JP2502210Y2 - Automatic level - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic level equipped with an automatic optical path correction mechanism, and in particular to an automatic level equipped with a magnetic braking type optical path automatic correction mechanism in which a pendulum side braking plate is arranged facing a magnet. Regarding the level.

[0002]

2. Description of the Related Art The automatic level is, as shown in FIG.
An objective lens 2, a focusing lens 3, a focusing screen 4, and an eyepiece lens 5 are sequentially arranged on the same axis in a lens barrel 1 of a telescope, and an automatic optical path correcting mechanism 6 is provided in front of the focusing screen 4. .
This automatic optical path correction mechanism 6 is supported so that a pendulum 6a to which a reflecting mirror 7a is fixed is suspended by a suspension wire 8 and can swing, and a prism 7b is provided at a front-back position on the optical axis L sandwiching the reflecting mirror 7a. The structure is such that 7c is fixedly held on the lens barrel side, and even if the level body (lens barrel) is tilted, the pendulum 6a automatically maintains the vertical state and horizontal collimation is possible. As shown in FIG. 6, the automatic optical path correcting mechanism 6 includes a pair of magnets 9a and 9a, which are provided with a braking plate 8a fixed to a pendulum 6a and an upper frame 9 fixed to the lens barrel 1. In between
A magnetic braking mechanism is provided in which the pendulum 6a is stabilized by the swinging of the pendulum 6a, that is, the braking force generated by electromagnetic induction associated with the movement of the braking plate 8a, which impedes the movement of the braking plate 8a. Further, stopper portions 6b supported by the upper frame 9 are provided on both sides of the pendulum 6a (both left and right sides in FIG. 6) to regulate the swing range of the pendulum 6a.

However, since the space between the pendulum 6a and the stopper portion 6b is very small, moisture, dust, etc. in the air will not be absorbed by the stopper portion 6b.
A so-called “sticking phenomenon” frequently occurs, in which the pendulum 6a is stuck on the surface and does not move. The observer measures the collimation point through the automatic level telescope, but at that time, it is impossible to determine whether or not the sticking phenomenon is occurring in the automatic correction mechanism. That is, since the correction range by this automatic optical path correction mechanism corrects the change of the optical axis of about ± 15 ', the amount of change of the mechanism with respect to this is about ± 0.2 mm, and the image formation state in the field of view of the telescope can be seen. Even if they do, they often measure without realizing it. When the sticking phenomenon occurs, the swinging of the pendulum 6a, that is, the automatic optical path correcting mechanism does not operate. Therefore, it is necessary to release the sticking prior to the survey. Conventionally, the stopper portion 6b is provided with a thin needle-shaped member that is unlikely to cause sticking, and the tip of the needle-shaped member restrains the movement range of the braking plate 8, or the braking plate 8 is directly hit and sucked by this impact. Techniques such as canceling the are proposed.

[0004]

However, in the above-mentioned first prior art, although a teflon material or stainless steel is used as the needle-shaped member to reduce the adsorption action, the sticking phenomenon has not been solved. Further, in the second conventional technique, an impact may be applied to the braking plate each time it is hit, and the automatic correction mechanism may be disturbed. Further, there is a problem that it is troublesome because the operation has to be performed every time the survey is performed.

The present invention has been made in view of the above-mentioned problems of the prior art. The purpose of the present invention is to prevent the brake plate from adhering to the automatic optical path correcting mechanism without exerting an impact force thereon, and without the operator's intention. It is to provide an effective automatic level.

[0006]

In order to achieve the above object, in the automatic level according to the present invention, a pendulum body for supporting a reflecting mirror is a suspension line in a lens barrel of a telescope rotatably supported horizontally. In the automatic level with a built-in magnetic braking type optical path automatic correction mechanism in which a magnet is placed close to the suspension plate that is suspended and integrated with the pendulum body to brake the braking plate by electromagnetic induction, An air blower for injecting air into the gap between the braking plate and the magnet is provided in the lens barrel in conjunction with the horizontal rotation of the lens barrel.

