Hydraulic System for Preventing Drift of Large Inertia Closed Rotary System of Engineering Vehicle Based on Large Flow Cartridge Valve, Usage Method and Engineering Vehicle

Abstract

An anti-drift hydraulic system, a usage method and an engineering vehicle for a large-inertia closed-circuit slewing system of an engineering vehicle based on large-flow cartridge valves, including a make-up oil pump. The make-up oil pump is connected to a variable slewing pump and a slewing motor through a make-up oil valve group. The swash plate of the variable slewing pump is connected to a displacement regulating valve group. High-pressure safety valve groups are connected in parallel at both ends of the variable slewing pump. The variable slewing pump is connected to the slewing motor through an anti-drift valve group. The slewing motor is connected to a flushing valve group. The oil outlet of the make-up oil pump is also connected to a safety valve. An electronic control unit is also included, and the electronic control unit is connected to the displacement regulating valve group and the anti-drift valve group. By utilizing the characteristics of cartridge valves, such as sensitive action, large flow capacity and good sealing performance, the invention installs an anti-drift valve group composed of cartridge valves and electromagnetic directional control valves between the oil circuits of the variable slewing pump and the slewing motor, realizes the prevention of the slewing drift of the engineering vehicle, improves the safety and operation smoothness during slewing, and is suitable for popularization and promotion.

Description

Technical Field

[0001] The present invention relates to the technical field of construction machinery, and specifically to an anti-drift hydraulic system for a large-inertia closed-loop slewing system of an engineering vehicle based on large-flow cartridge valves, a usage method, and an engineering vehicle. Background Art

[0002] Hydraulic systems are widely used in engineering vehicles, with excavators being the most representative. Large hydraulic excavators are widely used in various mechanized construction operation projects such as civil engineering, bridges, water conservancy and electric power projects, and mining due to their flexibility. The slewing device of a hydraulic excavator is a device that drives the upper body of the excavator to rotate. Due to the large overall machine mass and load, it has significant large-inertia load characteristics. There are obvious slewing drift problems in large hydraulic excavators, resulting in poor controllability experience, affecting the service life of hydraulic components and posing safety hazards. However, at present, the slewing deviation problem still exists significantly in large hydraulic excavators on the market, and there is no effective solution. Solving the slewing drift problem remains an important topic in the research of large hydraulic construction machinery. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the deficiencies of the above-mentioned prior art, and provide an anti-drift hydraulic system for a large-inertia closed-loop slewing system of an engineering vehicle based on large-flow cartridge valves, a usage method, and an engineering vehicle with a simple structure and good effect.

[0004] The present invention is realized as follows: An anti-drift hydraulic system for a large-inertia closed-loop slewing system of an engineering vehicle based on large-flow cartridge valves includes a make-up oil pump. The oil outlet of the make-up oil pump is respectively connected to a variable slewing pump and a slewing motor through a make-up oil valve group I and a make-up oil valve group II. The swash plate of the variable slewing pump is connected to a displacement regulating valve group. High-pressure safety valve groups are connected in parallel at both ends of the variable slewing pump. The variable slewing pump is connected to the slewing motor through an anti-drift valve group. The anti-drift valve group includes a cartridge valve, an electromagnetic directional valve, and a high-pressure safety valve; the slewing motor is connected to a flushing valve group; the oil outlet of the make-up oil pump is also connected to a safety valve. An electronic control unit is also included, and the electronic control unit is connected to the displacement regulating valve group and the anti-drift valve group.

[0005] Further, the make-up oil valve group I and the make-up oil valve group II include two one-way valves connected in parallel.

[0006] The displacement regulating valve group includes two groups of proportional valves and a switching valve arranged symmetrically. The proportional valve is arranged between the swash plate and the make-up oil pump, and the switching valve is arranged between the swash plate and the oil return tank.

[0007] The switching valve is a two-position two-way electromagnetic directional valve.

[0008] The electromagnetic directional valve is connected to the hydraulic control end of the cartridge valve. The electromagnetic directional valve is a two-position three-way electromagnetic directional valve. The high-pressure safety valve is connected between the slewing motor and the safety valve.

