1. Cable-stay bridge is with tensile type bridge support of big displacement volume, top-down include roof (2), well bedplate (5), spherical crown board (7) and bottom plate (10), and the bottom surface of well bedplate (5) is concave spherical surface, and the top surface of spherical crown board (7) is convex spherical surface, its characterized in that:

the centers of the middle seat plate (5) and the spherical crown plate (7) are provided with corresponding vertical through holes, and the upper aperture of the vertical through hole of the middle seat plate (5) is larger than the lower aperture;

the upper portion of the vertical through hole of the middle seat plate (5) is provided with an annular tensile spherical crown plate (6), the inner side of the top of the tensile spherical crown plate (6) is provided with a circular sinking groove, the tensile shaft (8) is inserted into the vertical through hole, and the expanded end at the top of the tensile shaft (8) is pressed in the sinking groove of the tensile spherical crown plate (6).

2. The large displacement tension type bridge support for a cable-stayed bridge according to claim 1, wherein:

the periphery of the top of the middle seat plate (5) is provided with two symmetrical transverse shear plates (3) and two symmetrical longitudinal limiting plates (4);

a groove is formed in the inner side of the top of the longitudinal limiting plate (4), a boss is arranged on the corresponding middle seat plate (5), and the boss of the middle seat plate (5) is embedded into the groove of the longitudinal limiting plate (4);

the transverse shear plate (3) is fixed to the bottom surface of the top plate (2) through a shear bolt (3 a), and the longitudinal limit plate (4) is fixed to the bottom surface of the top plate (2) through a longitudinal limit bolt (4 a).

3. The large displacement tension type bridge support for a cable-stayed bridge according to claim 2, wherein:

a sunken groove is formed in the top surface of the bottom plate (10), and the spherical crown plate (7) is positioned in the groove of the bottom plate (10);

two symmetrical transverse limiting plates (9) are arranged at the bottom of the middle seat plate (5) and the periphery of the top of the spherical crown plate (7), boss strips are arranged at the bottom of the inner sides of the transverse limiting plates (9), grooves are arranged at the outer sides of the corresponding spherical crown plates (7), the boss strips of the transverse limiting plates (9) are embedded into the grooves of the spherical crown plates (7), and the edge of the middle seat plate (5) is pressed on the boss strips of the transverse limiting plates (9);

the transverse limit plate (9) is fixed to the top surface of the bottom plate (10) through a transverse limit bolt (9 a).

4. The large displacement tension type bridge support for a cable-stayed bridge according to claim 3, wherein:

an upper slope adjusting plate (1) is arranged above the top plate (2), and the top plate (2) and the upper slope adjusting plate (1) are fixed through an upper bolt (13);

a lower adjusting plate (11) is arranged below the bottom plate (10), and the bottom plate (10) and the lower adjusting plate (11) are fixed through a lower bolt (12).

5. The large displacement tension type bridge support for a cable-stayed bridge according to claim 4, wherein:

the bottom of the top plate (2) is provided with a transverse thin plate (2 a), the top of the middle seat plate (5) is embedded with a transverse sliding plate (5 a), and the transverse thin plate (2 a) and the transverse sliding plate (5 a) form a pair of plane friction pairs.

6. The large displacement tension type bridge support for a cable-stayed bridge according to claim 5, wherein:

a vertical first thin plate (4 b) and a horizontal second thin plate (4 c) are arranged in the groove of the longitudinal limiting plate (4), and a transverse vertical SF plate (5 c) and a transverse flat SF plate (5 d) are arranged on the corresponding boss of the middle seat plate (5) to form two pairs of plane friction pairs;

lateral SF plates (5 e) are arranged on the outer side of the bottom of the middle seat plate (5), third thin plates (9 b) are arranged on the inner sides of the corresponding transverse limiting plates (9), and the lateral SF plates (5 e) and the third thin plates (9 b) form a pair of plane friction pairs.

7. The large displacement tension type bridge support for a cable-stayed bridge according to claim 6, wherein:

the bottom surface of the middle seat plate (5) is embedded with a rotating sliding plate (5 b) which forms a pair of spherical rotating friction pairs with the top surface of the spherical crown plate (7).

