TWI611102B - Electrohydraulic unit - Google Patents

Abstract

An electro-hydraulic unit having a hydraulic pump (10) driven by an electric motor (106), a measuring unit (16) for determining an actual value of a rotational speed or a reciprocating number of the hydraulic pump (110), and an adjusting unit (102), wherein the electric motor (106) can be adjusted according to the actual value, wherein the measuring unit (116) belongs to the hydraulic pump (110). (figure 2)

Description

Electro-hydraulic unit

An electrohydraulic unit of the present invention is directed to the citation of claim 1 of the patent application.

The electro-hydraulic unit has an electric motor for driving a hydraulic pump for the purpose of supplying a hydraulic damper with hydraulic medium. This is generally necessary to prevent load changes or to be affected by interference values. Here, the hydraulic pump is coupled to one shaft of the electric motor.

The hydraulic fluid flow carried by the hydraulic pump can be adjusted by the number of revolutions or reciprocating (stroke) or reciprocating frequency depending on the configuration of the hydraulic pump. For hydraulic pumps that operate in a rotary mode, such as an axial piston pump, this is the speed of the drive shaft. For hydraulic pumps that work in mobile mode, such as moving or circulating hydraulic cylinders, the number of reciprocations of their pistons. The number of revolutions or reciprocations is caused by the speed of the electric motor. Electro-hydraulic units are often referred to as variable speed pump units (dvP). The pump unit with a particularly simple design has a "constant pump" (Konstantpumpe), so the hydraulic fluid flow is roughly adjusted by the speed of the hydraulic pump or the electric motor.

In order to make the hydraulic medium flow related to the rotational speed of the hydraulic pump can be adjusted via the motor as needed when the load changes or an error value occurs, the conventional electro-hydraulic unit has a measuring unit in a closed circuit device to measure the rotational speed of the electric motor, and has a The adjusting unit adjusts the rotational speed, and the rotational speed of the hydraulic pump can be inferred from the measured electric motor rotational speed, and the rotational speed is indirectly measured in this manner.

In a conventional electro-hydraulic unit, this measuring unit is placed on or in an electric motor.

The disadvantage is that the measuring unit is to be placed on or in the electric motor, and the technical cost of the device (especially the mask means) is high.

In view of this, it is an object of the present invention to enable the rotational speed of the hydraulic fluid flow to be measured at a relatively low cost.

This object is achieved by an electro-hydraulic unit of claim 1 or item 13.

Other advantageous features of the invention are found in items 2 to 12 of the scope of the patent application.

An electric hydraulic unit (especially for supplying an oil pressure consuming device to an oil pressure medium or a hydraulic medium) has an electric motor for driving a hydraulic pump. In addition, the current pressure unit has a measuring unit with which the actual value of the rotational speed or the number of reciprocating pulses of the hydraulic pump can be determined. The electric motor can be adjusted according to the actual value by means of an adjusting unit of the electro-hydraulic unit. According to the invention, the measuring unit is a hydraulic pump, so that the rotational speed is not measured on the electric motor in a conventional manner, but can be measured directly on the hydraulic pump.

Different from the conventional method, the measuring unit belongs to an electric motor, and belongs to the hydraulic pump according to the invention. The advantage is that the measuring unit is located far away from the electric field or the magnetic field of the electric motor, so the measuring unit is shielded to prevent interference. The cost of the field is low or even negligible. Therefore, the design of the electric motor is relatively simple, that is, there is no measuring unit, so that a favorable standard electric motor can be used. Therefore, the electro-hydraulic unit according to the invention is advantageous.

The electrohydraulic unit of the invention is therefore designed as a variable speed pump unit (dvP), wherein the adjustment of the hydraulic medium flow is mainly caused by the adjustment of the electric motor. According to the invention, the measuring unit belongs to the hydraulic pump, so that the time until the hydraulic pump is adjusted to remove the deviation of the hydraulic medium flow is shortened, so that the hydraulic medium accumulation of the hydraulic pump can be adjusted by a high power method.

For the hydraulic pump with rotary operation, the number of revolutions or reciprocating can be measured by the number of revolutions per unit time. For the hydraulic pump with shifting operation, the number of revolutions or reciprocating can be used for "reciprocation (stroke) per unit time). The number is measured. The adjustment of the electric motor utilizes a closed circuit in which the regulating unit compares the actual value of the rotational speed or the number of reciprocations with a nominal value.

