JP3472384B2 - Automatic penetration tester - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic penetration tester for investigating ground bearing capacity.

[0002]

2. Description of the Related Art Conventionally, in building various structures, it is extremely important to investigate the geology of the ground of the land and to know the ground bearing capacity of the land. Such ground geology is generally evaluated by a boring test. In the previous stage, or when constructing a small-scale building such as a house, a penetration test is conducted for a depth of up to about 15 m as a simple ground geological survey. . In this penetration test, various penetration testers that apply weight of a weight and rotational force to a penetration rod to penetrate into the ground are used. This kind of penetration tester 100 has a column 101 as shown in FIG. It has an elevating table 103 that can be moved up and down along with and can load a weight 102 of a predetermined weight. The elevating table 103 has a chuck 105 for holding a penetrating rod 104, and this chuck 105 is rotationally driven. A rotary drive source 106 such as a motor for performing the operation is arranged. At the time of the penetration test, the weight 102 of a predetermined weight is loaded on the lifting platform 103 and the penetration rod 1
04 is loaded and the rotary drive source 106 is driven to penetrate the penetrating rod 10 held by the chuck 105.
4 is rotated and penetrates into the ground, and the number of rotations of the penetration rod 104 required to penetrate this predetermined depth and the load applied at that time are measured in predetermined depth units.

[0003]

[Problems to be Solved by the Invention] In the penetration test,
A phenomenon in which the penetration rod penetrates into the ground only by the load regardless of the rotation, that is, a phenomenon generally called self-sinking frequently occurs. This is a phenomenon that occurs because the ground is soft.When this self-precipitation occurs, the drive of the rotary drive source is temporarily stopped, the load is changed as necessary, and the penetration rod penetrates into the ground only by the load. It is necessary to observe whether or not. Generally, a screw point with a sharp tip where a spiral groove is formed is attached to the tip of the penetration rod,
If the geology is soft enough to cause self-precipitation, the rod is self-rotating due to the resistance of the soil acting on the spiral groove, and it is possible to reach an accurate depth that can be penetrated only by the load. However, in the penetration tester as described above, it is common that the chuck and the rotary drive source are directly connected. Therefore, when the drive of the rotary drive source is stopped, the penetration rod has a relationship such as a reduction ratio of the rotary drive source. Therefore, the spiral groove at the screw point may stop due to the resistance of the soil even if the rod is self-rotating, and even if it is in the geological condition where it can penetrate. Therefore, even though it is a stratum that causes self-precipitation, it cannot be recognized in advance as a stratum that does not cause self-precipitation, and the danger of ground subsidence cannot be detected in advance. Is a cause that has a great influence on.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an automatic penetration tester capable of penetrating a rod in an extremely close to natural state and knowing the exact geology. .

[0005]

Means for Solving the Problems An elevating table that can be moved up and down along a column, a chuck that is rotatably arranged on the elevating table when driven by a chuck rotation drive source, and a rod that is held by the chuck. In an automatic penetration tester that has a rod and is configured to penetrate into the ground, a screw point that is screwed into the ground is attached to the tip of the rod, while a chuck that rotates the rod in the screwing direction of the screw point. Only when the rotary drive source is driven,
It is characterized in that a one-way clutch that enables rotation transmission from the chuck rotation drive source to the chuck is provided. The chuck has a rotary sleeve that is rotatable with respect to the lifting table, and a fitting member that can move in a direction orthogonal to the axis of the rotary sleeve is disposed so as to project toward the inner peripheral surface. , A sliding sleeve which is slidable along the outer circumference and keeps the fitting member always protruding toward the inner peripheral surface of the rotary sleeve, while the rod is a shaft portion which is inserted into the inner circumference of the rotary sleeve. It is preferable that the shaft portion is provided with a fitting groove into which the fitting member can be fitted. Further, the rod is provided with a replenishing means capable of replenishing the extension rod by applying rotation in the same direction as the screw point screwing direction, while the chuck rotation drive source locks the output shaft to be non-rotatable when the drive is stopped. It is preferable to provide a mechanism.