8. The large displacement tension type bridge support for a cable-stayed bridge according to claim 7, wherein:

an annular step is formed between the upper part and the lower part of the vertical through hole of the middle seat plate (5) and is a curved surface, and the bottom surface of the corresponding tensile spherical crown plate (6) is a curved surface;

the bottom surface of the tensile spherical crown plate (6) is embedded with a tensile rotary sliding plate (6 a), and the tensile rotary sliding plate (6 a) and the step curved surface form a pair of spherical tensile rotary friction pairs.

9. The large displacement tension type bridge support for a cable-stayed bridge according to claim 8, wherein:

the bottom surface of the spherical crown plate (7) is embedded with a longitudinal sliding plate (7 a), and the corresponding bottom plate (10) is also provided with the longitudinal sliding plate (7 a), and the longitudinal sliding plate and the bottom plate form a pair of plane friction pairs.

10. The large displacement tension type bridge support for a cable-stayed bridge according to claim 9, wherein:

a horizontal longitudinal flat SF plate (7 b) is arranged in a groove on the outer side of the spherical crown plate (7), a fourth thin plate (9 c) is arranged on the bottom surface of a boss strip of the corresponding transverse limiting plate (9), and the longitudinal flat SF plate (7 b) and the fourth thin plate (9 c) form a pair of plane friction pairs.

Background

When a bridge is built in an earthquake high-intensity area, bridge isolation and vibration isolation design needs to be considered, and particularly in areas across rivers, lakes, seas, valleys and the like, the design of a large-span cable-stayed bridge and a suspension bridge needs to consider the requirement of earthquake resistance and meet the requirement of structural displacement under strong wind load. The bridge bearing is used as a carrier for connecting the bridge pier and the bridge superstructure, has the functions of bearing vertical bearing capacity and horizontal bearing capacity and also bearing vertical drawing force, and has the functions of shock absorption and isolation under the earthquake working condition. At present, rubber damping supports, swing type shock absorption and isolation supports and elastic plastic steel shock absorption supports in the engineering field are widely applied in the bridge field of China, but for large-span cable-stayed bridges, the application of the bridge supports is limited, and the calculated parameters are different from those of conventional prefabricated and cast-in-place structural bridges, such as overlarge displacement, special corners, tensile functions, shearing devices and the like.

The existing bridge supports for the cable-stayed bridge are mainly of two types, one is a common spherical support structure without a tensile device, the spherical support is inverted, the center of a sphere faces the direction of a pier, the size of a bottom plate of the support is increased for matching the design calculation displacement of the bridge, and the design calculation displacement comprises the combination of conventional temperature telescopic displacement and earthquake displacement; according to the structure, the transverse movable displacement and the longitudinal movable displacement are placed in the same plane, the displacement release path is oblique, the limit structure of the fixed pier bridge support is easily cut off during reset, and the whole stress system of the bridge support fails; in addition, a longitudinal movable support provided with a limiting block is arranged, and after the limiting block is cut off, the transverse movable displacement and the longitudinal movable displacement are still in the same plane, so that the problems are inevitable.

The other type is a spherical support with a tensile device, and a spherical support body structure is also adopted, and the transverse movable displacement and the longitudinal movable displacement are separately designed, but the matching stress of the drawing assembly and the support inner core is complex, the structural defects can not set sufficient rotating clearance, and the clear path of each function can not be ensured under the composite stress working conditions of pressing, drawing, rotating, shearing and the like; the limiting component of the individual tension and compression support structure is cut by adopting an integral steel piece, so that the assembly is difficult, and the daily maintenance and replacement are difficult.

At present, a shear structure is added in a single tensile support structure, but a shear section is not arranged, so that the replacement is difficult, great difficulty is caused for the subsequent maintenance of the bridge, and the cost is greatly increased.

Disclosure of Invention

The invention aims to provide a large-displacement tensile type bridge support for a cable-stayed bridge, which is added with tensile components such as a drawing shaft and the like to realize the tensile function of the bridge, is provided with a limit stop to realize the separation of the transverse movable displacement and the longitudinal movable displacement of the bridge, can bear the vertical pressure and also realize the release of the longitudinal large-displacement under the condition of bearing the vertical pulling resistance, can release the transverse movable displacement through a shearing device under the earthquake working condition and is suitable for the large-displacement cable-stayed bridge with the tensile requirement.

