Title of Invention

"AN ENERGY STORING MECHANISM FOR A SWITCHGEAR"

Abstract

The present invention concerns an energy storing -mechanism for a switchgear, comprising: a main shaft having a closing cam connected with a contact closing lever for the switchgear and a crank portion connected with a closing spring the main shaft being driven to be rotated by an energy storing motor so as to store an energy in the closing spring through an operation of the crank portion and being rotated in the same direction as in storing the energy when the energy is released from the closing spring so as to move the contact closing lever through an operation of the closing cam, whereby a close operation of the switchgear is caused; an energy storing shaft disposed in parallel with the main shaft and supported by a supporting frame; a driving gear fitted on the energy storing shaft rotatably around the energy storing shaft and slidably along the energy storing shaft, the driving gear being driven to be rotated by the energy storing motor; and a transmitting gear fixed on the energy storing shaft to be close to the driving gear for transferring a rotation of the energy storing shaft to the main shaft, characterized in that an engaging means are disposed on opposing portions of the driving gear and the transmitting gear to engage each other when the driving gear is rotated by the energy storing motor; and a one-way clutch disposed on a supporting portion of the supporting frame where the energy storing shaft is supported, for constraining a rotation of the energy storing shaft in a reverse direction to the rotation for storing the energy. Representative Figure - Fig. 2

