US3380283A

US3380283A - Tube bending tool

Info

Publication number: US3380283A
Application number: US424535A
Authority: US
Inventors: Frank R Wilson; John H Stanley
Original assignee: Parker Hannifin Corp
Current assignee: Parker Hannifin Corp
Priority date: 1965-01-11
Filing date: 1965-01-11
Publication date: 1968-04-30
Anticipated expiration: 1985-04-30

Description

April 30, 1968 R w so ET AL 3,380,283

TUBE BEND ING TOOL 3 Sheets-Sheet 1 Filed Jan. 11, 1965 INVENTORS 3 FQfi/VK 1?. W/zso/v i JOHN H. s TH/VLEY Y ATTORNEY April 30, 1968 F. R. WILSON ET AL 3,380,283

TUBE BENDING TOOL Filed Jan. 11, 1965 3 Sheets-Sheet 2 INVENTORS FQfi/VK E Mason) 4 Jog/v 15 STHIVLEY ATTORNEY April 30, 1968 R WILSON ET AL 3,380,283

TUBE BENDING TOOL 5 Sheets-Sheet 3 Filed Jan. 11, 1965 United States Patent M 3,380,283 TUBE BENDING TOOL Frank R. Wilson, Memphis, Tenn., and John H. Stanley,

Euclid, Ohio, assignors to Parker-Hannifiu Corporation, Cleveland, Ohio, a corporation of Ohio Filed Jan. 11, 1965, Ser. No. 424,535 6 Claims. (Cl. 72-387) ABSTRACT OF THE DISCLOSURE A tube bending tool including a shoe, a circular arbor and an elongated link pivotally connected by pins at opposite ends of the link to the shoe and arbor, respectively; the distance between the pivot pins being greater than the sum of the radius of the arbor seat and the distance between .the shoe pin and the longitudinal axis of the shoe seat, and releasable means for locking the shoe and arbor in a closed position in which the arbor seat and shoe seat engage the tube.

This invention relates to a tube bending tool, and more particularly to a portable hand tool for bending a tube.

Heretofore, portable tube bending tools have included an arbor and a shoe pivotally connected to the arbor for rotation about the arbor to bend a tube. However, in order to open the tool to receive the tube, the shoe has to be pivoted relative to the arbor, so that the handle on the shoe is swung upwardly and away from the tube. This type of tool operates satisfactorily where plenty of room for pivoting the shoe and shoe handle is available. However, such a tool could not be used where the available space is limited, since the tool could not be opened and closed to receive and release the tube.

It is therefore an object of this invention to overcome the above disadvantages by providing a tube bending tool in which the shoe and the arbor may be moved away from each other for receiving the tube without rotating the shoe relative to the arbor.

Another object of this invention is .to provide a portable tube bending tool which may be operated in limited spaces.

A further object of this invention is to provide a portable tube bending tool including a shoe and an arbor, and a link pivotally connecting the shoe and the arbor in offset relationship so that the shoe and arbor may be swung toward and away from each other between a closed and an open position, without changing the angular relationship of the shoe and the arbor.

A further object of this invention is to provide a portable, manual, tube bending tool which may be operated with a minimum of head space.

Another object of this invention is to provide a portable tube bending tool including means for locking the shoe relative to the link in closed tube bending position for establishing a predetermined fixed radial position of the shoe relative to the arbor.

Another object is to provide a portable tube bending tool in which the shoe and arbor are each pivotally connected to a link that in one position of the link relative to the shoe and arbor separates the same so as to permit insertion of a tube therebetween and in another position closes the shoe against the tube, and there being a means to releasably lock the pivotal position of the shoe relative to the link when the shoe is in such closed position.