[0006]

In the above automatic penetration tester, the rotation of the screw point in the screwing direction is applied to the rod, so that the screw point smoothly penetrates into the ground by the screw action. When the chuck rotation driving source drives the rod to rotate in the screwing direction of the screw point, the drive of the chuck rotation driving source is transmitted to the chuck by the operation of the one-way clutch. Therefore, the rod is driven by the chuck rotation drive source and penetrates into the ground. On the other hand, when the drive of the chuck rotation drive source is stopped and the rod is penetrated only by the load when self-sinking occurs, soil resistance acts on the spiral groove of the screw point, and the screw action of the spiral groove causes the screw point to move to the screw point. Rotational force is generated. This rotating force is transmitted from the rod to the chuck, but the rotating direction of the chuck at this time is the screwing direction of the screw point, and due to the action of the one-way clutch, the chuck has resistance elements such as the reduction ratio of the chuck rotation drive source. It is possible to rotate without receiving it, and the rod becomes self-rotating due to the resistance of the soil, and penetrates into the ground in an extremely natural state.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 to 5, reference numeral 1 denotes an automatic penetration tester, which is a base 2 composed of two legs arranged in parallel, a support 3 vertically installed on the base 2, and a support 3 It comprises a loading platform unit 5 which can be moved up and down along with, and a control means 7 for controlling each drive part. There are various types of penetration tests, such as the standard penetration test and the Dutch cone penetration test, and the automatic penetration tester described in this embodiment is for performing a penetration test called a Swedish sounding test.

The two legs 2a of the base are connected to each other in the vicinity of the middle thereof, and the column 3 is detachably erected at this connecting portion. The support column 3 has a substantially hollow prismatic shape having an inner hollow formed by forming guide passages 3a on both side surfaces, and a guide chain 8 which is an example of a meshing member provided with a fixing attachment 8a on the back surface thereof is in a vertical direction, that is, a support column. Three
Are arranged in the extending direction.

The loading platform unit 5 comprises a lifting platform 9 which can be raised and lowered along the support column 3, a chuck portion 6 attached to the lifting platform 9, and a lifting unit 4 which drives the lifting platform 9 to move up and down. The elevating table 9 is configured by vertically projecting a guide portion 9b provided with a roller 9c in contact with the guide path 3a of the support column 3 on a frame 9a formed by connecting square members by welding or the like. It is configured to be able to move up and down along 3. Frame 9a of this lift 9
Is installed around the pillar 3, and at the rear,
The elevating unit 4 is attached, and a position detection sensor (not shown) that detects an upper limit position and a lower limit position according to the elevation of the elevating table is attached.

The elevating unit 4 has a first motor 11 which is an example of a main rotary drive source installed at the rear portion of the frame 9a, and the output shaft of the first motor 11 has a main drive bevel gear 1.
Two are connected. The first motor 11 can be driven in the forward and reverse directions and includes a lock mechanism (not shown) that fixes the output shaft so that it cannot rotate when stopped. A transmission shaft 13 having an axis orthogonal to the axis of the output shaft of the first motor 11 and a sprocket shaft 14a coaxial with the transmission shaft 13 are rotatably arranged below the first motor 11. ing. The transmission shaft 13 and the sprocket shaft 14a are connected via the speed reduction mechanism 10,
The transmission shaft 13 rotates with the rotation of the sprocket shaft 14a, and the sprocket shaft 14a also rotates with the rotation of the transmission shaft 13. A sprocket 14, which is an example of a toothed rotary member formed with a plurality of teeth that mesh with the guide chain 8 of the support column 3, is integrally attached to the sprocket shaft 14a. A powder brake 15, which is an example of a braking device capable of adjusting the brake resistance by changing the value of, is connected. This powder brake 1
Reference numeral 5 is for generating a corresponding magnetic field by applying a voltage to an exciting coil (not shown) and causing a density change in the magnetic powder (not shown) enclosed inside. The transmission shaft 1 is provided by accurate sliding torque generated by frictional action between bodies or meshing action.
3 is configured to add a brake resistance.

