JPH0139486B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a mechanism for clamping two molds, such as an upper mold and a lower mold, constituting a mold into a state in which they are opposed and combined.

[Conventional technology]

An example of a conventional tightening mechanism of this type is the one described in Japanese Patent Application Laid-Open No. 58-31707. That is, this tightening mechanism attaches a hook to a bolt provided on the upper mold and extending in the longitudinal direction of the upper mold.
This is a mechanism in which the hook is actuated by advancing and retracting the bolt to bring the protruding pieces (vertical ribs) of the upper frame and lower frame relatively closer together, thereby tightening the upper frame and the lower frame.

[Problem that the invention seeks to solve]

However, in the case of such a conventional tightening mechanism, as described in the above-mentioned publication, most of the weight of the part is concentrated in the upper mold, so when performing centrifugal casting using this mold, There is a problem that the balance is lost and the formwork does not rotate smoothly.

In addition, since the bolts for tightening are pulled with great force, the upper mold may deform, causing misalignment between the upper and lower molds, or reducing the length of the upper mold.
Furthermore, since the bolt elongates and the position of the hook changes in the longitudinal direction of the bolt, it is necessary to frequently adjust the position of each hook.

This invention was made by focusing on the problems of the prior art, and aims to ensure smooth rotation of the formwork, ensure strength and accuracy of the tightening position, and strength of the formwork, and improve the tightening operation. It is intended to make it easier.

[Means to solve the problem]

The present invention relates to a formwork tightening mechanism that tightens two molds forming a formwork while facing each other, and a formwork tightening mechanism that tightens two molds forming a formwork while facing each other. , first and second protruding pieces provided on the mold and facing each other;
A pin that penetrates from the protruding piece to the second protruding piece and has a head at one end of the first protruding side and has an engaging recess formed in the side near the end of the second protruding side;
a seat formed on the first protruding piece on which the head of the pin is seated; a claw member that contacts the inner surface to prevent the pin from coming off; the pin is configured such that the distance between the head and the engaging recess is adjustable by screwing the pin body and the head together; The structure is based on what was done.

[Effect]

With the first and second protruding pieces facing each other, the first
Pass a pin through both protruding pieces from one side of the protrusion from the tip, and insert the pin into one side of the second protrusion so that the head is seated on the seat of the first protrusion and the tip protrudes sufficiently so that both protrusion pieces can be connected. Make them stick out until they are as close as possible. Then, the tip of the claw member engages with the engagement recess of the pin to prevent the pin from coming off, and the head of the pin is seated as described above and both protruding pieces are maintained as close as possible. Ru. This state is the tightened state of the formwork.
When the tip of the claw member is removed from the engagement recess of the pin, the pin becomes free and the tightened state of the formwork is released. Further, the head of the pin moves in the axial direction of the pin main body by being rotated, and changes the distance from the engagement recess to change the tightening state of the two types.

〔Example〕

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention shown in the drawings will be described in detail below. Reference numeral 1 denotes a mold, which has an elongated shape with a circular cross section, and is composed of a lower mold 2 and an upper mold 3, which face each other and have a semicircular cross section. Angle members are welded to opposing edges of the upper and lower molds 2 and 3 to form a first projecting piece 5 and a second projecting piece 4. The second protruding piece 4 is welded to the upper edge of the lower die 2, the first protruding piece 5 is welded to the lower edge of the upper die 3, and both protruding pieces 4 and 5 are oriented in the same direction. It stands out.

Both protruding pieces 4 and 5 have holes 4a passing through them.
5a is opened, and the upper surface of the first protrusion piece 5 has a hole 5a.
A cylindrical body 6 is welded concentrically with.

A pin 9 having a square cross section is attached to the cylindrical body 6 from above.
penetrates. This pin 9 is as shown in FIG.
A pin body 9A having a substantially regular square columnar cross section, and a cylindrical screw portion 31 connected to the head side of the pin body.
and a head 9B that can be screwed into this threaded portion. Therefore, the pin main body 9A and the head 9B are screwed together, and the effective length of the pin 9 can be adjusted. . In addition, the head 9 of the pin body 9A
The tip of B is chamfered. pin 9
The lower surface of the head 9B is configured to sit on a seat 6a formed on the upper end surface of the cylindrical body 6.
A groove 9b is formed around the lower part of the groove 9b, and the upper end of the coil spring 11 is wound around the groove 9b. The pin body 9A is screwed onto the head 9B from the peripheral surface side.
A fixing screw 20 is provided to fix the threaded portion 31 of. The lower end of the coil spring 11 is wound around a groove 6b formed on the circumferential surface of the cylindrical body 6, and the pin 9 is supported by the cylindrical body 6 by the coil spring 11 in the free state of the spring. At this time, the pin body 9A
The free length of the coil spring 11 is set in advance so that the tip of the coil spring 11 is located within the hole 5a of the first protruding piece 5.

