JPH0441194A - Holding device and method using elastic tube - Google Patents

Abstract

PURPOSE:To surely hold the body to be held having dispersions in the shape and size, by discharging the fluid inside the sealed space formed between a elastic tube and the outer cylinder provided at the outside thereof, and forcibly enlarging the inner diameter of the elastic tube. CONSTITUTION:The inner diameter of an elastic tube 2 having the inner diameter that the body to be held can not be passed through in the state of tension being not applied is forcibly enlarged by discharging the fluid inside the sealed space 4 formed between the elastic tube 2 and an outer cylinder 1 provided at the outside thereof. After arranging the body to be held inside the elastic tube 2 whose inner diameter is enlarged, the inner diameter of the elastic tube 2 is reduced with the fluid being fed into the sealed space 4 and the body to be held is held.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method and apparatus for gripping solid objects, which can be used in manufacturing plants and the like. More specifically, the present invention includes:
In manufacturing factories, etc., when the shape of the object to be grasped is cylindrical, elliptical, cylindrical, elliptical, or similar, and when grasping it, part or all of the outer circumference of the object is The present invention relates to a gripping method and device suitable for cases where it is necessary to cover objects, and capable of reliably gripping an object even when there is some variation in the size of the object.

(Prior art and its problems) Gripping an object having a cylindrical, elliptical, cylindrical, elliptical, or similar shape, and part or all of the outer periphery of the object. If you need to cover
Conventionally, this has been done by using a holder that is divided vertically into two cylinders, for example, and whose internal space matches the shape of the object when the left and right sides are brought into close contact with each other.

However, if there are variations in the shape and size of the object to be grasped,
In the case of a larger object to be grasped, the holder cannot be completely closed, resulting in an incomplete seal, and in the case of a smaller object to be grasped, the object to be grasped does not come into close contact with the holder, resulting in a weaker gripping force.

There is also a method of gripping an object by forcibly feeding air into a rubber tube whose inner diameter is sufficiently larger than the outer diameter of the object.

However, in this device, when air is introduced into the rubber tube, wrinkles occur in the rubber, resulting in incomplete sealing of the rubber tube.

For example, in order to apply a liquid to the inside of a cylindrical object having a tube extending in the axial direction only inside the object, the object is gripped by a gripping device, and a liquid tank is connected to the lower end of the object. Then, the liquid is forced upward from the liquid tank into the interior of the object to be grasped, and the liquid is applied only to the inside of the object to be grasped. In such a case, if a conventional gripping device using a rubber tube is used, wrinkles will occur in the rubber tube as described above, and the liquid forced upward will pass through the wrinkles.
It flows upward between the grasped object and the rubber tube,
Liquid adheres to the outside of the object to be grasped, making it impossible to achieve the purpose.

(Problem to be Solved by the Invention) Therefore, the problem to be solved by the present invention is that it is difficult to reliably grip an object when there is some variation in shape and size, which the prior art has. Furthermore, there is a problem in that the sealing between the object to be gripped and the gripping device is insufficient.

(Means for Solving the Problems) According to the present invention, in order to solve the problems as described above, a pipe-shaped outer body having an inner diameter through which an object to be grasped can easily pass and having sufficient strength is provided. a cylinder; and an elastic tube having an inner diameter that does not allow the object to be gripped to pass through in a state where no tension is applied, both ends of which are sealingly connected to the outer cylinder, and forming a sealed space between the cylinder and the inner wall of the outer cylinder. A gripping device using an elastic tube is provided, comprising: a discharge means for discharging fluid from the sealed space; and a supply means for supplying fluid to the sealed space.

Furthermore, according to the present invention, in order to solve the above-mentioned problem, the inner diameter of an elastic tube having an inner diameter through which an object to be grasped cannot pass when no tension is applied is set to the inner diameter of the elastic tube and the outer diameter provided on the outer side of the elastic tube. Forcibly expanding the sealed space by discharging the fluid in the sealed space formed between the tube; Placing the object to be grasped within the elastic tube whose inner diameter has been enlarged; A grasping method using an elastic tube is provided, the method comprising supplying a fluid to reduce the inner diameter of the elastic tube and grasping the object to be grasped.

According to the gripping device and method of the present invention, the object to be gripped has a cylindrical shape, an elliptical cylinder shape, a cylindrical shape, an elliptical cylinder shape, or
Items with a similar external shape can be held particularly well. Furthermore, the object to be grasped may be solid, for example, cylindrical, hollow and cylindrical with an open top and bottom, or have a tube extending in the axial direction.