Full Text

TITLE OF THE INVENTION ENERGY STORING MECHANISM FOR SWITCHGEAR BACKGROUND OF THE INVENTION The present invention relates to a mechanism of storing an energy in a closing spring for causing a close operation of an electric switchgear such as a cutoff and a switchgear. In some of switchgears such as a cutoff, a stored energy of a spring is used for a close operation, more particularly, for making a movable contact element move toward a fixed contact element included in a main contact as rapidly as possible. In such a switchgear, the closing spring is constrained with an energy stored therein through compression or tension before conducting the close operation, and in the close operation, the stored energy of the closing spring released by releasing the constraint of the closing spring is used for moving a contact closing lever connected with the main contact, thereby rapidly moving the movable contact element. Various structures of an energy storing mechanism for storing an energy in the closing spring as well as a releasing mechanism have been proposed. FIG. 1 is a side sectional view of a main part of an energy storing mechanism disclosed in Japanese Patent Application Laid- Open No. 9-106741 (1997) filed by the present applicant. This energy storing mechanism includes a main shaft 1, an energy storing shaft 2 and an energy storing motor 3 supported substantially in parallel with one another by a common supporting frame 4. The main shaft 1 holds a gear wheel 10 at one end thereof projecting from one side of the supporting frame 4 and penetrates a closing cam 11 disposed at a middle thereof, so that the rotation of the main shaft 1 can axially rotate the gear wheel 10 and the closing cam 11. On the outer surface of the gear wheel 10, a crank pin 12 is disposed to be projected in a position away from the axial center of the main shaft 1 by an appropriate distance. The crank pin 12 is connected with one end of a presser rod 13, the other end of which is inserted through and supported by a spring plate 40. The spring plate 40 is a fixed plate integrally projected from, for example, the outside surface of the supporting frame 4. Between the spring plate 40 and the pressor plate 14 which is fixed at a middle of the pressor rod 13, a closing spring 5 is provided. As is shown in FIG. 1, when the crank pin 12 is positioned to be close to the spring plate 40 as a result of the rotation of the gear wheel 10, the closing spring 5 is compressed between the spring plate 40 and the pressor plate 14 so as to store an energy therein. This energy storing state of the closing spring 5 is retained by constraining the rotation of the gear wheel 10 with constraining means not shown. When the constraint is released, the spring force of the closing spring 5 is applied to the gear wheel 10 through the pressor plate 14, the pressor rod 13 and the crank pin 12, so that the main shaft 1 can be rotated at a high speed together with the gear wheel 10. Inside of the supporting frame 4, a contact closing lever 6 is disposed to be swingably supported by a supporting axis 60 projecting from one surface of the contact closing lever 6. On the other surface of .the contact closing lever 6, a roller 61 in contact with the circumferential cam surface of the closing cam 11 is supported, so that the contact closing lever 6 can swing around the supporting axis 60 in accordance with the rotation of the closing cam 11 through the movement of the roller 61 following the cam surface. The contact closing lever 6 is connected with a main contact not shown, so as to cause the close operation through the swing movement thereof. The energy storing shaft 2 is provided with a transmitting gear 20 integrally fixed on one end thereof projecting outward from one side of the supporting frame 4, and is also provided with a driving gear 21 movably set between the transmitting gear 20 and the outer surface of the supporting frame 4. The transmitting gear 20 is engaged with the gear wheel 10 fixed on the end of the main shaft 1, and the driving gear 21 is engaged with an output gear 30 fit on the output end of the energy storing motor 3. The energy storing motor 3 is a geared motor for obtaining a driving force of a motor body 3a through reduction by a speed reducer 3b connected at the output side of the motor body 3a. The output gear 30 is fit on an output axis 31 of the speed reducer 3b, and between the output axis 31 and a housing of the speed reducer'3b, a one-way clutch 7a for allowing the rotation in merely one direction is interposed. The driving gear 21 engaged with the output gear 30 is fit on the energy storing shaft 2 with a one-way clutch 7b and a claw clutch 8 fit and held in a hole penetrating the axial center of the driving gear 21, so as to be movable in a direction relative to the rotation direction of the energy storing shaft 2 and slidable in a direction along the energy storing shaft 2. The driving gear 21 is pressed toward the transmitting gear 20 by a energising spring 22 interposed between the outer surface of the supporting frame 4 and the driving gear 21. The one-way clutch 7b provided to the driving gear 21 allows the rotation in the same direction as that allowed by