[0009] The flushing valve group includes a flushing valve, a throttle valve, and a pressure-holding valve. The flushing valve is connected to both ends of the slewing motor. The flushing valve is connected back to the oil tank through the throttle valve and the pressure-holding valve.

[0010] The flushing valve is a three-position three-way hydraulically controlled directional valve.

[0011] The use of a large-inertia closed-loop slewing system anti-drift hydraulic system for construction vehicles based on large-flow cartridge valves includes the use methods of slewing start and slewing stop.

[0012] Slewing start:

[0013] A1. The electronic control unit gives electrical signals for controlling the displacement regulating valve group and the anti-drift valve group according to the input instructions.

[0014] A2. The displacement regulating valve group adjusts the swash plate movement of the variable slewing pump, thereby controlling the operation direction and displacement of the variable slewing pump.

[0015] A3. The electromagnetic directional valve of the anti-drift valve group is energized, the cartridge valve opens, and the hydraulic oil drives the slewing motor to rotate from the variable slewing pump through the anti-drift valve group.

[0016] A4. The hydraulic oil on the low-pressure side of the slewing motor flows through the flushing valve group and then flows into the oil tank together with the case drain oil.

[0017] Slewing stop:

[0018] B1. The electronic control unit gives electrical signals for controlling the displacement regulating valve group and the anti-drift valve group according to the input instructions.

[0019] B2. The displacement regulating valve group adjusts the swash plate of the variable slewing pump to make the flow output of the variable slewing pump zero.

[0020] B3. The electromagnetic directional valve of the anti-drift valve group is de-energized, the cartridge valve closes to cut off the oil circuit, and the slewing motor stops rotating.

[0021] The hydraulic oil discharged in the closed circuit is replenished to the circuit by the make-up oil pump through the make-up oil valve group I and the make-up oil valve group II to prevent air suction.

[0022] A construction vehicle includes a large-inertia closed-loop slewing system anti-drift hydraulic system for construction vehicles based on large-flow cartridge valves and the use method of the large-inertia closed-loop slewing system anti-drift hydraulic system for construction vehicles based on large-flow cartridge valves.

[0023] The present invention has the following advantages: The anti-drift hydraulic system, usage method and engineering vehicle of the large-inertia closed-circuit slewing system of the engineering vehicle based on large-flow cartridge valves install an anti-drift valve group composed of cartridge valves, electromagnetic directional control valves and high-pressure safety valves between the variable slewing pump and the slewing motor oil circuits, preventing the slewing drift of the engineering vehicle and improving the safety and operation smoothness during slewing; adopting a closed-circuit slewing system, a hydraulic pump drives the hydraulic motor to move, avoiding problems such as inaccurate actuator movement, severe vibration during braking and hydraulic shock caused by air entering the system; the flushing valve group and the oil replenishing valve group eliminate the heat of the hydraulic oil circuit, extend the service life of components, and ensure the reliability of the system; the use of the safety valve effectively provides overload protection for the system, and the hydraulic system has good safety. Brief Description of the Drawings

[0024] Figure 1 is the hydraulic system diagram of the present invention;

[0025] Figure 2 is the structural schematic diagram of the displacement regulating valve group of the present invention;

[0026] Figure 3 is the structural schematic diagram of the anti-drift valve group of the present invention;

[0027] Figure 4 is the structural schematic diagram of the flushing valve group of the present invention.

[0028] In the figure: 1. Safety valve, 2. Oil replenishing valve group I, 3. Displacement regulating valve group, 4. Anti-drift valve group, 5. Slewing motor, 6. Flushing valve group, 7. Variable slewing pump, 8. High-pressure safety valve group, 9. Oil replenishing pump, 10. Oil replenishing valve group II, 3.1. Proportional valve, 3.2. Switch valve, 4.1. Cartridge valve, 4.2. Electromagnetic directional control valve, 4.3. High-pressure safety valve, 6.1. Flushing valve, 6.2. Throttle valve, 6.3. Pressure maintaining valve. Detailed Embodiments

[0029] The following is a description of the preferred embodiments of the present invention for patents in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention for patents and are not used to limit the present invention for patents.