The technical scheme adopted by the invention is as follows:

cable-stay bridge is with tensile type bridge support of big displacement volume, top-down include roof, well bedplate, spherical crown board and bottom plate, and the bottom surface of well bedplate is concave spherical surface, and the top surface of spherical crown board is convex spherical surface, its characterized in that:

the centers of the middle seat plate and the spherical crown plate are provided with corresponding vertical through holes, and the upper aperture of the vertical through hole of the middle seat plate is larger than the lower aperture;

the upper portion of the vertical through hole of the middle seat plate is provided with an annular tensile spherical crown plate, the inner side of the top of the tensile spherical crown plate is provided with a circular sinking groove, the tensile shaft is inserted into the vertical through hole, and the expanded end at the top of the tensile shaft is pressed and covered in the sinking groove of the tensile spherical crown plate.

The periphery of the top of the middle seat plate is provided with two symmetrical transverse shear plates and two symmetrical longitudinal limiting plates;

the inner side of the top of the longitudinal limit plate is provided with a groove, a boss is arranged on the corresponding middle seat plate, and the boss of the middle seat plate is embedded into the groove of the longitudinal limit plate;

the transverse shear plate is fixed to the bottom surface of the top plate through a shear bolt, and the longitudinal limiting plate is fixed to the bottom surface of the top plate through a longitudinal limiting bolt.

The top surface of the bottom plate is provided with a sunken groove, and the spherical crown plate is positioned in the groove of the bottom plate;

the bottom of the middle seat plate and the periphery of the top of the spherical crown plate are provided with two symmetrical transverse limiting plates, the bottoms of the inner sides of the transverse limiting plates are provided with boss strips, the outer sides of the corresponding spherical crown plates are provided with grooves, the boss strips of the transverse limiting plates are embedded into the grooves of the spherical crown plates, and the edges of the middle seat plate are pressed on the boss strips of the transverse limiting plates;

the transverse limiting plate is fixed to the top surface of the bottom plate through a transverse limiting bolt.

An upper slope adjusting plate is arranged above the top plate, and the top plate and the upper slope adjusting plate are fixed through an upper bolt;

a lower adjusting plate is arranged below the bottom plate, and the bottom plate and the lower adjusting plate are fixed through a lower bolt.

The bottom of the top plate is provided with a transverse thin plate, the top of the middle base plate is embedded with a transverse sliding plate, and the transverse thin plate and the transverse sliding plate form a pair of plane friction pairs.

A groove of the longitudinal limiting plate is internally provided with a vertical first thin plate and a horizontal second thin plate, and a boss of the corresponding middle seat plate is provided with a transverse vertical SF plate and a transverse flat SF plate to form two pairs of plane friction pairs;

the lateral SF plate is arranged on the outer side of the bottom of the middle seat plate, the third thin plate is arranged on the inner side of the corresponding transverse limiting plate, and the lateral SF plate and the third thin plate form a pair of plane friction pairs.

The bottom surface of the middle seat plate is embedded with a rotating sliding plate, and the rotating sliding plate and the top surface of the spherical crown plate form a pair of spherical rotating friction pairs.

An annular step is formed between the upper part and the lower part of the vertical through hole of the middle seat plate, the step is a curved surface, and the bottom surface of the corresponding tensile spherical crown plate is a curved surface;

the bottom surface of the tensile spherical crown plate is embedded with a tensile rotary sliding plate, and the tensile rotary sliding plate and the step curved surface form a pair of spherical surface tensile rotary friction pairs.

The bottom surface of the spherical crown plate is embedded with a longitudinal sliding plate, the corresponding bottom plate is also provided with a longitudinal sliding plate, and the longitudinal sliding plate form a pair of plane friction pairs.

A horizontal longitudinal flat SF plate is arranged in the groove on the outer side of the spherical crown plate, a fourth thin plate is arranged on the bottom surface of the boss strip of the corresponding transverse limiting plate, and the longitudinal flat SF plate and the fourth thin plate form a pair of plane friction pairs.

The invention has the following advantages:

1. the whole structure of the invention adopts the separation design of transverse movable displacement and longitudinal movable displacement, thereby avoiding the phenomenon of skew crossing when the bridge support is released or reset.

2. The drawing component and the limiting component of the integral structure are overlapped, so that the structure of the traditional tensile support is simplified, and the comprehensive cost is reduced.