On the transmission shaft 13, a driven bevel gear 16 that meshes with the main driving bevel gear 12 is provided.
When the driven bevel gear 16 rotates in the same direction as the rotation of the sprocket 14 at the time of raising the loading platform unit 5 under the drive of the first motor 11, that is, Transmission shaft 13 in the opposite direction
The one-way clutch 17 is fixed only when the gear rotates, and the driven bevel gear 16 and the transmission shaft 13 rotate integrally. Further, a pulse detection sensor 18 which is an example of a detection means is provided at a position orthogonal to the rotational movement surface of the teeth of the sprocket 14, and the sprocket 1
The passage of four teeth is detected as a pulse signal, and the rotation of the sprocket 14 is detected.

The chuck portion 6 has a base 6a installed on the frame 9a, and this base 6a is provided with a speed reduction mechanism (not shown) and is an example of a chuck rotation drive source capable of forward and reverse drive. A certain second motor 19 is arranged, and a chuck 20 having an axis parallel to the axis of the second motor 19 is installed by being connected to the second motor 19 by a rotation transmission mechanism 21. The rotation transmission mechanism 21 is
A drive sprocket 23 attached to the output shaft of the second motor 19 via a one-way clutch 22, a driven sprocket 24 attached to the lower end of the chuck 20, and an endless chain 25 connecting these sprockets 23, 24, The one-way clutch 22 is driven only when the second motor 19 drives the screw point 27 described later to rotate in the direction of screwing into the ground, that is, when the driving sprocket 23 rotates in the direction opposite to the screw point 27. The output shaft of the second motor 19 and the driving sprocket 23 are integrally rotated, and the rotation is transmitted to the chuck 20.

The chuck 20 has a rotary sleeve member 20a which is rotatable with respect to the base 6a, and a storage hole 20b is provided near the upper portion of the rotary sleeve member 20a in a direction orthogonal to the axis thereof. , This storage hole 20b
A steel ball 20c, which is an example of a fitting member, is operably housed along the housing hole 20b. The steel ball 20c has a diameter larger than the thickness of the rotary sleeve member 20a, and is configured to be able to project inside and outside the storage hole 20b. A sliding sleeve 20d, which is always elastically biased upward by a spring, is fitted on the rotating sleeve member 20a so as to be slidable along the outer peripheral surface and rotatable integrally. The inner peripheral surface of the sliding sleeve 20d is formed in a stepped shape, and is configured such that the vicinity of the upper end, which is normally above the storage hole position, has a larger diameter than the other. The driven sprocket 24 and the one-way clutch 22 are mounted below the rotary sleeve member 20a.

Rotating sleeve material 20a of the chuck 20
At the time of the penetration test, the rod 26 is detachably inserted and held in the. A fitting groove 26a is formed near the upper end of the rod 26, and the steel ball 20c is fitted in the fitting groove to hold the rod 26 on the chuck 20. Further, the rod 26 is formed with a female screw portion at one end and a male screw portion that is a means for adding an extension rod to the other end. The female screw portion at one end is formed by right-handing a pyramidal material. A screw point 27 that defines the screwing direction is formed by forming a spiral groove 27a over the entire length, and the male screw portion at the other end has an extension rod of the same shape (not shown) during a penetration test. )
Is rotated in the same direction as the screwing direction when the screw point 27 is penetrated into the ground to successively add the screw point 27, and the penetration test can be continued until the screw point 27 reaches a desired depth. A loading arm 28 is provided on the base 6a so as to project forward,
At the time of the penetration test, the weight 29 of the insufficient weight is loaded on the loading arm 28 in order to set the weight of the loading platform unit 5 to 100 kgf.