In addition to the actual value of the rotational speed or the number of reciprocations, the adjusting device can also obtain other program values of the electrohydraulic unit or the supplied oil to the energy consumer - for example a final control element (Stellglied) or a hydraulic cylinder. The position, pressure, or a hydraulic medium flow, thereby determining the nominal value of the rotational speed or number of reciprocating pumps of the hydraulic pump. If this method is not used (or in addition to this method), the nominal value can also be preset by an operator via one of the operating interfaces of the adjustment unit.

In a preferred further feature, the assay unit has a magnetic field sensor and at least one segmentable magnetized signal generator. Such a rotational speed or reciprocating number can be preset using a "Hall effect", and it is particularly advantageous that with such a sensor, the rotational speed or the number of reciprocations can be measured in a contactless manner.

In a preferred further feature, the magnetic field sensor is disposed on or in the hydraulic pump in a manner that is securely attached to the housing. The distance to the measurement and the orientation of the measurement are maintained relative to the generator. If the sensor or generator It is particularly advantageous to provide at least one section of the housing in such a way that the relevant section of the measuring unit is to be measured, and the housing can be used to prevent interference with electric or magnetic fields (for example of electric motors).

Preferably, the signal generator has a section that is not magnetizable or a recess. Thus, when the generator moves relative to the sensor, a magnetic field of the assay unit changes at least once.

In a preferred further feature, the signal generator is designed in the form of a gear and is coupled to a rotating portion of the hydraulic pump. The speed can thus be determined via the sensor. Here, the manner of rotating the portion is related to the manner in which the pump is constructed, for example, a shaft, a cylinder drum, an impeller or an internal gear or an external gear or a member connected thereto.

In a preferred further feature of the change, the signal generator is designed in the form of a gear strip and is connected to a substantially linearly moving portion of the hydraulic pump. Therefore, the number of reciprocations can be measured using a sensor. The manner in which the linearly moving component is dependent on the configuration of the pump can be, for example, a piston or a piston rod or a portion connected thereto.

Preferably, the gear or rack has a modulus greater than 0.3.俾 can have sufficient measurement accuracy.

In a further feature of a particularly simple design, the signal generator is designed in the form of a stamped metal sheet and can therefore be advantageously manufactured.

According to a particularly good and inexpensive feature, the measuring unit has a DSM speed sensor. It is the applicant's DSM speed sensor, which is especially suitable for use inside the hydraulic pump due to its strength and protection. Another advantage is that the sensor can be used to determine the manner of rotation or reciprocation and the state of rest.

In a preferred further feature, the adjustment unit can be utilized to adjust the electrical motor speed.

The hydraulic pump is further designed as a constant pump in a particularly simple and inexpensive manner. Therefore, the hydraulic medium flow of the hydraulic pump can be adjusted by the rotational speed of the electric motor and the hydraulic pump. For such electro-hydraulic units, it is particularly advantageous to measure the rotational speed of a hydraulic pump in accordance with the present invention. If the hydraulic pump is coupled to the electric motor via a coupler. Then, the rotational speed of the electric motor can be reduced or increased.

The invention also relates to an electro-hydraulic unit having

a hydraulic pump driven by an electric motor, and

a measuring unit having a Hall sensor having a signal generator, wherein the measuring unit is capable of determining an actual value of the number of revolutions of the hydraulic pump, and

An adjustment unit for adjusting a rotational speed of the electric motor according to the actual value and a nominal value, wherein the signal generator and the Hall sensor are disposed on a portion of the hydraulic pump.

An embodiment of a prior art and an electro-hydraulic unit is described in detail below using two schematic diagrams.

Figure 1 shows a conventional electro-hydraulic unit (1) having an assay unit (16) in a housing (18) of an electric motor (6).

The electro-hydraulic unit (1) has a driver adjustment device (2) which is connected to the electric motor (6) via a signal line (4). The electric motor (6) is coupled to a hydraulic pump (10) via a shaft (8). The hydraulic pump (10) is connected to a signal line (12); it can be used to draw oil pressure medium at low pressure, and the hydraulic pump (10) is connected to a pressure line (14), which can be used to pressurize the medium. It is sent to a hydraulic consumer (not shown) against a load or a load of pressure.

The electric motor (6) can measure the rotational speed of the electric motor (6) by means of the measuring unit (16). Here, the measuring unit (16) is provided in the casing (18) of the electric motor (6), and it is costly to shield the electric field and the magnetic field of the electric motor (6).

In order to form a "closed circuit" or regulating circuit, the measuring unit (16) is connected to the driver adjusting device (2) by means of a signal line (20). The measured rotational speed is sent to the actuator adjustment device (2) via the signal line (20). The actual value is compared with the nominal speed value in the drive adjustment device (2) and an adjustment value is determined using the adjustment parameter to match the drive power of the electric motor (6).