3. According to the invention, through the structure that the grooves are arranged on the bottom plate, the longitudinal large displacement releases movable displacement in the grooves of the bottom plate in a single direction, and the path is clear; the horizontal limiting plate and the horizontal limiting bolt that set up have changed the whole cast form of traditional tensile support bottom plate, and it is convenient to change, and the equipment is easy.

4. The drawing shaft and the spherical crown plate are in threaded fit, and the threaded fit length with the corresponding length can be set according to the calculated drawing force; the drawing shaft is lower than the drawing spherical crown plate, so that the overall height of the support is indirectly reduced.

5. According to the invention, the upper part and the lower part of the support are respectively provided with the upper slope-adjusting steel plate and the lower flat plate, so that the flatness of the upper part and the lower part of the support is ensured, and the mounting precision of the support is improved.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Fig. 2 is a side view of the present invention.

Fig. 3 is a top view of the present invention.

Fig. 4 is an axial side quarter sectional view of the present invention.

Fig. 5 is a partial enlarged view of P in fig. 1.

Fig. 6 is a partial enlarged view of Q in fig. 1.

Fig. 7 is a partial enlarged view of M in fig. 1.

Fig. 8 is a partial enlarged view of N in fig. 2.

Fig. 9 is a schematic view of the lateral displacement of the present invention.

Fig. 10 is a schematic view of the longitudinal displacement of the present invention.

The labels in the figure are:

1-up-regulating slope board;

2-top plate, 2 a-transverse thin plate;

3-transverse shear plate, 3 a-shear bolt;

4-longitudinal limiting plate, 4 a-longitudinal limiting bolt, 4 b-first thin plate, and 4 c-second thin plate;

5-a middle seat plate, 5 a-a transverse sliding plate, 5 b-a rotary sliding plate, 5 c-a transverse vertical SF plate, 5 d-a transverse flat SF plate, and 5 e-a lateral SF plate;

6-tensile spherical crown plate, 6 a-tensile rotary sliding plate;

7-spherical crown plate, 7 a-longitudinal sliding plate, 7 b-longitudinal flat SF plate;

8-tensile shaft;

9-a transverse limiting plate, 9 a-a transverse limiting bolt, 9 b-a third thin plate, and 9 c-a fourth thin plate;

10-base plate, 10 a-longitudinal sheet;

11-Down-Regulation plate;

12-sleeve, 12 a-lower bolt, 12 b-anchor rod;

13-upper bolt, 13 a-spacer, 13 b-nut.

Detailed Description

The present invention will be described in detail with reference to specific embodiments.

The invention relates to a large-displacement tensile bridge support for a kilometer-grade cable-stayed bridge, which comprises a top plate 2, a middle seat plate 5, a spherical crown plate 7 and a bottom plate 10 from top to bottom, wherein the bottom surface of the middle seat plate 5 is a concave spherical surface, and the top surface of the spherical crown plate 7 is a convex spherical surface.

The centers of the middle seat plate 5 and the spherical crown plate 7 are provided with corresponding vertical through holes, and the upper aperture of the vertical through hole of the middle seat plate 5 is larger than the lower aperture; the upper portion of the vertical through hole of the middle seat plate 5 is provided with an annular tensile spherical crown plate 6, the inner side of the top of the tensile spherical crown plate 6 is provided with a sunken circular sinking groove, the tensile shaft 8 is inserted into the vertical through hole, and the expanded end at the top of the tensile shaft 8 is pressed in the sinking groove of the tensile spherical crown plate 6.

The periphery of the top of the middle seat plate 5 is provided with two symmetrical transverse shear plates 3 and two symmetrical longitudinal limiting plates 4; a groove is formed in the inner side of the top of the longitudinal limit plate 4, a boss is arranged on the corresponding middle seat plate 5, and the boss of the middle seat plate 5 is embedded into the groove of the longitudinal limit plate 4; the transverse shear plate 3 is fixed to the bottom surface of the top plate 2 by a shear bolt 3a, and the longitudinal limit plate 4 is fixed to the bottom surface of the top plate 2 by a longitudinal limit bolt 4 a.