[0030] As Figures 1 to 4The anti-drift hydraulic system of the large inertia closed-loop slewing system for engineering vehicles based on large-flow cartridge valves shown in the figure includes a make-up oil pump 9. The oil outlet of the make-up oil pump 9 is respectively connected to a variable slewing pump 7 and a slewing motor 5 through a make-up valve group I 2 and a make-up valve group II 10. The swash plate of the variable slewing pump 7 is connected to a displacement regulating valve group 3. High-pressure safety valve groups 8 are connected in parallel at both ends of the variable slewing pump 7. The variable slewing pump 7 is connected to the slewing motor 5 through an anti-drift valve group 4. The anti-drift valve group 4 includes a cartridge valve 4.1, an electromagnetic directional valve 4.2 and a high-pressure safety valve 4.3; the slewing motor 5 is connected to a flushing valve group 6; the oil outlet of the make-up oil pump 9 is also connected to a safety valve 1. It also includes an electronic control unit, and the electronic control unit is connected to the displacement regulating valve group 3 and the anti-drift valve group 4. The anti-drift hydraulic system of the large inertia closed-loop slewing system for engineering vehicles based on large-flow cartridge valves of the present invention includes a variable slewing pump, a slewing motor, a make-up oil pump, a safety valve, a make-up valve group I, a make-up valve group II, a displacement regulating valve group, an anti-drift valve group, a flushing valve group, a high-pressure safety valve group and an electronic control unit. Among them, the displacement regulating valve group is connected to the swash plate of the variable slewing pump. The electronic control unit outputs an electrical signal to control the on-off of each valve of the displacement regulating valve group, thereby adjusting the moving direction and moving distance of the swash plate. The movement of the swash plate drives the rotation of the variable slewing pump, realizing the adjustment of the rotation direction and flow rate of the variable slewing pump; the anti-drift valve group is connected between the variable slewing pump and the slewing motor. The electronic control unit outputs an electrical signal to control the on-off of the anti-drift valve group, thereby controlling the on-off between the variable slewing pump and the slewing motor, preventing the drift of the engineering vehicle during slewing; the flushing valve group is connected in parallel at both ends of the oil port of the slewing motor. The high-pressure end of the slewing motor controls the working position of the flushing valve group. The low-pressure end of the slewing motor flows into the fuel tank through the flushing valve group, taking away the heat of the hydraulic oil circuit; the high-pressure safety valve group is composed of two parallel safety valves and is connected to both ends of the oil port of the variable slewing pump for overflow protection of the variable slewing pump system; the oil inlet of the safety valve is communicated with the oil outlet of the make-up oil pump and the oil port of the variable slewing pump. The make-up valve group I is connected between the make-up oil pump and the oil port of the variable slewing pump and is connected to the safety valve. The make-up valve group II is connected between the make-up oil pump and the oil port of the slewing motor. The safety valve is used to protect the entire hydraulic system; in actual work, the hydraulic oil output by the variable slewing pump flows through the anti-drift valve group, and the hydraulic oil flows into the slewing motor after passing through the anti-drift valve group. The hydraulic oil output by the slewing motor then flows into the variable slewing pump through the anti-drift valve group, which can effectively prevent the slewing drift of the engineering vehicle and improve safety.

[0031] As Figure 1The anti-drift hydraulic system of the large inertia closed-loop slewing system for engineering vehicles based on large-flow cartridge valves as shown. The oil replenishing valve group I 2 and the oil replenishing valve group II 10 include two one-way valves arranged in parallel. The hydraulic oil discharged from the closed-loop circuit is replenished to the circuit by the oil replenishing pump 9 through the oil replenishing valve group I 2 and the oil replenishing valve group II 10 to prevent air suction. The oil replenishing valve group of the present invention consists of two one-way valves arranged in parallel, enabling the unidirectional flow of the oil input by the oil replenishing pump, that is, realizing the replenishment of the oil and ensuring the safety of the hydraulic circuit.