However, the external shape and internal configuration of the object to be grasped are not limited to these examples. For example, it is also possible to grip objects having a square or triangular cross section.

The outer cylinder has an elastic tube as described below disposed inside and has an inner diameter such that an object to be gripped can be gripped therein. The outer cylinder can have a cross-sectional shape of a circle, an ellipse, a square, etc. depending on the cross-sectional shape of the object to be gripped.

The outer cylinder needs to have sufficient strength so that it can support the elastic tube.

The elastic tube can be made of natural rubber, synthetic rubber, etc., for example. The elastic tube has an inner diameter smaller than the outer diameter of the object to be grasped in a state where no tension is applied, that is, in a relaxed state.

The elastic tube is disposed inside the outer cylinder, and both ends of the elastic tube are hermetically connected to an end surface, an outer wall, or an inner wall of the outer cylinder, and the elastic tube and the inner wall of the outer cylinder form a sealed space.

The discharge means is constituted by, for example, a vacuum pump and piping connecting the sealed space and the vacuum pump, and functions to discharge fluid, such as air or nitrogen, in the sealed space.

The supply means includes, for example, a valve that controls communication between the sealed space and the outside. By means of supply,
For example, external atmospheric pressure is supplied within the sealed space.

(Concrete example) A specific example of the external appearance of the gripping device is shown in FIG.

The object to be grasped has a major axis of 15 cm and a minor axis of 10 crn.

Let us take as an example an oval cylindrical pipe with a length of 10 cm and a thickness of 5 mm.

The device of the invention consists of two main parts.

The outer cylinder 1 has a single brim, and its inner diameter must be sufficiently larger than the outer diameter of the object to be grasped. In this example, assuming that there is a variation of ±1 cm in the dimensions of the object to be grasped, the outer cylinder, if it is an elliptical cylinder, must have an inner diameter of 17 cm or more in the major axis and 12 cm or more in the minor axis. is desirable, and if it is a cylindrical outer cylinder, it is desirable that its inner diameter is 17 cm or more. If this inner diameter is not sufficient, it will be difficult to insert the object to be grasped.

In addition, if it is necessary to seal the entire periphery of the object to be grasped,
It is desirable that the length of the outer cylinder is 21 cm or more. Since the adhesion force at both ends of the gripping device is weak, in order to completely seal the gripping device, the cross section of the object to be gripped needs to be located sufficiently inside the cross section of the gripping device outer cylinder.

Another part is an elastic tube, for example a rubber tube 2. The inner circumference of the rubber tube needs to be sufficiently smaller than the outer circumference of the object to be grasped. However, if the object to be gripped is an elliptical cylinder or elliptical cylinder, it may not be possible to completely seal the rubber tube depending on the shape and mounting direction. It is desirable that the diameter is sufficiently smaller than the outer diameter of the object to be grasped. In this example, it is desirable that the circumference of the inner diameter of the rubber tube is 5 cm or more shorter than the circumference of the outer diameter of the object to be grasped. If the shape of the cut surface of the rubber tube is elliptical, it is desirable that the inner diameter of the rubber tube is 13.7 cm or less in length and 8.7 cm or less in breadth. Attach it so that Further, if the shape of the cut surface of the rubber tube is circular, it is desirable that the inner diameter is 8.7 cm or less. Also, regarding the length of the rubber tube, in this example, the rubber tube was folded back into the outer cylinder and fixed with a metal band 3.
cm or more was required. However, the fixing method is not limited to this. The rubber tube has excellent abrasion resistance, elasticity, and chemical resistance, and is preferably made of natural rubber and has a thickness of 2 mm to 4 mm, for example.

In this example, an elliptical cylindrical object is shown as the object to be gripped, but it is obvious that a cylindrical object to be gripped can be similarly gripped by a gripping device by attaching a rubber tube to a cylindrical outer cylinder. Further, an object to be gripped having an elliptical cylinder shape or an elliptical cylinder shape in which there is not much difference in the major axis and minor axis can be gripped by a gripping device in which a rubber tube is attached to a cylindrical outer cylinder.

As shown in FIG. 1, the upper and lower ends of the rubber tube 1 are hermetically connected to the outer cylinder 2 by a metal band 3, and a sealed space 4 (
FIG. 2b) is formed.

This sealed space 4 communicates with the outside via a pipe 5 and a first valve 6. Furthermore, the sealed space 4 is connected to the tube 7 and the second
It communicates with a vacuum pump 9 via a valve 8 .

The gripping device according to this embodiment operates as follows.

