JPS5926892A - Method of overhanging and housing extension jib in wheel type crane - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for extending a supplementary jib in a wheel crane such as a truck crane or a rough terrain ink 1/-
This relates to a storage method.

The replenishment jib that is attached to the telescopic boom in a wheeled crane is constructed by using a truss-type cantilever jig with a truss structure and a large number of connecting rods between the side rods made of a pair of square pipes, etc. A suspension rod support compression column type jib (hereinafter referred to as "kori") with a flat shape and a suspension rod.
These are simply referred to as truss type jigs and compression column type jibs).
There are several types, and among these, the latter compression column type jib is said to be advantageous in terms of manufacturing cost and weight. On the other hand, the method of storing this additional jib is generally to move the jib below the boom.
There are two types: a bottom-holding type that folds into a l-shape, and a side-holding type that folds on the side of the boom. In this double retractable force type, in the case of the lower holding type, the thickness of the boom and jib in the vertical direction becomes large, so the visibility during traveling, especially the side visibility, becomes narrow. In addition,
Attempting to improve visibility increases the overall height of the crane vehicle, which also poses a problem when traveling. on the other hand,
In the case of the side-carrying type, the thickness in the lateral direction becomes larger by m1%, which widens the side visibility, which poses a problem in that it becomes difficult to turn on narrow running roads.

Therefore, in the past, in order to ensure both side visibility and running performance in narrow spaces, when using a compression column type jib, a 5VC was designed with a lower hold storage system in consideration of running performance in narrow spaces, and a truss type jig was used. In some cases, a horizontal storage system is adopted in consideration of side visibility, but the reality is that it is not a fundamental solution as it leaves problems with either one of them.

In terms of extending and retracting the jib, in the horizontal holding method, the jib is held on a horizontal plane from the side to the front.
In order to rotate it 80 degrees, a large space must be secured on the sides. With the folded under-hugging method, it was extremely troublesome to rotate the jib 180 degrees from bottom to top and pass the main hook between the jib feet when extending.

The present invention has been made in view of the two circumstances, and is capable of reducing the vertical and horizontal thickness to a minimum in the retracted state, thereby ensuring both side visibility during driving and performance in narrow spaces. Moreover, it is an object of the present invention to provide a method for extending and storing a supplementary jib in a wheeled crane, which allows the work of extending and storing the jib to be easily performed even in a narrow space.

The present invention basically adopts a side-hugging storage method for a compression column type jib, and is characterized by folding the jig on the side of the boom in a vertical position with its thickness direction facing left and right when storing it, and then extending it out. Sometimes, the jib is suspended in a vertical position and then twisted and rotated around an axis along the axis of the jib, thereby converting the jib into an extended position with its thickness direction facing upward or downward. In addition to this, in the process of retracting the jib from the extended position, when the jig is twisted in the opposite direction to the above-mentioned extended position, the rotation angle is automatically adjusted to match the retracted position. It is also characterized by the fact that it is regulated.

Hereinafter, uninvented embodiments will be described with reference to the drawings.

Figures 1 and 2 show the jib extended state, Figures 3 to 5
The figure shows the jig stored state. 1 is a telescopic boom, 2 is a suspension rod supported compression column type supplementary jib (hereinafter simply referred to as a jib), and 3 is a suspension rod. In addition, here, in order to make the explanation easier to understand,
A base end boom I as a boom element constituting the telescopic boom 1
Only A and tip boom IB are shown, but in reality,
In many cases, the boom is constructed in a multi-stage telescoping type in which one to several stages of intermediate booms are interposed between the base end and tip face booms LA and IB, and the present invention is applicable regardless of the number of boom stages. can do. Also, the left and right direction below is
This refers to the direction seen from the driver's seat.

As is well known, the jib 2 has a large number of connecting rods 2C fixed between a pair of side rods 2a, 2b made of flat square pipes, etc., and is formed into a flat frame with a curved tip. are doing.

