JP3255826B2 - Lightweight cellular concrete cutting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight aerated concrete cutting device, and more particularly, it can reduce the load applied to a push-down arm when a split support plate is raised and lowered, and can improve the durability of a cam type lifting mechanism. The present invention relates to a lightweight cellular concrete cutting device.

[0002]

2. Description of the Related Art As a kind of wall plate of a building, a plate material made of lightweight cellular concrete having a light weight and good fire resistance is known. This plate material is manufactured by cutting a semi-dry and thick block-like lightweight cellular concrete into a predetermined width by a lightweight cellular concrete cutting device having a piano wire. 2. Description of the Related Art As a conventional lightweight cellular concrete cutting device, there is known, for example, the one disclosed in the specification of FIG.

In this apparatus, a divided support plate for downwardly supporting a semi-dry, horizontally long lightweight cellular concrete is fixed to the tip of a rod of a support cylinder composed of a number of air cylinders arranged in the machine length direction. A gate-shaped movable trolley that can move in the machine length direction along the rail is disposed above, and the movable trolley has a cutting frame body having a lower frame that can move between the lowered divided support plate and the lightweight cellular concrete. It is attached in a suspended state. A large number of piano wires for cutting lightweight cellular concrete are attached to the cutting frame at predetermined intervals.

[0004] In this conventional lightweight cellular concrete cutting apparatus, when the lower frame of the cutting frame approaches each support cylinder as the movable trolley moves in the machine length direction, the switching valve is automatically operated by a control device. , Sequentially lower the rod of the support cylinder to avoid collision, after passing,
The lightweight cellular concrete is supported by immediately switching the switching valve and projecting the rod. While performing this operation sequentially and continuously for each support cylinder,
Lightweight cellular concrete is cut to a predetermined width by a piano wire.

[0005]

However, in the above-mentioned prior art lightweight cellular concrete cutting apparatus, since the supporting cylinders are air cylinders driven by air pressure having poor response, the respective supporting cylinders are not provided. At the time of approaching or passing the cutting frame, when the switching valve is operated to move the rod in and out to raise and lower the divided support plate, the responsiveness of raising and lowering the divided support plate is poor, and the moving carriage is not moved at a relatively low speed. As a result, a stable operation timing of the support cylinder in which the lower frame does not collide with the divided support plate cannot be obtained. As a result, there is a problem that productivity is reduced.

Accordingly, the inventor of the present application has proposed that when the cutting frame approaches each lifting structure by moving the movable bogie in the machine length direction, the cam type lifting mechanism is actuated to the descending side.
By rotating the push-down arm at a predetermined timing, together with the corresponding elevating rod, the divided support plate that has been urged upward by the spring is lowered, and during this descent, the lower frame of the cutting frame that moves together with the movable carriage, Pass through the gap between these lightweight cellular concrete and the split support plate, then
The upward movement of the cam type lifting mechanism causes the push-down arm to rotate in the opposite direction, and the corresponding lifting rod and the divided support plate are sequentially raised to the original support position, thereby sequentially supporting the divided support. Improves the responsiveness of lifting and lowering of the plate, thereby obtaining a stable operation timing of the lifting structure in which the lower frame does not collide with the divided support plate even if the mobile trolley is moved at a relatively high speed and high-speed operation is performed. A prototype of a lightweight aerated concrete cutting device that has the effect of improving productivity was obtained.

In such a lightweight cellular concrete cutting apparatus, when the divided support plate is lowered to allow the lower frame of the cutting frame to pass through the gap between the lightweight cellular concrete and the divided support plate, the divided support plate is divided. A large compressive force is applied to the spring that is urging the plate upward. Since the expansion and contraction of the spring is frequently performed during the operation of the apparatus, there is a possibility that the spring may be broken due to fatigue. In addition, the compression force of the spring exerts a large load on the push-down arm for lifting and lowering the split support plate and the lift rod, so that it was expected that the durability of the push-down arm would be reduced.

[0008] Further, in this lightweight cellular concrete cutting device, when the movable cart is pulled back to the original position after the lightweight cellular concrete is cut, each cam type lifting / lowering mechanism is structurally similar to that at the time of the forward cutting. In this case, it is necessary to sequentially return the divided support plates while moving up and down, thereby increasing the number of times the load is applied to the push-down arm.