the oneway clutch 7a provided to the speed reducer 3b. The oneway clutch 7b transfers the rotation of the driving gear 21 brought from the output gear 30 to the claw clutch 8 disposed inside of the driving gear 21, and causes a slip against the rotation in the reverse direction brought from the claw clutch 8. The driving gear 21 is, in a general state, pressed toward the transmitting gear 20 by the force of the energising spring 22 in an elastic contact with one side thereof, so as to rotated together with the transmitting gear 20 through the engagement with the claw clutch 8. When the closing spring 5 is set in the energy storing state with the main shaft 1 and the gear wheel 10 positioned as is shown in FIG. 1, the driving gear 21 is pressed by a pressor projection 15 disposed on the surface of the gear wheel 10 other than the surface where the crank pin 12 is disposed so as to substantially oppose the crank pin 12 in the radial direction, and the driving gear 21 is moved away from the transmitting gear 20 against the spring force of the energising spring 22. Thus, the engagement between the driving gear 21 and the claw clutch 8 is released. In the conventional energy storing mechanism having the aforementioned structure, when the constraint of the gear wheel 10 is released in the state shown in FIG. 1, the stored energy of the closing spring 5 is released, so that the gear wheel 10 is rotated at a high speed in a predetermined direction. This rotation is transferred to the contact closing lever 6 through the closing cam 11, thereby swinging the contact closing lever 6 at a high speed. Thus, the main contact not shown is closed. In such a close operation, the rotation of the gear wheel 10 is transferred to the engaged transmitting gear 20 so as to rotate the energy storing shaft 2. The direction of the rotation thus caused is the direction in which the one-way clutch 7b disposed within the driving gear 21 causes a slip. Therefore, the driving gear 21 is not rotated, and the rotation is not transferred to the output axis 31 of the energy storing motor 3. The rotation of the gear wheel 10 caused by releasing the stored energy of the closing spring 5 continues due to its own inertia beyond a predetermined rotation position (a top dead center), during which the energy is stored in the closing spring 5. Therefore, the gear wheel 10 and the main shaft 1 are to be rotated in the reverse direction from a position beyond the top dead center. However, this reverse rotation is transferred to the oneway clutch 7b disposed within the driving gear 21 through the transmitting gear 20, so as to be transferred to the driving gear 21 through the engagement with the one-way clutch 7b. Furthermore, the rotation is transferred to the output axis 31 of the energy storing motor 3 through the output gear 30, and the one-way clutch 7a disposed on the output axis 31 is engaged. As a result, the reverse rotation is inhibited, so that the gear wheel 10 is constrained in the position beyond the top dead center. After attaining such a close state, the energy storing motor 3 is driven. The driving force is transferred to the driving gear 21 through the output gear 30 fit on the output axis 31, and is further transferred to the transmitting gear 20 through the claw clutch 8. As a result, the gear wheel 10 engaged with the transmitting gear 20 is rotated. Through this rotation, the pressor rod 13 connected with the clank pin 12 is pushed down, so as to compress the closing spring 5 between the pressor plate 14 and the spring plate 40. In this manner, the energy storing state as is shown in FIG. 1 is attained, and the energy storing mechanism is ready for a subsequent close operation. The rotation of the gear wheel 10 driven by the energy storing motor 3 is stopped when the pressor projection 15 pushes the driving gear 21 in a predetermined position so as to release the engagement of the claw clutch 8. This position is retained by constraining the gear wheel 10 by using the aforementioned constraining means. The conventional energy storing mechanism having the aforementioned structure includes the one-way clutch 7b and the claw clutch 8 combined with the driving gear 21. Therefore, the structure of the driving gear 21 is disadvantageously complicated. Furthermore, in order to inhibit the reverse rotation of the gear wheel 10 and the main shaft 1 from the top dead center, the one-way clutch 7a provided to the energy storing motor 3 is used. Therefore, the entire structure including that of the energy storing motor 3 is disadvantageously complicated. Moreover, in order to inhibit the reverse rotation of the gear wheel 10, it is necessary to make the claw clutch 8 engaged in a very short period of time after reaching the top dead center and before starting the reverse rotation. Therefore, it is necessary to improve the accuracy in the composing elements affecting the engagement of the claw clutch 8, such as variation of the rotation speed of the gear wheel 10 and a lubricating state between the claw clutch 8 and the energy storing shaft 2. BRIEF SUMMARY OF THE INVENTION The present invention was devised in view of the conventional disadvantages, and an object of the invention is