Further objects and advantages of the invention will be apparent from the following description taken in conjunction with the drawings, wherein:

FIGURE 1 is a side elevation of the invention in open position;

3,386,283 Patented Apr. 30, 1968 FIGURE 2 is a front end elevation of the invention disclosed in FIGURE 1;

FIGURE 3 is an elevation of the opposite side of the invention in closed position;

FIGURE 4 is a rear end elevation of the invention disclosed in FIGURE 3;

FIGURE 5 is a side elevation of an optional form of the invention in closed position; and

FIGURE 6 is a rear elevation of the invention disclosed in FIGURE 5.

Referring now to the drawings in more detail, the tool 10 for bending an elongated tube or rod 11 includes a circular arbor 13 and a shoe I14. The arbor 13 is provided with an annular recess or seat 16 having a cross section adapted to conform in size and shape to the cross section of the tube 11, as disclosed in FIGURES 2 and 4. Fixed to one side of the arbor 13 is a housing 17 in which is dependingly mounted an elongated lower or arbor handle 18.

Pivotally mounted on the rear end or edge of the arbor 13 is a book 20 secured by a pivot pin or bolt 21. The length and size of the hook 20 are such that when it is swung to operative position, disclosed in the drawings, it will engage the top of the tube 11 when the tube :11 is received in the arbor seat 16 in its initial or stationary position. The portion of the tube 11 to the rear of the arbor 13 is held in this stationary position by the hook 20 during the bending operation, disclosed in FIGURE 3.

The shoe 14 has a front end or face 24 and a rear end 25 having a lower cut-out portion 26 adapted to clear the hook 20 when the tool is in its operative closed position, as disclosed in FIGURE 3. The bottom of the shoe 14 comprises a straight elongated seat 27 having an arcuate cross section adapted to oppose the arbor seat 16 and engage the top portion of the tube 11, as disclosed in FIGURES 3 and 4. Rigidly secured in the shoe r14 and extending forwardly from the front face 24 is the elongated upper or shoe handle 28. The handle 28 extends generally forwardly, but diverges slightly from the tube 11 in order to provide leverage and gripping room for manipulating the shoe handle 28.

Connecting the arbor 13 and the shoe 14 together is a link or link bar 30 having a rear end or face 31, an inclined upper forward face 32 and a lower inclined face 33. A lower pivot pin 35 pivotally connects the lower end of the link 30 to the arbor 13 so that the pivotal axis of the pin 35 coincides with the center of the circular arbor 13. An upper pivot pin 36 is fixed in the rear portion of the shoe 14 and extends through an elongated slot 37 in link 30 in slidable and pivotal engagement therewith. For the purposes of this invention, the longitudinal axis 40 of the link 30 will be considered as the line of centers extending through the pivotal axis of the lower pin 35 and the pivotal axis of the upper pin 36 when the pin 36 is seated in the upper portion of elongated slot 37, as disclosed in FIGURES 1 and 3.

Formed in the lower front face 33 of the link 30 is an open ended locking slot 42 which is adapted to receive in closed position, as indicated in FIGURES 3 and 4, a locking pin 43 fixed in the lower portion of the shoe 14. The axis of the elongated slot 37 is directed generally toward the slot 42 and the latter is of a sufiicient angle and length to permit the pin 43 to be easily inserted and removed from slot 42 when the shoe 14 is pivoted about the pin 36 between its open position disclosed in FIG- URE 1 and its closed position disclosed in FIGURE 3.

The operation of the invention is disclosed in the drawings, particularly FIGURES 1 and 3. Assuming that the tool 10 includes a circular arbor 13 having the appropriate seat 16 for receiving a correspondingly sized tube 11 for bending, the handle 18 is grasped by one hand of the operator, for example, his left hand and the upper handle 28 is grapsed by the right hand and the shoe 14 is moved to the open position disclosed in FIGURE 1. It will be noted that the upper pivot pin 36 is raised to the disclosed upper position in the slot 37 to provide the maximum space between the

seats

16 and 27. In this initial position, the hook 20 will be hanging down from its pivot pin 21 in an inoperative position, not shown. The tube 11 is then inserted longitudinally between the

seats

16 and 27 so that it rests upon the upper portion of the arbor seat 16. Alternatively, the tube may be inserted laterally from the side opposite link 30 by rotating the tube a few degrees in a counterclockwise direction from the position shown in FIGURE 1, in which case the tube will readily pass sidewards between the lower corner of cut-out portion 26 and arbor 13 because the latter are then spaced apart a distance slightly greater than the diameter of the tube. The hook 20 is then rotated upwardly and over the top of the tube 11 to hold the tube 11 in its initial stationary position illustrated in FIGURES l and 2.