The present invention has been made in view of the above circumstances, and provides a lightweight cellular concrete cutting device capable of reducing the load applied to the push-down arm when the divided support plate is raised and lowered, and thereby improving the durability of the cam type lifting mechanism. The purpose is to do.

[0010]

According to the present invention, there is provided a semiconductor device comprising:
The described lightweight cellular concrete cutting device is provided in parallel with the machine length direction, a number of lifting structures having lifting rods attached with a divided supporting plate of lightweight cellular concrete in a semi-dry and block state, and a guide rail. A movable trolley that can move in the machine length direction along with the movable trolley, a large number of the lightweight cellular concrete cut materials attached to the movable trolley at predetermined intervals, and the lowered divided support plate and the lightweight cellular concrete are lowered. The cutting frame having a lower frame that can pass through the gap, and the movable trolley side and the respective lifting structure side are arranged, and the lifting arm is rotated at a predetermined timing to raise and lower the lifting rod itself. A lightweight cellular concrete cutting device comprising: a plurality of cam-type elevating mechanisms; It is configured to provide a granulation body.

According to a second aspect of the present invention, there is provided the lightweight cellular concrete cutting apparatus according to the first aspect, wherein the cam of the cam type lifting mechanism is moved between a set position and a retracted position by moving means. It is configured to be movable.

[0012]

In the lightweight aerated concrete cutting apparatus according to the first or second aspect, the movable bogie is moved in the machine length direction,
When the cutting frame approaches each lifting structure, the downward movement of the cam-type lifting mechanism rotates the push-down arm, pushes down the corresponding lifting rod, and lowers the divided support plate. During this lowering, the lower frame of the cutting frame moving together with the moving carriage passes through the gap between these lightweight cellular concrete and the split support plate, and then is actuated by the upward movement of the cam type lifting mechanism. Since the lifting rod is pushed up and the divided support plate is sequentially moved up to the original support position, the responsiveness of raising and lowering the divided support plate is improved, thereby moving the movable trolley at a relatively high speed to operate at high speed. , The stable operation timing of the lifting / lowering structure in which the lower frame does not collide with the divided support plate can be obtained, so that productivity can be improved.

When the divided support plate is lowered to allow the lower frame of the cutting frame to pass through the gap between the lightweight cellular concrete and the divided support plate, the load applied to the push-down arm increases the height of the divided support plate. From time to descent, the counterweight structure stabilizes at a relatively small value. Thus, the load applied to the push-down arm when the split support plate is raised and lowered can be reduced, and the durability of the push-down arm and the durability of the cam type lift mechanism can be improved.

According to the second aspect of the present invention, when the movable cart is pulled back to the original position after cutting the lightweight cellular concrete, the moving means moves the cam of the cam type lifting mechanism from the set position to the retracted position. Therefore, the load on the push-down arm when the movable cart is pulled back can be eliminated.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will now be described with reference to the accompanying drawings to provide an understanding of the present invention. For convenience of explanation, in the drawings, the machine length direction is defined as an X direction, the machine short direction is defined as a Y direction, and the height direction is defined as a Z direction. Here, FIG. 1 is an enlarged front view of the lightweight aerated concrete cutting device according to one embodiment of the present invention on the moving cart side, FIG. 2 is an overall side view showing the same use state, and FIG. 3 is an enlarged side view of the moving cutting device. FIG. 4 is an enlarged front view of the essential part, and FIG. 5 is S5-S5 of FIG.
FIG. 6 is an enlarged bottom view of the main part of the moving means of the cam type elevating mechanism, and FIG. 7 is an enlarged side view of the main part of another moving means of the cam type elevating mechanism.

As shown in FIG. 2, the lightweight cellular concrete cutting apparatus 10 according to one embodiment of the present invention includes a placing apparatus 12 extending in the X direction on which a semi-dry, lightweight cellular concrete 11 is placed. A guide rail 13 disposed on both sides of the mounting device 12 and extending in the X direction; and a movable lightweight concrete 1 movable along the guide rail 13.
1 is provided with a moving cutting device 14 for cutting 1 into a number of concrete plates.