providing an energy storing mechanism for a switchgear having high reliability which can be realized by a simple structure including a smaller number of composing elements and can definitely prevent a reverse rotation of a gear wheel and a main shaft in a close operation. The energy storing mechanism for a switchgear of this invention comprises engaging means disposed in opposing portions of a driving gear fit on an energy storing shaft and a transmitting gear for transferring a rotation to a main shaft for engaging the driving gear with the transmitting gear when the driving gear is driven to be rotated by an energy storing motor, and a one-way-clutch for constraining the reverse rotation disposed in a supporting portion for the energy storing shaft. Accordingly, when the gear wheel is rotated in a direction for closing a main contact beyond a top dead center and is to be rotated in a reverse direction, the one-way clutch disposed on a main frame is engaged with the energy storing shaft, so that the rotation of the energy storing shaft itself is constrained. Thus, the reverse rotation is inhibited. On the other hand, when the driving gear is driven by the energy storing motor, the engaging means disposed between the driving gear and the transmitting gear is engaged, so that the ransmitting gear and the energy storing shaft can be rotated in the direction allowed by the one-way clutch. As a result, an energy is stored in a closing spring through a crank portion provided on the gear wheel. Furthermore, in the energy storing mechanism of this invention, the engaging means is realized by first and second engagement teeth projected from the opposing surfaces of the driving gear and the transmitting gear respectively including first and second engagement faces rising substantially perpendicularly from the opposing surfaces and first and second slant faces continuous with the first and second engagement faces. Accordingly, through a contact between the first and second engagement teeth projected from the transmitting gear and the driving gear, the driving gear transfers a driving force of the energy storing motor to the transmitting gear, and through a slip between the slant faces of the first and second engagement teeth, the driving gear does not transfer the rotation of the transmitting gear to the energy storing motor. Alternatively, in the energy storing mechanism of this invention, the engaging means is realized by an engagement tooth provided on an opposing surface between the driving gear and the transmitting gear including an engagement face rising substantially perpendicularly from the opposing surface and a slant face continuous with the engagement face, and by an engagement projection penetrating the energy storing shaft so as to oppose the engagement tooth. Accordingly, through a contact between the engagement production, such as a pin projecting the energy storing shaft and the engagement face of the engagement tooth on the driving gear, the driving gear transfers a driving force of the energy storing motor to the transmission gear, and through a slip of the engagement pin on the slant face of the engagement tooth, the driving gear does not transfer the rotation of the transmitting gear to the energy storing motor. When the engagement tooth of the energy storing mechanism is manufactured integrally with the driving gear or the transmitting gear by cold forging, the engagement tooth can be obtained with high strength without requiring additional processing. The above and further objects and features of the invention will more fully be apparent from the following detailed description with accompanying drawings. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1 is a side sectional view for showing a main part of a conventional energy storing mechanism for a switchgear; FIG. 2 is a side sectional view for showing a main part of an energy storing mechanism for a switchgear according to the present invention; FIG. 3 illustrates the operation of a cutoff using the energy storing mechanism of the invention; FIG. 4 is a perspective view of a driving gear; FIGS. 5A and 5B are a front view and a side sectional view of the driving gear; FIG. 6 is a perspective view of a transmitting gear; FIGS. 7A and 7B are enlarged side view and side sectional view of the vicinity of the transmitting gear; and FIG. 8 is a perspective view of a transmitting gear used as another form of engaging means. DETAILED DESCRIPTION OF THE INVENTION The present invention will now be described with reference to the accompanying drawings illustrating an embodiment thereof. FIG. 2 is a side sectional view of a main part of an energy storing mechanism for a switchgear according to the invention, and FIG. 3 is a diagram for illustrating an operation of a cutoff using the energy storing mechanism of the invention. The energy storing mechanism of this invention includes, similarly to the conventional energy storing mechanism shown in FIG. 1, a main shaft 1, an energy storing shaft 2 and an energy storing motor 3 supported substantially in parallel with one another by a common supporting frame 4. The main shaft 1 holds a gear wheel 10 at one end thereof projecting from one side