[0032] As Figure 1 and Figure 2 The anti-drift hydraulic system of the large inertia closed-loop slewing system for engineering vehicles based on large-flow cartridge valves as shown. The displacement regulating valve group 3 includes two sets of proportional valves 3.1 and switching valves 3.2 arranged symmetrically. The proportional valve 3.1 is arranged between the swash plate and the oil replenishing pump 9, and the switching valve 3.2 is arranged between the swash plate and the oil return tank. The switching valve 3.2 is a two-position two-way electromagnetic reversing valve. In the displacement regulating valve group of the present invention, the two sets of proportional valves and switching valves are arranged symmetrically, and the two sets are respectively connected to both ends of the swash plate. Taking the increase of the swash plate swing angle as an example, the hydraulic oil from the oil replenishing pump enters the displacement regulating valve group. The electronic control unit controls the right upper proportional valve to reduce or even close the oil port opening, and the right lower switching valve is de-energized and in the right position. The oil in the right chamber of the swash plate flows into the oil tank through the right lower switching valve. At the same time, the electronic control unit controls the left upper proportional valve to increase the oil port opening, and the left lower switching valve is energized and in the right position. The oil in the left chamber of the swash plate flowing into the oil tank is blocked. The hydraulic oil flows through the left upper proportional valve to the left chamber of the swash plate of the variable slewing pump. The left chamber of the swash plate of the variable slewing pump is filled with oil, and the right chamber returns oil, so the swash plate swing angle increases and the displacement of the variable slewing pump increases.

[0033] As Figure 1 and Figure 3 The anti-drift hydraulic system of the large inertia closed-loop slewing system for engineering vehicles based on large-flow cartridge valves as shown. The electromagnetic reversing valve 4.2 is connected to the hydraulic control end of the cartridge valve 4.1. The electromagnetic reversing valve 4.2 is a two-position three-way electromagnetic reversing valve. The high-pressure safety valve 4.3 is connected between the slewing motor 5 and the safety valve 1. In the present invention, the electromagnetic reversing valve is connected to the hydraulic control end of the cartridge valve. The electronic control unit controls the opening and closing of the cartridge valve by controlling the electromagnetic reversing valve. The high-pressure safety valve is connected between the oil port of the slewing motor and the safety valve, and plays a safety protection role for the hydraulic system of the slewing motor 5 when the cartridge valve is closed. The electromagnetic reversing valve is a two-position three-way electromagnetic reversing valve. When the electromagnetic reversing valve is energized, it works in the upper position, and the oil circuit can realize the outflow of the hydraulic oil from the hydraulic control chamber of the cartridge valve, and the cartridge valve opens. When the electromagnetic reversing valve is de-energized, it works in the lower position, and the one-way valve is integrated in the lower position oil circuit. The hydraulic oil conducts unidirectionally to the hydraulic control chamber of the cartridge valve, and the outflow of the hydraulic oil from the hydraulic control chamber of the cartridge valve is blocked, and the cartridge valve closes.

[0034] As Figure 1 and Figure 4The anti-drift hydraulic system of the large-inertia closed-loop slewing system for engineering vehicles based on large-flow cartridge valves shown in the figure. The flushing valve group 6 includes a flushing valve 6.1, a throttle valve 6.2, and a pressure-holding valve 6.3. The flushing valve 6.1 is connected to both ends of the slewing motor 5. The flushing valve 6.1 is connected back to the oil tank through the throttle valve 6.2 and the pressure-holding valve 6.3. The flushing valve 6.1 is a three-position three-way hydraulically controlled directional valve. The flushing valve group of the present invention is sequentially provided with a flushing valve, a throttle valve, and a pressure-holding valve. The flushing valve is a three-position three-way hydraulically controlled directional valve, which is connected to both ends of the slewing motor, and the working position of the flushing valve is switched by the oil controller of the slewing motor. The pressure-holding valve is a safety valve used to protect the hydraulic system. Specifically, taking the upper oil port of the slewing motor as the high-pressure side as an example, when the pressure at the upper side hydraulic control end of the flushing valve is high, it pushes the plunger of the flushing valve to move downward, and the flushing valve works in the upper position. At this time, the low-pressure side hydraulic oil of the slewing motor enters the flushing valve. The size of the throttle orifice of the throttle valve determines the flushing flow rate. The oil then flows into the oil tank together with the case drain through the pressure-holding valve, taking away the heat of the hydraulic oil circuit.

