CN1175453C - Switch operating shaft unit - Google Patents

Abstract

The invention relates to a switch-operating lever unit for switches, comprising a switch-operating lever body (2) on which a contact lever (3) is mounted. Caps (8) for covering and mounting the switch-operating lever body (2) are arranged at two opposite ends of said body (2). The unit can further comprise a tensioning device which can act on the contact lever and is positioned either outside the space housing the contact lever and within the switch-operating lever body or is covered and mounted on the switch-operating lever body (2).

Description

Switch operating shaft unit

technical field

The invention relates to an actuating shaft unit of a switch having an actuating shaft and a contact lever mounted on the actuating shaft, in particular to an actuating shaft unit incorporated in a low-voltage switch.

Background technique

European patent EP 0560 697 B1 discloses this operating shaft unit, which constitutes a cylindrical operating shaft with a radially extending through hole, in addition to an S-shaped contact rod, an S-shaped contact rod is also housed in the hole. A spring-equipped tensioning device acting on the rod. The actuating shaft unit configured in this way is mounted rotatably in the housing of the circuit breaker by means of the cylindrical peripheral surface of the actuating shaft.

Another European patent EP 0314 540 B1 discloses an operating shaft unit of similar structure, which differs from the operating shaft unit described in EP 0560 697 B1 only in the special structure of the tensioning device.

Contents of the invention

The present invention aims at proposing an operating shaft unit which has a long life and is less damaged by electric discharges due to short circuits generated in the operating space.

The technical solution to this object consists in an operating shaft unit of a switch having an operating shaft and a contact lever supported on the operating shaft, characterized by end shields covering opposite sides of the operating shaft, The end shield is used to rotatably mount the operating shaft unit of the switch.

In the case of this structure, the bearing friction caused by the function of the operating shaft unit is limited to certain sections. In addition, due to the special position of these sections on the operating shaft body, the contact space caused by short circuits It is quite difficult to corrode them by electric discharge.

In one embodiment of the actuating shaft unit, the contact lever can be acted upon by a tensioning device arranged approximately on opposite sides of the actuating shaft body and covered by end caps. The tensioning device is therefore located in an area protected by the end shield, but outside the cutout of the operating shaft body in which the contact rod is mounted and which is corroded by electrical discharges caused by the short circuit. In this arrangement, the moving parts of the tensioning device are substantially protected, so that operationally induced influences hardly impair the function of the actuating shaft unit.

According to one embodiment of the actuating spindle unit, the end shield is positively connected to opposite sides of the actuating shaft by means of two diametrically opposite parts. This construction ensures quick and reliable installation of the endshield. The projections formed on the inside of the end shield can be used, for example, as opposing parts which engage with recesses arranged on opposite sides of the actuating shaft. In this case, the recess therein is preferably formed as a through-hole arranged in the actuating shaft body, which at the same time can be used for accommodating an actuating pin of the actuating shaft body. In this way, a plurality of operating shaft units arranged parallel to each other can be operated by a single rod-shaped pin passing through the operating shaft body.

In the operating shaft unit of the present invention, the tensioning device mainly composed of two springs is preferably placed in two groove-shaped grooves, which are arranged radially and parallel to each other on both sides of the operating shaft body. extend. These two recesses simultaneously form engagement sections for correspondingly provided projections on the inner side of the end shield. The orientation of the grooves is preferably selected such that the direction of extension of any groove forms an included angle of 20° to 70° with the interconnection line of the diametrically opposite meshing segments formed on the operating shaft.

In another embodiment of the operating shaft unit, the part provided for establishing the positive connection between the operating shaft body and the end shield comprises several projections, which are formed on opposite sides of the operating shaft body and Interengages with cutouts provided in the disc-shaped end shield. These cutouts are preferably formed as U-shaped cutouts in the disk-shaped end shield, and from the bottom of the U-shaped cutouts project rib-shaped projections which engage corresponding groove-shaped recesses in the operating shaft body.

In another structure of the operating shaft, each end shield preferably has two cross-shaped grooves on its corresponding side facing the inner side of the operating shaft, so that one of the grooves can always be aligned with the operating shaft. The grooved grooves on the shaft body overlap regardless of the mounting side of the endshield.

In all designs of the actuating shaft unit, each end shield preferably has on its outer side a journal for supporting the actuating shaft unit, and the diameter of this journal is considerably smaller than the diameter forming the cylindrical actuating shaft body. This largely eliminates the risk of damage to the bearings of the actuating shaft unit due to electrical discharges in the contact chamber of the switch and at the same time minimizes the friction of the bearings.