of the supporting frame 4 and penetrates a closing cam 11 disposed at a middle thereof, so that the gear wheel 10 and the closing cam 11 can be axially rotated in accordance with the rotation of the main shaft 1. On the outer surface of the gear wheel 10, a crank pin 12 is disposed to be projected in a position away from the axial center of the main shaft 1 by an appropriate distance. The crank pin 12 is connected with one end of a pressor rod 13, the other end of which is inserted through a spring plate 40. The spring plate 40 is a fixed plate integrally projected from, for example, the outside surface of the supporting frame 4. Between the spring plate 40 and a pressor plate 14 is fixed in the middle the pressor rod 13, a closing spring 5 is provided. When the crank pin 12 comes close to the spring plate 40 through the rotation of the gear wheel 10 as is shown in FIG. 2, the closing spring 5 is compressed between the spring plate 40 and the pressor plate 14 so as to store an energy. This energy storing state is retained by constraining the rotation of the gear wheel 10 by, as is shown in FIG. 3, engaging a pin 16 projected from an appropriate position on the outer surface of the gear wheel 10 with a closing latch 17. The constraint can be released by driving the closing latch 17 by using appropriate driving means so as to release the engagement with the pin 16. The spring force of the closing spring 5 attained at this point is applied to the gear wheel 10 through the pressor plate 14, the pressor rod 13 and the crank pin 12, so that the gear wheel 10 and the main shaft 1 make a 1/2 revolution in the clockwise direction in FIG. 3 at a high speed. Inside of the supporting frame 4, a contact closing lever 6 is supported to be swingable by a supporting axis 60 projected from one surface thereof. On the other surface of the contact closing lever 6, a roller 61 in contact with the circumferential cam surface of the closing cam 11 is supported, so that the contact closing lever 6 can swing around the supporting axis 60 in accordance with the rotation of the closing cam 11 caused by the movement of the roller 61 following the cam surface. The closing cam 11 has, as is shown in FIG. 3, the cam surface with a distance from the axial center of the main shaft 1 increasing in accordance with the clockwise rotation caused by releasing the closing spring 5. The swing movement of the contact closing lever 6 brought by releasing the closing spring 5 is caused in the counterclockwise direction in FIG. 3. On the other surface of the contact closing lever 6, pins 62 and 63 are projected at both sides of the supporting axis 60, and the pin 62 at one side is connected with a main contact 9 through a link 90, so that a close operation can be caused by the swing movement of the contact closing lever 6 brought by releasing the closing spring 5. The other pin 63 is engaged with a tripping latch 64 so as to constrain the swing movement of the contact closing lever 6 when the contact closing lever 6 is swung to attain the close state of the main contact 9. When the tripping latch 64 is driven by using appropriate driving means so as to release the engagement with the pin 63, a movable contact element is taken off from the main contact 9 by a spring force of a tripping spring 91 included in the main contact 9. Thus, the main contact 9 is opened. A reference numeral 92 shown in FIG. 3 denotes a contact pressure spring for retaining a contact pressure between a fixed contact element of the main contact 9 and the movable contact element in the closed state. Also, the energy storing shaft 2 is provided with a transmitting gear 20 integrally fixed on one end thereof projecting from one side of the supporting frame 4 and a driving gear 21 movably set between the transmitting gear 20 and the outer surface of the supporting frame 4, and a clutch 7 is provided to a supporting portion on the wall of the supporting frame 4 where the energy storing shaft 2 is supported. The transmitting gear 20 is engaged with the gear wheel 10 fixed on one end of the main shaft 1, and the driving gear 21 is engaged with an output gear 30 fit on the output end of the energy storing motor 3. The energy storing motor 3 is a geared motor for obtaining a driving force of a motor body 3a through reduction by a speed reducer 3b connected with the output side of the motor body 3a. The output gear 30 is fit on an output axis 31 of the speed reducer 3b. FIG. 4 is a perspective view of the driving gear 21 engaged with the output gear 30, FIG. 5A is a front view of the driving gear 21, and FIG. 5B is a side sectional view of the driving gear 21. As is shown in these drawings, the driving gear 21 has a supporting hole 21a penetrating the axial center thereof and an engagement hole 21b formed at one side of the supporting hole 21a and having a larger diameter than the supporting hole 21a. The engagement hole 21b is provided with two first engagement tooth 21c disposed in two positions in the peripheral direction, each including a first engagement face 21d rising substantially perpendicularly from a bottom face 24 opposing the transmitting gear 20 and a first slant face continuous between the engagement face 21d