[0035] The use of an anti-drift hydraulic system for a large-inertia closed-loop slewing system of an engineering vehicle based on large-flow cartridge valves includes the use methods of slewing start and slewing stop. In the closed-loop hydraulic slewing system, when the engineering vehicle performs a slewing operation, the electronic control unit controls the displacement regulating valve group 3 to adjust the swashplate of the variable displacement slewing pump 7. The motor rotation direction is achieved by adjusting the swashplate of the variable displacement slewing pump 7 to pass through the zero position, and the displacement of the variable displacement slewing pump 7 is controlled by changing the swashplate swing angle. At the same time, the solenoid directional valve 4.2 of the anti-drift valve group 4 is energized, and the cartridge valve 4.1 is opened. The hydraulic oil drives the slewing motor 5 to rotate. The hydraulic oil on the low-pressure side of the slewing motor 5 flows through the flushing valve group 6 and flows into the oil tank together with the case drain. The hydraulic oil discharged from the closed loop is replenished to the loop by the make-up oil pump 9 through the make-up oil valve group 2 and the make-up oil valve group 2 to prevent air suction. The flushing valve group 6 and the make-up oil valve group 2 and the make-up oil valve group 2 remove the heat of the hydraulic oil circuit. The high-pressure safety valve group 8 is used for overflow protection of the variable displacement slewing pump 7 system, and the safety valve 1 is used to protect the entire hydraulic system. When stopping slewing, the electronic control unit controls the displacement regulating valve group 3 to adjust the swashplate of the variable displacement slewing pump 7 to make the flow output of the variable displacement slewing pump 7 zero. At the same time, the solenoid directional valve 4.2 of the anti-drift valve group 4 is de-energized, and the cartridge valve 4.1 is closed to cut off the oil circuit. The slewing motor 5 stops rotating. The high-pressure safety valve 4.3 of the anti-drift valve group 4 is used for overflow protection of the instantaneous high pressure of the hydraulic system of the slewing motor 5 caused by the large inertia of the vehicle. In the hydraulic system of the anti-drift valve group 4, when stopping rotation, the inertia of the upper slewing drives the slewing motor 5 to rotate forcedly, and the hydraulic oil is forced to flow in the whole loop, resulting in slewing drift. The anti-drift valve group 4 of the present application cuts off the oil circuit at both ends of the slewing motor 5, effectively preventing slewing drift when stopping.

[0036] An engineering vehicle, comprising the above-mentioned anti-drift hydraulic system for the large inertia closed-loop slewing system of the engineering vehicle based on large flow cartridge valves and the usage method of the anti-drift hydraulic system for the large inertia closed-loop slewing system of the engineering vehicle based on large flow cartridge valves.

[0037] In summary, the anti-drift hydraulic system for the large inertia closed-loop slewing system of the engineering vehicle based on large flow cartridge valves, the usage method, and the engineering vehicle of the present invention utilize the characteristics of the cartridge valve, such as sensitive action, large flow capacity, and good sealing performance. The anti-drift valve group composed of the cartridge valve and the electromagnetic directional valve is installed between the variable slewing pump and the slewing motor oil circuit, realizing the prevention of the slewing drift of the engineering vehicle, improving the safety and operation smoothness during slewing, and being suitable for popularization and promotion.

[0038] Finally, it should be noted that the above are only preferred examples of the present invention for patent, and are not used to limit the present invention for patent. Although the present invention for patent has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention for patent shall be included within the protection scope of the present invention for patent.

Claims

1. A hydraulic system for preventing drift in a large inertia closed-loop slewing system of an engineering vehicle based on a large flow cartridge valve, characterized in that: It includes a make-up oil pump (9). The oil outlet of the make-up oil pump (9) is respectively connected to a variable swashplate pump (7) and a swing motor (5) through a make-up oil valve group I (2) and a make-up oil valve group II (10). The swashplate of the variable swashplate pump (7) is connected to a displacement regulating valve group (3). High-pressure safety valve groups (8) are connected in parallel at both ends of the variable swashplate pump (7). The variable swashplate pump (7) is connected to the swing motor (5) through an anti-drift valve group (4). The anti-drift valve group (4) includes a cartridge valve (4.1), an electromagnetic directional control valve (4.2) and a high-pressure safety valve (4.3); the swing motor (5) is connected to a flushing valve group (6); the oil outlet of the make-up oil pump (9) is also connected to a safety valve (1). It also includes an electronic control unit, and the electronic control unit is connected to the displacement regulating valve group (3) and the anti-drift valve group (4).