The top surface of the bottom plate 10 is provided with a sunken groove, and the spherical crown plate 7 is positioned in the groove of the bottom plate 10; two symmetrical transverse limiting plates 9 are arranged at the bottom of the middle seat plate 5 and the periphery of the top of the spherical crown plate 7, boss strips are arranged at the bottoms of the inner sides of the transverse limiting plates 9, grooves are formed in the outer sides of the corresponding spherical crown plates 7, the boss strips of the transverse limiting plates 9 are inserted into the grooves of the spherical crown plates 7, and the edges of the middle seat plate 5 are pressed on the boss strips of the transverse limiting plates 9; the lateral stopper plate 9 is fixed to the top surface of the base plate 10 by a lateral stopper pin 9 a.

An upper slope adjusting plate 1 is arranged above the top plate 2, and the top plate 2 and the upper slope adjusting plate 1 are fixed through an upper bolt 13; a lower leveling plate 11 is arranged below the bottom plate 10, and the bottom plate 10 and the lower leveling plate 11 are fixed through a lower bolt 12.

The support structure of the invention is provided with a plurality of friction pairs, comprising:

1. the bottom of the top plate 2 is provided with a transverse thin plate 2a, the top of the middle seat plate 5 is embedded with a transverse sliding plate 5a, and the transverse thin plate 2a and the transverse sliding plate 5a form a pair of plane friction pairs.

2. Vertical first thin plates 4b and horizontal second thin plates 4c are arranged in grooves of the longitudinal limiting plates 4, and transverse vertical SF plates 5c and transverse flat SF plates 5d are arranged on bosses of the corresponding middle seat plates 5 to form two pairs of plane friction pairs.

3. The lateral SF plate 5e is arranged on the outer side of the bottom of the middle seat plate 5, the third thin plate 9b is arranged on the inner side of the corresponding transverse limiting plate 9, and the lateral SF plate 5e and the third thin plate 9b form a pair of plane friction pairs.

4. The bottom surface of the middle seat plate 5 is embedded with a rotating sliding plate 5b, and forms a pair of spherical rotating friction pairs with the top surface of the spherical crown plate 7.

5. An annular step is formed between the upper part and the lower part of the vertical through hole of the middle seat plate 5, the step is a curved surface, and the bottom surface of the corresponding tensile spherical crown plate 6 is a curved surface; the bottom surface of the tensile spherical crown plate 6 is embedded with a tensile rotary sliding plate 6a, and the tensile rotary sliding plate 6a and the step curved surface form a pair of spherical tensile rotary friction pairs.

6. The bottom surface of the spherical crown plate 7 is embedded with a longitudinal sliding plate 7a, the corresponding bottom plate 10 is also provided with the longitudinal sliding plate 7a, and the two form a pair of plane friction pairs.

7. A horizontal longitudinal flat SF plate 7b is arranged in a groove on the outer side of the spherical crown plate 7, a fourth thin plate 9c is arranged on the bottom surface of a boss bar of the corresponding transverse limiting plate 9, and the longitudinal flat SF plate 7b and the fourth thin plate 9c form a pair of plane friction pairs.

The structure of the invention is explained in further detail with reference to the accompanying drawings:

the whole top-down of support includes that upward slope board 1, roof 2, well bedplate 5, tensile spherical crown board 6, spherical crown board 7, draw axle 8, bottom plate 10, lower flat board 11 etc. and well bedplate 5 is provided with horizontal shear plate 3 and vertical limiting plate 4 all around, and bottom plate 10 both sides only set up horizontal limiting plate 9, and well bedplate 5 upper portion is the plane, and the lower part is the concave surface, and the centre has the vestibule of two different diameters. The upper part of the spherical crown plate 7 is a spherical surface, the lower part is a plane, and the middle part is a threaded cavity.

The top plate 2 is connected with the transverse shear plate 3 by a shear bolt 3a, and the shear bolt 3a has a replaceable structure and can be replaced by a shear pin or other shearing devices; the top plate 2 is connected with the longitudinal limit plate 4 through a longitudinal limit bolt 4a with a large safety coefficient. The lower part of the top plate 2 is welded with a transverse thin plate 2a, and the inner side of the longitudinal limiting plate 4 is welded with a first thin plate 4b and a second thin plate 4 c.