and the bottom face 24 in the peripheral direction with an appropriate inclination against the bottom face 24. The driving gear 21 having such a structure is fit on the energy storing shaft 2 with the opening of the engagement hole 21b including the engagement tooth 21c opposing the transmitting gear 20, so as to be movable in a direction relative to the rotation direction of the energy storing shaft 2 and slidable in a direction along the energy storing shaft 2 through the supporting hole 21a. Also, the driving gear 21 is pressed toward the transmitting gear 20 by a energising spring 22 as ,a energising spring interposed between the outer surface of the supporting frame 4 and the driving gear 21. FIG. 6 is a perspective view of the transmitting gear 20 integrally provided on the end of the energy storing shaft 2, FIG. 7A is an enlarged side view of the vicinity of the transmitting gear 20, and FIG. 7B is a sectional view taken on line B-B of FIG. 7A. As is shown in these drawings, an end face 25 at the end of the transmitting gear 20 opposing the driving gear 21 is provided with two second engagement tooth 20c disposed in two positions in the peripheral direction, each including a second engagement face 20a rising substantially perpendicularly from the end face 25 and a second slant face continuous between the engagement face 20a and the end face 25 with an appropriate inclination against the end face 25. The angle and the direction of the inclination against the end face 25 of the second tooth 20c is substantially the same as those against the bottom face 24 of the first engagement tooth 21c. Therefore, when the transmitting gear 20 is disposed to oppose the driving gear 21 as is shown in FIG. 2, the first and second engagement teeth 21c and 20c oppose each other with the inclinations in the reverse directions. The present invention is characterized by the thus obtained engaging means. When the driving gear 21 is rotated in one direction relatively to the transmission gear 20, the engaging means makes the transmitting gear 20 engaged with the driving gear 21 with the engagement faces of the engagement teeth 20c and 21c in contact with each other. Thus, the driving gear 21 and the transmitting gear 20 can be integrally rotated. On the other hand, when the transmission gear 20 is rotated in the same direction relatively to the driving gear 21, the engaging means allows the rotation of the transmission gear 20 by causing a slip between the slant faces of the engagement teeth 20c and 21c. Thus, the driving gear 21 can be retained unmoved. The engagement by the engaging means is caused in the rotation of the driving gear 21 driven by the energy storing motor 3. Also, the one-way clutch 7 disposed on the supporting portion for the energy storing shaft 2 on the wall of the supporting frame 4 allows the rotation in the direction for causing the engagement and constrains the rotation in the reverse direction. The driving gear 21 is, in a general state, pressed toward the transmitting gear 20 by the spring force of the energising spring 22 in an elastic contact with one side thereof. This pressure applied by the energising spring 22 is released as follows: When the closing spring 5 is in the energy storing state with the main shaft and the gear wheel 10 positioned as is shown in FIGS. 2 and 3, the driving gear 21 is pressed by a pressor projection 15 disposed on the surface of the gear wheel 10 other than the surface where the crank pin 12 is provided so as to substantially oppose the crank pin 12 in the radial direction, and the driving gear 21 moves away from the transmitting gear 20 against the spring force of the energising spring 22. In the energy storing mechanism of the invention having the aforementioned structure, when the constraint of the gear wheel 10 is released by driving the closing latch 17 from the state shown in FIGS. 2 and 3, the stored energy of the closing spring 5 is released, so that the gear wheel 10 can be rotated as described above. The rotation is transferred to the contact closing lever 6 through the closing cam 11, so as to swing the contact closing lever 6 at a high speed. As a result, the main contact 9 is closed by the movement of the link 90 connected with the pin 62. In such a close operation, the rotation of the gear wheel 10 is transferred to the engaged transmitting gear 20 so as to rotate the energy storing shaft 2. The rotation direction at this point is the direction allowed by the one-way clutch 7 disposed on the supporting portion for the energy storing shaft 2 as well as the direction for the engaging means to cause a slip. Therefore, the driving gear 21 fit on the energy storing shaft 2 can be retained unmoved, and the rotation is not transferred to the output axis 31 of the energy storing motor 3. The rotation of the gear wheel 10 brought by releasing the closing spring 5 continues due to its own inertia beyond a predetermined rotation position (a top dead center), during which the energy is stored in the closing spring 5. Therefore, the gear wheel 10 and the main shaft 1 are to be rotated in the reverse direction from a position beyond the top dead center, and this rotation is transferred to the energy storing