There are boom point pins 4 on both left and right sides of the tip of the boom 1, that is, the tip of the tip boom IB (boom point).
．． 5 can be rotated around the pin axis X by 1'im,
When the jib is extended, the left and right feet 6.7 of the jib 2 are engaged with the boom point pin 4.5. Note that both the left and right jib feet 6.7 are formed into a bifurcated shape. The left side jib foot 6 is formed into a fork shape in which the lengths of the three pieces forming the bifurcation are equal, and the right side jib foot 7 is formed into a stepped fork shape in which the length of the - piece is shorter than the other pieces. is forming. These two jib feet 6.7 are formed separately from the jib body, that is, the side rods 2a and 2b, and the right jib foot 7 is located at the base end of the right side rod 21. - As shown in FIG. 6, the left side jib foot 6 is navy blue and has an integral threaded portion 6a, and this socket 61 is fixed inside the proximal end of the left side rod 2a of the jib. i'votl & combined. In this way, the left side jig foot 6 is fitted with respect to the base end of each of the nine jibs 1 and 2a so as to be screwed around the axis yt of the side rod. In addition, the right side jib foot 7
has a pin hole 9 in one place, and a tip 1η in the left jib foot 6.
41 and the middle 17 ((), pin holes 8a and 8b are provided at two locations, and the pin hole 8b in the middle part is formed in the shape of a long hole.

The boom point pins 4, 5Vrc on both the left and right sides also extend through pin holes 4a, 5a in the radial direction.

As shown in FIGS. 3 to 5, the jib 2 is folded along the left side of the base end boom IA in a vertical position with its thickness direction facing left and right when stored. In this case, as shown in FIG. 5, the boom tip (the boom tip one stage below the tip boom in the case of a multi-stage boom) VC is provided with the boom extension sheep 10 in a vertical posture inclined at a predetermined angle. In order to prevent the sheave 10 and the jib 2 from interfering with each other in the jig retracted state IM, the jib 2 is stored in an inclined position at an angle α (for example, 15°) equal to the inclination angle of the sheave 10. By the way, as another means of avoiding interference between the jib 2 and the boom extension sheep 10, the jib 2 can be stored in a vertical position at a position optically separated from the boom 1. In such a case, the boom point pin 4 is There is a problem that the jib 2 has to be made much longer and thicker than the conventional one, and the amount of protrusion of the jib 2 toward the pool I11 becomes large. It should be noted that illustrations of the boom extension sheep lO are omitted except in FIG. 5.

Moreover, FIG. 3.4 is shown ignoring the inclination of the jib 2.

However, at L7, with the jib 2 retracted at the predetermined inclination angle α as described above, the left jib foot 6 and the left rod 2a are
Specify the relative position in the circumferential direction of , in other words, both 6, 2a
Preset mechanism 1 for holding relatively unrotatable
1 is provided between this jib foot 6 and the base end of the left side rod 2a. That is, as shown in FIG. 7, a plate-shaped bracket 12 is fixed to the lower surface of the left jib foot 6, and a cylindrical bracket 13 is fixed to the lower surface of the base end of the left rod 2a so as to face each other in the jig axis direction. The cylindrical bracket 13 has a tip of 1 yen.
1 is provided with a pin 14 that can freely move in and out along the jig axis direction, a spring 15 that always presses the pin 14 toward the plate-shaped bracket 13, and a spring receiver 16. The base end of the bottle 140 penetrates the spring receiver 16 and protrudes to the outside, and a lever 17 having a knob 17a is attached to the base end, and the lever 17 is connected to the outer end surface π of the spring receiver 16. It is in contact. The outer end surface of the spring receiver 16 has a low surface portion 16a and a high surface portion 16b, and these both surfaces 16a and 16b are formed into a cam surface connected by an inclined surface 16c. The tip of the pin 14 protrudes toward the plate-shaped bracket 12 at the contact point, and the bracket is closed!
-121C engaged with the provided pin hole 12a, rotated the 5 reno'-17 in the circumferential direction along the inclined surface 16c as shown by the imaginary line in FIG. At this time, the tip of the bottle 14 is configured to sink into the cylindrical bracket 13.

On the other hand, in the retracted state, the jib 2 is fixed to the proximal poom IAVc at two locations, the distal end and the proximal end.

