JPH11192513A - Portable motor-driven pipe bender - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a small lightweight portable motor-driven pipe bender with which the necessary bending of a pipe is easily executed at the time of various kinds of piping works. SOLUTION: The rotation of a motor shaft 4 which is decelerated with a reduction gear is transmitted to a feed nut through various kinds of gears, the rotating feed nut is screwed on a feed bolt to which a center shaft 12 at the tip of which a shoe 15 is attachably and detachably provided is connected in the front part, the feed bolt is moved forward and backward. By inserting a material to be worked such as the pipe between a pipe guide member 18 which is detachably fixed on the upside of the jaw part 14 in the front part of the main body 1 and the shoe 15, bending is executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small and lightweight portable electric pipe bender capable of easily bending pipes necessary for various piping work including air conditioning equipment.

[0002]

2. Description of the Related Art Conventionally, in bending pipes necessary for various piping work such as air conditioning equipment, a second handle is used as a first handle as disclosed in, for example, Japanese Utility Model Publication No. 56-66250. By pivotally supporting and swinging the second handle, the feed pawl pivotally supported by the second handle engages with pawl teeth formed on a rod provided on the first handle to advance the rod. Hand-operated benders that bend pipes through a shoe at the tip of a rod have been widely used. However, in the manual bender, the pitch of the claw teeth formed on the rod cannot be taken so small due to problems in processing and strength, and is generally formed at a relatively large pitch. In order to obtain, a considerable force is required for the swing operation. In order to make the handle operation lighter, it is necessary to increase the length of the handle. Has a problem that it is very difficult to handle, and bending a large number of pipes is a heavy burden for the operator.

In order to solve the problem in the manual type bender, Japanese Utility Model Publication No. Sho 61-10814 discloses a main shaft having a bending shoe attached to one end or capable of being slid only in the axial direction. A lever which is supported by a gripping frame, has a serrated engagement portion formed at a constant pitch on the peripheral surface of the main shaft along the axial direction of the main shaft, and is pivotally attached to the frame so as to be capable of reciprocating swing operation. A plurality of feed claws are provided on the tip end side of the lever to engage the locking portion when the lever slides in either one of the reciprocating directions and slide the main shaft toward the bending shoe. The interval between the plurality of feed claws is set such that the plurality of feed claws are selectively and sequentially engaged with the saw-tooth-shaped locking portion with the reciprocating swing operation of The stop is relatively large Be formed in the pitch, is disclosed advantageous Ben Day ring tool operation surface requires only operating force sufficient to obtain a substantial amount of feed of a plurality fraction of the pitch of the serrated locking part. This bending tool has succeeded in preventing an increase in required operating force due to miniaturization. However, in other words, if the bending tool is provided with a plurality of feed claws, the lever must be reciprocated several times in order to obtain a feed amount of one pitch of the serrated locking portion. And the overall length of the lever can be shortened and the whole can be miniaturized, but the number of reciprocating swing operations of the lever increases accordingly, which also has a problem when bending a large number of pipes.

[0004] An electric pipe bending apparatus as disclosed in Japanese Patent Publication No. 1-52091 is known as an apparatus for bending a pipe by electric power. This electric pipe bending apparatus reduces the rotation of a motor by a speed reducer, is fixed to an output shaft of the speed reducer, and has a rotary former having a holding groove corresponding to a bent cross section of the pipe; A pipe holder that is provided on the outer peripheral portion and holds the vicinity of the bending start portion of the pipe, and holds the pipe integrally with the rotary former during rotation of the rotary former, and is installed at a fixed position so as to sandwich the pipe between the rotary former. And a bending die having a guide groove for guiding the pipe while sliding it in the axial direction substantially opposite to the holding groove of the rotary former, and rotating the semi-circular rotary former by a motor, This is a pipe bending device for winding a pipe around an outer periphery of a rotary former and bending the pipe. Actually, a mechanism employing the mechanism disclosed in Japanese Patent Publication No. 1-52091 has been widely commercially available. However, it is suitable for mass production of pipe bending work in factories, etc., because it has a complicated structure and is very heavy and requires a power outlet, but it is very inconvenient to carry it at the piping work site. Things.