First, the vacuum pump 9 is not operating and, for example, the first valve 6 is open, so that the outside and the sealed space 4 are connected to each other.
The pressure inside the sealed space 4 is atmospheric pressure, and as shown in FIGS. 2a and 2b, the diameter of the rubber tube 2 is reduced due to its elastic force. The inner diameter of is smaller than the outer diameter of the object to be grasped.

Next, close the first valve 6 and open the second valve 8,
The vacuum pump 9 is operated to exhaust the air in the sealed space 4. By discharging the air in the sealed air 4, the inner diameter of the rubber tube 2 increases, and the rubber tube 2 comes into contact with the inner wall of the outer cylinder 1, as shown in FIGS. 3a and 3b.

Next, as shown in Figures 4a and 4b, outside *i
Then, the object to be grasped IO is placed inside the rubber tube 2 .

Next, the operation of the vacuum pump 9 is stopped, the second valve 8 is closed, the first valve 6 is opened, the pressure in the sealed space 4 is made atmospheric pressure, the inner diameter of the rubber tube 2 is reduced, and the inner diameter of the rubber tube 2 is reduced. The object 10 to be gripped is gripped by the elastic force of the tube 2 (FIGS. 5a and 5b).

If desired, a pressurized air supply (not shown) can be connected to the first valve 6 to increase the pressure in the sealed space 4 to above atmospheric pressure to increase the gripping force (see Figure 6a). and Figure 6b).

In order to release the grip, the pressure in the sealed space 4 may be reduced by the vacuum means 9 in the reverse order of the above operations.

In the embodiment shown in FIGS. 1 to 6b, the outer tube has an elliptical cross-sectional shape, and the pressure in the sealed space 4 formed between the elastic tube 2 and the outer tube l is equal to atmospheric pressure. At this time, the elastic tube 2 is connected to the outer cylinder 1 such that the central hole of the elastic tube 2 forms an ellipse as shown in FIG. 2a.

Alternatively, in the variant shown in FIGS. 7a and 7b, the outer tube has an elliptical cross-sectional shape, and the elastic tube is attached to the outer tube such that the central hole of the elastic tube forms a circle. connected. In the modification shown in FIGS. 8a and 8b, the outer tube has a circular cross-sectional shape, and the elastic tube is connected to the outer tube such that the central hole of the elastic tube forms an ellipse. . In the modification shown in FIGS. 9a and 9b, the outer tube has a circular cross-sectional shape, and the elastic tube is connected to the outer tube such that the central hole of the elastic tube forms a circle. .

(Comparative Example) As a comparative example, a conventional method of gripping an object by forcibly feeding air into a rubber tube whose inner diameter is sufficiently larger than the outer diameter of the object to be gripped is shown in Fig. 1Oa and Fig. 10b. It is shown in FIG. 11a and FIG. 11b. With this method, wrinkles usually occur in 3 or 4 places, making it difficult to completely seal the outer wall.

The present invention will be explained below with reference to Examples.

(Example 1) An apparatus as shown in Figures 1-6b was used.

In implementation, the inner diameter is 170.0 mm.

A stainless steel cylinder 1 with a minor axis of 130.0 mm and a height of 270.0 mm was used as the outer cylinder. The rubber tube 2 has an inner diameter of 95.0 mm, a thickness of 3.0 mm, and a length of 370.0 m.
A material made of natural rubber was used. Two valved tubes 5 and 7 were attached to the outer cylinder, and one was connected to a vacuum pump 9. The object to be grasped has an outer diameter of 143.0 mm,
Short diameter 98.0mm.

An oval cylindrical ceramic honeycomb with a height of 1.16.6 mm was used.

The cut end of the rubber tube 2 was pushed out and set in the outer tube 1, and the folded portion was fixed with a metal band 3.

When the atmosphere release valve 6 is closed, the vacuum pump valve 8 is opened, and the vacuum pump 9 is started, the rubber tube 2
spreads. At that time, we added protrusions around the air intake to prevent it from becoming blocked.

Insert the object to be grasped into the rubber tube in a direction in which the long axis of the outer cylinder and the long axis of the object to be grasped are parallel, stop the vacuum pump,
When the atmosphere release valve 6 is opened, the rubber tube contracts,
The object to be grasped was grasped.

In addition, with a gripping device of this size, the major axis of the outer diameter is 98 mm.
．． 0mm to 140.0mm and the minor axis is 98.0mm
It was possible to grip the object in a range of -100.0 mm with the outer wall completely sealed.