The tip of the pin body 9A is connected to each hole 5 of both protruding pieces 5, 4.
a, 4a and protrudes below the second protruding piece 4. Near the tip of the pin body 9A, V-shaped grooves are formed on two opposite sides of the circumferential surface to form an engagement recess 12. This engagement recess 1
2 is formed from two inclined surfaces. 7th
As shown in the figure, the upper engaging surface 1 of the two surfaces
2A is a flat surface, and the lower engagement surface 12B is an R-shaped curved surface. The tip of the claw member 13 is engaged with the engagement recess 12 to prevent the pin 9 from coming off. The tip of the claw member 13 is connected to the R of the engagement surface 12B.
It is also formed in an R shape to match the shape.

A pair of claw members 13 are attached to a bracket 14 welded to the lower surface of the second projecting piece 4, and two bolts are attached to the bracket 14.
Due to the book pivot 15, each tip is connected to the pin body 9A.
They are individually pivoted in positions that sandwich them. The tips of the claw members 13 are configured to rotate between the illustrated position where they engage with the engagement recess 12 of the pin body 9A and the downward direction of the pivot shaft 15, and a plate is provided at the rear end of each claw member 13. Spring 1
One end of 6 is locked. The other end of the spring 16 is wound around the pivot shaft 15, and the claw member 13 is biased in such a direction that its rear end descends and its tip rises.
The tip of the claw member 13 has a shape corresponding to the shape of the engagement recess 12 of the pin 9, and in order to prevent the pin 9 from coming off, the engagement area of the tip of the claw member 13 with the engagement recess 12 is made large. There is. In particular, the engagement recess 1
2 is formed of two inclined planes, and the tip of the claw member 13 that engages with this engagement recess 12 is formed with a plane so as to be in surface contact with this engagement recess 12, and the pin 9 and the claw are This makes the engagement of the member 13 more reliable. The pin main body 9A is formed to have a square cross section, the engaging recesses 12 are formed on two opposite sides of the pin main body, and the claw members 13 are formed in a pair so as to sandwich the pin 9. As a result of increasing the total engagement area between the member 13 and the engagement recess 12, the engagement between the pin body 9A and the claw member 13 is further ensured. In addition, since the pin body 9A has a square cross section, the claw member 13 and the engagement recess 1
Positioning with 2 becomes easy.

Next, the operation of this embodiment will be explained.

First, the effective length of the pin 9 is determined by rotating the head 9B of the pin 9. For this purpose, the pin body 9A of the pin 9 is attached to the protruding pieces 4, 5 while the upper and lower molds 2, 3 are tightened by pressing the protruding pieces 4, 5 together.
The distal end of the claw member 13 is engaged with the engaging portion 12 of the pin main body 9A. At this time, the tip of the claw member 13 is engaged with the engaging portion 12 of the pin body 9A, and the protruding pieces 4 and 5 are in pressure contact with the head 9B.
Rotate. Then, the seat 6a of the cylindrical body 6 is brought into pressure contact with the lower surface of the head 9B, and the head 9B is brought into contact with the lower surface of the head 9B.
The fixing screw 20 B is tightened to fix the head 9B to the pin body 9A, and the length of the pin 9 is determined.

In this state, the protruding pieces 4 and 5 pass through the pin body 9A, and the claw member 13 is inserted into the engagement recess 12.
When the tip of the head 9B is engaged, the lower surface of the head 9B becomes the cylindrical body 6.
The positional relationship is such that the protruding pieces 4 and 5 are in pressure contact with the seat portion 6a. After the length of the pin 9 is determined in this way, it is not necessary to do this frequently.

Next, the tightening operation of the formwork 1 will be explained.