The tool is then closed by thrusting the handle 28 rearwardly causing the link 30 to pivot about the

pivot pins

35 and 33 and also to swing rearwardly to the closed position illustrated in FIGURE 3, with the shoe seat 27 engaging the top portion of the tube 11. In moving the shoe 14 rearwardly, the pivot pin 36 moves toward the bottom end of slot 37 so that the locking pin 43 will ride downwardly over the upper forward face 32 of the link 30 and continue down the lower forward face 33 until the pin 43 is seated in the slot 42, as indicated in FIGURE 3. The rearward movement of the shoe 14 is continued until the pin 36 again is seated in the upper portion of slot 37, as illustrated in FIGURE 3. With the shoe 14 locked in the closed position of FIGURE 3, the operator presses downwardly on the upper handle 28 in a clockwise direction, as viewed in FIGURE 3, to cause the shoe 14 to bend a portion 11' of the tube 11 between the

seats

16 and 27 to any desired position, such as illustrated in FIG- URE 3.

In order to determine the degree of bending, radial gauge marks 45 may be provided on the side face of the arbor 13 and an indicator mark 46 may be formed on the same side face adjacent the bottom of the shoe 14 as disclosed in FIGURE 3. Thus, as the shoe is rotated, the indicator mark 46 will designate the degree of bend when it registers with each successive gauge mark 45, depending upon the calibration of the marks 45.

After the tube 11 has been bent to the desired angle, such as tube portion 11, the movement of the handle 28, and consequently the shoe 14, is reversed until it reaches the initial closed position disclosed in FIGURE 3. The handle 28 is then pulled forwardly, initially moving the shoe 14 to disengage the locking pin 43 from slot 42, and then rotating the link 30 to its open position, disclosed in FIGURE 1. The hook 20 is then counter-rotated to disengage the tube 11 and the bent tube is removed.

It will be noted that as the handle 28 is rotated in its closed position to bend tube 11, the thrust of the shoe 14 will be such as to cause the upper pivot pin 36 to remain in the upper portion of elongated slot 37 and also to thrust the locking pin 43 against the closed side of the slot 42, so that the shoe 14 will remain in locked position during the bending operation.

It will be further noted by observing the closed position of FIGURE 3 and the open position of FIGURE 1 that the handle 28 and the shoe 14 maintain the same relative rotational or angular position with respect to the arbor 13 and the handle 18. The only head space required for the shoe 14 and the handle 28 will be equal to the difference in the spacing between the arbor seat 16 and the shoe seat 27 in closed and open positions. Thus, because the length of the link 30 permits the pivotal axis of the upper pin 36 to be offset longitudinally from the axis of the lower pivot pin 35, the tool may be opened and closed without the necessity of swinging the shoe 14 and the shoe handle 28 upwardly about the pivot pin 36, which would require substantial head room. Therefore, the bending tool 10 can be employed for bending tube 11 in limited spaces, areas with limited room and areas not readily accessible for manipulation of the tool by hand.

In the modification of the invention shown in FIG- URES 5 and 6, link 50 is substituted for link 30 of FIG- URE l and it has a circular opening 51 instead of an elongated slot 37 for receiving the pivot pin 36. Also, pin 43 and slot 42 are omitted. Instead, a book 52 is pivotally mounted on a pin 53 which is secured to the forward end of shoe 14 and which has an enlarged central portion 54 for spacing hook 52 from shoe 14. Housing 17 has a pin 55 extending therefrom on the center of circular arbor 13 and hook 52 has a slot 56 for engaging pin 55.