That is, first, to explain the fixing mechanism on the jib tip side, as shown in Figs. 1 to 4 and Figs. Base 1'7: On the left side of the base end of Af poom IA, both sides of the boom in the direction of the boom are open [1] A box-shaped bracket 19 is protruded, and a retaining pin is installed. 8 is engaged with this bracket 19 [/i:iQ side and suspended. The bracket 19 and the engagement pin 18 have pin holes 19a and 18a that match vertically when the jig is stored.
are provided, and the tip fixing pins 20 are inserted into the pin holes 19a and 18a.
is inserted to fix the engaging pin 18 to the bracket 19Vc so that it hangs. On the other hand, the fixation of the base end of the jib is
16 '4FIc As shown, the bracket 2 with a pin legend protrudes from the side of the base end boom IA and the jig left lever 2a.
1.22 are connected to each other with a base end fixing pin 23.

Reference numeral 24 denotes a jib guide, which is formed by fixing a pair of guide frames 24a, 24a in parallel to the left side surface near the tip of the proximal seam IA, as shown in FIG. 10.11. This jib guide 24 has a horizontal groove part 241) along the zoom axis direction and an inclined groove part 24'c
It consists of 25 is a guide pin as an engaging body on the jib side that engages with this jib guide 24, and is attached to the right side rod 2bV.
cProtruding.

26.26u Suspension rod storage W is provided to protrude upward from the left and right side rods 2a, 2bVrc at the tip of the jib 2, and one end of the suspension rods 3, 3 is attached to this ffX (= It is fixed to the J seat 26.26 with pins 27.27.In order to store the suspension rods 3, 3 in the jib 2 when storing the jib, there are L-shaped holes on both the left and right sides of the base end of the jib 2. Rod holders 29, 29 are provided on both the right and left sides of the middle part of the jib 2.
As shown in FIG. 3, it consists of a U-shaped holder main body 30, an opening/closing link 31 that opens and closes the upper opening of the Honda 30, and a threaded spring 32 that always biases the link 31 in the direction of closing the main body. When stored, the opening/closing link 31 closes the main body 30 to hold the rod 3, and when the rod is used, the link 31 is opened to remove the rod 3 from the main body 30 and hang it. 30a is a pin that holds the opening/closing link 31 in an open state.

Reference numeral 33 indicates jib twist handles provided on both left and right sides of the tip of the jib 2.

Next, a method for extending and storing the jib 2 according to the present invention will be explained.

The jib 2 is in the retracted state as shown in FIGS. 3 to 5.
In the extended state, the right side rod 2b is on top and the left side rod 2a is on the bottom, and in a vertical posture inclined at a predetermined angle α, align it with the left side of the proximal end pool IA, and in this state, insert the engagement pin at the tip of the jig mentioned above. 18 is engaged with the bracket 19i/C at the proximal end of the proximal poom IA and fixed with the tip fixing pin 20, and at the proximal end, the bracket 19i/C is attached. , 22 with the base end fixing pin 23, the jib 2 is fixed in the retracted position. Further, in this jib retracted state, the guide pin 25 of the shifter 2 is engaged with the horizontal portion 24b of the shifter guide 24. Furthermore, the pin 14 engages with the bottle hole 12a in the preset machine groove 11Vtc provided between the left side jib foot 6 and the base end of the left side rod 2a,
Relative rotation between the jib foot 6 and the left rod 2a is stopped. Therefore, the jig 2 is extended by the following procedure.

(b) With the crane outrigger (not shown) extended to stabilize the aircraft, fully retract the boom 1 and point it to the side or rear of the aircraft in a horizontal position.

Offshore) As shown in FIG. 14, remove the jib tip fixing pin 20 and insert the pin 20 across the pin hole 4a of the left boom point pin 4 and the intermediate pin hole 8b of the left jib foot 6. This connects the left jib foot 6 and boom point pin 4, and repurposes the jib tip fixing pin 20 as a jib foot pin. Also, at this time, the pin 14 of the preset machine groove 11 should be bent.
17, the bottle hole 12 is opened as shown by the imaginary line in FIG.
a, so that the left side rod 2a- freely rotates around the jig axis y and hangs.

e→ Remove the jib base end fixing pin 23. This pin 23 will later be used as a foot pin for the right jib foot 7.

(to) Turn the boom to 80° as shown in Figure 15.16.
Raise the same pool 1 with a twister, and place it on the guide pin 2.
5 is removed from the jib guide 24 (about 60 cm). This causes the jib 2 to rise together with the tip zoom IB, and the guide pin 25 of the jib 2 to be attached to the proximal boom IA.
In the jig guide 24, it enters the inclined groove part 24c from the horizontal groove part 24b and moves in the inclined groove part 24c. As a result of and h, the jib 2 rises and rotates VC forward about the axis X of the boom point pin 4, detaches from the base end boom IA, and assumes a vertical posture.