The control means 7 includes a pulse detection sensor 18
And a signal from a position detection sensor (not shown) or a manual input key operation to operate the first motor 11 and the second motor 19
The pulse detection sensor 18 while controlling the driving of the
The number of pulses per predetermined time detected by the controller is compared with a preset reference number of pulses to adjust the voltage applied to the powder brake 15.
5 is configured to adjust the brake resistance. The control means 7 is also configured to process penetration test data such as the load applied to the rod 26, the number of rotations of the rod 26, and the penetration amount of the rod 26, and each data is printed out in a table format. The printer device 7a is also installed. The first motor 11 is driven by the control means 7 through the one-way clutch 17 at a speed faster than the rotation of the transmission shaft 13 when the loading table unit 5 is lowered during the normal penetration test in which no self-sinking occurs. 13 is controlled so as to idle.

When performing a penetration test with the automatic penetration tester 1, first, the first motor 11 is driven forward to raise the loading platform unit 5 to the upper limit position along the support column 3. At this time, the driven bevel gear 16 is operated by the action of the one-way clutch 17.
And the transmission shaft 13 rotate integrally, and the rotation of the transmission shaft 13 is transmitted to the sprocket shaft 14a via the reduction mechanism 10. Along with this, the sprocket 14 rotates along the guide chain 8 of the column 3 to raise the loading platform unit 5 itself. When the loading platform unit 5 reaches the upper limit position,
The driving of the first motor 11 is temporarily stopped, and the output shaft is immediately fixed by the lock mechanism. Since the sprocket 14 always receives the weight of the loading platform unit 5 and tries to rotate in the direction in which the loading platform unit 5 descends, the one-way clutch 1
By the operation of 7, the transmission shaft 13 and the driven bevel gear 16 try to rotate integrally, but since the output shaft of the first motor 11 is in a fixed state, the driven bevel gear 16 cannot rotate, and therefore the loading platform unit 5 Is stationary at the upper limit position.

In this state, the rod 26 is attached to the chuck 10 of the loading table unit 5, and the weight for setting the total weight of the loading table unit 5 to 100 kgf is used as the loading arm 2.
It is loaded on 8. After that, when the first motor 11 is driven (hereinafter, reverse driving) contrary to the driving when the loading table unit 5 is raised, the driven bevel gear 16 idles with respect to the transmission shaft 13 by the action of the one-way clutch 17. In order to
The transmission shaft 13 which has been stopped until then becomes rotatable, whereby the loading platform unit 5 starts to descend and positions the tip of the screw point 27 near the ground surface. In order to stop the lowering of the loading platform unit 5, it is only necessary to stop the driving of the first motor 11 as described above.

After positioning the screw point 27 in this way, the voltage applied to the powder brake 15 is adjusted, and the powder brake 15 adds a brake resistance to the transmission shaft 13. In this state, again the first motor 1
When the loading platform unit 5 is lowered as described above by driving 1 in the reverse direction, the screw points 27 move to the loading platform unit 5
It receives the weight of and is pushed into the ground. After that, the first motor 11 continues the reverse drive until the extension rod (not shown) is added, and rotates the driven bevel gear 16 faster than the rotation speed of the transmission shaft 13 accompanying the rotation lowering of the sprocket 14 to transmit. The one-way clutch 17 idles with respect to the shaft 13. As a result, the lowering of the loading platform unit 5 depends only on the weight of the loading platform unit 5, so that the rod 26 can be loaded with an accurate load including the weight of the loading platform unit 5. When the loading table unit 5 is lowered without mounting the rod 26 on the chuck 20, the rod 2
Since there is no penetration resistance acting on 6, loading platform unit 5
Tries to fall freely. However, at this time, the rotation speed of the transmission shaft 13 easily reaches the rotation speed of the driven bevel gear 16 at a speed higher than when the rod 26 penetrates, so that the loading table unit 5 causes the first motor 11 to move by the action of the one-way clutch 17.
It is safe because it will be lowered by the reverse drive of.