To operate thhis form of the invention, hook 52 is initially swung upwardly to the dotted position shown in FIGURE 5, at which time shoe 14 may be moved forwardly for rotating link 50 to a position corresponding with FIGURE 1 in which the longitudinal axis 40 is perpendicular to the axis of tube 11 in the stationary position of the latter. With the parts in this position, tube 11 may be inserted laterally between the shoe and arbor and into the seat 16 of the latter. After hook 20 is swung over the tube, the shoe 14 may then be moved rearwardly to the position shown in FIGURE 5 and hook S2 swung downwardly to engage pin 55 in slot 56. This locks shoe 14 in its angular relationship with link 50 and the shoe may now be operated for bending the tube.

After the bend is completed, hook 52 is again swung into the position shown in the dotted line in FIGURE 5, shoe 14 is moved forwardly and the tube may then be removed from the bender.

This arrangement not only provides an optional method of locking the angular relationship between the shoe and link 50 during the bending operation but also ties the shoe and arbor together so that there is a connection between the shoe and arbor on each side thereof, link 50 providing the connection on the opposite side. This imparts considerable rigidity to the assembly and prevents any springing action that would tend to separate the shoe and arbor during the bending operation.

It will be apparent to those skilled in the art that various changes may be made in the invention without departing from the spirit and scope thereof, and therefore the invention is not limited by that which is shown in the drawings and described in the specification, but only as indicated in the appended claims.

What is claimed is:

d. A tool for bending a tube comprising:

(a) an arbor having a seat for receiving said tube, said seat being circular in the bending plane of said tube,

(b) means adjacent one end of said arbor for holding one portion of said tube in a stationary position relative to said arbor,

(c) a shoe having a seat with a longitudinal seat axis in said bending plane, said shoe seat opposing said arbor seat for engaging said tube,

(d) a link having a longitudinal link axis, an upper end and a lower end,

(e) a first pin pivotally connecting said lower end on said link axis to said arbor at the center of said circular seat,

(f) a second pin pivotally connecting said upper end on said link axis to said shoe to permit relative pivotal movement between said link and said shoe,

(g) the distance between said first and second pins on said link axis being greater than the sum of the radius of said arbor seat and the distance between said second pin and said seat axis,

(h) said shoe being movable between an open position in which said link axis is perpendicular to said seat axis, and a closed position in which said link axis forms an acute angle with said seat axis and said shoe seat and arbor seat engage said tube,

(i) handle means for moving said shoe between said open and closed positions, and for rotating said shoe in closed position around said arbor in said bending plane,

(j) a first locking member on said shoe,

('k) a second locking member on said link adapted to operatively engage said first locking member when said shoe and link are in closed position, and

(1) means for releasably maintaining said first and second locking members operatively engaged,

2. The invention according to claim 1 in which said one end of said arbor is said rear end, said link having a front edge, said second locking member comprising an open slot in said front edge, said first locking member comprising a locking pin projecting from said shoe for engagement with said open slot when said shoe is rotated to said closed position, said releasably maintaining means comprising an elongated slot in said link for receiving said second pin to facilitate the engagement and disengagement of said locking pin with said open slot.

3. The invention according to claim 2 in which said elongated slot extends in a direction generally toward said open slot.

4. The invention according to claim 2 in which said elongated slot extends at an acute angle with said link axis.

5. The invention according to claim 2 in which said elongated slot has one end remote from said arbor, and said second pin is in alignment with said link axis when said second pin is received in said remote end.

6. The invention according to claim 2 in which, when said shoe is in said closed position engaging a tube, only a portion of said shoe seat projects toward a said holding means from a line perpendicular to said seat axis passing through the center of said circular seat, and the entire shoe seat is on the opposite side of said line from said holding means when said link axis is perpendicular to said seat axis.

References Cited