US2936193A - Switch stick - Google Patents

Description

May 10, 1960 B. F. MANNEN SWITCH STICK 2 Sheets-Sheet 1 Filed June 16, 1958 e l RNEYS INVENTOR BENONA FRANK MANNEN BY: I

B. F. MANNEN May 10, 1960 SWITCH STICK 2 Sheets-She Filed June 16, 1958 INVENTOR BEND/VA FRANK MAN/VE/V 8): a ATTORNEYS United States Patent SWITCH STICK Benona Frank Mannen, St. Thomas, Ontario, Canada Application June 16, 1958, Serial No. 742,255

6 Claims. (Cl. 29419) This invention relates to switch sticks. Such sticks are employed for the manipulation of fuse members in high voltage distribution systems, such systems carrying voltages, for example, of 120 kilovolts.

Such [uses are normally mounted in disconnecting mountings, the fuse member being gripped at its ends by a pair of vertically spaced supporting members. The lower end of the fuse member is provided with transversely extending pivot pins which cooperate with notched arms in the lower supporting member. To dis connect the fuse, the upper end of the fuse member is pulled out of its supporting member by the switch stick and is then pivoted about the pins, which are received in the notched arms in the lower members, until the fuse member attains a vertical position in which it is upside down. The fuse member is then removed from the lower. member by the switch stick.

A common type of switch stick has a projecting knob at one end, the knob being arranged to co-operate with loops at the ends of the fuse member. To disconnect the fuse, the knob is caused to enter the loop at the upper end of the fuse member so that the upper end of the fuse member may be pulled out of its support and pivoted about the lower support as previously described. The fuse member is removed from the lower support by engaging the knob. with the loop at the lower end of the fuse member and by lifting the fuse member to disengage the pivot pins from the notched arms on the lower support member.

In high voltage systems, line fuse members are comparatively heavy, for example, a typical fuse member Weighs 38 pounds. Moreover, the disconnecting mountings are usually arranged at some distance above the ground to prevent unauthorized interference. A normal distance above the ground for such a fuse is some 15 or 16 feet. It will be appreciated that, when it is necessaryto replace a fuse, it is necessary to lift the fuse member, weighing some 38 pounds, at the end of a switch stick 15 feet long, which is a difficult operation. The normal procedure is that the knob at the end of the stick is engaged in the loop at the lower end of the fuse member, the fuse member is then lifted until the pivot pins engage in the notched arms on the lower support of the fuse mounting, the knob is then removed from the loop at the lower end of the fuse member and inserted into the loop at the upper end of the fuse member, and finally the fuse member is swung around by the stick so that the upper end of the fuse member engages the upper support of the disconnecting mounting. To lift the fuse member up to the mounting and to engage the pivot pins in the notched arms is a very arduous operation.

An object of the present invention is to provide a switch stick which facilitates the elevating and lowering of fuses to and from elevated fuse mountings.

A further object of the invention is to provide a switch stick in which a fuse may be elevated or lowered by means of a force which is less than the weight of the fuse.

2,936,193 Patented May 10, 1960 These objects are achieved by a switch stick which includes a carrier slidable along the stick, means operable from adjacent one end of the stick to slide the carrier along the stick, means on the carrier for releasably supporting a fuse member, and means adjacent to the other end of the stick to engage a fuse mounting to support the stick therefrom during movement of the carrier and the fuse member along the stick.

The invention will now be described by way of example with reference to the accompanying drawings, in which like reference numerals indicate similar parts throughout the several views and in which:

Figure l is a perspective view, partly broken away, of a switch stick according to the invention,

Figure 2 is a cross-section on the line II--II of Figure 1,

Figure 3 is a cross-section on the line IIIIII of Figure 1,

Figure 4 is a general perspective view showing the switch stick in use, and

Figure 5 is a perspective view of a fuse mounting with thefuse member in operative position, the fuse member being shown in disconnected position in phantom lines.

Referring now to the drawings, the switch stick comprises a shaft 16 which may be conveniently about 15 feet long and 2 inches in diameter. The shaft may be made from sitka spruce which has been dried and varnished.