Another combination scheme to realize the purpose of the present invention is that it can also be realized by such an operating shaft unit, that is, the tensioning device is concealedly arranged outside the space where the contact rod is installed inside the operating shaft body. In special cases, the tensioning device Concealed placement is again achieved by a detachable end shield on the operating shaft.

The present invention will be described in detail below in conjunction with two embodiments shown in the accompanying drawings.

Description of drawings

Fig. 1 is a partial sectional view of the housing of the low-voltage switch arc extinguishing device equipped with the operating shaft unit of the present invention;

Figure 2 shows the operating shaft unit shown in Figure 1 when the switch is in the OFF state;

Fig. 3a is a partial perspective exploded view of the first structural form of the operating shaft unit of the present invention;

Figure 3b is a perspective exploded view of the operating shaft unit in Figure 3a in a partially assembled state;

Fig. 4a is a partial perspective exploded view of the second structure of the operating shaft unit of the present invention;

Fig. 4b Fig. 4a is a perspective exploded view of the operating shaft unit in a partially assembled state.

Detailed ways

The low-voltage switch not shown in detail in Fig. 1 has an arc extinguishing device which consists of a housing 11, an operating shaft unit 9 housed in the housing, an arc extinguishing chamber, conductors 16 and some improved extinguishing devices. other parts of the arc. The housing 11 of the arc quenching device is installed in a housing (not shown in detail) of the low-voltage switch. The operating shaft unit 9 serves to establish an electrical connection between the two electrical conductors 16 .

The actuating shaft unit 9 essentially consists of a cylindrical actuating shaft body 2 on which is supported an S-shaped contact rod 3 which can be rotated by means of a bearing shaft 5 mounted in the shaft body. The entire actuating shaft unit 9 is mounted rotatably in a not-shown bearing section of the housing 11 . This special support method will be described in detail below in connection with the structural description of the operating shaft unit.

The operating shaft unit 9 can be operated with a hinged rod 10 to make the switch reach the closing state shown in FIG. 1 or the opening state shown in FIG. 2 .

As shown in detail in FIG. 3 a , the operating shaft unit 9 consists of a rotationally symmetrical, approximately cylindrical operating shaft body 2 .

The axis of the cylindrical actuating shaft 2 coincides with the geometrical axis of the bearing shaft 5 on which the contact lever 3 is rotatably mounted. The contact lever 3 is mounted in a groove 2e extending perpendicularly to the axis of the actuating shaft 2 and passing through the actuating shaft 2 radially.

Grooves 2c extending radially and parallel to each other and forming grooves are provided on both end faces of the cylindrical operating shaft body 2 . A U-shaped groove 2d is inserted in the wall between the middle groove 2e and the bottom section of the corresponding groove 2c at both ends of the groove 2c for mounting the pin 6 . On each pin 6 is substantially centrally rotatably supported a roller 6a which is slidably fitted in the groove 2e. The spring 7 is installed in the groove 2c, and its two ends hang on the end of the clamping pin on each end surface of the operation shaft body 2. Compared with the width of the central support section of the S-shaped contact rod 3, the length of the groove 2d is determined such that the pin 6 does not allow to be pulled tight against the bottom of the U-shaped groove 2d, regardless of the operating state of the switch. Rotation of the operating shaft 2 causes the roller 6a of the pin 6 to roll away from the always tight top of the S-shaped contact rod 3 and to be pressed out of the groove 2d in the opposite direction of the force of the spring 7 which tightens the clamping pin 6 , so that a permanent tension force acts on the contact rod 3 in the counterclockwise direction.

In addition, the operating shaft body 2 has another mounting hole 2b in which a rod pin 1 is mounted. On both end faces of the operating shaft body 2, U-shaped cutouts 2a are provided radially opposite to the mounting holes 2b.

The end shield 8 is arranged on the cylindrical operating shaft body 2 . Each end cap 8 has a circumferentially cylindrical collar section 8e, on the inside of which a pair of substantially radially extending reinforcing ribs 8c and an independent U-shaped rib section 8a are arranged. The reinforcing ribs also contribute to the increase of creepage distances and air gaps in the switch interrupter.

Between the reinforcing ribs 8c of each end shield 8 a recess 8i is formed, which extends along the inner side of the end shield 8 . The end shield is positioned on the operating shaft body 2 during installation in such a way that the grooves 8i are located in the same plane as the grooves 2d of the operating shaft body 2 and support the ends of the pins 6, respectively. In this arrangement, therefore, the recess 8i acting as an axial limit for the pins 6 guides the pins 6 as they move in the slot 2d due to operation, thus avoiding in an efficient manner the Possible tilt of the pin in 2d.

When the corresponding end cap 8 is mounted on the corresponding end face of the operating shaft body 2 , the segments 8 c and 8 a form a positive connection with the grooved recess 2 c and the U-shaped cutout 2 a formed on the edge of the operating shaft body 2 .