shaft 2 through the transmitting gear 20. However, this reverse rotation direction is the direction for causing the constraint by the one-way clutch 7 disposed on the supporting portion for the energy storing shaft 2, and hence, the reverse rotation is inhibited by the engagement of the one-way clutch 7. Thus, the gear wheel 10 is constrained in the position beyond the top dead center. After attaining such a closed state, the energy storing motor 3 is driven. This driving force is transferred to the driving gear 21 through the output gear 30. The direction of this rotation is the direction for the engaging means to cause the engagement as well as the direction allowed by the one-way clutch 7 disposed on the supporting portion for the energy storing shaft 2. Therefore, the rotation of the driving gear 21 is transferred to the transmitting gear 20, so as to rotate the transmitting gear 20 and the energy storing shaft 2. As a result, the gear wheel 10 engaged with the transmitting gear 20 is rotated. Through this rotation, the pressor rod 13 connected with the crank pin 12 is pressed down, so as to compress the closing spring 5 between the pressor plate 14 and the spring plate 40. Thus, the energy storing state as is shown in FIG. 2 can be attained, and the energy storing mechanism is ready for a subsequent close operation. The rotation of the gear wheel 10 driven by the energy storing motor 3 is automatically stopped when the pressor projection 15 pushes the driving gear 21 so as to release the engagement of the engaging means provided between the transmitting gear 20 and the driving gear 21. The rotation position at this point is retained through the constraint of the gear wheel 10 by the engagement of the closing latch 17 with the pin 16. In this manner, the energy storing mechanism of this invention can attain the same operation as that of the conventional mechanism by using a more simple structure including the engaging means provided between the opposing surfaces of the transmitting gear 20 and the driving gear 21 and the one-way clutch 7 disposed on the supporting portion for the energy storing shaft 2. Also, the operation of the one-way clutch 7 for inhibiting the reverse rotation of the gear wheel 10 and the main shaft 1 can be conducted independently regardless of the engagement state of the engaging means. Accordingly, the reverse rotation can be definitely inhibited without improving the accuracy of the respective composing elements. Moreover, the engagement teeth 20c and 21c included in the engaging means have the simple structures as is shown in FIGS. 4 through 7A and 7B, and there is no need to attain accuracy in their shapes. Therefore, these elements can be integrally manufactured with the transmitting gear 20 and the driving gear 21 by cold forging. Thus, the composing elements can be manufactured with a high strength through a smaller number of procedures, and their reliability can be improved. The engaging means is not limited to the engagement teeth 20c and 21c provided on the transmitting gear 20 and the driving gear 21 but can be attained in another form. FIG. 8 is a perspective view of a transmitting gear 20 adoptable as another form of the engaging means. In the form of FIG. 8, an engagement pin 23 as a projection is provided to penetrate through the energy storing shaft 2 in the radial direction in a position close to the transmitting gear 20 fixed on the end of the energy storing shaft 2. The projections of the engagement pin 23 are brought to a contact with the engagement faces 21d of the engagement teeth 21c on the driving gear 21 as is shown in FIGS. 4, 5A and 5B, resulting in attaining the engagement between the driving gear 21 and the transmitting gear 20. Furthermore, the engagement can be released by the projections of the engagement pin 23 slipping along the slant faces of the engagement teeth 21c. As described in detail so far, in the energy storing mechanism for a switchgear of this invention, the engaging means to be engaged during the rotation brought by the energy storing motor is disposed in the opposing portion between the driving gear fit on the energy storing shaft and the transmitting gear for transferring the rotation to the main shaft, and the one-way clutch for constraining the reverse rotation is disposed on the supporting portion for the energy storing shaft. Accordingly, the reverse rotation of the gear wheel and the main shaft can be definitely inhibited in the close operation by adopting the simple structure including a smaller number of composing elements. Also, the engaging means is constituted by the engagement tooth including the engagement faces rising perpendicularly from the opposing faces of the driving gear and the transmitting gear and the slant faces continuous with the engagement faces. Alternatively, the engaging means is constituted by the similar engagement tooth provided on the opposing face of the driving means and the engagement pin penetrating the energy storing shaft so as to oppose the engagement tooth. Therefore, the engagement can be definitely brought or released. Furthermore, the engagement teeth can be manufactured integrally with the driving gear or the transmitting