As shown in FIG. 1 and FIG.
A plurality of lifting structures 16 having lifting rods 15 arranged in two rows in the Y direction (machine short direction) are arranged along the X direction (machine length direction) on the base 12a. At the upper ends of the paired lifting rods 15, divided support plates 17 for dividing and supporting the lightweight cellular concrete 11 are horizontally laid. Has a hanging part 17a integrally formed. Each elevating rod 15 is attached to the outside of the hanging part 17a of the divided support plate 17, and a roller 18 whose axis is oriented in the X direction is provided at the lower end of the elevating rod 15. In addition, a support plate 21 having an inverted J-shape as viewed from the front is provided upright on both lower sides of each lifting structure 16.
The bearing 21a of the elevating rod 15 is attached to the tip of the rod with its axis oriented in the Z direction. In addition, the support plate 21
It is T-shaped in cross section.

At the center of the lower part of each elevating structure 16, a weight storage box 100 having a top surface opened and elongated in the Y direction is provided.
It is mounted in a state of standing on the base 12a,
In this weight storage box 100, counter weight 1
01 is stored in a vertically movable manner. An equalizer 102 is attached to the upper surface of the counterweight 101, and sprockets 103 are provided on the flanges 101a on both sides of the weight storage box 100. One end of the chain 104 is fixed to the lower end of each hanging part 17a of the divided support plate 17, respectively. The chain 104 is once drawn around each sprocket 103 and descends into the weight storage box 100, and the other end is attached to both ends of the equalizer 102. As the divided support plate 17 moves up and down, via the chain 104 folded back by the sprocket 103,
Since the counterweight 101 moves up and down in the weight storage box 100, the divided support plate 17 can be moved up and down with a relatively small force. These components 100 to 104 constitute a counterweight structure 50.

A base portion of a shaft mounting plate 105 protruding outward is fixed to one of the bearings 21a, and a push-down arm 31 whose upper and lower ends are bent vertically via a pin 106 at the front end thereof. It is pivotally mounted on the shaft. A guide roller 31a is axially mounted on the upper end of the push-down arm 31, and the guide roller 31a is mounted in a guide hole 17b formed in the center of the divided support plate 17 so as to be rotatable in the horizontal direction. Have been.

The mounting device 12 is provided with a number of cam-type elevating mechanisms 23 for sequentially lowering the elevating rod 15 as the movable cutting device 14 moves. First, the moving cutting device 14 will be described in detail with reference to FIG. As shown in FIG. 3, the movable cutting device 14 has a movable carriage 24 that slides on the guide rail 13 via a slider 24a. A portal frame 25 is mounted on the movable trolley 24, and a piano wire cassette frame 27, which is an example of a cutting frame, is detachably mounted inside the portal frame 25. The piano wire cassette frame 27 has a large number of piano wires 26 which are an example of a cut material extending in the Z direction.
It is stretched at a constant pitch in the direction. The piano wire cassette frame 27 allows the rods of the air cylinders 28 arranged in pairs at the upper and lower portions of the gate-shaped frame 25 to be taken in and out.
The piano wire cassette frame 27 is connected to the portal frame 25 by fitting a tapered stopper 29 fixed to the tip of the rod into a tapered hole 30 formed at any one of the four corners of the piano wire cassette frame 27. The piano wire cassette frame 27 can be firmly hooked or removed so that it can be replaced with another piano wire cassette frame (a taper groove (not shown) for vertical positioning is provided at another corner of the piano wire cassette frame 27). Is formed).

Next, with reference to FIGS. 4 to 6, it is arranged between the moving carriage 24 and the respective lifting / lowering structures 16,
At normal times, the lifting rods 15 are firmly supported so that the lightweight cellular concrete 11 can be firmly supported downward, and when the lifting rods 15 are raised and lowered by the cam type lifting mechanism 23, the lifting rods 15 are opened to a state where they can be raised and lowered. The wedge stopper mechanism 37 will be described. As shown in FIGS. 4 and 5, the wedge stopper mechanism 37 includes a wedge base plate 109 which is disposed on both ends of the base 12 a of the mounting device 12 and is movable in the Y direction by a Y rail 107 and a slider 108. Have. A rod hole 110 is formed on the base side of the wedge base plate 109 from the center, and an outer corner of the wedge base plate 109 is tapered at the base of the base. A wedge member 111 for the roller 18 is provided. An arc-shaped notch 12b communicating with the rod hole 110 when the wedge base plate 109 is pushed into the base 12a is provided at a position directly below the lifting rod 15 of the base 12a. As many as 16 are provided. A cam floor 112 is mounted on the center of the front end of the wedge base plate 109 via a pin 113.