At the upper end of the shaft is mounted a head, indicated generally at 14, the head including a sleeve portion 15 which fits over a reduced portion 16 atthe upper end of the shaft. The head may conveniently be cast of aluminum alloy and includes a pair of spaced plate members 17 each of which is formed with an integral lug 18 on its external surface. A first pulley 19 is rotatably mounted between the plate members 17 on an axis formed by a bolt 20 which extends transversely of the stick and through the lugs 18 and the plate members 17. At their upper ends the plate members 17 are curved to have substantially semi-circular ends which are embraced by a semi-circular cover plate. The cover plate 21 is maintained in position by screws 22 received in threaded holes in theplate members 17.

Interposed between the head of the bolt 20 and one of the lugs 18 is a sheet metalv hook member 23 having a retroverted end 24. The threaded end of the bolt 20 is received in a threaded hole in a boss 25 from which projects a shaft 26 terminating in a tapered knob 27. The assembly of boss 25, shaft 26 and knob 27 is removable from the bolt 20 whereby a variety of forms of hook member '23 may be mounted on the head to suit different forms of fuse support encountered in use.

Mounted in the shaft adjacent to the lower end thereof is a pulley sheave comprising sheave plates 29 and a pulley 30. The sheave is received in an aperture 31 in the shaft 10 and is retained in position by pins 32 passing through the shaft and the plates 29. The pulley 30 is mounted for rotation about a pin 33 parallel to the bolt 20 which forms the axis of the first pulley 19.

A carrier, indicated generally at 34, embraces the shaft 10 and includes a pair of arcuate members 35 which embrace the shaft 10 and terminate in lugs 36, a pair of lugs 36 being provided at the ends of each arcuate member 35. A second pulley 37 is rotatably mounted upon a pin 38 between the lugs 36 of the upper arcuate member 35, and a third pulley 39 is mounted for rotation about a pin 40 between the pair of lugs 36 of the lower arcuate member 35. The ends of the pins 38 and 40 are riveted over to retain the lugs 36 of each pair in opposed relation. The carrier also includes longitudinal stringers 41 which extend between thearcuate members 35 and their respective lugs 36. The stringers 41 support a hook 142 which is arranged, as will hereinafter be described, to receive a loop of a fuse member.

The shaft 10 is formed with a longitudinal groove 42 extending from adjacent to the lower pulley sheave to the head of the stick; the groove is continued at 42a in the head 14. A rope, indicated generally at 43, has one end anchored at a first anchorage 44 in the head of the stick. The rope passes from the first anchorage 44, down the groove 42, around the second pulley 37, then upwardly and over the first pulley 19, then downwardly outside the shaft of the stick, around the pulley 38, which is hereinafter called the fourth pulley, then upwardly over the third pulley 39, and downwardly along the groove 42; the other end of the rope being anchored in a second anchorage 45 adjacent to the fourth pulley. The downwardly extending portion of the rope which passes out-. side the stick between the first pulley 19 and the fourth pulley 30 is indicated at 46. The rope may Conveniently consist of a cotton string core with an extruded plastic covering.

It will be apparent that if a point on the portion 46 of the rope is moved towards the bottom of the stick the carrier 24 will move upwardly along the stick. Conversely, if a point on the portion 46 of the rope is moved upwardly, the carrier will move downwardly along the stick. The second and third pulleys 37 and 39 project into the groove 42, as shown in Figure 2, and steady the carrier during its movement along the stick.

Referring now to Figures 4 and 5, the switch stick is arranged for use with a fuse on a disconnecting mounting as shown in Figure 5. The mounting consists of an insulating base 146 upon which are mounted upper and lower supports 47 and 48 respectively. A fuse member 4? is received between spring clamps 50, 51 on the upper and lower supports respectively. The fuse member is provided with flats 52 which are gripped by the spring clamps 50, 51. At its lower end, the fuse member is pro vided with a pair of transversely extending pivot pins 53, as shown in Figure 4, and the lower support 48 is provided with a pair of notched arms 54 adapted to receive the pivot pins 53, as shown in Figure 5. A loop 55 is provided at the upper end of the fuse member and a similar loop 56, see Figure 4, is provided at the lower end of the fuse member. A leaf spring 57 is mounted on the upper support 47 releasably to maintain the fuse member in operative position. The power line is arranged to be connected at 58 to the upper support 47 and the load line is arranged to be connected at 59 to the lower support 48.

In the full-line position shown in Figure 5, the fuse is in its operative position. If now the upper end of the fuse is pulled outwardly in the direction of the arrow X, the fuse member will pivot about the pivot pins 53 in the notched arms 54 and will fall to the position shown in phantom lines in Figure 5.

Heretofore, a common type of switch stick has consisted of a shaft with a knob, such as the knob 27, at one end of the stick. To disconnect the fuse from the position shown in Figure 5, with such a switch stick to replace the fuse, the knob has been fitted in the loop 55 and the fuse has been pulled outwardly in the direction of the arrow X and has been allowed to fall, controlled by the stick, to the position shown in phantom lines in Figure 5. The knob has then been disengaged from the loop and has been. engaged in the loop 56 at the lower end of the fuse member. The fuse member has then been lifted by the stick so that the pivot pins 53 are disengaged from the notches in the arms 54 and then the fuse member has been lowered. Similarly, to replace a fuse member, a fuse member has been lifted by the switch stick, by engaging the knob in the loop 56, until the pivot pins 53 are received in the notches of the arms 54 so that the fuse is then in the position shown in phantom lines in Figure 5. The knob of the switch stick has then been engaged in the loop 55 and the fuse member has been swivelled about its pivot pins to the position shown in full lines in Figure 5. As mentioned above, the fuse members weigh about 38 pounds and with switch sticks some fifteen feet long it is a very diflicult undertaking to lift the fuse member to engage the pins 53 in the notches in the arms 54.

The operation of the switch stick of the invention is shown in Figure 4. Assuming that there is no fuse member in the fuse mounting and that it is desired to replace a fuse member, the retroverted end 24 of the hook 23 is engaged with the clamp member 50 at the upper end of the fuse mounting so that the stick is supported from the clamp member.

The rope is' then moved to bring the carrier 34 towards the lower end of the stick and a fuse member is mounted on the hook 142. The hook 142 is passed through the loop 56 at the lower end of the fuse member so that the fuse member hangs upside down as shown in Figure 4. The rope is then operated to cause the carrier to ascend along the stick. It may be noted that the mechanicaladvantage of the pulley system is 2 and therefore considerably less force is required to elevate the fuse member than if no such pulley system were provided. The carrier is moved along the stick until the pivot pins 53 are slightly above the notched arms 54 of the fuse mounting assembly. The lower end of the switch stick is then swung in the direction of the arrow Y in Figure 4 to move the pivot pins over the notched arms 54 and then the fuse is lowered slightly to seat the pivot pins in the notches of the arms 54. The carrier is now lowered and the hook 142 disengaged from the loop 5.6. on the fuse member so that the fuse member will be left hanging in an inverted position from the lower support 48 of the mounting assembly.

The hook 24 of the switch stick is now unhooked from the clamp 50 and the knob 27 is inserted into the loop 55 at the upper end of the fuse member, which is hanging downwardly, and the fuse member is rotated in the direction of the arrow Z in Figure 5 until the flats 52 on the upper portion of the fuse member are received between the arms of the clamp 56. Simultaneously the flats 52 at the lower end of the fuse member are received between the arms of the clamp 51, thus completing the circuit. The knob 27 may then be removed from the loop 55 and the leaf spring 57 retains the fuse member in position.

To remove a fuse member the procedure is reversed. Starting from the position of the fuse member shown in full lines in Figure 5, the knob 27 on the switch stick is engaged in the loop 55 and the fuse member is swung downwardly to the position shown in phantom lines in Figure 5. The end 24 of the hook 23 is then engaged on an arm of the clamp 50 and the carrier 34 is raised by the rope until the hook 142 engages the loop 56 on the fuse member. The carrier is then raised slightly further to disengage the pivot pins 53 from the notches in the arms 54 on the lower support member and is then lowered to lower the fuse member. The fuse member is then unhooked from the hook 142 and is replaced by a fresh fuse member which is inserted in the fuse mounting in the manner hereinbefore described.

The method of operation of the switch stick according to the invention may be varied slightly by engaging the hook 23 on one of the arms of the clamp 51 on the lower support member.

It will be seen that the invention provides a simple switch stick whereby the effort involved in changing fuses in disconnecting mountings may be substantially reduced as compared with conventional switch sticks. In practice, the length of the switch stick will be arranged to conform with the heights of the fuse mountings at which it is going to be used.

It will be understood that the form of the invention herewith shown and described is a preferred example and that various modifications can be carried out without departing from the spirit of the invention or the scope of the appended claims.

What I claim as my invention is:

1. A switch stick including a carrier slidable along the stick, means operable from adjacent one end of the stick to slide the carrier along the stick, means on the carrier for releasably supporting a fuse member, and means adjacent to the other end of the stick to engage a fuse mounting to support the stick therefrom during movement of the carrier and the fuse member along the stick.

2. A switch stick having upper and lower ends, guide means adjacent to the upper end, a carrier slidable along the stick, means on the carrier for releasably supporting a fuse member, a flexible filament operatively connected to the carrier and passing upwardly from the carrier, over the guide means, and downwardly to adjacent to the lower end of the stick, and means adjacent to the upper end to engage a fuse mounting to support the stick therefrom during movement of the carrier and the fuse member along the stick.

3. A switch stick having upper and lower ends, a head at the upper end, a first pulley rotatably mounted in the head about an axis transverse of the stick, a carrier slidable along the stick, means on the carrier for releasably supporting a fuse member, pulley means on said carrier, a rope, an anchorage anchoring one end of the rope to the stick, the rope passing from the anchorage around said pulley means, upwardly over the first pulley and then downwardly to adjacent to the lower end of the stick, and means on the head to engage a fuse mounting to support the stick therefrom during movement of the carrier and the fuse member along the stick.

4. A switch stick having upper and lower ends, a head at the upper end, a first pulley rotatably mounted in the head about an axis transverse to the axis of the stick, a groove extending longitudinally of the stick, a carrier slidable along the stick, means on the carrier for releasably supporting a fuse member, a second pulley on the carrier, the second pulley projecting into said groove, a rope, an anchorage anchoring one end of the rope to the stick near the upper end thereof, the rope passing 6 from the anchorage along the groove, around the second pulley, upwardly and over the first pulley and then downwardly to a point adjacent to the lower end of the stick, and means on said head to engage a fuse mounting to support the stick therefrom during movement of the carrier and the fuse member along the stick.

5. A switch stick having upper and lower ends, a head at the upper end, a first pulley rotatably mounted on the head about an axis transverse to the axis of the stick, a groove extending longitudinally of the stick, a carrier slidable along the stick, means on the carrier for releasably supporting a fuse member, second and third pulleys on the carrier, said pulleys being rotatably mounted on axes parallel to the axis of the first pulley and projecting into said groove, a fourth pulley on the stick adjacent to the lower end thereof, the fourth pulley being rotatably mounted on an axis parallel to the axis of the other pulleys, a rope, a first anchorage anchoring one end of the rope near the upper end of the stick, the rope passing from the anchorage along the groove, around the second pulley, upwardly and over the first pulley, then downwardly and around the fourth pulley, then upwardly and around the third pulley, and finally downwardly along the groove, a second anchorage adjacent to the lower end of the stick, the other end of the rope being anchored in the second anchorage, and means on the head for engagement with a fuse mounting to support the stick therefrom during movement of the carrier and the fuse member along the stick.

6. A switch stick according to claim 5 wherein the means on the head for engagement of the fuse mounting is a hook with a retroverted end.

References Cited in the file of this patent UNITED STATES PATENTS 1,566,213 Hoberg Dec. 15, 1925 2,416,340 Moreland Feb. 25, 1947 2,428,186 Warwick Sept. 30, 1947 2,552,015 Quick May 8, 1951 FOREIGN PATENTS 348,685 Italy Mar. 25, 1937

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