According to a second aspect of the present invention, gears are attached to the vertical shaft which is the horizontal rotary shaft of the lens barrel and the fan rotary shaft of the air blower, and the vertical shaft gear is provided between the vertical shaft gear and the fan rotary shaft gear. The first driven gear that meshes with the vertical shaft gear and can roll along a circular arc-shaped slot that is concentric with the vertical shaft gear, and the rotation direction of the final driven gear that meshes with the fan rotation shaft gear is opposite The gear train and the second gear train are interposed, and the vertical shaft gear and the fan rotation shaft gear are selectively linked by the first gear train or the second gear train so that the fan of the air blower can rotate normally. It was done.

In the third aspect of the invention, the air flow passage in front of the fan is branched in the middle and extends to the air injection holes opened toward both sides of the braking plate. A self-oscillating valve that alternately switches the flow paths is provided.

[0009]

When the lens barrel is rotated horizontally by hand, the air blower operates in conjunction with the rotation of the lens barrel to inject air between the brake plate and the magnet to vibrate the brake plate. In the second aspect, the first driven gear rolls along the elongated hole based on the rotation direction of the vertical shaft gear, and the vertical shaft gear and the fan rotary shaft gear are passed through the first gear train or the second gear train. Cooperate with each other to rotate the fan rotation shaft gear forward.

In the third aspect, the self-oscillating valve provided at the branching position of the air flow path of the air blower oscillates by the air flow from the fan side to guide the air flow to the branch flow paths alternately.

[0011]

Embodiments of the present invention will now be described with reference to the drawings. 1 to 4 show an embodiment of the present invention. FIG. 1 is a vertical sectional view of an automatic level equipped with a magnetic braking type automatic optical path correcting mechanism, FIG. 2 is an enlarged sectional view of an air blower, and FIG. 3 is an air blower. FIG. 1 is a plan view of the fan drive mechanism of FIG.
FIG. 4 is a perspective view of the self-oscillating valve.

In these drawings, reference numeral 10 is a lens barrel of an automatic level telescope, and in the lens barrel 10, an objective lens 12, a focusing lens 14, an afocal lens 15, an automatic optical path correcting mechanism 16 and a focus are arranged in order from the front. The plate 17 and the eyepiece lens 18 are arranged on the same axis, and the axis passing through the center of the objective lens 12 is the optical axis L. The automatic optical path correction mechanism 16 includes a plate-shaped upper frame 20 screwed into the lens barrel and a pair of prisms 2 fixed to the upper frame 20 by a prism holding frame 23a.
3, 23, a plane mirror 24 fixedly supported by a gate-shaped pendulum body 22 suspended from the upper frame 20 by suspension lines 22a, and provided on both sides of the pendulum body 22 fixed to the upper frame 20. Stopper 20a that determines the swing range of the pendulum body 22
And a magnetic braking mechanism 30 for braking the pendulum body 22.

The upper frame 20 is formed with an opening 21 extending in the front-rear direction (front-rear direction of the optical axis), and a braking plate 32 fixed to the upper end of the pendulum body 22 penetrates through the opening 21 and projects upward. Has been done. In addition, the brake plate 3 is provided on the periphery of the opening 21.
A pair of magnets 34, 34 are provided so as to sandwich 2 and the braking plate 32 moves in the magnetic field formed by the opposing magnets 34, 34, so that an eddy current is generated in the braking plate 32 by electromagnetic induction. A braking force that hinders the movement of the braking plate acts, so that the braking plate 32 is braked. That is, the braking mechanism 30 is configured by the magnets 34, 34 and the braking plate 32. The braking mechanism has already been disclosed by the applicant and is publicly known. Rare earth magnets are arranged in parallel on one side facing the braking plate, and the magnets are connected by a ferromagnetic material (for example, an iron plate). It may be a structure. A pair of air injection holes 51, 51 of an air blower 50, which will be described later, are arranged in the upper frame 20 toward the gap between the magnets 34, 34 and the braking plate 32 (see FIG. 2). A balancer 33 for swinging the pendulum body 22 in a well-balanced manner is provided above the braking plate 32. Reference numeral 20b is a Teflon material provided on the contact surface of the pendulum body 22 with the stopper 20a for preventing sticking.

A disk-shaped skirt portion 11 is provided below the lens barrel 10.
Are integrally formed, and a vertical shaft 28 integrated with the lens barrel 10 is provided in the skirt portion 11. Vertical axis 2
8 is supported by a shaft cylinder 42 integrally formed on the parallel surface plate 40, and the parallel surface plate 40 is supported by a leveling table 70 for leveling. The spacer 43 and the corrugated leaf spring 4 are provided on the outer periphery of the shaft cylinder 42.
4, a spur gear 45 is assembled in a horizontal state in which it is elastically pressed in the vertical direction, and a worm 48a of a worm shaft 48 that extends horizontally through the disc-shaped skirt portion 11 meshes with the spur gear 45. . Therefore, when the worm shaft 48 is rotated by holding the knob 49 provided at the end of the worm shaft 48, the rotation torque of the elastic support portion of the spur gear 45 becomes smaller than the rotation torque between the vertical shaft 28 and the shaft cylinder 42. Since it is also large, the worm 48a moves around the spur gear 45 while rotating. That is, the lens barrel 10 can be rotated (slightly moved) with respect to the parallel surface plate 40. Further, since the lens barrel 10 and the spur gear 45 are integrally formed in the circumferential direction via the worm shaft 48, when the lens barrel 10 is grasped and rotated by hand, the lens barrel 10, the spur gear 45, and the vertical shaft 28. And smoothly rotate (coarse) around the shaft cylinder 42. Further, the lens barrel 1 is provided between the barrel 42 and the skirt 11.
A rotary encoder 80 is provided to detect a rotation amount of 0.

Further, a spur gear (hereinafter referred to as a vertical shaft gear) 46 is attached to the vertical shaft 28, and a spur gear (hereinafter referred to as a fan rotary shaft gear) 5 is also attached to a fan rotation shaft 54 of the air blower 50.
8 is pivotally mounted, and the vertical shaft 28 is provided between the gears 46 and 58.
A gear mechanism 60 including a pair of gear trains 60A and 60B for transmitting the normal / reverse rotation of 1 as the normal rotation of the fan 53 of the air blower 50 is interposed. The gear mechanism 60 includes a first gear train 60A and a second gear train 60B that share a first driven gear 61 that meshes with the vertical shaft gear 46. In the first driven gear 61, the shaft 61a is supported in the arc-shaped elongated hole 62 that follows the outer periphery of the vertical shaft gear 46, and
The rotation of the hard shaft gear 46 allows the hard shaft gear 46 to roll along the outer peripheral edge of the elongated hole 62 while maintaining the meshed state with the vertical shaft gear 46. Therefore, when the vertical shaft gear 46 is rotated clockwise in FIG.
Along the direction of arrow A, meshes with the second driven gear 63 of the first gear train 60A at the position of the long hole end 62a, and the rotational force is transmitted to the fan rotation shaft gear 58 via the first gear train 60A. This is transmitted to rotate the fan 52 in the forward direction.
On the contrary, when the vertical shaft gear 46 is rotated counterclockwise in FIG.
The driven gear 61 rolls in the direction of arrow B along the long hole 62,
At the other end 62b of the long hole, the second driven gear 64 of the second gear train 60B meshes with the first gear train 60A.
More gears (gear 65) are transmitted to the fan rotation shaft gear 58 via the second gear train 60B having one more gear, and rotate the fan 53 in the forward direction (direction in which air is sent to the front of the flow path). As described above, in this embodiment, the first driven gear 61 is replaced by the second driven gear 63 or 6 depending on the rotation direction of the hard shaft gear 46.
4, the first gear train 60A or the second gear train 60B is engaged with the hard shaft gear 46 and the fan rotation gear 58 to rotate the fan 53 forward. Therefore, the structure is such that the air blower 50 operates when the lens barrel 10 is horizontally rotated in either forward or reverse directions.

The air flow path in front of the fan of the air blower 50 is divided into two in the middle as shown in FIG.
The respective branch pipes extend to the air injection holes 51, 51, and the branch portion 52 is provided with a self-oscillating valve 56 for switching the air flow path. That is, as shown in the enlarged view of FIG. 4, the self-oscillating valve 56 is supported in a Y-shaped vertical cross-section with the Y-shaped opening side located upstream of the air flow path and supported by the rotation of the fan 53. When the airflow hits, it is unbalanced and swings in the flow path, whereby the airflow is alternately supplied to the branch path. For this reason, air is alternately ejected from the air ejection ports 51, 51 to vibrate the braking plate 32, and the suction of the braking plate is released. Note that in surveying using the automatic level, the operator customarily rotates the lens barrel 10 before starting the survey, and at the same time as this conventional act of rotating the lens barrel performed by the operator, The suction is released.

When the fine movement knob 49 at the end of the worm shaft is rotated, the lens barrel 10 and the rigid shaft gear 46 rotate integrally, but this rotation speed is low, and therefore the fan 5 of the air blower 50 is rotated.
Since the rotation speed of 3 is also slow, a strong air flow that vibrates the braking plate 32 is not formed, and the action of the automatic optical path correction mechanism 16 is not hindered.

[0018]

As is apparent from the above description, according to the automatic level of the present invention, when the lens barrel is horizontally rotated by hand, the fan of the air blower rotates in association with the rotation of the lens barrel. Since the braking plate is vibrated by injecting air, it is possible to prevent the braking plate from adhering to the lens barrel, which is conventionally performed before the surveying.

[Brief description of drawings]

[Fig.1] Vertical section view of automatic level

FIG. 2 is an enlarged sectional view of an air blower.

FIG. 3 is a plan view of a fan drive mechanism of an air blower (a sectional view taken along line III-III shown in FIG. 1).

FIG. 4 is a perspective view of a self-oscillating valve provided in a branch passage of an air blower.

FIG. 5 is a vertical sectional view of a conventional automatic level.

FIG. 6 is a perspective view of a conventional magnetic braking type optical path automatic correction mechanism.

[Explanation of Codes] 10 Telescope lens barrel 16 Optical path automatic correction mechanism 22 Pendulum body 22a Suspended wire 24 Reflector 28 Vertical axis 30 which is a horizontal rotation axis 30 Magnetic braking mechanism 32 Braking plate 34 Magnet 42 Vertical axis shaft bearing section 46 Vertical gear 50 Air blower 51 Air injection hole 53 Fan 54 Fan rotating shaft 56 Self-oscillating valve 58 Fan rotating shaft gear 60 Gear mechanism for driving the air blower 60A First gear train 60B Second gear train 61 First driven gear 62 Long Hole 63,65 Final driven gear

Claims (3)

(57) [Scope of utility model registration request] 1. A pendulum body for supporting a reflecting mirror is suspended by a suspension line in a lens barrel of a telescope rotatably supported horizontally, and a magnet is approached to a braking plate integrated with the pendulum body. Is disposed, and an automatic level with a built-in magnetic braking type optical path automatic correction mechanism for braking the braking plate by electromagnetic induction is provided, in the lens barrel, between the braking plate and the magnet in conjunction with horizontal rotation of the lens barrel. An automatic level characterized by having an air blower for injecting air into the gap between. 2. A gear is attached to each of a vertical shaft, which is a horizontal rotation shaft of the lens barrel, and a fan rotation shaft of an air blower,
Between the vertical shaft gear and the fan rotation shaft gear, the first driven gear that meshes with the vertical shaft gear and can roll along an arc-shaped slot concentric with the vertical shaft gear is shared, and the fan rotation is performed. A first gear train and a second gear train in which the final driven gear meshing with the shaft gear has a reverse rotation direction, and the vertical shaft gear and the fan rotation shaft gear are either the first gear train or the second gear train. 2. The automatic leveler according to claim 1, wherein the fan of the air blower is normally rotated by being selectively linked with each other. 3. An air flow path in front of the fan is branched midway and extends to an air injection hole opened toward both sides of the braking plate, and the air flow paths are alternately arranged at the branch portions of the air flow path. 2. The automatic level according to claim 1, further comprising a self-oscillating valve for switching to.