Each support plate 21 is placed on the base 12a.
A spring case 114 having an outer surface opened is fixed therebetween, and a spring 115 that constantly pushes the wedge base plate 109 outward in a biased state is accommodated therein. Needless to say, the Y rail 107 and the slider 108 are provided with a stopper structure (not shown) for preventing the wedge base plate 109 from protruding outward. As shown in FIGS. 4 and 6, mounting members 116 long in the X direction are fixed to inner surfaces of both ends in the Y direction of the movable cart 24, and a cam floor 112 is provided at the center of the lower surface of each mounting member 116. A hydraulic cylinder 118, which is an example of a moving unit that moves the cam 117 that is in contact with the cylinder 117, is attached. The cam 117 is a thick plate that is long in the X direction and has both ends bent outward. Mounting member 11
6, a bearing 120 and a guide rod 121 loosely inserted and extending in the Y direction are disposed around the hydraulic cylinder 118.
1 are fixed to the inner surfaces of both ends of the cam 117.

When the rod 118a of the hydraulic cylinder 118 is made to protrude, the cam 117 at the retracted position is guided by the guide rod 121, and is moved to the set position inside the elevating structure 16. As a result, when the movable cart 24 approaches from the X direction, the cam floor 112
After abutment with the cam floor 17, the wedge base plate 109 is pushed into the lift structure 16 together with the cam floor 112. In this way, the wedge member 111 is disengaged from the roller 18 of the lifting rod 15, the rod hole 110 and the notch 12b are in communication, and the lifting rod 15 can be lowered. When the moving carriage 24 passes and the cam floor 112 is disengaged from the cam 117, the wedge base plate 109 is pushed outward by the urging force of the spring 115, and the wedge member 111 is placed under the roller 18 of the lifting rod 15 at the raised position. Is inserted. Next, the cam type elevating mechanism 23 will be described in detail with reference to FIGS.

As shown in FIGS.
A hydraulic cylinder 123, which is an example of a moving unit that raises and lowers a cam 122 extending in the X direction, is attached to the center of the inner side surface of the lifting structure 16 of FIG. The cam 122 is
The push-down arm 31 is a plate member shorter than the cam 117 of the wedge stopper mechanism 37 and having upper portions at both ends inclined and cut.
Can be brought into contact with the cam floor 126 which is mounted on the lower end surface of the cam shaft. On both sides of the hydraulic cylinder 123, a bearing 124 and a guide rod 125 extending in the Z direction are arranged. When the rod 123a of the hydraulic cylinder 123 is protruded, the cam 122 located at the retracted position is guided by the guide rod 125 and moved to the upper set position. In this state, when the moving carriage 24 approaches from the X direction, the cam 122 contacts the cam floor 126 to push it up, and the push-down arm 31 pushes the pin 10 down.
1 is rotated vertically in the direction of the arrow in FIG. 1 to push down the divided support plate 17 together with the lifting rod 15. Thus, as shown in FIG. 1, a gap is formed between the lower surface of the lightweight cellular concrete 11 and the upper surface of the divided support plate 17, and while the gap is formed, the lower frame 2 of the piano wire cassette frame 27 is formed.
7a passes. In FIG. 3, reference numerals 43 to 46 denote attachment members, reference numeral 47 denotes a piano wire holding member, and reference numeral 127 in FIG. 1 denotes a dust pan disposed below between adjacent divided support plates 17.

Next, the operation of the lightweight cellular concrete cutting apparatus 10 according to one embodiment of the present invention will be described. Figures 1 and 4
As shown in FIG. 7, when the moving carriage 24 moves in the X direction along the guide rails 13 and the piano wire cassette frame 27 approaches each lifting structure 16, first, the hydraulic cylinder 118 of the wedging mechanism 37 and the cam type lifting The cams 117 and 122 are moved to the set position by the hydraulic cylinder 123 of the mechanism 23. First, the cam floor 112 rides on the relatively long cam 117, and the wedge base plate 109 is pushed into the inside of the elevating structure 16, whereby the roller 18 is disengaged from the wedge member 111, and directly below the elevating rod 15. And a rod hole 110 communicating with the notch 12b.