When the upper frame 3 is placed over the lower frame 2, the first protruding piece 5 overlaps the second protruding piece 4. At this time, since there is a raw material such as concrete for molding in the formwork 1, the protruding pieces 4 and 5 are not pressed together by the weight of the upper frame 3 alone. Therefore, the pin 9 whose tip has been pushed up by the coil spring 11 to the position shown by the chain line in FIG. 3 is pushed down to the position shown by the solid line in the figure by pushing the upper surface of the head 9B.

When pin 9 is pushed down, coil spring 11
is compressed and the tip of the pin body 9A becomes the first protruding piece 5
The head 9B protrudes downward from the hole 5a, and the lower surface of the head 9B is seated on the seat 6a of the cylindrical body 6. Then, when the pin 9 is continued to be pushed down, the pushing down force is applied to the head 9B.
The force is transmitted to the first protruding piece 5 via the cylindrical body 6, and as a result, the entire upper mold 3 is pushed down. Therefore, the first protruding piece 5 is crimped onto the second protruding piece 4, but if you look at the movement of the pin 9 with respect to the second protruding piece 4 during this process, the tip of the pin body 9A will be attached to the hole 4a.
, and protrudes below the second protruding piece 4 . Then, due to the bias of the spring 16, the tip of the descending pin 9 hits the upper side of the tip of the claw member 13 at the position indicated by the chain line in FIG. 3, and the tip of the claw member 13 is pushed down. The claw member 13 pivots against the bias of the spring 16, and in this state, the vicinity of the tip of the pin body 9A slides down on the tip of the claw member 13. and the first protruding piece 5
At the same time as the pin 9 is pressed against the second projecting piece 4, the pin 9 reaches the bottom dead center, and at the same time, the tip of the claw member 13 engages with the engagement recess 12 of the pin body 9A.

The pin 9 is pressed down using a device such as a shaky vise. Using an air cylinder device instead of the screw rod of the Shiyako vise, the upper surface of the head 9B and the bracket 1
When the bracket 14 and the head 9B are brought close to each other by applying the supporting part of the flexure vise and the tip of the piston rod of the air cylinder to the lower surface of the pin 9, the pin 9 can be easily pushed down as described above.

After the form 1 is tightened by pressing the first protruding piece 5 against the second protruding piece 4, the form 1 is rotated at high speed to perform centrifugal casting of concrete or the like. At this time, even if an opening force is applied to the upper die 3 and the lower die 2 due to centrifugal force, the tip of the claw member 13 is engaged with the engagement recess 12 of the pin body 9A, so that the pin 9 cannot be pulled. The pressed state of the protruding pieces 4 and 5 is maintained by the tensile stress. Further, when a centrifugal force acts on the claw member 13, since the rear end of the claw member 13 is elongated, a force is applied that causes the claw member 13 to pivot in the direction of the position shown by the chain line in FIG. Therefore, since the centrifugal force generates a force in the direction in which the tip of the claw member 13 bites into the engagement recess 12, the function of the claw member 13 to prevent the pin 9 from coming off is not impaired.

Next, demolding of the molded product using the formwork 1 will be explained. In this case, the claw member 13 is pivoted in a direction in which its rear end rises against the bias of the spring 16. As a result, the tip of the claw member 13 is attached to the pin body 9A.
from the engagement recess 12. This pivoting of the claw member 13 is performed, for example, by moving the formwork 1 to the demolding position using a crane or the like. This movement is formwork 1
All you have to do is lift it up, move it, and lower it to the demolding position. If a protrusion or the like is provided at a position corresponding to the rear end of the claw member 13 at the position where the formwork 1 is lowered, the rear end of the claw member 13 will come into contact with this protrusion, and the rear end of the claw member 3 will be relatively lifted. Since the engagement surface 12B between the claw member 13 and the pin body 9A is formed in an R shape, the entire claw member 13 pivots as described above.

When the claw member 13 is thus separated from the engagement recess 12, the pin 9 is raised to its original position by the biasing force of the coil spring 11, that is, to the position where the lower end is indicated by the chain line in FIG. This position is a position where the lower end of the pin body 9A does not protrude below the first protrusion piece 5, and therefore the pin 9 does not interfere with demolding of the molded product or maintenance of the formwork 1. Then, raw materials such as concrete are again put into the formwork 1 and the next molding operation is performed.