At the start of penetration, the rotation of the transmission shaft 13 is suppressed by the brake resistance of the powder brake 15 described above. The brake resistance of the powder brake at this time is
The load due to the weight of the loading table unit 5 acting on the rod 26 is set to 50 kgf. Rod 2 with this load
When the 6 cannot penetrate into the ground, the loading platform unit 5 stops, and accordingly the pulse detection sensor 18
Pulse is no longer detected. In response to this, the voltage of the powder brake 15 is adjusted, the brake resistance acting on the transmission shaft 13 is reduced, and the same state as when the load of 75 kgf is applied to the rod 26 is created. further,
When the penetration of the rod 26 is stopped under this load, the voltage load of the powder brake 15 is finally stopped and the brake resistance is released, and the rod 26 is loaded with the load of 100 kgf which is the original weight of the loading platform unit 5. To be done.

When the sinking of the rod 26 is stopped even with a load of 100 kgf, the second motor 19 is subsequently driven to rotate the output shaft in the screwing direction of the screw point 27 of the rod 26, and the rod 26 is loaded with a load of 100 kgf. In this state, rotation is applied to penetrate into the ground (hereinafter referred to as "rotational penetration"). During this rotary penetration, the load is kept at 100 kgf unless self-sinking occurs. Self-precipitation is a phenomenon that occurs when the screw point 27 reaches a soft formation, and because the load applied to the rod 26 is too heavy, the rod 26 suddenly sinks regardless of rotation. Is a phenomenon that the rod 26 penetrates.

When self-sinking occurs, the lowering speed of the loading platform unit 5 rapidly increases as the rod 26 sinks, so that the rotation speed of the sprocket 14 increases and the pulse per predetermined time detected by the pulse detecting sensor 18 is increased. The number increases. The number of pulses per predetermined time is constantly monitored by the control means 7 during the penetration test, and when the number of pulses exceeding the reference number of pulses set in advance in the control means 7 is detected, the first motor 11 and the second motor 11 are detected. Motor 1
At the same time that the driving of 9 is stopped, the voltage of the powder brake 15 is adjusted and the load applied to the rod 26 is 50 kg.
It is reduced to f. The reference for changing the load is that the number of pulses detected by the pulse detection sensor 18 is converted into the rotation speed of the transmission shaft 13, and this is driven at a constant speed by the reverse drive of the first motor 11 when the rod 26 penetrates. The time may be when the rotation speed of the bevel gear 16 matches. After that, as described above, the voltage of the powder brake is adjusted while driving the first motor 11 in the reverse direction to increase the load applied to the rod to 100 kgf, and then the second motor 19 is driven again to rotate. Make a breakthrough.

During this self-sink, that is, when the drive of the second motor 19 is stopped, the screw point 2
The resistance of the soil acts on the spiral groove 27 a of No. 7 to give a rotational force to the screw point 27. This rotational force is the rod 26
Through the driven sprocket 24 and the endless chain 25 to the driving sprocket 23. At this time, the driving sprocket 23 is rotated in the winding direction of the spiral groove 27a of the screw point 27, that is, in the screwing direction of the screw point 27, so that only the chuck 20 is freely rotated by the action of the one-way clutch 22. Therefore, the rod 26 does not receive the resistance of the second motor 19 and rotates in an extremely natural state only by the resistance of the soil acting on the screw point 27.