Slightly after that, the cam 122 abuts the cam floor 126 and continuously pushes it upward.
Since the push-down arm 31 is rotated about the pin 106, the guide roller 31a at the upper end of the push-down arm 31 is used.
, The divided support plate 17 and the lifting rod 15 are pushed down integrally. At this time, the counterweight 101 is connected via the sprocket 103 and the chain 104.
Is lifted with a weight balance, whereby each lifting rod 15 is inserted into the opened rod hole 110 and notch 12b. In this way, a gap is formed between the lightweight cellular concrete 11 and the divided support plate 17, and while the gap is formed, the lower frame 27a of the piano wire cassette frame 27 passes and is partially Is cut off.

Next, the cam 122 is disengaged from the cam floor 126, and the push-down arm 31 rotates in the opposite direction about the pin 106, whereby the divided support plate 17 is pulled up while lowering the counterweight 101. As a result, the lifting rod 15 is pulled out from the notch 12b or the rod hole 110, and then the cam floor 112 is disengaged from the cam 117, and the wedge base plate 109 is pushed back to the original position by the urging force of the spring 115. By repeating the above-described concrete cutting operation in each elevating structure 16 sequentially, the lightweight cellular concrete 11
It is completely cut by a large number of piano wires 26 over its entire length to form a predetermined number of plate members. After that, the cams 117 and 122 are returned to the retreat position by the hydraulic cylinders 118 and 123, and then the movable cart 24 is returned to the cutting start position at a stretch. Since the cams 117 and 122 are in the retracted positions, when the movable carriage 24 is pulled back, the pushing-down load of the divided support plate 17 is not applied to the pushing-down arms 31 and the wedge base plate 109 is not pushed inward. .

As described above, since the cam type elevating mechanism 23 having good response is adopted as the elevating structure 16 of the divided support plate 17, the elevating and lowering of the divided support plate 17 becomes accurate and agile.
As a result, even if the movable carriage 24 is moved at a relatively high speed and the high-speed operation is performed, the piano wire cassette frame 27
The lower frame 27a does not collide, and stable operation timing of the lifting / lowering structure 16 can be obtained, so that productivity can be improved. In addition, since the counterweight structure 50 is provided in the cam type lifting mechanism 23 of the split support plate 17, the load applied to the push-down arm 31 when the split support plate 17 is raised and lowered is reduced, and the durability of the push-down arm 31 is thereby reduced. As a result, the durability of the cam type lifting mechanism 23 can be improved.

Further, the cam 122 is retracted by the hydraulic cylinder 123 when the movable carriage 24 is pulled back.
Load can be eliminated.

Although the present invention has been described above, the present invention is not limited to these embodiments, and any changes in the design or the like without departing from the scope of the present invention are included in the present invention. For example, the structure of the cam-type elevating mechanism is not limited to that of the embodiment, and any structure may be used as long as it can elevate the adjacent divided support plate with the movement of the cutting frame. The lifting structure is not limited to the embodiment, but may be any structure as long as the lifting rod to which the divided support plate is attached can be raised and lowered by a cam-type lifting mechanism.

Further, in the embodiment, the moving carriage is shown as moving along guide rails arranged on both sides of the apparatus. However, the present invention is not limited to this. It may be of a suspended type that moves along a guide rail disposed above a lightweight cellular concrete placing device. In the embodiment, the piano wire is shown as the cutting material of the lightweight cellular concrete. However, the invention is not limited to this, and any material may be used as long as it can cut the lightweight cellular concrete. Also, the method of attaching the cutting material to the cutting frame body is not vertical stretching as in the embodiment,
It may be horizontal. Subsequently, in the embodiment, the support by the divided support plate of the lightweight cellular concrete at the normal time is made solid by the openable wedge mechanism,
The structure is not limited to this, and the structure without using the wedge stopper mechanism may be adopted. Further, instead of the wedge stopper mechanism, another lifting rod supporting structure capable of switching between firm support and support release may be employed.

[0032]

As described above, the lightweight cellular concrete cutting device according to the first and second aspects employs a responsive cam-type elevating mechanism as the elevating operation mechanism of the divided support plate, so that the divided support plate can be moved up and down. Accuracy and agility make it possible to obtain stable operation timing of the lifting structure without collision of the lower frame with the split support plate even when moving the mobile trolley at relatively high speed and operating at high speed. Thus, productivity can be improved. In addition, since the counterweight structure is deployed on the cam type lifting mechanism of the split support plate,
The load applied to the push-down arm when the divided support plate moves up and down is reduced, thereby improving the durability of the push-down arm and the durability of the cam-type elevating mechanism.

In particular, in the lightweight cellular concrete cutting apparatus according to the second aspect, when the movable carriage is pulled back, the cam of the cam type lifting mechanism is retracted by the moving means. Can be eliminated.

[Brief description of the drawings]

FIG. 1 is an enlarged front view of a lightweight aerated concrete cutting device according to one embodiment of the present invention, on a moving cart side.

FIG. 2 is an overall side view showing the same use state.

FIG. 3 is an enlarged side view of the moving cutting device.

FIG. 4 is an enlarged front view of the main part.

FIG. 5 is an enlarged sectional view of S5-S5 in FIG. 1;

FIG. 6 is an enlarged bottom view of a main part of a moving unit of the cam type lifting mechanism.

FIG. 7 is an enlarged side view of a main part of another moving means of the cam type elevating mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Lightweight cellular concrete cutting device 11 Lightweight cellular concrete 12 Mounting device 12a Base 12b Notch 13 Guide rail 14 Moving cutting device 15 Elevating rod 16 Elevating structure 17 Split support plate 17a Hanging portion 17b Guide hole 18 Roller 21 Support plate 21a Bearing 23 Cam type lifting mechanism 24 Moving carriage 24a Slider 25 Gate frame 26 Piano wire 27 Piano wire cassette frame 27a Lower frame 28 Air cylinder 29 Stopper 30 Tapered hole 31 Push-down arm 31a Guide roller 37 Wedge mechanism 43 Mounting member 44 Mounting member 45 mounting member 46 mounting member 47 piano wire holding member 50 counterweight structure 100 weight storage box 101 counterweight 101a flange 102 equalizer 103 sp Ket 104 Chain 105 Shaft mounting plate 106 Pin 107 Y rail 108 Slider 109 Wedge base plate 110 Rod hole 111 Wedge member 112 Cam floor 113 Pin 114 Spring case 115 Spring 116 Mounting member 117 Cam 118 Hydraulic cylinder 118a Rod 120 Bearing 121 Guide rod 122 Cam 123 Hydraulic cylinder 123a Rod 124 Bearing 125 Guide rod 126 Cam floor 127 Dust pan

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshiki Yagi 14-10 Itanume-cho, Seya-ku, Yokohama-shi, Kanagawa Prefecture Within the Housing and Construction Materials Division, Sumitomo Metal Mining Co., Ltd. (72) Inventor Hidetaka Komichi Seya-ku, Yokohama-shi, Kanagawa 14-10 Gokanumecho Sumitomo Metal Mining Co., Ltd. Housing and Building Materials Division (56) References JP-A-8-48582 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B28B 11/00-11/22 C04B 38/00

Claims (2)

(57) [Claims] 1. A number of lifting structures each having a lifting rod to which a divided support plate of lightweight cellular concrete, which is arranged in a machine-length direction and is semi-dry and in a block state, is attached.
A movable trolley movable in the machine length direction along the guide rail, and a plurality of light-weight cellular concrete cut materials attached to the movable trolley at predetermined intervals, and the lowered divided support plate and the lightweight A cutting frame having a lower frame that can pass through a gap with the cellular concrete, and a cutting frame disposed between the movable trolley and the respective lifting / lowering structures, and rotating a pressing-down arm at a predetermined timing to move the lifting / lowering itself. A lightweight cellular concrete cutting device comprising: a plurality of cam-type lifting / lowering mechanisms for raising / lowering a rod, wherein the cam-type lifting / lowering mechanism is provided with a counterweight structure. 2. The lightweight cellular concrete cutting device according to claim 1, wherein the cam of the cam type lifting mechanism is movable between a set position and a retracted position by a moving means.