In this embodiment, when the pin 9 is lowered, the coil spring 11 is bent and the lower surface of the head 9B is seated on the seat 6a of the cylindrical body 6, and then the first protruding piece 5 is connected to the second protruding piece 4. As explained in the press-contact procedure, if the resistance to the downward movement of the first protruding piece 5 and the spring constant of the coil spring 11 are different,
After the first protruding piece 5 is pressed against the second protruding piece 4, the coil spring 11 is bent, and both operations proceed simultaneously. Further, the head 9B of the pin 9 has a hexagonal shape in the illustrated case, but the shape may be circular or any other shape as long as the head 9B can be rotated. Further, the shape of the engagement recess 12 and the shape of the tip of the claw member 13 may be other shapes as long as they can be engaged and disengaged as described above and are in contact with each other. Furthermore, in the above embodiment, the first protruding piece 5
Although the cylindrical body 6 provided integrally with the pin 9 can be seated on the head 9B of the pin 9, other shapes and structures may be used.
Of course, depending on the weight balance with the bracket 14, claw member 13, etc. provided on the side, it is also possible to have a configuration in which the cylindrical body 6 is not provided. In the above embodiment, two engagement recesses 12 and two claw members 13 are provided, but one may be sufficient depending on the required tightening force.

Further, in the above embodiment, the cross section of the pin 9 is formed into a substantially regular square shape, but the cross section is not limited to this, and may be formed into other shapes such as a spherical shape, an elliptical shape, a rectangular shape, etc.

Furthermore, in the embodiment described above, the inclined surface 12B forming the engagement recess 12 is formed in an R shape, but it can also be formed in a planar shape.

[Explanation of the idea]

As explained above, according to the present invention, the formwork can be tightened simply by pushing the pin in, seating its head on one side of the first protrusion, and engaging the claw member in the engagement recess of the pin. I can do it. In particular, since the head of the pin is rotatably adjustable and the effective length of the pin is changed, it is possible to uniformly set the strength of tightening between the upper and lower molds in the longitudinal direction. Further, the first protruding piece supports a pin,
This pin passes through both protruding pieces, and the claw member is supported by the second protruding piece, so the weight between the upper and lower molds is relatively balanced.
Even when this mold is used for centrifugal casting, it has the effect of ensuring smooth rotation of the mold. Furthermore, according to this invention, the bolts extending in the longitudinal direction of the formwork are not pulled with great force for tightening, which causes the upper mold to deform and misalignment between the upper and lower molds. In addition, the length of the upper die will not be reduced, and there is no fear that the bolt will elongate and the position of the hook will change in the longitudinal direction of the bolt. This also has the effect of making maintenance and management of the formwork easier.

[Brief explanation of drawings]

Figure 1 is a front view of the formwork, Figure 2 is the − of Figure 1.
3 is a cross-sectional view of essential parts showing an embodiment of the present invention, FIG. 4 is a plan view of the pin and the cylindrical body, and FIG. 5 is a side view showing the state in which the pin body and the claw member are engaged. Figure 6 is a sectional view taken along the - line in Figure 4, and Figure 7 is
The figure is a partial side sectional view of the pin. 1...Formwork, 2...Bottom frame, 3...Top frame, 4...
Second protruding piece, 5... First protruding piece, 6... Cylindrical body, 6a... Seat, 9... Pin, 9A... Pin body, 9B... Head, 11... Coil spring, 12 …
...Engaging recess, 13...Claw member, 14...Bracket, 15...Pivot, 16...Spring.

Claims (1)

[Scope of Claims] 1. A formwork tightening mechanism for tightening two molds forming a formwork in a state where they face each other, comprising first and second protrusions provided on the molds and facing each other. a piece, penetrating from the first protruding piece to the second protruding piece;
A pin having a head at one end of the first protrusion and an engaging recess formed in the side near the end of the second protrusion, and a pin having a head formed on the first protrusion piece. a claw member that is supported by a seat to be seated and a second projecting piece, and whose tip engages the engagement recess in a rotational manner due to the protrusion of the pin, contacts the inner surface of the engagement recess, and prevents the pin from coming off; A formwork tightening mechanism, characterized in that the pin is configured such that the pin main body and the head are screwed together so that the distance between the head and the engagement recess can be adjusted. 2. The formwork tightening mechanism according to claim 1, wherein the pin has a quadrilateral cross section, and the engaging recess is formed on one side or two opposing sides thereof.