[0005]

As described above, the conventional manual bender requires a large-sized device to reduce the operating force, and requires a considerable amount of operating force if the device is reduced in size. In order to reduce the size and reduce the operating force, the number of reciprocating swing operations of the lever increases, and in any case, bending a large number of pipes is a heavy burden on the operator.
In the case of electric benders,
Japanese Patent Application Laid-Open No. 52091 discloses a mechanism employing the mechanism disclosed in Japanese Patent Application Publication No. 52091. However,
It is suitable for mass production of pipe bending work in factories, etc., because its structure is complex and very heavy, and it requires a power outlet, but it is very inconvenient to carry it at the piping work site. is there.

As described above, the conventional benders described above have not been able to sufficiently satisfy the problem of achieving both a reduction in size and weight and a reduction in labor, both in the manual type and the electric type. In particular, in plumbing work for condominiums and buildings, continuous and large-volume pipe bending work is often carried out while carrying a bender, and the conventional bender places a heavy burden on workers. In view of such circumstances, an object of the present invention is to reduce the size and weight of pipes necessary for various plumbing operations, especially for continuous and large-volume pipe bending easily as in the plumbing operations of condominiums and buildings. It is to provide a portable electric pipe bender.

[0007]

SUMMARY OF THE INVENTION In order to solve the problems of the conventional bender, a portable electric pipe bender according to the present invention comprises a shaft having a detachable shoe at a tip thereof, and a shaft facing the shoe. A pipe guide member is detachably fixed to a main body at a position, the shaft is moved forward and backward, and a workpiece such as a pipe is bent by sandwiching the work between the shoe and the pipe guide member. The pipe guide member is detachably fixed to the
The rotation of the motor shaft is reduced by a reduction mechanism, and the reduced rotation is transmitted to a feed nut supported on the main body so as to be rotatable and unable to advance and retreat in the axial direction. A feed bolt supported on the main body so as to be able to move forward and backward, and a center shaft that moves forward and backward integrally with the feed bolt are provided, and a shoe is detachably provided at the tip of the center shaft, and the feed nut is rotated by rotation of the feed nut. A workpiece such as a pipe is bent by moving the feed bolt and the center shaft forward and backward.

Further, in the second portable electric pipe bender according to the present invention, the rotation of the motor shaft reduced by the speed reduction mechanism is transmitted to the driven shaft, and the rotation is transmitted to the gear and the feed nut provided on the driven shaft. The fixed gear is engaged with the feed nut so that the axis of the feed nut is parallel to the motor shaft, thereby shortening the overall length of the main body and being able to cope with a narrow work space.

Further, in a third portable electric pipe bender according to the present invention, the feed bolt is disposed coaxially rearward of the feed nut, and when the feed bolt is at the maximum retracted position, the screw with the feed nut is screwed. The main body can be prevented from being damaged by arranging the feed nuts so as to cancel each other and idling only the feed nut. In addition, by providing an urging member for pressing the feed bolt against the feed nut behind the feed bolt, the feed bolt can be screwed if the feed nut rotates in a direction to advance the feed bolt even when the screwing is released. It is characterized by combining.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a portable electric pipe bender according to the present invention will be described in detail with reference to the drawings. In FIGS. 1 and 2, reference numeral 1 denotes a main body for protecting and holding an internal mechanism, and is preferably made of a resin such as polycarbonate for weight reduction as in many electric appliances. Reference numeral 4 denotes a motor shaft of a motor 3 that rotates by using a battery 2 at a lower portion of the main body 1 as a power source.
Is transmitted to the front driven shaft 6 having the gear 7 at a reduced speed.

A wide gear 8 is provided above the driven shaft 6 and is supported by the main body 1 so as to be rotatable and unable to move back and forth in the axial direction.
A feed nut 9 having a trapezoidal female thread is provided in parallel with the motor shaft 4. The wide gear 8 meshes with the gear 7 of the driven shaft 6, and rotation is transmitted to the feed nut 9.