gear by cold forging, and hence, the engagement teeth can be manufactured with a high strength without increasing a number of procedures. As this invention may be embodied in several forms without departing from the spirit of essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within metes and bounds of the claims, or equivalence of such metes and bounds thereof are therefore intended to be embraced by the claims. We claim: 1. An energy storing mechanism for a switchgear, comprising: a main shaft including a closing cam connected with a contact closing lever for the switchgear and a crank portion connected with a closing spring, the main shaft being driven to be rotated by an energy storing motor so as to store an energy in the closing spring through an operation of the crank portion, and being rotated in the same direction as in storing the energy when the energy is released from the closing spring so as to move the contact closing lever through an operation of the closing cam, whereby a close operation of the switchgear is caused; an energy storing shaft disposed in parallel with the main shaft and supported by a supporting frame; a driving gear fit on the energy storing shaft rotatably around the energy storing shaft and slidably along the energy storing shaft, the driving gear being driven to be rotated by the energy storing motor; and a transmitting gear fixed on the energy storing shaft to be close to and oppose the driving gear, for transferring a rotation of the energy storing shaft to the main shaft, characterized by including: engaging means disposed on opposing portions of the driving gear and the transmitting gear to be engaged each other when the driving gear is rotated by the energy storing motor; and a one-way clutch disposed on a supporting portion of the supporting frame where the energy storing shaft is supported, for constraining a rotation of the energy storing shaft in a reverse direction to the rotation for storing the energy. 2. The energy storing mechanism according to claim 1, wherein said engaging means includes: a first engagement tooth projected from a first opposing surface of the driving gear opposing the transmitting gear, the first engagement tooth including a first engagement face rising substantially perpendicularly from the first opposing surface and a first slant face continuous between the first engagement face and the first opposing surface with an inclination against the first opposing surface; a second engagement tooth projected from a second opposing surface of the transmitting gear opposing the driving gear, the second engagement tooth including a second engagement face rising substantially perpendicularly from the second opposing surface and a second slant face continuous between the second engagement face and the second opposing surface with an inclination against the second opposing surface, the second slant face having substantially the same inclination in substantially the same direction as the first slant face; and a energising spring for energising the driving gear toward the transmitting gear, wherein the first and second engagement teeth are disposed in a manner that the first engagement face comes in contact with the second engagement face when the energy storing motor is driven. 3. The energy storing mechanism according to claim 1, wherein the engagement means includes: an engagement tooth projected from an opposing surface of the driving gear opposing the transmitting gear, the engagement tooth including an engagement face rising substantially perpendicularly from the opposing surface and a slant face continuous between the engagement face and the opposing surface with an inclination against the opposing surface; an engagement projection projecting the energy storing shaft in a radial direction in a position between the driving gear and the transmitting gear; and a energising spring for energising the driving gear toward the transmitting gear, wherein the engagement tooth is disposed in a manner that the engagement face comes in contact with the engagement projection when the energy storing motor is driven. 4. The energy storing mechanism according to claim 2, wherein the first engagement tooth is manufactured integrally with the driving gear by cold forging, and the second engagement tooth is manufactured integrally with the transmitting gear by cold forging. 5. The energy storing mechanism according to claim 3, wherein the engagement tooth is manufactured integrally with the driving gear by cold forging. 6. An energy storing mechanism for a switchgear substantially as hereinbefore described with reference to and as Illustrated In the accompanying drawings.

Documents:

2012-del-1998-abstact.pdf

2012-del-1998-claims.pdf

2012-del-1998-correspondence-others.pdf

2012-del-1998-correspondence-po.pdf

2012-del-1998-description (complete).pdf

2012-del-1998-drawings.pdf

2012-del-1998-form-1.pdf

2012-del-1998-form-13.pdf

2012-del-1998-form-19.pdf

2012-del-1998-form-2.pdf

2012-del-1998-form-3.pdf

2012-del-1998-form-4.pdf

2012-del-1998-form-6.pdf

2012-del-1998-gpa.pdf

2012-del-1998-petition-137.pdf

2012-del-1998-petition-138.pdf

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