(e) Next, tilt down zoom 1 and move the jib tip (lower end)
Lower the handle 33.33 to a height where it can be operated from the ground.

(to) Holding the handle 33.33, twist the jig 2 around the jig axis (vertical axis) yt by 255 degrees (from the state shown in Fig. 16 to the state shown in Fig. 18), and move the right jig foot 7 to the right boom point. 5.

In this way, since the jib 2 is twisted and set at the tip of the boom, the main hook (not shown) suspended from the bottom of the boom tip sheep block 34 can be easily passed over the base end of the jib 2. I can do it. Alternatively, if you lower the main hook to the ground in advance at this time, you only need to change the hanging wire of the hook, so you can pass the main hook through the base end of the jig when extending the jig, as in the case of the conventional lower holding type. You will no longer have to struggle with your work.

(g) Fix the tip of the auxiliary winding wire 36 passed through the auxiliary sheep 35 of the tip boom IB to the tip of the jib 2, and wind the auxiliary winding wire 36 so that the jib tip is about 1 m above the ground. 1, or while extending the tip boom IB, lower the boom 1 further.

(Then) After lowering the boom 1 horizontally or slightly above and below, insert the previously removed jig base end fixing pin 23 into the bin hole 9 of the right jib foot 7 and the right boom point pin 5 as shown in FIG. This prevents the jib foot 7 from coming off the boom point pin 5.

In addition, once remove the jig tip fixing pin 20 inserted into the pin holes 8b and 4a17m of the left jib foot 6 and left boom point pin 4 in (b) above, and insert the same pin 20 into the tip of the jib foot 6 as shown in FIG. Replace it with the pin hole 8a. When replacing the pin 2o, the pin 20 can be easily removed since the intermediate pin hole 8b of the left jib foot 6 is made into a long hole. In this manner, the left jib foot 6 and the left boom point pin 4 are brought into close contact when the jig is extended.

(S) Remove the JL [a round and intermediate portions of the suspension rods 3, 3 from the rond receiver 28.28 and the rod holder 29.29, and attach the base end of the rond to the sheep block 34 of the tip boom lB as shown in Fig. 21. How many J-wrestling matches are there?

In this case, the jib 2 is supported by suspending the suspension rods 3, 3 between the jig 2 and the tip boom IB.

b) Pass the auxiliary winding wire 36 through the sheep block 37 of the jib 2, and attach the auxiliary hook 38 to its tip.

As described above, the extension of the jib 2 is completed.

The unfurled jib 2 is stored in the reverse order of the above-mentioned extension. To summarize the main points, the boom 1 is tilted horizontally or slightly downward, and the fully retracted position is slightly extended (for example, 60 to 70 cm).

Next, after removing the auxiliary winding wire 36 from the auxiliary hook 38 and fitting its tip into the jib tip, the wire 36tl';
While holding 7'2, suspend the suspension rod 3.3.
Remove and store in jib 2. Then, the jig tip fixing pin 20 used as the left jib foot pin is re-inserted in the same way as when it was stretched out (in the opposite direction), and the jig base fixing pin 23 is removed from the right jib foot 7. Also, at this time, the preset machine Fj/j 11 pins 14 protrude from the cylindrical bracket 13. After fixing, loosen the auxiliary winding wire 36 while raising the zoom 1 (or, extend the tip boom IB by about 2 m in advance and 113), the jig 2 is rotated downward to hang in a vertical position, and the jib 2 is then rotated about 255 degrees about the axis yt with the left jib foot 6 as a fulcrum (the state shown in Fig. 16). When the jib 2 is rotated approximately 255 degrees, the preset mechanism 1 will open as shown by the solid line in Figure 7.
1 pin 14 is attached to the plate-shaped bracket 1 on the left side jib foot 6 side.
21/n is engaged with the pin hole 12a provided, thereby preventing the jig 2 from further rotation. That is, the relative circumferential position of the jib left rod 2a and the left jib foot 6 is returned to the positional relationship in the jig storage state, and the jib 2 is automatically preset to a posture corresponding to the stored posture.