A feed bolt 10 screwed with the feed nut 9 is housed in a case 25 provided integrally with the main body 1 behind the feed nut 9 on a coaxial line so that the feed bolt 9 cannot rotate and can advance and retreat in the axial direction. The feed bolt 10 is supported by the main body 1.
Moves forward and backward by the forward and reverse rotation of the motor 3.

When the motor 3 is reversed, the feed bolt 10
When the feed bolt 10 reaches the maximum retreat position, that is, the rear end of the case 25, when the feed bolt 10 and the feed nut 9 are screwed and the motor 3 continues to rotate in the reverse direction, the resin When the feed bolt 10 reaches the rear end of the case 25, the screw engagement with the feed nut 9 is released because the rear end of the case 25 made of 25 is slightly longer than the length of the feed bolt 10 in the axial direction, and even if the motor 3 continues to rotate in the reverse direction, only the feed nut 9 idles and the feed bolt 1
By not transmitting the power to the main body, the main body is prevented from being damaged.

One end of the feed bolt 10 is fixed to the rear end of the case 25, and the other end of the feed bolt 1 is fixed to the rear end of the case 25.
Compression coil spring 1 that presses 0 to the front feed nut 9
By providing 1, the feed nut 9 and the feed bolt 10 are immediately screwed together if the motor 3 is rotated forward even if the feed bolt 10 is at the maximum retracted position and the screwing is released.

The feed bolt 10 is fitted to the rear end of the center shaft 12 through a fitting hole 13 provided at a front portion, and a spring pin 19 is inserted into a hole formed at each fitting portion. The center shaft 12 penetrates the feed nut 9 and is slidably supported by the main body at the front via a bush 17. When the feed bolt 10 is at the maximum retracted position, the tip protrudes slightly from the bush 17. It is arranged to be.

The center shaft 12 has a bush 17.
Is formed in an angular cross section at a portion slidably supported by the main body, so that the feed bolt 10 connected at the rear end of the center shaft 12 cannot rotate and reciprocates in the axial direction. Supported as possible. Further, the center shaft 12 protrudes from the bush 17 to form a bending curve of the pipe and has a semi-circular shoe 15 having a substantially U-shaped groove on the circumferential surface corresponding to the cross-sectional shape of the pipe.
Is attached detachably.

A pipe guide member 18 is provided on the upper surface of the jaw 14 at the front of the main body 1 so as to face the shoe 15 so as to be attachable and detachable. A pair of pipe support members 16 having a U-shaped groove are pivotally supported.

If the operation switch 22 is a momentary type in which the motor is operated only when the switch is pressed and the switch is turned off and the motor stops when the hand is released, accidents due to mischief or carelessness can be prevented. Further, it is preferable to provide a breaker 23 that cuts off the current of the circuit when an excessive load is applied to the motor due to a foreign object or the like.

FIGS. 5 and 6 show a state in which the pipe guide member 18 is mounted on the guide support 20 in an inverted manner.
Is connected to a portion of the center shaft 12 protruding from the bush 17, a reverse action base 21 is extended on the jaw 14 at the front part of the main body 1, and a shoe 15 is mounted on the reverse action base 21, so-called This is an embodiment having a function of a reverse-action bender, and is convenient when the pipe is bent along a convex wall surface or the like in a state where one end of the pipe is fixed by a pipe joint or welding.

The above is literally an example, and the present invention can of course be carried out based on the common knowledge of those skilled in the art with various modifications and improvements made to solve the problems of the present invention. However, the present invention is not particularly limited to the above-described embodiment within a range of common knowledge of those skilled in the art.

[0020]

According to the present invention, the rotation of the motor shaft is reduced by the reduction mechanism, and the reduced rotation is transmitted to the feed nut supported on the main body so as to be rotatable and unable to advance or retreat in the axial direction. A feed bolt screwed to the nut and supported by the main body so that it cannot rotate and can move forward and backward in the axial direction, and a center shaft that moves forward and backward integrally with the feed bolt are provided, and a shoe is attached to and detached from the tip of the center shaft. The workpiece such as a pipe is bent by moving the feed bolt and the center shaft forward and backward by rotating the feed nut. As a method of converting rotary motion into linear motion, power transmission efficiency is better than when using rack gears and pinion gears, and sufficient power to perform pipe bending even with a motor with relatively small output. Can be obtained, which is also advantageous in terms of reduction in size and weight and cost.