During the penetration test, when the loading platform unit 5 reaches the lower limit position, the driving of the first motor 11 and the second motor 19 is stopped. At this time, if the penetration test is continued, an extension rod is added to the rod 26. When adding the extension rod, first, the extension rod is screwed into the upper end of the rod 26, and then the holding of the rod 26 by the chuck 20 is released. In order to release the holding of the rod, the operator slides the sliding sleeve 20d of the chuck 20 downward to move the large diameter portion of the inner circumference of the sliding sleeve 20d to the storage hole 20b position to move the steel ball 20c. The chuck 20 is made operable, and the chuck 20 is rotated in the screwing direction of the screw point 27 while maintaining the state. At this time, the chuck 20 is the one-way clutch 2
By the action of 2, the second motor 19 can be rotated very easily without being affected by the reduction ratio of the second motor 19 and the holding release work of the rod 26 is extremely easy.

By rotating the chuck 20 while sliding the sliding sleeve 20d, the steel ball 20c is disengaged from the fitting groove 26a of the rod 26 and is pushed by the outer peripheral surface of the rod 26 so that the outer periphery of the rotating sleeve member 20a is pushed. Protruding from the surface. In this state, when the pressing of the sliding sleeve 20d is released, the sliding sleeve 20d tries to return upward due to the urging force of the spring, but at this time, the steel ball 20 is formed on the stepped portion due to the difference in the inner diameter.
The sliding sleeve 20d is prevented from rising due to the contact of c. When the first motor 11 is normally driven in this state, the loading platform unit 5 moves up to the upper limit position along the support column 3 as described above. After the loading platform unit 5 has stopped at the upper limit position, the second motor 19 is connected so as to transmit the rotation to the chuck 20.
When driven slightly, the steel ball 20c fits into the fitting groove 26a of the extension rod, which causes the sliding sleeve 20
d returns to the upper side to securely hold the extension rod. After the extension rod is replenished, the above-described operation is repeated, and the extension rod is replenished each time the loading platform unit 5 reaches the lower limit position to continue the penetration test to a desired depth.

Generally, in the penetration test, the number of rotations of the rod 26 and the load are measured in units of a predetermined depth. In the automatic penetration testing machine 1, for example, in addition to the predetermined depth, for example, a rod is used. When the control for changing the setting contents of the automatic penetration testing machine 1 which was continued, such as the change of the load applied to 26 and the occurrence of self-sink, was performed, the penetration calculated from the total number of revolutions of the sprocket 14 up to that point Amount, the number of rotations of the rod 26 counted from the control change in the previous stage, and the rod 26 obtained from the operating state of the powder brake 15.
The load and the like are printed out in a tabular form from the printer unit 7a.

In the automatic penetration testing machine 1, the winding direction of the male screw portion of the rod 26 is set in the screwing direction of the screw point 27, that is, in the opposite direction to the winding direction of the spiral groove 27a. If a lock mechanism for the output shaft such as the motor 11 is provided, the rotation of the chuck 20 in the direction in which the screw loosens due to the action of the one-way clutch 22 can be suppressed. It is preferable that the chuck 20 does not rotate even if the chuck 20 is rotated in a direction in which the rod loosens, and therefore the rod 26 can be prevented from loosening. Further, without using the driving bevel gear 12, the driven bevel gear 16, the transmission shaft 13, etc., the output shaft of the first motor 11 and the sprocket 14 are directly connected via the one-way clutch 17,
The same effect can be obtained by providing the control means so that the output shaft of the first motor 11 rotates faster than the rotation speed of the sprocket 14 when the loading table unit 5 descends. Further, even if the one-way clutch 22 is provided between the chuck 20 and the driven sprocket 24, the same effect can be obtained.

[0027]

As described above, in the automatic penetration tester of the present invention, the rotatable chuck holding the rod is provided with the sprocket, while the output shaft of the second motor is provided with the sprocket via the one-way clutch. An endless chain is wound around these sprockets, and when the second motor is driven in the screwing direction of the screw point at the tip of the rod, the one-way clutch is fixed and rotates integrally. Even so, the rod can rotate in the screwing direction of the screw point by the action of the one-way clutch.Therefore, at the time of self-sinking, the self-rotation of the rod due to the resistance of the soil acting on the spiral groove of the screw point is allowed. , It is possible to accurately measure the soft strata where self-precipitation occurs.

