displaced. <P>SOLUTION: In a stand (1;201) having a first stand arm (11) which can swivel freely on a pivot (A3), a second stand arm (13) which is bearing supported by the first stand arm (11) so that it can swivel freely on a rotary shaft (A3') which is parallel to the pivot (A3), a first direction conversion roller (17) which can swivel freely on the pivot (A3) to the first stand arm (11), a second direction conversion roller (19) connected with the second stand arm (13) so as not to be rotated, and a pulling rope (21) of a wheel shape which is tensed around the direction conversion rollers (13) and (19), the pulling rope of the wheel shape (21) is characterized by having rod-like members (83, 85) between the direction conversion rollers (17, 19). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a stand for a device that is movably disposed.

A stand of this kind is known from German Patent 3739080 A1. This well-known stand has an energy accumulating portion that is to be corrected for a rotational moment of an effective load attached to a swing arm of the stand.
In this case, the energy storage unit includes a rope attached to the operating point of the swivel arm, and the rope is diverted toward the tension spring by a diverting roller disposed on the swivel axis. As a result, the energy storage unit applies a force toward the point where the linear rope portion coming from the action point of the peripheral surface of the direction changing roller contacts the peripheral surface of the direction changing roller, to the action point of the swivel arm.

This contact point, called the support point, varies according to the turning position of the turning arm on the circumferential surface of the direction changing roller. This is because the diameter of the direction changing roller is not zero. With this configuration, the stand can only obtain a very rough, not precise weight balance.
The theory of such a stand is It is also described in Hilpert's paper “Gewitssaugleich an femechanischen Geraten” (FEINGERATECHINK, Vol. 14, 2/1965) (see FIG. 7 on page 63). H. The left column on page 63 of the Hilpert article, first paragraph, in the case of a known stand, because of the finite curvature of the turning roller, i.e. the sliding of the support point when the swivel arm swivels or It is clearly shown that only rough weight balancing can be performed by additional rope unwinding and winding. Therefore, the weight G acting on the swivel arm at the load distance l from the swivel axis is:
c ′ · r ′ · L = G · l
It is equalized when the condition is satisfied. In the formula,
c ′ is the spring constant of the weight balance spring,
r ′ is the vertical distance from the pivot axis to the direction changing means,
L is the distance from the pivot axis to the point of application of the weight balancing force.

The above condition provides an accurate weight balance only when assuming that the turning is point-like, i.e., when the turning radius is equal to zero. This fact is It is also specified in the first column on page 63 of the Hilpert article.
German Patent No. 221571 A1 also discloses a stand of this kind. It is constructed according to the principles of Hilpert's paper. However, also in this stand, since the direction changing element for changing the direction of the rope connecting the tension spring to the swivel arm is formed from an inclined surface having a finite curvature, the support point depends on the respective position of the swivel arm. fluctuate.

  Another such stand is known from US Pat. No. 5,320,315 and includes a first stand arm and a second stand arm that is rotatable relative to the first stand arm. . In the case of this well-known stand, a ring-shaped tow rope or endless belt is rotatable relative to the first stand arm, and a second turning arm is coupled to the second stand arm so as not to rotate. It is hung around the direction change roller. With this configuration, the movement of the first stand arm can be combined with the movement of the second stand arm. In this stand, the first direction changing roller is fixed so as not to be twisted with respect to the pedestal portion of the stand. Therefore, when the first stand arm turns, the second stand arm is moved to the pedestal of the stand. Move so that the orientation of the second stand arm relative to the part remains constant.

This type of stand is also known from World Patent No. 88/09151. In this stand, in order to connect the movement of the stand arm with the movement of the weight, a plurality of ring-shaped tow ropes configured as endless toothed belts are sequentially switched. Therefore, this stand is in a balanced state regardless of the position.
However, since the rope, the belt, or the toothed belt has ductility, a slip and a delay occur when the movements of the first stand arm and the second stand arm are connected.

Yet another such stand is known from EP 0 434 426 B1. This stand supports the surgical microscope, and an adjusting device that allows the surgical microscope to be adjusted with respect to the holding arm is arranged between the holding arm of the stand and the surgical microscope. With this configuration, the center of gravity of the surgical microscope can be slid relative to the stand to maintain the balance of the stand / surgical microscope system.
Accordingly, weight balance is established in such a stand. That is, the stand is balanced with respect to its axis of rotation and pivot, and the balance of the stand components that move at each point in time and the weight of the equipment suspended from the stand are moving as the equipment moves. Only the inertia of the device needs to be overcome, and it is kept from being necessary to suppress gravity.

  In the case of this stand known from EP 0433426 B1, the adjusting device comprises two linear carriages which are slidable in mutually orthogonal directions. The linear carriage is disposed on a frame that limits the adjustment range. Therefore, this adjusting device is relatively large and heavy. Since the equipment always moves with the adjustment device, the bulky adjustment device limits the ability of the device to move, and the large mass of the adjustment device increases the inertia of the movement of the device and makes it difficult to maintain the balance of the stand. There is a risk that.

  The object of the invention is to further improve the weight balance of the stand of the kind mentioned at the outset.

The present invention includes a first stand portion, a swivel arm that is attached to the first stand portion and is pivotable with respect to the pivot axis, and is second movable with respect to the first stand portion. And an energy storage unit that applies a force toward the support point of the first stand part to the fixed action point of the swivel arm. The points constitute a vertical plane, and when the stand arm turns, the bearing point is spatially fixed with respect to the first stand part.
If the pivot axis and the support point define a vertical plane at the fixed action point of the swivel arm and the support point is spatially fixed to the first stand portion when the swivel arm is swiveled, the stand according to the prior art The attendant error due to the finite diameter of the diverting roller is eliminated, resulting in a substantially precise weight balance.

The energy storage part advantageously comprises a compression spring configured as a tension spring. Thereby, even if the energy storage unit is destroyed, it is impossible to control the downward movement of the swing arm.
In another advantageous embodiment, the energy storage part acts on the swivel arm via a rope attached to the point of action, and the rope roller that redirects the rope to the point of action is located on the outer circumferential surface of the rope roller. It is supported so that it can pivot with respect to the support point. This makes it possible to combine the advantages of the rope in terms of weight and the configuration of turning the rope with a roller with little friction with the advantages of a substantially spatially fixed bearing point and an exact weight balance.
If the energy storage unit is housed in the first stand portion, the energy storage unit can be mounted without particularly reducing the space and without sacrificing the operability or adjustment capability of the stand.

In another embodiment, the energy storage portion includes a compression spring supported between a ring-shaped stopper fixed to the first stand portion and a slidable piston connected to the rope. With this configuration, most of the appropriate compression spring can be utilized for the energy storage.
If the action point is placed on a sliding member that is slidable along the longitudinal groove of the swivel arm perpendicular to the swivel axis, the slide member can be easily slid even if the weight of the device to be supported by the stand changes. Only then can the weight balance be regained.