(Example 2) In implementation, the inner diameter was 115.2 mm and the outer diameter was 165.2 mm.
A stainless steel cylinder with a diameter of 270.0 mm and a height of 270.0 mm was used as the outer cylinder. The rubber tube used was made of natural rubber and had an inner diameter of 95.0 mm, a thickness of 3.0 mm, and a thickness of 370.0 mm. Two valved tubes were attached to the outer cylinder, and one was connected to a vacuum pump. The object to be grasped is
A cylindrical ceramic honeycomb with an outer diameter of 118.4 mm and a height of 150.0 mm was used.

As in Example 1, spread the cut end of the rubber tube,
It was set in an outer cylinder, and the folded part was fixed with metal/(metal).The operating method was also the same as in Example 1.

With a gripping device of this size, the outer diameter is 100.0mm-1
It was possible to grip objects in the range of 40.0 mm with the outer wall completely sealed.

(Effects) As described above, according to the gripping device and method according to the present invention, objects to be gripped that vary in shape and size can be reliably gripped.

Further, according to the gripping device and method according to the present invention, the object to be gripped and the elastic tube of the gripping device are in contact without wrinkles, and the fluid, for example, a liquid for painting only the inside of the object, can be applied to the gripping device. There is no flow in the axial direction between the gripped object and the elastic tube.

Since the elastic tube comes into close contact with the object to be grasped during gripping, when applying liquid only to the inside of the object, the liquid will not flow between the object to be grasped and the elastic tube. Do not allow liquid to adhere to the outer surface of the

Further, according to the present invention, no power is required during gripping, and gripping can be performed even if the elastic tube is damaged, the air piping is damaged, or the connection is disconnected, resulting in extremely high safety.

Furthermore, since no power is required during gripping, only the gripping device can be separated and moved. Therefore, the degree of freedom in designing the mechanical device is large.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a gripping device using an elastic tube according to a preferred embodiment of the present invention. 2a and 2b are a plan view and a central sectional view of the main part of the device of FIG. 1 before the start of operation; FIG. 3a and 3b are a plan view and a central sectional view of the main part of the apparatus of FIG. 1 in a state where the inside of the sealed space is evacuated. 4a and 4b are a plan view and a central cross-sectional view of the main part of the device of FIG. 1 with an object to be grasped placed therein; FIG. 5a and 5b are a plan view and a central sectional view of the main part of the apparatus of FIG. 1 in a state where atmospheric pressure is supplied to the sealed space. 6a and 6b are a plan view and a central sectional view of the main part of the apparatus of FIG. 1 in a state where pressurized air is supplied into the sealed space. 7a and 7b are a plan view and a central sectional view of a main part of a device according to a modification in which the outer tube has an elliptical cross section and the elastic tube has a circular cross section. FIG. FIGS. 8a and 8b are a plan view and a central sectional view of main parts of a device according to another modification in which the outer tube has a circular cross section and the elastic tube has an elliptical cross section. FIGS. 9a and 9b are a plan view and a central sectional view of main parts of a device according to still another modification in which the outer tube has a circular cross section and the elastic tube has a circular cross section. FIGS. 10a and 10b are a plan view and a central sectional view of a main part of a conventional device explained as a comparative example, with an object to be grasped placed inside the device. Figures 11a and 11b are the same as Figures 10a and 10b.
FIG. 2 is a plan view and a central sectional view of main parts showing a grip state of the device shown in the figure. ■...Outer cylinder 2...Elastic tube 3...Metal band 4...Sealed space, first valve, second valve, vacuum pump Figure 10a Figure %lla Figure 10b Figure Figure 11b Figure 4o Figure 4b Figure 5o Figure 5b u Figure 6q Figure 6b Figure 9o Figure 9b

Claims (1)

[Scope of Claims] 1. A pipe-shaped outer cylinder having an inner diameter through which the object to be grasped can easily pass through and having sufficient strength, and an inner diameter through which the object to be grasped cannot pass when no tension is applied. an elastic tube having both ends hermetically connected to the outer tube and forming a sealed space therebetween with the inner wall of the outer tube; a discharge means for discharging fluid from the sealed space; and an elastic tube that discharges fluid from the sealed space; A gripping device using an elastic tube, characterized in that it is equipped with a supply means for supplying fluid to. 2. Drain the fluid in the sealed space formed between the elastic tube and the outer cylinder provided on the outside of the elastic tube, which has an inner diameter that does not allow the object to pass through when no tension is applied. forcibly expanding the elastic tube by: placing an object to be grasped in the elastic tube whose inner diameter has been enlarged; supplying fluid into the sealed space to reduce the inner diameter of the elastic tube; A gripping method using an elastic tube, the method comprising gripping the object to be gripped.