Furthermore, the end shield 8 has a bore which is formed by a cylindrical section 8b extending on the inside of the end shield. The cylindrical section 8b is located diametrically opposite the projecting U-shaped ribbed section 8a and has an outer diameter which approximately corresponds to the inner diameter of the mounting hole 2b formed in the actuating shaft body 2 . The angle between the connecting line of the midpoint of the cylinder section 8b and the midpoint of the U-shaped ribbed section 8a and an imaginary straight line drawn between the rounded rib 8c is equal to the connecting line of the otch 2a and the support hole 2b and the concave The angle formed between the centerlines of the grooves 2c. In principle, this angle is between 20° and 70°, preferably approximately 65°.

On the outside of an end cover 8, a pin-shaped journal 8d is provided behind the U-shaped ribbed section 8a on the opposite side to the hole radial direction of the cylinder section 8b, and this journal 8d plays the role of a mounting support, so that The actuating shaft 2 is correctly mounted in the housing 11 of the switch, not shown in detail.

Each end cap 8 is provided on its outer side with a journal 8f for axially supporting the actuating shaft unit 9 in a not shown bearing section of the switch housing 11 . On the end face outer surface of each end shield there are two diametrically opposite bores 8g which are used for depressurizing the actuating shaft body 2 . One of the end shields 8 has a protruding section 8b on its collar section 8e, which simultaneously serves as a mark for the correct installation position of the end shield and the groove 2d of the operating shaft body 2 and the circumferential side of the roller 6a .

When installing the operating shaft unit 9, the contact rod 3 is first fitted into the groove 2e of the operating shaft body 2 in such a way that the pin 5 used as a hinge shaft passes through one of the operating shaft body 2 and the contact rod 3 from the outside, not shown in detail. the support hole. Then insert the pin 6 in the groove 2d and hang the spring 7 on both sides of the pin end operating shaft body with a slight tension on it. Immediately afterwards, the two end covers 8 are first pressed onto the two sides of the operating shaft body 2 until the U-shaped rib section 8a, reinforcing rib 8c and cylindrical section 8b provided on the inner side of the end cover are respectively inserted into the U-shaped notch 2a and the groove-shaped Groove 2c and bearing hole 2b. The end shield 8 is preferably made of plastic, so that the protruding sections 8a, 8c and 8b arranged on the inside of the end shield can be fitted to both sides of the operating shaft body 2 under a slight pressure, so no additional tools are needed. The end cover can then be fixed to the operating shaft body.

Then the operating shaft unit 9 assembled in this way is arranged in the housing 11 of the arc extinguishing device in the installation section not shown in detail in FIG. In the corresponding contour of the plain bearing segment with mounting segment. The articulated rod 10 shown in Figure 1 is then mounted on an outside of the housing 11 in such a way that the bar-shaped pin 1 is embedded in a hole formed at the lower end of the articulated rod 10 and one of a cylindrical section 8b of the end shield 8 is connected to the The holes are aligned in a straight line.

Figures 4a and 4b show another structural form of the operating shaft unit 9 of the present invention, which differs from the first structural form shown in Figures 3a and 3b mainly in the structure of the operating shaft body and the end face of the end shield.

The actuating shaft 22 shown in FIGS. 4 a and 4 b has a cutout 22 e extending perpendicularly to the axis of the actuating shaft, in which a contact lever 23 with a contact element 24 is accommodated. In the same manner as in the first structural form, the protruding cylindrical section 26a of the pin 26 is in contact with the top surface of the S-shaped contact rod 23, so that when the operating shaft body 22 rotates in the counterclockwise direction, it will contact the contact rod. An elastic pressure acts on the contact rod in the through position, as shown in Figure 1. This principle of action has already been explained in the first design.

On each end face of the actuating shaft body 22 are formed two substantially rectangular projections 22 a , 22 b which lie opposite each other in the radial direction. The protrusions 22b formed on the two end faces of the operating shaft body 22 form the outlet of a hole segment that is arranged in the operating shaft body 22 and are used to install a rod-shaped pin shaft 21, while the radially opposite The raised portion 22a is provided with only the hole 22g. A radially extending groove-shaped recess 22c for receiving a spring 27 is formed between the projections 22a and 22b. A slit-shaped recess 22f is provided in the end surface of the operating shaft body 22 along opposite sides of the protrusions 22a, 22b.