For that purpose, it is particularly advantageous to engage the sliding member in a spiral groove which is rotatable about a rotation axis perpendicular to the pivot axis. By rotating the spiral groove, the sliding member slides along the longitudinal groove, and the action point changes accordingly.
If the spiral groove is configured as an Archimedean spiral, the sliding of the action point is always proportional to the rotation angle at which the spiral groove rotates.

In yet another very rugged embodiment, the energy store acts on the point of action via a tension bar.
A bearing fixed to the first stand portion includes a cylinder / piston structure mounted on the first stand portion such that the energy storage portion is rotatable with respect to the rotation axis including the support point. The position of the point can be realized accurately and sufficiently without play.
There are many compression springs available, but in a cylinder / piston configuration, the compression spring is supported between the piston that couples to the tension bar and the inner surface of the hollow cylinder.
If the cylinder / piston structure is arranged on the side of the swivel arm and the end of the tension bar opposite to the piston side is attached to the operating point via the horizontal bar, the swivel range of the swivel arm is controlled by the energy storage unit. No longer limited.

  According to another aspect of the invention, the problem underlying the invention is also solved by the features of claim 13. That is, the first stand arm that can pivot with respect to the pivot axis, and the second stand that is supported by the first stand arm so as to be pivotable with respect to another rotation axis that is parallel to the pivot axis. Stand arm, a first direction changing roller that is rotatable with respect to a rotation axis with respect to the first stand arm, and a second direction changing roller that is coupled so as not to rotate with the second stand arm The ring-shaped tow rope has a rod-shaped portion between the direction change rollers.

According to the features of claim 13, the movements of the first stand arm and the second stand arm of a stand of the kind mentioned at the beginning are more accurately and directly coupled in a reactive manner, Weight balancing based on such movement coupling is improved. In this case, according to the present invention, only the portion of the ring-shaped tow rope that is in direct contact with the direction changing roller may be formed as a flexible rope. The effect of rope stretching is almost eliminated.
According to the features of claim 13, it is possible to alleviate the very strong tension of the ring-shaped tow rope that would otherwise be necessary to alleviate the problem of the rope stretch, and as a result, The risk is reduced and the burden on the bearing part of the direction changing roller is reduced.

  If the two direction changing rollers have the same diameter, the movement of the first stand arm relative to the pedestal portion of the stand is converted into the movement of the second stand arm with the same magnitude. Thereby, even when the first stand arm pivots with respect to the first turning roller fixed with respect to the pedestal portion of the stand, the second turning roller with respect to the pedestal portion of the stand, and therefore The alignment state of the second stand arm can be kept unchanged.

In an advantageous embodiment, the length of the flexible rope part located between the rigid rod-like parts limits the pivoting range of the stand arm. With this configuration, the flexible rope portion that provides the residual rope stretching effect is as short as possible.
When the rod-like portion is coupled to the flexible rope portion via the coaxial screw coupling portion, the stress of the flexible rope portion can be adjusted particularly easily. In this case, if the rod-shaped part has such screw joints at both ends and the rotation directions of the two screw joints are reversed, the appropriate rod-shaped part can be simply rotated and the ring-shaped towing is performed. A rope can be stretched.

According to a further aspect of the invention, the problem underlying the invention is also solved by the features of claim 19. That is, it has a holding arm and an adjusting device attached to the holding arm, and the device can be arranged on the adjusting device, and the device can be adjusted with respect to the holding arm. The adjusting device is a linear carriage / swivel device.
Thus, by configuring the adjusting device as a linear carriage / swivel device, the adjusting device can be configured more compactly, for example, without a frame that limits the adjustment range, and accordingly, the entire stand is configured to be lighter. This makes it easier to balance the stand and hence the weight.
The linear carriage / swivel device is disposed on the linear part, linear carriage that is slidable by a threaded spindle along the base part, and is pivotable with respect to the pivot axis with respect to the linear carriage; It is advantageous to have a pivoting element that can fix the device.

In an advantageous embodiment, the axis of rotation of the threaded spindle is perpendicular to the pivot axis of the pivot element. With this configuration, the linear carriage / swivel adjustment mechanism is particularly easy to understand for the stand user.
If the linear carriage / swivel device is arranged on the holding arm so as to be rotatable with respect to the rotation axis of the stand and the rotation axis is parallel to the rotation axis, the center of gravity of the device is adjusted by the linear carriage / swivel device. It can be moved to the rotating shaft properly, particularly rapidly.

  In another advantageous embodiment, the swivel element is pivotable via a worm gear device, and the user can operate the worm gear device manually via a rotary knob. With this configuration, when the stand is used, the direction in which the turning element should be turned for the purpose of maintaining the weight balance can be directly detected by the rotary knob and the rotation moment generated in the device fixed to the turning element.

According to a further aspect of the present invention, the problem underlying the present invention is also solved by the features of claim 25. That is, a first stand portion and a second stand that is attached to the first stand portion and has a turning arm that is turnable with respect to the turning shaft, and is movable with respect to the first stand portion. A second stand portion of the swivel arm, which has a rotational moment corresponding to the weight load G disposed at a load distance l from the swivel axis, and the swivel axis from the swivel axis. In order to apply a weight balancing force to the action point arranged at a position with a distance L, a weight balancing spring having a spring constant c and a position at a vertical distance r from the swivel axis are arranged, and the turning radius is In a stand of a device to be movably arranged having an energy storage for balancing the weight load G, having a directional turning means that is finite, it is limited within a wide swivel range of the swivel arm To minimize the weight balancing errors generated by counter conversion radius, the spring constant c and / or vertical distance r is smaller than the weight balancing target value on each theory, as a result,
c · r <(G · l) / L
It is characterized by being.

In accordance with the present invention, by reducing the spring constant and / or the vertical distance compared to their respective theoretical uncorrected values, the weight balance error caused by the finite turning radius is minimized over a wide swivel range. Can be. According to Applicants' experiments, if the values of the spring constant c and the vertical distance r are set appropriately, the weight balance error can be kept below 1% in the 40 ° turning range, while the uncorrected vertical distance r The error in 'and uncorrected spring constant c' is from minus 4% (rotational moment for the swivel arm is under-compensated) to plus 7% (rotational moment for the swivel arm is over-compensated) in a predetermined 40 ° swivel range. I know that.
If the weight balance spring is a compression spring formed as a tension spring, even if the weight balance spring breaks, control of the downward movement of the swivel arm cannot be prevented.

In one embodiment, the diverting means includes a rope roller, and the tow rope wrapped around the rope roller transmits a weight balancing force from the weight balancing spring to the pivot arm. In this embodiment, a means for correcting an error in weight balance is combined with a direction changing means with particularly low friction.
If the tow rope includes a vertical tow rope portion between the weight balance spring and the rope roller so that the vertical tangent of the rope roller defined by the vertical tow rope portion intersects the pivot axis, the direction changing roller is With respect to the pivot axis and the direction of the weight balancing force, it will be arranged in such a way as to make error correction particularly effective by reducing the spring constant and / or the vertical distance.
In this case, if the direction changing means includes another rope roller arranged at an equal vertical distance r from the turning axis, the turning arm can be turned in two directions beyond the vertical position.

According to the applicant's experiment, a particularly convenient error correction can be performed by making the difference between the vertical distance r and the uncorrected value r ′ proportional to the radius of the rope roller.
The difference between the vertical distance r and the uncorrected value r ′ is 0.35 to 0.45 times, preferably 0.4 times the radius of the rope roller, and the spring constant c is 0 of the uncorrected spring constant c ′. It has been found to be particularly advantageous to be .75 to 0.85 times, preferably 0.8 times.
The stand described below is an embodiment of the present invention that is generally advantageous with respect to weight balancing. The cooperation of the energy storage structure with other components of the stand, in particular the counterweight, the parallelogram of the joint, the parallelogram linear carriage / swivel of the rope, etc. is a particularly advantageous aspect of the present invention.

Hereinafter, the present invention will be described based on embodiments and the accompanying drawings.
FIG. 1 is a side view schematically showing an embodiment of a stand according to the present invention. The stand denoted by reference numeral 1 in the figure supports a surgical microscope 3 that should be able to move freely as an instrument.
The stand 1 includes a pedestal portion 7 that is rotatably supported with respect to a vertical rotation axis A <b> 1 on a bottom portion 5 that is slidable by a roller 4. The swivel arm 9 mounted on the pedestal portion 7 can swivel about a swivel axis A2 that is perpendicular to the plane of the drawing of FIG.
A support arm 11 is attached to the upper end of the swivel arm 9, and the support arm 11 can swivel with respect to the swivel arm 9 with respect to a rotation axis A3 that is parallel to the swivel axis A2. The coupling member 22 is mounted on a rotation axis A3 ′ parallel to the rotation axis A3 so that the alignment state of the coupling member 22 is always maintained as described later. Further, the uniaxial rotary joint 24 disposed between the coupling member 22 and the equipment arm 13 rotates the equipment arm 13 with respect to the rotational axis A6.

A holding arm 15 is attached to the device side end of the device arm 13 so as to be rotatable with respect to the rotation axis A5. This rotation axis A5 is located in the plane of the drawing of FIG. 1 and should not substantially intersect with the rotation axis A6 which is always vertical. For reasons of space, the equipment arm 13 is bent, and a rotary joint 14 that can rotate the holding arm 15 with respect to the rotation axis A5 is provided at the end on the holding arm side.
The surgical microscope 3 is attached to the end of the holding arm 15 on the apparatus side via the adjusting device 16 so as to be rotatable with respect to the rotation axis A4. When the stand 1 is in the position shown in FIG. 1, the rotation axis A4 is perpendicular to the plane of the drawing of FIG. 1, and the holding arm 15 is configured such that the rotation axis A4 and the rotation axis A5 are orthogonal to each other.

The fact that the operating microscope 3 moves freely means that when the operating microscope 3 moves, the moment of inertia and / or the friction of the bearing must be overcome, but it is not necessary to suppress the gravity or weight rotation moment. This means that the stand 1 must be in a neutral balanced state with respect to the respective rotation axis or pivot axis. This condition is satisfied when the center of mass of the mass to be swiveled is located on the swivel axis, i.e. when the stand is balanced with respect to this swivel axis.
When the center of mass is not on the pivot axis, an alternative configuration is to supply the gravitational energy to be released or generated by changing the height position of the moving mass in the earth's gravitational field when pivoting about the pivot axis As a result, it is possible to provide an energy storage unit that maintains the balance of the rotational moment of the center of gravity with respect to the turning axis.
As will be described below, the stand 1 utilizes two possibilities. That is, one energy storage unit corresponds to each of the turning axis A2 and the rotation axis A5, and the balance of the stand 1 should be maintained with respect to the rotation axes A3 and A4. Since the rotation axes A1 and A6 are always oriented vertically, the gravitational energy is neither released nor consumed during rotation, so that the center of gravity of the kinetic mass for each rotation is taken as their rotation axis. It is not necessary to put it on itself.

First, the weight balance of the stand 1 regarding the rotation axis A3 will be described.
A parallelogram arm 35 parallel to the swivel arm 9 is attached to the end of the support arm 11 on the side opposite to the device by a uniaxial rotary joint 33. Further, the connecting rod 37 is attached to the end of the swivel arm 9 on the side opposite to the support arm side via the uniaxial rotary joint 39 and the support arm of the parallelogram arm 35 via the uniaxial rotary joint 41. It is mounted on the end opposite to the side. In this case, the rotating shafts of the joints 33, 39 and 41 are parallel to the rotating shaft A3, and the distance between the rotating shaft A3 and the rotating shaft of the joint 33 is equal to the separation distance of the rotating shafts of the joints 39 and 41. The distance between the axis A3 and the rotation axis of the joint 39 is equal to the distance between the rotation axes of the joints 39 and 41. Therefore, the swivel arm 9, the parallelogram arm 35, the support arm 11, and the connecting rod 37 form a parallelogram of joints.

In order to balance the stand 1 with respect to the rotation axis A3, a counterweight 43 or 44 is slidably disposed on the connecting rod 37 and the parallelogram arm 35, respectively.
Furthermore, the size of the slidable counterweight 43 or 44 is defined so that the parallelogram joint is stable and open as shown in FIG. Only placement is essential. Thereby, the stand 1 is in a desired neutral state with respect to the rotation axis A3.
For example, when the weight of the surgical microscope 3 changes due to the use of an accessory for the surgical microscope, the balance with respect to the rotation axis A3 can be reproduced by appropriate sliding of the counterweights 43 and 44.

Next, the weight balance of the stand 1 related to the turning axis A2 will be described.
Due to the counterweights 43 and 44 and the parallelogram joints, the mass of the surgical microscope 3, the holding arm 15, the instrument arm 13 and the support arm 11 is related to the pivot arm 9 or pivot with respect to the pivot axis A2 and pivot arm 9. It acts as if a smaller “effective mass” is on the extension line of the arm 9.
In order to balance the residual rotational moment applied to the swivel arm 9 with respect to the swivel axis A2 by the reduced “effective mass”, that is, for the weight balance with respect to the swivel axis A2, an energy storage 45 is provided. The energy storage unit 45 is attached to the swing arm 9 at a position 47 and to the pedestal portion 7 of the stand 1 at a position 49. The energy to be released or generated by changing the height position of the “effective mass” in the gravity field of the earth when the swivel arm 9 swivels about the swivel axis A2 is stored or supplied by the energy storage unit 45. Is done.

  That is, since the energy storage unit 45 is provided, the counterweights 43 and 44 only need to establish a desired neutral balance state with respect to the rotation axis A3, and the counterweights 43 and 44 are relatively separated from the rotation axis A3. By doing so, an advantageous lever ratio can be obtained, so that the masses of the counterweights 43 and 44 can be kept relatively small. Therefore, the inertial force to be overcome when the surgical microscope 3 is moved can be relatively reduced by the energy storage unit 45.

The principle functional method of such an energy storage unit is described in H. publishing in the magazine FEINGERATECHNIK Vol. 14, No. 2/1965. This is described in Hilpert's paper “Gewitssaugleich an feinmechanischen Geraten”. In the context of the stand according to the invention, the structure of the energy storage part shown in FIGS. 6 and 7 of this paper is particularly important.
The energy storage unit 45 applies a force acting on the swivel arm 9 at a position 47 in a direction toward the support point 49, and this force is opposite to the rotational moment applied to the swivel arm 9 with respect to the swivel axis A <b> 2 by “effective mass”. In this way, the swivel arm 9 is held with the entire stand in a neutral state with respect to the swivel axis A2.
With such a neutral state, the surgical microscope 3 can be positioned without applying force at any position in the working space obtained from being movable with respect to the pivot axis A2. In this case, each point of the sliding path that can be taken by the surgical microscope 3 is a balance point at which the combined force acting on the surgical microscope 3 disappears. Therefore, when the surgical microscope 3 is supported, the inertial force generated by the mass to be moved must be overcome.

As is clear from the above-cited paper “Gewitssaugleich an femechanischen Geraten”, in order to maintain the balance with respect to the pivot axis A2, in order to maintain the balance with respect to the pivot axis A2, the pivot axis A2 and the support point 49 are perpendicular to each other. It is necessary to arrange them vertically in the direction. That is, the vertical plane 50 must be defined by the pivot axis A2 and the support point 49.
However, the energy storage structure disclosed in the above-mentioned journal article satisfies this vertical plane condition for only one pivot position of the corresponding pivot arm, and in other pivot ranges, the support point is the vertical plane. As a result, a residual rotational moment determined by the swivel angle is applied to the swivel arm. Unlike this known stand, the bearing point 49 of the stand according to the invention remains fixed with respect to the pedestal part 7 when the swivel arm 9 swivels, and therefore always has a vertical plane 50 with the swivel axis A2. Form. Therefore, the stand according to the present invention is in an exact balanced state at any position of the swivel arm 9.

2 is a detailed partial cross-sectional view of the energy storage unit 45 of the stand 1 when the swivel arm 9 is in a vertical position, as viewed in the direction of arrow II in FIG.
The energy storage unit 45 includes a cylindrical housing 53 that is rotatably arranged with respect to a rotation shaft 57 that is parallel to the turning axis A2. The two shaft pins 55 are fixedly engaged with a holding side wall portion 59 that is coupled to the pedestal portion 7 of the stand. The tension bar 61 protrudes into the cylindrical housing 53, and one end of the compression spring 65 is in contact with the end 63 of the tension bar 61 formed in a piston shape. The other end of the compression spring 65 is in contact with the front surface 67 of the cylindrical housing 53 opposite to the piston.
The pull bar 61 is connected to the horizontal bar 69 outside the cylindrical housing 53. The horizontal bar 69 is attached to the tension bar 61 via a rotary bearing 71 and is attached to the swivel arm 9 via a rotary bearing 73, that is, a connecting portion 47 shown very schematically in FIG. Yes. Therefore, the support point 49 is at the intersection of the rotation shaft 57 of the housing 53 of the energy storage unit and the parallelogram plane of the joint including the pivot shaft 9 and the parallelogram arm 35.
FIG. 2 also shows a slewing bearing 77, and the slewing arm 9 is supported on the shaft pin 79 of the pedestal portion 7 of the stand via the slewing bearing 77 so as to be pivotable with respect to the pivot axis A 2. Yes.

A functional method of the energy storage unit 45 will be described with reference to FIG. FIG. 3 is a side view of the detailed view of FIG. 2 as viewed in the direction of arrow III in FIG. 2, and the energy storage unit 45 is shown in a sectional view in FIG. However, the situation shown in FIG. 3 differs from FIG. 2 in that the swivel arm 39 in FIG. 2 is oriented vertically, whereas in FIG. 3, the swivel arm 39 is swung from a vertical position to an oblique position. Yes.
When the swivel arm 9 is in the position shown in FIG. 2, the center of gravity of the “effective mass” that applies the load to the swivel arm 9 is located strictly above the swivel axis A2, so Does not work at all. Therefore, the compression spring 65 in the stand position shown in FIG. 2 occupies the entire space inside the housing 53 of the energy storage unit.

When the swivel arm 9 is in the position shown in FIG. 3, the “effective mass” generates a rotational moment that tries to swivel the swivel arm 9 counterclockwise with respect to the swivel axis A2. However, since the compression spring 65 is compressed at this position shown in FIG. 3, the tension bar 61 protrudes out of the housing 53 of the energy storage unit more than the position of FIG. The spring force generated by the compression of the compression spring 65 opposes the “effective mass” rotational moment and holds the swivel arm 9 in a balanced state.
Since the longitudinal axis 61a of the tension bar 61 indicated by the chain line in FIG. 3 intersects with the rotation axis 57 and the direction of the spring force applied to the pivot arm 9 is parallel to the longitudinal axis 61a of the tension bar, the spring force is 9 in the region of the connecting portion 47 of the energy storage section 49 and directed to a bearing point 49 located on the rotation shaft 57 of the housing 53 of the energy storage section. In this case, due to the transmission of force via the horizontal bar 69 shown in FIG. 2, the line connecting the force application point in the region of the connecting portion 47 and the support point 49 is parallel to the tension bar 61.

The support point 49 is located on the rotation shaft 57 of the housing 53 of the energy storage unit, and the rotation shaft 57 remains spatially fixed even if the swivel arm 9 swivels relative to the rotation axis A2. And it shows with a chain line in FIG. The plane 50 including the bearing point 49 and the pivot axis A2 is always vertical.
H. According to the above article by Hilpert, the spring constant of the compression spring 65 can be adapted to a specific stand configuration, in particular to the force action point 47 of the swivel arm 9 that is specifically set, depending on the application situation. In this regard, see equations (15) and (22) on pages 62 and 63 of the above paper.

An additional energy storage unit 95 schematically shown in FIG. 4 is provided in the equipment arm 13 for weight balancing with respect to the rotation axis A5. Hereinafter, simply referring to FIG. 4 means FIG. 4A. This energy storage unit 95 is also H.264. It operates according to the principles specified in the Hilpert paper, and likewise removes the disadvantages of the energy storage described in this paper.
As shown in FIG. 4, the second energy storage unit 95 includes an adjustment element, and the structure and functional system of the energy storage unit will be described with reference to FIGS. 5, 6, and 7. .
FIG. 5 is a cross-sectional view showing a part of the energy storage unit 95 disposed in the equipment arm 13 as seen in the direction of the arrow V in FIG. Therefore, the rotation axis A5 is perpendicular to the plane of the drawing of FIG.
FIG. 6 is a cross-sectional view corresponding to FIG. 5 and shows the energy storage unit 95 when the holding arm 15 is at another rotational position with respect to the rotational axis A5.
The lever arm 99 arranged in parallel with the rotation axis A4 is fixedly coupled to the holding arm 15 and thus can pivot with respect to the rotation axis A5 together with the holding arm 15. The lever arm 99 is orthogonal to the rotation axis A5.

As will be described below, since the center of gravity of the surgical microscope 3 is located on the rotation axis A4 and the rotation axes A4 and A5 are orthogonal to each other, the rotational moment applied to the holding arm 15 by the surgical microscope 3 is It acts as if the microscope 3 is placed on the lever arm 99 or on its extension. In this case, the distance from the intersection of the rotation axes A4 and A5 to the surgical microscope 3 is H.264. Should be equal to the lever length l according to the above article by Hilpert.
Therefore, the balance of the stand 1 can be maintained by the energy storage unit 95 acting on the lever arm 99 with respect to the rotational moment applied by the surgical microscope 3 with respect to the rotational axis A5.
Further, a rope 103 is stretched between the lever arm 99 and the piston 101 slidably housed inside the cylindrical device arm 13, and the rope 103 is stretched in the longitudinal direction of the device arm 13 by a rope roller 105. The direction is changed from the shaft to the operating point 107 of the lever arm 99. A helical compression spring 111 is supported between a piston 101 inside the device arm 13 and a ring-shaped stopper 109 on the holding arm side.

Since the piston 101 is pulled toward the rotation axis A5 via the rope by the rotation of the lever arm 99 with respect to the rotation axis A5 linked to the rotation of the holding arm 15, when the holding arm 15 rotates with respect to the rotation axis A5, the compression is performed. The spring 111 is compressed to the position shown in FIG. As a result, the spring force applied to the lever 99 and thus to the holding arm 15 acts on the acting point 107 and is directed to the bearing point 113 on the peripheral surface of the rope roller 105. This spring force corrects the rotational moment applied to the rotation axis A5 by the mass of the holding arm 15, the adjusting device 16, and the surgical microscope 3, and establishes a neutral balanced state with respect to the rotation about the rotation axis A5.
The rope roller 105 is supported in a seesaw shape so that it can freely rotate with respect to the support point 113. A change in the position of the center point 115 of the rope roller 105 that occurs with the turning of the holding arm 15 is indicated by a bidirectional arrow 117. With this configuration, even if the holding arm 15 or the lever arm 99 pivots with respect to the rotation axis A5, the support point 113 remains spatially fixed.

The plane of the drawing of FIG. 4 is a vertical plane and includes both the axis of rotation A5 and the longitudinal axis of the instrument arm 13, and the bearing point 113 is on this longitudinal axis of the instrument arm 13, so Defines a vertical plane together with the pivot axis A5 of the holding arm 15. In FIG. 4, the longitudinal axis of the holding arm 13 is determined by a line connecting the tips of two arrows V.
Since the rope roller 105 is supported in a seesaw shape at the support point 113 as described above, when the holding arm 15 rotates, the center point 115 of the rope roller 105 remains fixed and the support point is fixed. It is certain that the plane defined by 113 and the pivot axis A5 always moves so as to be a vertical plane.
Accordingly, the center of mass of the holding arm 15, the adjusting device 16, and the surgical microscope 3 is positioned on the rotation axis A <b> 4 parallel to the lever arm 99 as described above in relation to the energy storage unit 45. If so, the holding arm 15 is in a neutral state in any swiveling position.

Even when an accessory is attached to the surgical microscope 3, the action point 107 of the rope 103 is slidable along the lever arm 99 in order to obtain a balance about the rotation axis A <b> 5. As a result, H.C. In principle, the energy storage structure shown in FIG. 7 is realized in the Hilpert paper.
For this purpose, the point of action 107 is arranged on a sliding member 121 which is slidably guided along a longitudinal groove 119 of the lever arm 99 orthogonal to the rotation axis A5. The sliding member 121 is engaged with the spiral groove 125 of the Archimedes spiral 127 that is rotatable with respect to the rotation axis A5 together with the lever arm 99 by the pin 123. The Archimedean spiral 127 is located on a plane parallel to the lever arm 99 and the rotation axis A5. A rotary knob 97 fixedly coupled to the Archimedes spiral 127 allows the Archimedes spiral 127 to be rotated relative to the lever arm 99 with respect to a rotational axis 98 orthogonal to the rotational axis A5, thereby along the lever arm 99. The distance between the spring force acting point 107 to be guided and the turning axis A5 can be adjusted. Since the guide groove 125 with which the pin 123 engages is an Archimedean spiral, the change in the distance is always proportional to the rotation angle of the rotary knob 97.

  Instead of the Archimedes spiral 127 or 125, it is also possible to adjust the sliding member 121 using a threaded spindle that should be arranged parallel to the lever arm 97 and can be adjusted from the rotary knob 97 via a bevel gear. Is possible. The rotary knob 97 should be arranged as shown in FIG. 5 with respect to the lever arm 99 so as not to limit the swivel range of the holding arm 15 by the rotary knob 97 hitting the end of the slit 129 of the equipment arm 13. Let's go.

FIG. 7 shows the seesaw-like support state of the rope roller 105 in more detail. FIG. 7 is a cross-sectional view seen in the direction of arrow VII in FIG.
The rope roller 105 is supported by the support portion 131 so as to be rotatable with respect to the rotation shaft 137 passing through the center point 115 thereof. The support portion 131 is supported by a ring-shaped stopper 109 of the equipment arm 13 so as to be rotatable with respect to a rotation shaft 135 that intersects the support point 113 by a rotary bearing 133. As a result, the rope roller 105 is supported in a seesaw shape at a support point 113 so as to be rotatable with respect to the rotation shaft 135, and the support point 113 is located on the rotation shaft 135 at the center of the finite cross section of the rope 103. Has been placed.

  Further, regarding the energy storage unit 95, H. Based on Hilpert's paper, the appropriate spring constant of the compression spring 111 and the position of the force application point 107 in the lever arm 99 can be easily determined according to a predetermined application. In this regard, see especially equations (15) and (22) on pages 62 and 63 of this paper. In the energy storage unit 95, if the average value of the spring constant is appropriately set, the weight balance in each case can be established by performing a test, that is, by appropriately sliding the force acting point 107. Is possible.

Hereinafter, returning to FIG. 1, the rotation axis A6 is always oriented in the vertical direction. As a result, the center of gravity of the mass swung with respect to the rotation axis A6 is made to correspond to the rotation axis A6. The reason why the adjustment / movement toward the rotation axis A6 can be stopped will be described.
At the upper end of the swivel arm 9, a direction changing roller 17 is supported which is coupled to the horizontal arm 23 which is always oriented in the horizontal direction around the rotation axis A3. At the end of the support arm 11 on the equipment arm side, another direction changing roller 19 that is rotatable with respect to the support arm 11 is supported around a rotation axis A3 ′ parallel to the rotation axis A3. A ring-shaped tow rope 21 is looped around the direction changing rollers 17 and 19 without slipping. In this case, the coupling member 22 is disposed on the direction changing roller 19 so as not to rotate.

The horizontal arm 23 disposed so as not to be twisted by the direction changing roller 17 is coupled to one end portion of the parallelogram bar 27 via the uniaxial rotary joint 25, and the other end of the parallelogram bar 27. Is attached to the pedestal portion 7 of the stand 1 through a uniaxial rotary joint 29. The rotation axes of the joints 25 and 29 are parallel to the rotation axis A2 or A3.
The portion of the swivel arm 9 located between the rotation axes A2 and A3 includes the parallelogram bar 27, the horizontal arm 23, and the imaginary, therefore, the line 31 shown in FIG. Together with the joint parallelogram. Therefore, the distance between the turning axis A2 and the rotation axis A3 is equal to the distance between the rotation axis of the rotary joint 25 and the rotation axis of the rotary joint 29. Furthermore, the distance between the turning axis A and the rotation axis of the joint 29 is equal to the distance between the rotation axis A3 and the rotation axis of the joint 25. Further, since the horizontal position of the connecting line 31 shown by the chain line does not change while the stand 1 is swiveling with respect to the axes A1 to A6, the horizontal arm 23 is always independent of the position of the swivel arm 9 each time. Oriented horizontally.

When the support arm 11 rotates with respect to the rotation axis A3 or when the rotation arm 9 rotates with respect to the rotation axis A2, the direction changing rollers 17 and 19 always change the direction changing roller 17 with respect to the vertical direction with respect to the support arm 11. And 19 so that the orientation remains constant. This is because the horizontal arm 23 is fixedly connected to the direction changing roller 17, and the direction changing roller 17 is connected to the direction changing roller 19 through a ring-shaped tow rope 21 that forms a parallelogram of the rope. .
Since the device arm 13 is fixedly coupled to the direction changing roller 19 via the coupling member 22, the direction of the roller with respect to the vertical direction is always constant. Therefore, when the turning arm 9 or the support arm 11 is turned, the rotation axis A6 itself always remains in the vertical direction.

FIG. 4 shows an area of the stand 1 including the front portion of the support arm 11, the instrument arm 13, the holding arm 15, and the surgical microscope 3.
As is evident from FIG. 4, the tow rope 21 is formed as a flexible rope 81 in the area of the turning rollers 17 and 19 and as a rigid rod part 83 or 85 between the rollers 17 and 19. Is formed. The rope portion 81 is slipped around the direction change rollers 17 and 19, and the length thereof is the contact between the rigid rod portions 83 and 85 and the direction change rollers 17 or 19 over the entire swivel region of the support arm 11. It is stipulated not to occur.

  By constructing the parallelogram of the rope including the direction changing rollers 17 and 19 and the ring-shaped tow rope 21 in this way, the weight advantage of the parallelogram of the rope with respect to the parallelogram of the bar is maintained. However, it is possible to minimize the influence of the hysteretic rope stretching caused by the rope. Thus, the advantage of the light weight of the tow rope can be combined with the high rigidity of the bar. In order to suppress the influence of this hysteresis-like stretching, strong rope tension is required at the parallelogram bar portions 83 and 85 of the rope, and as a result, an excessive load is applied to the bearings of the direction changing rollers 17 and 19. This will not happen.

As is evident from the enlarged detail of FIG. 4, particularly FIG. 4B, the rigid rod portion 85 has internal threads 84 and 86 at both ends thereof. In this case, the female screw 84 is a clockwise screw and the female screw 86 is a counterclockwise screw. Corresponding set screws 80 and 82 that are fixedly coupled to the flexible rope portion 81 are screwed onto the female screws 84 and 86. The tension of the ring-shaped tow rope can also be changed by rotating the rod portion 85.
FIG. 4C shows another method for joining a rigid rod portion with a flexible rope portion.

In this embodiment, the rod portion 185 has a male thread that is screwed into the threaded hole 189 of the distal end 180 configured as a case. The coupling member 180 has an annular step 191 at the end opposite to the rod portion, and a disk 187 fixedly coupled to the rope 81 abuts on the annular step 191.
In this embodiment, the other end of the rod portion 185 can be coupled to the rope portion 81 via the same coupling member or via a clamping element.

Hereinafter, the weight balance of the stand 1 with respect to the rotation axis A4 will be described.
Furthermore, the adjusting device 16 inserted between the holding arm 5 and the surgical microscope 3 moves the center of gravity of the surgical microscope 3 onto the rotation axis A4, and accordingly, the stand 1 is balanced with respect to the rotation axis A4. Can do.
FIG. 8 is a side view of the adjusting device 16 as seen in the direction of the arrow VIII in FIG.
The adjusting device 16 is configured as a linear carriage / swivel device including a linear carriage 139 and a pivot element 141. The linear carriage 139 is slidable in the direction of the double arrow 143 along the base portion 145. The base member 145 is rotatable with respect to the rotation axis A4 of the linear carriage / swivel device 16. The linear carriage 139 is provided with a turning element 141 so as to be slidable in the direction of a double arrow 143 together with the linear carriage and to be rotatable with respect to the turning shaft 147. The surgical microscope 3 is fixed to the swivel element 141. Since the base member 145 is mounted on the holding arm 15 so as to be rotatable with respect to the rotation axis A4, the surgical microscope 3 can be rotated together with the linear carriage / swivel device 16 with respect to the rotation axis A4.
FIG. 8 further shows a rotary knob 149 for sliding the linear carriage 143 and another rotary knob 151 for turning the turning element 141 with respect to the turning shaft 147. Therefore, the rotary knob 151 acts on a worm gear 153 having an inclined tooth portion formed on the turning element 141.

FIG. 9 is a cross-sectional view of the linear carriage / swivel device 16 including the rotation axes A4 and A7 along the cutting line indicated by the arrow IX in FIG.
As is apparent from FIG. 9, the rotary knob 149 allows the threaded spindle 155 to rotate with respect to the rotation shaft 156 located in the plane of the drawing of FIG. The threaded spindle 155 passes through the threaded hole 158 of the linear carriage 139 that is slidably guided in the direction of the double arrow 143 in FIG. Therefore, by rotating the rotary knob 149, the linear carriage 139 can be moved up and down with respect to FIG.

In the linear carriage 139, another threaded spindle 159 is disposed so as to be rotatable with respect to a rotation shaft 161 orthogonal to the plane of the drawing of FIG. This second threaded spindle 159 meshes with the inclined teeth of the worm gear 153 of the pivoting element 141. Since the worm gear 153 is rotatable with respect to the rotation shaft 147 with respect to the linear carriage 139 via the rotary bearing 163, the rotation of the rotating element 141 and the operation microscope 3 with the rotation of the threaded spindle 159 is performed. Can be made. Such rotation of the threaded spindle 159 is obtained by a rotary knob 151 shown in FIG.
Also apparent from FIG. 9 is a rotating bearing 165 that allows rotation of the linear carriage / swivel device 16 with respect to the axis of rotation A4.

FIG. 10 is a plan view of the linear carriage / swivel device 16 in the direction of arrow X in FIG. 9 with the swivel element 141 swung from a vertical position.
From FIG. 10, the portion 167 of the linear carriage 139 that receives the threaded spindle 159 can be clearly seen, and the fixing hole 169 formed in the pivoting element 141 is used to illustrate in FIG. For this reason, a surgical microscope not displayed is fixed to the turning element 141. The rotation axis A4 is perpendicular to the plane of the drawing of FIG. It should be noted that although only the pivoting element 141 can pivot with respect to the rotating shaft 147, the entire linear carriage / swivel device 16 shown in FIG. 10 can pivot with respect to the rotating shaft A4. .

  FIG. 11 is a side view schematically showing another stand 201 according to the present invention. Each element of the stand 201 corresponding to the element of the stand 1 of FIGS. 1 to 10 is indicated by the same reference numerals in FIGS. 1 to 10. For the description of the stand 201, see the description of FIGS.

Hereinafter, the weight balance of the stand 201 with respect to the turning axis A2 will be described.
In order to balance the residual rotational moment applied to the swivel arm 9 with respect to the swivel axis A2 by the reduced “effective mass”, that is, to maintain the weight balance with respect to the swivel axis A2, the energy accumulation that acts in the same manner as the energy accumulation unit 45. A portion 245 is provided.
The energy storage unit 245 includes a weight balance spring 246 that applies a weight balance force to the action point 47 of the swing arm 9 by the tow rope 248. The tow rope 248 is changed in direction from the vertical plane 50 including the pivot axis A2 to the action point 47 via the direction changing means 249.

FIG. 12 shows the energy storage unit 245 in detail.
The direction changing means 249 for changing the direction of the tow rope 248 connected to the weight balance spring 246 to the operating point 47 includes a first rope roller 251 and a second rope roller 253, which rope rollers are provided on the base portion 7. The portion 255 is disposed so as to be rotatable with respect to a rotation axis parallel to the turning axis A2.
A weight balance spring 246 is disposed in the housing 257 and is supported between the front wall 259 of the housing and a disk 261 that is movable within the housing. The tow rope 248 is fixed to the disc 261, passes through the front wall 259, and changes its direction from the direction changing roller 263 to the rope rollers 251 and 253. The portion of the tow rope 248 between the turning roller 263 and the contact point 265 of the two rope rollers 251 and 253 lies in the vertical plane 50 including the pivot axis A2.

H. According to Hilpert's paper, the stand 1 is related to the weight G acting on the swivel arm at a load distance l from the swivel axis A2.
c ′ · r ′ · L = G · l
Keep balance when you are. In the equation, c ′ is a spring constant of the weight balance spring, r ′ is a vertical distance from the swing axis to the direction changing means, and L is a distance from the swing axis to the action point.
However, this condition ensures a strict weight balance only when the tow rope is running along a straight line between the contact point 265 and the action point 47. However, since the radius of the rope roller 251 or 253 is finite, the tow rope 248 is located between the contact point 265 and the action point 47, and the rope roller 253 has a circumferential surface (when the swing arm 9 turns leftward). Arc-shaped portion along the peripheral surface).
According to the present invention, in order to realize a substantially accurate weight balance even if the turning means has a finite turning radius,
c · r <(G · l) / L
Is established. In the equation, c is the spring constant of the spring 246, and the vertical distance r is the distance between the contact point 256 and the pivot axis A2.
According to the present invention, the values c and r corrected in consideration of the finite turning radius are based on c ′ and a predetermined r ′ so that the difference between r and r ′ is 0. 0 of the radius of the rope roller 251. 4 and the spring constant c is determined to be 0.8 times c ′.

1 is a schematic side view of a stand according to the present invention. FIG. 3 is a partial cross-sectional detail view of the stand as viewed in the direction of arrow II in FIG. 1. FIG. 3 is a detailed partial cross-sectional view of the stand as seen in the direction of arrow III in FIG. 2. A detailed view corresponding to FIG. 1 of the device side portion of the stand and a detailed view (B, C) of the connecting portion between the rod and the rope. Sectional drawing along line VV of FIG. 4 seen in the direction of the arrow V of FIG. 4 which shows the energy storage part of a stand. Sectional drawing corresponding to FIG. 5 which shows the energy storage part of FIG. 5 in another stand position. FIG. 7 is a cross-sectional view of the energy storage unit taken along line VII-VII in FIG. 5 as viewed in the direction of arrow VII in FIG. 5. FIG. 5 is a side view of the linear carriage / swivel device as seen in the direction of arrow VIII in FIG. FIG. 10 is a cross-sectional view of the linear carriage / swivel device of FIG. 4 or FIG. 9 along line IX-IX of FIG. 4 as viewed in the direction of arrow IX of FIG. FIG. 10 is a side view of the linear carriage / swivel device in a state in which the swivel element is swung from a vertical line as viewed in the direction of arrow X in FIG. FIG. 6 is a schematic side view of still another stand according to the present invention. FIG. 12 is a detailed view corresponding to FIG. 11 of a stand portion including an energy storage unit 245.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Stand, 3 ... Surgical microscope, 7 ... Base part, 9 ... Turning arm, 11 ... Support arm, 13 ... Equipment arm, 15 ... Holding arm, 16 ... Adjustment apparatus, 17, 19 ... Direction change roller, 21 ... Towing rope, 45 ... energy storage section, 49 ... support point, 50 ... vertical plane, 53 ... cylindrical housing, 57 ... rotary shaft, 61 ... tension bar, 65 ... compression spring, 69 ... horizontal bar, 80 ... set screw, DESCRIPTION OF SYMBOLS 81 ... Flexible rope part, 83, 85 ... Bar-shaped part, 84 ... Female screw, 93 ... Adjustment apparatus, 95 ... Energy storage part, 98 ... Rotary shaft, 101 ... Piston, 103 ... Rope, 105 ... Rope roller, 107 ... Action point 109 ... Ring-shaped stopper, 111 ... Spiral compression spring, 113 ... Bearing point, 121 ... Sliding member, 125 ... Spiral groove, 139 ... Linear carriage, 141 ... Swivel element, 145 Base part, 147 ... swivel shaft, 153 ... worm gear, 155 ... threaded spindle, 156 ... rotating shaft, 159 ... threaded spindle, 201 ... stand, 245 ... energy storage part, 246 ... weight balance spring, 247 ... action point 248 ... Towing rope, 249 ... Weight balance spring, 251 ... First rope roller, 253 ... Second rope roller.

Claims (19)

A first stand arm (11) that is pivotable about a pivot axis (A3);
A second stand arm (13) supported by the first stand arm (11) so as to be rotatable with respect to a rotation axis (A3 ′) parallel to the rotation axis (A3);
The first direction change roller (17) that is rotatable with respect to the rotation axis (A3) with respect to the first stand arm (11) and the second stand arm (13) are coupled so as not to rotate. In a stand (1; 201) having a ring-shaped tow rope (21) hung around the second direction change roller (19).
The ring-shaped tow rope (21) has a rod-shaped portion (83, 85) between the direction changing rollers (17, 19), and a stand (1; 201).   The stand (1; 201) according to claim 1, wherein the diameter of the first turning roller (17) is equal to the diameter of the second turning roller (19).   The stand (1; 201) according to claim 2, wherein the first turning roller (17) is fixed so as not to twist with respect to the pedestal portion (7) of the stand.   The stand has two rod-like portions (83, 85), and the length of the rope portion (81) located between the rod-like portions (83, 85) limits the swivel range of the first stand arm (11). The stand (1; 201) according to any one of claims 1 to 3.   The stand (1) according to any one of claims 1 to 16, wherein the rod-shaped part (85) is coupled to the rope part (81) of the ring-shaped tow rope (21) via a screw coupling part (80, 84). 1; 201).   The stand (1; 201) according to claim 5, wherein the rod-shaped part (85) has screw joints (80, 84) at both ends, the two screw joints (80, 84) having opposite directions of rotation. . It has a holding arm (15) and an adjusting device (93) attached to the holding arm (15), and the device (3) can be arranged on the adjusting device (93), and the holding arm (15) In the stand (1; 120) of the device (3) to be movably suspended so that the device (3) can be adjusted,
The stand (1; 201) characterized in that the adjusting device (93) is a linear carriage / swivel device.   The linear carriage / swivel device (93) includes a base portion (145), a linear carriage (139) that is slidable along the base portion (145), a linear carriage (139), and a linear carriage (139). The stand (1) according to claim 7, further comprising a pivot element (141) pivotable about a pivot axis (147) relative to the pivot axis (139), to which the device (3) can be fixed. 201).   A stand (1; 201) according to claim 8, wherein the linear carriage (139) is slidable along the base part (145) by means of a screw spindle (155).   The stand (1; 201) according to claim 9, wherein the axis of rotation (156) of the screw spindle (155) is perpendicular to the pivot axis (147) of the pivot element (141) and intersects the pivot axis (147).   The linear carriage / swivel device (93) is disposed on the holding arm (15) so as to be rotatable relative to the rotation axis (A4), and the rotation axis (147) is parallel to the rotation axis (A4). The stand (1; 201) according to any one of 8 to 10.   24. A stand (1; 201) according to any one of claims 8 to 23, wherein the pivot element (141) is pivotable via a worm gear device (153, 159). A first stand portion (7);
The first stand portion (7) is attached to the first stand portion (7) and has a swivel arm (9) that can swivel about the swivel axis (A2). The swivel arm (9) is movable with respect to the first stand portion (7). 2, the rotating moment corresponding to the weight load G disposed at the load distance l from the turning axis (A2) of the turning arm (9) is the turning arm (9, 11, 13, 15). A second stand part (9, 11, 13, 15) acting on 9);
A weight balancing spring (246) having a spring constant c to apply a weight balancing force to the action point (247) of the pivot axis (A2) disposed at a distance L from the pivot axis (A2); An energy storage unit (245) for balancing the weight load G, which has a direction changing means (249) arranged at a vertical distance r from the pivot axis (A2) and having a finite direction changing radius; In the stand (201) of the device (3) to be movably arranged having
In order to minimize the weight balance error caused by the finite turning radius within the wide swivel range of the swivel arm (9), the spring constant c and / or the vertical distance r is the respective theoretical weight balance target value. Smaller, as a result,
c · r <(G · l) / L
The stand (201) characterized by being.   A stand (201) according to claim 13, wherein the weight balance spring (246) is a compression spring formed as a tension spring.   The direction changing means (249) includes a rope roller (1451), and the tow rope (248) wound around the rope roller (1451) transmits the weight balance force from the weight balance spring (246) to the swivel arm (9). The stand (201) of claim 13 or 14.   The tow rope (248) includes a vertical tow rope portion between the weight balance spring (246) and the rope roller (1451), and the vertical tangent of the rope roller (1451) defined by the vertical tow rope portion is the pivot axis (A2). 16. The stand (201) of claim 15 intersecting with   17. Stand (201) according to claim 16, wherein the direction changing means (249) comprises another rope roller (1453) arranged at an equal vertical distance r from the pivot axis (A2).   The difference between the vertical distance r and the uncorrected theoretical value r ′ when the uncorrected spring constant c ′ in which c ′ · r ′ · L = G · l is established is given in advance by the rope rollers (1451, 253) The stand (201) according to any one of claims 13 to 17, which is proportional to the radius of.   The difference between the vertical distance r and the uncorrected theoretical value r ′ is 0.35 to 0.45 times, preferably 0.4 times the radius of the rope rollers (1451, 253), and the spring constant c is the uncorrected spring. 0.75 to 0.85 times the constant c ′, preferably 0. The stand (201) of claim 18, wherein the stand (201) is 8 times sds.

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