A transverse sliding plate 5a is embedded in the upper part of the middle seat plate 5 and forms a plane friction pair for realizing transverse movable displacement with a transverse thin plate 2a below the top plate 2, the friction coefficient is not more than 0.03, and the transverse thin plate 2a can adopt a silicone grease-free high-performance sliding plate; a rotary sliding plate 5b is embedded in the concave surface at the lower part of the middle seat plate 5 and forms a spherical rotary friction pair with the spherical surface at the upper part of the spherical crown plate 7, and the friction coefficient is not more than 0.03; the interior of the middle seat plate 5 is a cylindrical cavity with different diameters, a rotating gap is formed between the large-diameter cavity and the tensile spherical crown plate 6, between the small-diameter cavity and the drawing shaft 8, a spherical tensile rotating friction pair is formed by the small spherical diameter below the large-diameter cylindrical surface and the tensile rotating sliding plate 6a embedded in the concave surface at the lower part of the tensile spherical crown plate 6, the friction coefficient is not more than 0.03, and the spherical surface can be plated with chrome or welded with a spherical thin plate.

Draw axle 8 and tensile spherical crown board 6 and be tight fit, be screw-thread fit with the inboard cavity of spherical crown board 7, the screw thread is thick tooth screw thread, should set up reliable screw thread locking tensile screw in spherical crown board 7 inside when drawing the assembly of axle 8, draws the axle diameter and takes value according to actual calculated value, and the material grade is not less than 45 steel, and minimum diameter is not less than 30 mm.

The longitudinal sliding plate 7a embedded at the bottom of the spherical crown plate 7 and the longitudinal sliding plate 7a welded in the inner groove of the bottom plate 10 form a plane friction pair, the friction coefficient is not more than 0.03, and the longitudinal sliding plate 7a can adopt a high-performance sliding plate without silicone grease; the upper edges of the two sides of the spherical crown plate are welded or screwed with longitudinal horizontal SF plates, and form a plane friction pair with a fourth thin plate 9c welded on the lower edge of the transverse limiting plate 9, and the friction coefficient is not more than 0.05.

And a horizontal limiting plate 9 connected with the bottom plate 10 through a horizontal limiting bolt 9a, wherein a third thin plate 9b welded on the inner side of the horizontal limiting plate 9 and a lateral SF plate of the middle seat plate 5 form a plane friction pair, and a small vertical friction force can be provided when the bridge generates a vertical drawing force, and the friction coefficient is not more than 0.05.

The longitudinal thin plate 10a with four corners trimmed is welded on the groove on the inner side of the bottom plate 10, and forms a plane friction pair for realizing longitudinal movable displacement with the longitudinal sliding plate 7a embedded on the lower part of the spherical crown plate 7, and the friction coefficient is not more than 0.03. Due to the large displacement, the longitudinal thin plates 10a can be welded in a split manner, but the surface flatness should be consistent with the overall structure.

The upper slope adjusting plate 1 on the upper part of the top plate 2 can be provided with a corresponding slope according to the slope of the bottom of the beam and is welded with the beam body, and the height of the short edge is not lower than 10 cm; the sleeve 12 extends into the anchor hole of the downward-adjusting plate at the lower part of the bottom plate 10, and is connected with the bottom plate, the downward-adjusting plate and the sleeve through a lower bolt 12a, and the sleeve is in threaded connection with the anchor rod. The lower anchoring piece composed of the sleeve 12, the lower bolt 12a and the anchor rod 12b can be arranged according to the size of the longitudinal movement displacement, and the number of the lower anchoring pieces is not less than the number of the upper anchoring pieces composed of the upper bolt 13, the gasket 13a and the nut 13 b.

As shown in fig. 9, under the earthquake working condition, after the shear bolt 3a on the transverse shear plate 3 is sheared, the whole body composed of the beam body, the upper slope adjusting plate 1 and the top plate 2 is released by transverse movable displacement along the longitudinal limiting plate 4, and the support body is not separated.

As shown in fig. 10, under normal conditions, the transverse shear plate 3 is connected with the top plate 2 and the middle seat plate 5, the drawing shaft 8 is connected with the spherical crown plate 7 and the tensile spherical crown plate 6, which are limited, and the longitudinal movable displacement with large displacement is released along the transverse limiting plate 9, and under the vertical limiting action of the transverse limiting plate 9, the support body is not separated.

The invention is not limited to the examples, and any equivalent changes to the technical solution of the invention by a person skilled in the art after reading the description of the invention are covered by the claims of the invention.