Therefore, after this, if the poom 1 is raised by about 80 degrees and fully retracted, and the jig 2 is drawn to the side surface of the base end boom IA by the guiding action of the guide pin 25 and the jib guide 24, the jib 2 will be automatically moved. , a predetermined angle (I
It will be set in a vertical position inclined at an angle of 15 degrees (for example, 15 degrees). That is, the jib 2 may interfere with the zoom extension sheep 10 in the retracted state because the jig 2 is rotated too much during the twist rotation about the jig axis y, or
Conversely, due to insufficient rotation, the guide pin 25 is
There is no fear that the jig will get stuck in or become stuck in the jig 4, and a predetermined stored state of the jig can be reliably and easily obtained. In this state, the jib 2 is fixed in the stored state by setting both the tip and base fixing bins 20.23.

The preset mechanism 11 not only functions to preset the retracted posture of the jib 2 described above, but also stores the jig 2 and
When expanding and retracting the poom 1 with the left jib foot 6 and the poom point pin 4 separated, the left jib foot 6 unexpectedly rotates due to shaking and the circumferential positional relationship with the zoom point pin 4 becomes out of order. It also has the effect of preventing it from being put away.

As mentioned above, when using the uninvented method, the jib 2 is stored along the poom 1 in a vertical position with its thickness direction facing left and right. The total thickness dimension in the direction can be minimized.

Of course, the thickness in the vertical direction can be reduced to a minimum of just the thickness of the boom. Therefore, it is possible to simultaneously ensure the side visibility while driving and the ability to run in narrow spaces at Vrc.

Furthermore, when extending and retracting the jig 2, the jib 2 is placed in a vertical position and twisted around the vertical axis yt, thereby changing from the vertical position (position when stowed) to the horizontal position (position when extended) or vice versa. Since the position can be changed, there is no need to secure a large space for turning the jig on the side as in the conventional method, even though the jig is stored horizontally, and the jig 2 can be easily extended and stored even in a narrow space. can.

The axis line y'' in the jig storage process!, the preset mechanism 11 rotates the jib 20 times 1 during the twist rotation.
31 to automatically pre-nut the jib 2 to a posture corresponding to a predetermined storage posture, the jig storage work can be made more efficient, and even after the jig is stored, the left jib foot 6 can be adjusted by the same mechanism 111c. Due to the anti-rotation action, the foot 6 can be held in a posture compatible with the zoom point pin 4Vtc.

In addition, in the embodiment 1-, the left foot 6 of the jib 2 is twisted to rotate the axis yt, ! Although the structure is configured such that the screw rotation structure is rotated at 30 degrees, a bearing structure may be adopted instead of the screw rotation structure. Regarding the bent right side jib foot 7, in the above embodiment, one of the two pieces was formed into a short stepped bifurcated shape, but as shown in FIG. It may be formed into a bifurcated shape. If the jib 2 is deviated from this shape, the jib 2 will be suspended in a vertical position and rotated with a twist, and if the jib 2 is tilted so that the right jib foot 7 is located below the right poom point pin 5 due to the jig center of gravity, the By dragging the jib foot 7 to the right zoom point pin 5, both 7 and 5 can be temporarily connected. In addition, the basic embodiment in which the right jig foot 7 is formed into a stepped bifurcated shape simplifies the operation of securing the foot 7 to the boom point pin 5, but the right jib foot 7 is the same as the left jig foot 6. Even when the two pieces are formed into a bifurcated shape with equal length, the intended purpose of the present invention can be fully achieved. - At the preset mechanism 11 V'rC, in the second embodiment -: Conversely, the bracket 12 with the pin hole 12a is connected to the jig main body side r1 pin 1.
4 and a bracket 13 provided with a notch 15 may be provided on the jib foot 6 side Vrc.

As mentioned above, according to the great invention, even though the jib is horizontally retracted, 2 can be achieved by minimizing the horizontal thickness dimension of the boom and jig in the retracted state. While maintaining good side visibility, it is also easy to enter into narrow spaces.Furthermore, the jig can be easily extended and stored even in narrow spaces.Especially, the twist rotation of the jib axis during the retracting process In some cases, the preset mechanism can regulate the rotation amount of the jig and automatically preset the jig to a posture corresponding to a predetermined storage posture, making the jig storage work more efficient. The preset mechanism prevents the foot from rotating so that the foot can be held in a position that matches the boom point pin.