Further, in the present invention, the rotation of the motor shaft is reduced by the planetary gear device, and a driven shaft having a gear is disposed coaxially with the planetary gear device, and the rotation reduced by the planetary gear device is reduced. The transmission is transmitted to the driven shaft, the gear provided on the driven shaft and the gear fixed to the feed nut mesh with each other, and the length of the main body is shortened by arranging the feed nut so that the axis is parallel to the motor shaft. And can be used in narrow work spaces.

Further, the feed bolt is disposed coaxially rearward of the feed nut, and when the feed bolt is at the maximum retracted position, the screw is disengaged from the feed nut so that the operation switch is kept pressed. In this case, the main body can be prevented from being damaged by idling only the feed nut.

Further, by providing an urging member for pressing the feed bolt against the feed nut behind the feed bolt, even if the screw nut is released, the feed nut can be rotated in a direction to advance the feed bolt. The feed nut and feed bolt are immediately screwed together.

As described above, the portable electric pipe bender according to the present invention can easily perform bending of pipes necessary for various piping work including air conditioning equipment, and is small in size, light in weight and labor saving. Therefore, the problem of satisfying both can be sufficiently satisfied, and has a great use value.

[Brief description of the drawings]

FIG. 1 is a central vertical sectional view of a pipe bender according to the present invention.

FIG. 2 is a plan view of a pipe bender according to the present invention.

FIG. 3 is a central longitudinal sectional view at the time of pipe bending in a pipe bender according to the present invention.

FIG. 4 is a plan view of the pipe bender according to the present invention at the time of pipe bending.

FIG. 5 is a central longitudinal sectional view of an embodiment of the pipe bender according to the present invention having an adverse effect bender function.

FIG. 6 is a plan view of an embodiment of the pipe bender according to the present invention, which has a counter-action bender function.

[Explanation of symbols]

1 body 2 battery 3
Motor 4 Motor shaft 5 Reduction mechanism 6
Driven shaft 7 gear 8 wide gear 9
Feed nut 10 Feed bolt 11 Compression coil spring 12
Center shaft 13 fitting hole 14 jaw 15
Shoe 16 Pipe support member 17 Bush 18
Pipe guide member 19 Spring pin 20 Guide support 21
Reverse action base 22 Operation switch 23 Breaker 24
Workpiece 25 Case 100 Portable electric pipe bender

Claims (3)

[Claims] 1. A shaft having a shoe detachably provided at a tip thereof, a pipe guide member being detachably fixed to a main body at a position opposed to the shoe, and moving the shaft forward and backward to move between the shoe and the pipe guide member. In a bender that bends a workpiece such as a pipe by sandwiching the workpiece in a bender, the rotation of the motor shaft is reduced by a reduction mechanism, and the reduced rotation is rotatable and cannot move forward or backward in the axial direction. A feed bolt transmitted to a supported feed nut, screwed with the feed nut, supported on the main body so as to be non-rotatable and capable of moving back and forth in the axial direction, and a center shaft that moves forward and backward integrally with the feed bolt are provided. A shoe is detachably provided at the tip of the center shaft, and the feed nut and the center shaft are moved forward and backward by rotation of the feed nut to process a pipe or the like. A portable electric pipe bender characterized by bending objects. 2. The rotation of the motor shaft decelerated by the reduction mechanism is transmitted to a driven shaft, and a gear provided on the driven shaft and a gear fixed to a feed nut mesh with each other, and the axis of the feed nut is 2. The portable electric pipe bender according to claim 1, wherein the portable electric pipe bender is arranged so as to be parallel to the axis. 3. The feed bolt is disposed coaxially rearward of the feed nut, and is disposed so as to be disengaged from the feed nut at the maximum retreat. The feed bolt is disposed behind the feed bolt. The portable electric pipe bender according to claim 1, further comprising an urging member that presses the feed nut.