Disc-shaped end shields 28 made of flat materials are provided on both sides of the operating shaft body 22 . The end cover 28 has a substantially flat disc shape, and two diametrically opposed cutouts 28a, 28b are provided on the disc, so that the protrusions 22a arranged on the two ends of the operating shaft body 22 when the end cover is installed , 22b engage in these two cutouts. The U-shaped cutouts 28a, 28b have at their bottom a section 28c that is bent towards the side where the end cover 28 is installed, and its length is consistent with the width of the cutouts 28a, 28b. The end face can be inserted into the slot-shaped recess 22f and at the same time contributes to increasing the creepage distance and the air gap in the switch.

In addition, each inner surface of the end cover 28 corresponding to one end surface of the operating shaft body 22 is provided with an X-shaped groove 28e, which is used to install the spring 27 protruding from the end surface of the operating shaft body. One section, regardless of the end face on which the endshield is installed. Such a configuration of the groove 28 e allows interchangeability of the end shields 28 mounted on both sides of the operating shaft body 22 . As shown in Figure 4b, the diameter of the disc-shaped end cover 28 is consistent with the diameter of the cylindrical operating shaft body 22, so in the state of completion, the edge of the end cover 28 is consistent with the cylindrical peripheral surface of the operating shaft body 22 flush.

Arranged on the outside of each end shield 28 is a journal 28f with which the actuating shaft unit is rotatably mounted in a correspondingly formed bearing section of the housing 11 , not shown in detail in FIG. 1 .

Due to the structure of the actuating shaft unit shown in detail above, a structurally simple mounting of the actuating shaft unit in the switch housing is ensured, and at the same time reliable protection of the moving parts of the actuating shaft against spark discharges is ensured. Furthermore, creepage distances and air gaps from contact rod 3, spring 7 and pin 6 to bar pin 1 are increased. In the case of a single-pole switch, the rod-shaped pin is connected to a transmission mechanism not shown in the figure and the operating shaft unit, while in the case of a multi-pole switch, the rod-shaped pin is connected to the transmission mechanism and the operating shaft unit, and Interconnect these operating shaft units themselves. The structure of the end shield ensures its reliable connection with the operating shaft. In this way, it is difficult for gas generated during a short circuit to enter the moving part of the switch and the operating shaft unit, and reliable shielding with adjacent switch units is ensured.

Incorrect installation of the end shields is impossible, since the end shields are either clearly distinguishable from each other in appearance and thus can be arranged on the prescribed side of the operating shaft, or the end shields have the same shape but can be installed on any side of the operating shaft. on one end face.

In an embodiment of the switching unit according to the invention which is not shown in detail, this is done in order to simplify production. Removable end shields are eliminated. In this case, although the tensioning device is arranged outside the position of the groove 2e, 22e where the contact rod is installed, it is still protected inside the operating shaft body.

Claims (9)

1. An operating shaft unit of a switch, which has an operating shaft body (2; 22) and a contact rod (3; 23) supported on the operating shaft body, and is characterized in that it is provided with a (2; 22) End shields (8; 28) on opposite sides, said end shields are used to rotatably install the operating shaft unit of the switch. 2. The operating shaft unit according to claim 1, characterized in that the contact lever (3; 23) can be arranged on the opposite side of the operating shaft body (2; 23) and covered with an end cap (8; 28). The tightening device (7; 2d) is loaded. 3. The actuating shaft unit according to claim 1 or 2, characterized in that the end shield (8; 28) is positively connected to the Opposite sides of the operating shaft body (2; 22) are connected. 4. The operating shaft unit according to claim 3, characterized in that the protrusions (8a, 8b) formed on the inner side of the end cover (8) and the cutouts (2a, 2b) provided on the opposite side of the operating shaft body (2) ) to engage. 5. The operating shaft unit according to claim 4, characterized in that one of the cutouts is formed by a through hole (2b) arranged in the operating shaft body (2), which is used to install an operating shaft unit Pin for operation (1). 6. The operating shaft unit according to claim 4 or 5, characterized in that the tensioning device (7, 2d) is installed through a radially extending grooved groove (2c) in the operating shaft body (2), and in Two further protrusions (8c) are provided on the inner side of the respective end shield (8). 7. The operating shaft unit according to claim 3, characterized in that some parts of the end cover (8) are made into cutouts (28a, 28b), and they are provided with the raised portion (22a) on the opposite side of the operating shaft body (22) , 22b) meshing with each other. 8. The operating shaft unit according to claim 7, characterized in that some cutouts in the disc-shaped end shield (28) are U-shaped cutouts, wherein the section (28c) bent from the bottom section of the U-shaped cutout ) and the corresponding slit-shaped groove (22f) of the operating shaft body (22) are engaged with each other. 9. The actuating shaft unit according to claim 7 or 8, characterized in that a radially extending groove-shaped recess (22c) in the actuating shaft body (22) is used for accommodating the tensioning device (26, 27).

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