2. The anti-drift hydraulic system for the large inertia closed swing system of engineering vehicles based on large flow cartridge valves as described in claim 1, characterized in that: The make-up oil valve group I (2) and the make-up oil valve group II (10) include two one-way valves arranged in parallel.

3. The anti-drift hydraulic system for the large-inertia closed-loop slewing system of an engineering vehicle based on a large-flow cartridge valve as claimed in claim 1, characterized in that: The displacement regulating valve group (3) includes two groups of proportional valves (3.1) and switching valves (3.2) arranged symmetrically. The proportional valves (3.1) are arranged between the swashplate and the make-up oil pump (9), and the switching valves (3.2) are arranged between the swashplate and the oil return tank.

4. The anti-drift hydraulic system for the large inertia closed swing system of an engineering vehicle based on a large flow cartridge valve according to claim 3, characterized in that: The switching valve (3.2) is a two-position two-way electromagnetic directional control valve.

5. The anti-drift hydraulic system for the large inertia closed swing system of an engineering vehicle based on a large flow cartridge valve according to claim 1, characterized in that: The electromagnetic directional control valve (4.2) is connected to the hydraulic control end of the cartridge valve (4.1). The electromagnetic directional control valve (4.2) is a two-position three-way electromagnetic directional control valve. The high-pressure safety valve (4.3) is connected between the swing motor (5) and the safety valve (1).

6. The anti-drift hydraulic system for the large inertia closed-loop slewing system of engineering vehicles based on large flow cartridge valves as claimed in claim 1, characterized in that: The flushing valve group (6) includes a flushing valve (6.1), a throttle valve (6.2) and a pressure maintaining valve (6.3). The flushing valve (6.1) is connected to both ends of the swing motor (5). The flushing valve (6.1) is connected to the oil return tank through the throttle valve (6.2) and the pressure maintaining valve (6.3).

7. The anti-drift hydraulic system for the large-inertia closed-circuit slewing system of an engineering vehicle based on a large-flow cartridge valve as claimed in claim 6, characterized in that: The flushing valve (6.1) is a three-position three-way hydraulically controlled directional control valve.

8. Use of a hydraulic system for preventing drift in a large inertia closed swing system of an engineering vehicle based on a large flow cartridge valve, characterized in that: It includes an operation method for swing start and swing stop. Swing start: A1. The electronic control unit gives electrical signals for controlling the displacement regulating valve group (3) and the anti-drift valve group (4) according to the input instructions; A2. The displacement regulating valve group (3) adjusts the action of the swashplate of the variable swashplate pump (7), and then controls the operation direction and displacement of the variable swashplate pump (7); A3. The electromagnetic directional control valve (4.2) of the anti-drift valve group (4) is energized, the cartridge valve (4.1) is opened, and the hydraulic oil drives the swing motor (5) to rotate from the variable swashplate pump (7) through the anti-drift valve group (4); A4. The hydraulic oil on the low-pressure side of the swing motor (5) flows through the flushing valve group (6) and then flows into the oil tank together with the housing drain oil; Swing stop: B1. The electronic control unit gives electrical signals for controlling the displacement regulating valve group (3) and the anti-drift valve group (4) according to the input instructions; B2. The displacement regulating valve group (3) adjusts the swashplate of the variable swashplate pump (7) to make the flow output of the variable swashplate pump (7) zero; B3. The electromagnetic directional control valve (4.2) of the anti-drift valve group (4) is de-energized, the cartridge valve (4.1) is closed to cut off the oil circuit, and the swing motor (5) stops rotating.

9. The usage method of the anti-drift hydraulic system for the large inertia closed swing system of engineering vehicles based on large flow cartridge valves according to claim 8, characterized in that: The hydraulic oil discharged in the closed circuit is replenished to the circuit and prevented from sucking air by the make-up oil pump (9) through the make-up oil valve group I (2) and the make-up oil valve group II (10).

10. An engineering vehicle, characterized in that: It includes the anti-drift hydraulic system for the large inertia closed swing system of engineering vehicles based on large flow cartridge valves described in any one of claims 1-7 and the usage method of the anti-drift hydraulic system for the large inertia closed swing system of engineering vehicles based on large flow cartridge valves described in any one of claims 8-9.

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