[Brief explanation of drawings]

The figure shows an embodiment of the great invention, and the first figure shows a jig overhang! A side view of the island, Figure 2 is a plan view of the island, Figure 3 is a side view of the jib in its retracted state, Figure 4 is a plan view of the island, Figure 5 is an enlarged sectional view taken along the line ■-■ in Figure 4, Figure 6 is an enlarged perspective view of the jib foot part, Figure 7 is an enlarged sectional view of the preset mechanism, and Figure 8 is an enlarged perspective view of the jib foot part.
Figure 9 is an enlarged view of part A, Figure 9 is a sectional view taken along the line IX-IX in Figure 8, Figure 10 is an enlarged view of the construction part in Figure 3, and Figure 11 is the
Figure 12 is an enlarged view of Figure 4. 14(b) is an enlarged view of the left side jig foot in the VC circle state, and FIG. 15 is an enlarged side view of the guide mechanism in the middle of moving the jig toward the vertical position. Figure 16 is a schematic side view of the same jig hanging in a vertical position, Figure 17
The figure shows a schematic side view of the jig rotated by about 165 degrees, and FIG. 18 shows a schematic side view of the jig rotated by about 90 degrees. FIG. 21 is a schematic side view showing the fully extended state, and FIG. 22 is a side view showing a modified example of the right jib foot. 1... Telescopic boom, IA... Base end (fixed) boom,
IB... tip (movable) zoom, 2... jig, 3...
・Suspension rod, 4.5... Boom point pin, 6... Left side jib foot, 7... Right side jig foot, 11... Preset mechanism, 12... Jib foot side bracket, 12a... Pin hole, 13... Jib body (111, 1 bracket, 14... pin, 15...
・Spring, X...Boom point pin axis, Y...Jig axis direction axis. 4f Patent Applicant: Kobe Steel, Ltd. No. M7 1/Drawing Procedure Amendment (Reprint June 7, 1982 1, Incident Indication 1982 Patent Application No. 61986 Jib Extension and Retraction Method 3, Amendment Relationship with the case involving a person who does
No. 3 New Matsuoka Pill 6, subject of amendment Z Contents of amendment (1) In the first line of page 16 of the specification, the phrase ``lower'' is corrected to read ``1 downward.'' (2) On page 16 of the specification, line 14 and all lines 15, “
(3) Correct figure 2 of the drawing as shown in the attached appendix.

Claims (1)

[Claims] 1. Equipped with a telescoping boom and a suspension rond support compression column type replenishment jib that is attached to the tip of the telescoping boom. In a wheel-type crane that is supported by a boom point pin installed in a horizontal position along the boom point pin so as to be able to rotate about the pin axis dimension, the jib feet on both left and right sides of the above-mentioned replenishment jib are attached to the above-mentioned both zoom point pins. The jib foot is formed into a bifurcated shape that can be engaged and detached from the jib body, and one jib foot can be rotated about the axis along the jib axis direction with respect to the jib body (q), and the other jib foot is fixed to the jib body, Brackets are provided facing each other on the rotatable jib foot and the jib body, and one bracket is provided with a pin that can freely move in and out along the jig axis direction, and a spring that presses the pin toward the other bracket. , the other bracket) l'fi constitutes a preset mechanism that regulates the relative position of the jib foot and the jib body in the circumferential direction to a constant by providing a hinge pin hole in which the pin engages, and when the jib is stored, the jib When extending the jig, hold it in a vertical position with its thickness facing left and right, and when extending the jig, keep the rotatable jib foot secured to the corresponding boom point pin. , Rotate the jib around the axis of the boom point pin to hang it in a vertical position, and in this state rotate the jib around the jib axis to engage the fixed jib foot with the corresponding boom point pin. By this,
In the process of extending the jib to the tip of the boom in a flat position, and retracting the jib in a predetermined vertical position on the side of the boom by reversing the procedure for this extension, the jib is moved around the jib axis in the opposite direction to the above-mentioned extension process. When the jig is rotated, the rotation angle is regulated to a constant by the preset mechanism, and the jig is placed in the predetermined storage position. , storage method.