Further, the chuck has a rotating sleeve member which is rotatable with respect to the lifting table, and a steel ball which can move in a direction orthogonal to the axis of the rotating sleeve member is projected to the inner peripheral surface side. The sliding sleeve is arranged so as to be slidable along the outer circumference and keeps the steel ball always protruding toward the inner peripheral surface of the rotating sleeve, while the rod is the inner sleeve of the rotating sleeve. It has a shaft part that is inserted in the circumference, and since this shaft part is formed with a fitting groove into which the steel balls can be fitted, when the rod is replenished, the chuck can be rotated very easily to hold the rod. It can be released and the labor of the operator can be reduced. In addition, a lock mechanism is provided on the second motor, and by forming a threaded portion that has the same screwing direction as the screw point's screwing direction on the rod, when the chuck is rotated to release the rod, loosening between the extension rods that have been added is prevented. It is possible to prevent this, and it is possible to always perform a reliable penetration test, and it is possible to quickly stop the drive of the second motor when self-precipitation occurs, and it is possible to perform an extremely accurate geological survey.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of an essential part of an automatic penetration tester according to the present invention.

FIG. 2 is a side view of the automatic penetration tester according to the present invention.

FIG. 3 is a perspective view of an automatic penetration tester according to the present invention.

FIG. 4 is an enlarged cross-sectional view of a main part of the automatic penetration tester according to the present invention.

FIG. 5 is a perspective sectional view of an essential part of the automatic penetration tester according to the present invention.

FIG. 6 is an explanatory view of a conventional automatic penetration tester.

[Explanation of symbols]

1 Automatic penetration tester 2 bases 3 props 4 Lifting unit 5 platform unit 6 Chuck part 7 Control means 8 guide chains 9 elevators 10 Reduction mechanism 11 First motor 12 Driving bevel gear 13 transmission shaft 14 sprockets 15 powder brakes 16 Driven bevel gear 17 one-way clutch 18 pulse detection sensor 19 Second motor 20 chuck 21 Rotation transmission mechanism 22 one-way clutch 23 Drive sprocket 24 Driven sprockets 25 endless chain 26 rod 27 screw points 27a spiral groove 28 Loading Arm 29 weights

Claims (3)

(57) [Claims] 1. An elevating stand that can be moved up and down along a column, and this ascending platform.
It is rotatably arranged on the unloading table by the drive of the chuck rotation drive source.
Chuck to be placed and rod held by this chuck
In an automatic penetration testing machine having a rod and a structure configured to penetrate into the ground, a screw point configured to be screwed into the ground is attached to the tip of the rod, while the rod is rotated in the screwing direction of the screw point. Only when the chuck rotation drive source is driven , the rotation transmission from the chuck rotation drive source to the chuck is transmitted.
An automatic penetration tester, which is equipped with a one-way clutch that enables it . 2. The chuck has a rotary sleeve member which is rotatable with respect to the lift table, and a fitting member operable in a direction perpendicular to the axis of the rotary sleeve member can be projected to the inner peripheral surface side. together placed, made by providing a sliding sleeve to keep the state of protruding the slidable and <br/> always the fitting member in the rotary sleeve member periphery side along the outer periphery, whereas the rod is the rotated The automatic penetration tester according to claim 1, further comprising a shaft portion that is inserted into an inner circumference of the sleeve member, and the shaft portion is provided with a fitting groove into which the fitting member can be fitted. 3. The rod is provided with a replenishing means capable of replenishing the extension rod by applying rotation in the same direction as the screw point screwing direction, while the chuck rotation drive source non-rotatably fixes the output shaft when the drive is stopped. The automatic penetration tester according to claim 1 or 2, further comprising: