Handle apparatus for a manual motor

Disclosed is a handle apparatus of a manual motor starter having an improved structure for transferring driving force between a control lever and a driving lever. The handle apparatus comprises: a rotary handle for controlling ON and OFF operations of the manual motor starter, an interlocking member coaxially coupled with the rotary handle to be rotated by rotation of the rotary handle, the interlocking member having a first gear for providing a driving force; a driving lever having a second gear formed at one side of the driving lever to be rotated by the driving force by the interlocking member, the driving lever having a pin slot for providing a rotational driving force; and a control lever having a sliding pin inserted in the pin slot of the driving lever, through which the rotational driving force is transferred from the driving lever to the control lever.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a handle apparatus for a manual motor starter, and more particularly to a handle apparatus of a manual motor starter, which has an improved structure for power transfer between a driving lever and a control lever of the starter, thereby minimizing the wear on parts of the starter and improving both the durability of the starter and the reliability in handle operation of the starter.

2. Description of the Prior Art

As is generally known in the art, a manual motor starter includes a detection part for detecting generation of accidental current, a switching mechanism operated when the generation of accidental current is detected, a contactors operated by the switching mechanism to switch on or off an electric path, an arc extinguishing mechanism for extinguishing and discharging an arc gas which may be generated when contactors are opened and a rotary handle1for manually operating the position of the starter to a ON position or OFF position.

FIG. 1is a perspective view of a conventional manual motor starter for protecting a motor, which includes a manual motor starter body (hereinafter, referred to as “MMS body”)100, a rotary handle1provided at the top of the MMS body100, and an Under Voltage Trip (hereinafter, referred to as “UVT”) mechanism provided at one side of the MMS body100.

When a user rotates the handle1to the ‘ON’ position in order to turn on the manual motor starter for starting a moter, the rotation of the handle1moves links of a switching mechanism in the MMS body100, causing a movable contactor to come into contact with a stationary contactor, so that electrical current flow between the contactors. In contrast, when the user rotates the handle1to the ‘OFF’ position, the links move to separate the contactors from each other, thereby interrupting the flow of electricity. In the manual motor starter having the construction as described above, an apparatus for transferring the rotational displacement of the handle1to accessory devices is necessary.

The UVT mechanism is one of various accessory devices of a manual motor starter (hereinafter, referred to as “MMS”) from accidents such as short-circuiting or motor overloads. The UVT mechanism trips the switching mechanism in the MMS body100when an under voltage below a rated voltage is applied to the MMS.

FIG. 2is a perspective view of a handle apparatus of a conventional MMS in a state where the MMS is turned off, andFIG. 3is a perspective view of a handle apparatus of a conventional MMS in a state where the MMS is turned on.

As shown inFIGS. 2 and 3, a handle apparatus of a conventional MMS includes a handle1for interrupting turn-on of the MMS, an interlocking assembly2connected to the handle1, a driving lever3operated by a driving gear3aengaged with an interlocking gear2aof the interlocking assembly2, and a control lever4rotated about a control lever rotation shaft5by the driving lever3.

The handle1can be rotated within an operation range between an “ON” operation and an “OFF” operation. The interlocking assembly2is rotated at the same angle as that of the handle1according to the rotation of the handle1. The interlocking assembly2has the interlocking gear2awhich is engaged with the driving gear3aof the driving lever3perpendicularly.

The driving lever3is rotated about a driving gear rotation shaft3caccording to the rotation of the interlocking assembly2. Specifically, the driving lever3has the driving gear3aformed at one side thereof, which is engaged with the interlocking gear2a, so that the driving lever3can be rotated according to rotation of the driving gear3aby the rotation of the interlocking assembly2. The driving lever3also has a protrusion3bformed at the other side of the driving lever3.

The control lever4has a crank hole4a formed through the control lever4. The crank hole4ahas hole circumferences4bformed at opposite ends of the crank hole4a, through which the protrusion3bof the driving lever3is inserted. Therefore, the control lever4can be rotated about the control lever rotation shaft5within a predetermined angular range by the rotation of the driving lever3.

According to the rotation of the handle1, the MMS performs an ‘ON’ operation for causing the switching mechanism to contact the movable contactor with the stationary contactor, thereby supplying current to a motor, or an ‘OFF ’operation for causing the switching mechanism to separate the movable contactor from the stationary contactor, thereby interrupting the supply of current to a motor.

The handle1is allowed to rotate within an angular range of 90° for the ‘ON’ and ‘OFF’ operations, and the control lever4connected to the handle1is allowed to rotate within an angular range of 47° for the ‘ON’ and ‘OFF’ operations.

In order to guarantee smooth operation of the control lever4following the operation of the handle1, the control lever4has the crank hole4aThe protrusion3bof the driving lever3is guided along the hole circumferences4bof the crank hole4awhile preventing play of the control lever4in an unexpected direction, thereby achieving a smooth rotation of the control lever4.

When the handle1of the MMS is at the OFF position as shown inFIG. 2, the protrusion3bof the driving lever3is located at the upper end of the crank hole4aof the control lever4. While the handle1of the MMS is rotated to the ON position as shown inFIG. 3, the protrusion3bof the driving lever3moves downward along the hole circumference4bof the crank hole4aand returns to its original position along the hole circumference4bof the crank hole4a.

However, in the handle apparatus of the conventional MMS having the construction as described above, the protrusion3bof the driving lever3made from synthetic resin is incontinuous contact with the hole circumferences4bof the crank hole4aof the control lever4made from metal while being moved by the rotation of the handle1. Therefore, the protuberance3bof the driving lever3made from synthetic resin may be easily worn out

Further, this problem (wearing of the protuberance3bof the driving lever3made from synthetic resin) may become more severe when the handle1is operated by an increased driving power or at a higher speed.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and an object of the present invention is to provide a handle apparatus for a manual motor starter, in which driving force is transferred by a sliding pin of a control lever made from metal, which is inserted through the pin slot formed through the driving lever made from synthetic resin, thereby solving the problem of the conventional MMS, in which the protrusion of the driving lever made from synthetic resin experience abrasion by circumferential surfaces of the crank hole of the control lever made from metal.

In order to accomplish this object, there is provided a handle apparatus for a manual motor starter, the handle apparatus comprising: a rotary handle for controlling ON and OFF operations of the manual motor starter, an interlocking member coaxially coupled with the rotary handle to be rotated by rotation of the rotary handle, the interlocking member having a first gear for providing a driving force; a driving lever having a second gear formed at one side of the driving lever to be rotated by the driving force by the interlocling member, the driving lever having a pin slot for providing a rotational driving force; and a control lever having a sliding pin inserted in the pin slot of the driving lever, through which the rotational driving force is transferred from the driving lever to the control lever.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 4A and 4Bare perspective views of a handle apparatus for an MMS according to the present invention in a state where the MMS is turned off, andFIGS. 5A and 5Bare perspective views of a handle apparatus for an MMS according to the present invention in a state where the MMS is turned on. Further,FIG. 6is a perspective view of a driving lever and a control lever of an MMS according to the present invention.

As shown inFIGS. 4 through 6, the handle apparatus for an MMS according to the present invention includes: a rotary handle11for controlling ON and OFF operations of the MMS; an interlocking member12coaxially coupled with the rotary handle11to be rotated by rotation of the rotary handle11, the interlocking member12having a first gear12afor providing a driving force; a driving lever13having a second gear13aformed at one side of the driving lever13to be rotated by the driving force by the interlocking member12, the driving lever13having a pin slot13bfor providing a rotational driving force; and a control lever14having a sliding pin14dinserted in the pin slot13bof the driving lever13, through which the rotational driving force is transferred from the driving lever13to the control lever14.

Referring toFIG. 6, the driving lever13also has a rotation shaft-holding boss13cthrough which a rotation shaft for the driving lever13is inserted. The rotation shaft-holding boss13cis integrally formed with a main body of the driving lever13and made from synthetic resin. Herein, the second gear13aof the driving lever13and the first gear12aof the interlocking member12are bevel gears meshed perpendicularly to each other. The driving lever13is rotated about a rotation shaft (not shown) inserted through the rotation shaft-holding boss13cby the driving force of the interlocking member12.

The control lever14, as clearly shown inFIG. 6, is a U-shaped member including two opposing side plates and a connecting portion for interconnecting the two side plates. In the following description, the two side plates will be referred to as a first control lever body14aand a second control lever body14b. The first control lever body14ahas the sliding pin14dinserted in the pin slot13bof the driving lever13, through which the rotational driving force is transferred from the driving lever13to the control lever14. The sliding pin14dis made from metal and especially has a slickly ground surface in order to minimize wearing of the driving lever13made from synthetic resin. The second control lever body14bis apart a predetermined interval from the first control lever body14a. A control lever rotation shaft15is fitted through lower portions of the first control lever body14aand the second control lever body14b. When the driving lever13is rotated, the rotation of the driving lever13is transferred through the circumference of the pin slot13bto the sliding pin14d, so that the control lever14is rotated a predetermined angle about the control lever rotation shaft15. Specifically, when the rotary handle11is rotated 90° from the ON position to the OFF position and vice versa, the control lever14is rotated the predetermined angle of 47°.

InFIG. 6, reference numeral14c not described above designates a spacing pin for spacing the first control lever body14aand the second control lever body14bof the control lever14a predetermined interval.

Hereinafter, on operation of a handle apparatus of an MMS having the aforementioned construction according to the present invention will be described. In order to turn on or off the MMS, a user may hold and rotate the rotary handle11between the ON position and the OFF position. Then, the rotary handle11rotates 90° clockwise or counterclockwise and the interlocking member12coaxially coupled with the rotary handle11also rotates 90° clockwise or counterclockwise. Then, the second gear13aperpendicularly engaged with the first gear12aof the interlocking member12rotates the driving lever1390° . The 90° rotation of the driving lever13is transferred to the sliding pin14dby circumferential surfaces of the pin slot13b, so that the control lever14rotates 47° about the control lever rotation shaft15. Here, when the rotary handle11of the MMS is located at the OFF position, the sliding pin14dof the control lever14is located at a lower position in the pin slot13bof the driving lever13as shown inFIG. 4B. In contrast, when the rotary handle11of the MMS is located at the ON position, the sliding pin14dof the control lever14is located at a middle position in the pin slot13bof the driving lever13as shown inFIG. 5B.

As described above, in the handle apparatus according to the present invention, driving force is transferred by the sliding pin14dof the control lever14made from metal, which is inserted through the pin slot13bformed through the driving lever13made from synthetic resin. As a result, the present invention can solve the problem of the conventional MMS, in which the protuberance3bof the driving lever3made from synthetic resin experience abrasion by circumferential surfaces of the crank hole4aof the control lever4made from metal. Therefore, the present invention can improve the durability of the MMS and the reliability in operating the MMS.