2 shows an electro-hydraulic unit (101) of the present invention having an assay unit (116) disposed in a housing (118) of a constant axial piston pump (110).

The electro-hydraulic unit (101) has a driver adjustment device (102) coupled to a non-synchronous electric motor (106) via a signal line (104) that is non-rotatable and constant via a drive shaft (108) The axial piston pump (110) is coupled and the constant axial pump (110) is coupled to a suction line (112) through which the oil pressure medium can be drawn at low pressure. In addition, the constant axial piston pump (110) is coupled to a pressure line (114) through which the hydraulic medium can be delivered to a hydraulic consumer (not shown) against a load or a load of pressure.

The measuring unit (116) is disposed in the housing (118) of the constant axial piston pump (110) which operates in accordance with the "Hall effect". It has a Hall signal generator (116a) and a Hall sensor (116). The Hall sensor is designed in the form of the applicant's Series 10 DSM speed sensor.

The Hall signal generator (116a) is designed as a ferromagnetic gear with forty-eight teeth and a modulus of one, which is stamped from a 6 mm thick piece of metal. The Hall sensor (116b) is protected by IP69K, so it is protected from dust, wire intrusion and water under high pressure. Its temperature resistance is in the temperature range of 40 ° C ~ 150 ° C, Hall sense. The detector (116b) is fixed to the housing (118) of the constant axial piston pump (110) in a simple manner via a wafer (not shown) and is set to sense Hall with respect to the Hall signal generator (116a). A longitudinal axis of the detector (116b) is arranged to be disposed along a normal line (with a deviation of at most 2°) on a cylindrical surface (which intersects a portion of the circle of the gear).

The measuring unit (116), which is designed in the form of a DSM speed sensor, has the following self-diagnostic function: the stationary state detection, the detection Hall sensor (116b) is incorrectly set with respect to the Hall signal generator (116a).

Other operational parameters related to the function of the assay unit (116) [particularly regarding the setting of the Hall sensor (116b) relative Hall signal generator (116a)] can be found in the applicant's information booklet RD 95132.

The rotational speed of the constant axial piston pump (110) can be determined by the measuring unit (116). Here, the measuring unit (116) is shielded against the electromagnetic field of the electric motor by means of a housing (118) of a constant axial piston pump (110).

The measuring unit (116) is coupled to the actuator adjusting device (102) via a signal line (120) to deliver the actual value of the measured rotational speed of the constant axial piston pump (110) to the actuator adjusting device (102). The actual value is compared with a nominal speed value in the actuator adjustment device (102), and an adjustment value is obtained using the "adjustment parameter" to match the drive power of the asynchronous electric motor (106).

bergeordnet)的調節單元(圖未示)依電液壓單元或油壓耗能器(圖未示)的程序及/或操作參數而定經一信號電路傳送。Here, the nominal value can be sent to the adjustment unit (102) via an operator's interface (not shown) via a signal line (122), and/or by a side position (nebengeordnet) or upper position (

The adjustment unit (not shown) of the bergeordnet) is transmitted via a signal circuit according to the program and/or operating parameters of the electrohydraulic unit or the hydraulic consuming device (not shown).

The design of the hydraulic pump of the electro-hydraulic unit is not limited to the illustrated constant axial piston pump (110) of the swash plate configuration. It can also be designed as a rotary hydraulic pump, such as an external gear or internal gear type, a ring gear type, a screw type, a liquid chamber or a radial piston pump, or a hydraulic cylinder that is moved or recirculating.

The hydraulic pump can be designed in an adjustable or constant manner.

In summary, the present invention is an electro-hydraulic unit having

a hydraulic pump (10) driven by an electric motor (106)

a measuring unit (16) by which the actual value of the number of revolutions or reciprocating of the hydraulic pump (110) can be determined, and

An adjustment unit (102) by which the electric motor (106) can be adjusted according to the actual value, characterized in that the measuring unit (116) belongs to the hydraulic pump (110).

(1). . . Electro-hydraulic unit

(2). . . Drive adjustment device

(4). . . Signal line

(6). . . Electric motor

(8). . . axis

(10). . . Hydraulic pump

(12). . . Suction line

(16). . . Measuring unit

(18). . . case

(20). . . Signal pipeline

(101). . . Electro-hydraulic unit

(102). . . Drive adjustment device

(104). . . Signal line

(106). . . Non-synchronous electric motor

(108). . . Drive shaft

(110). . . Constant axial piston pump

(112). . . Suction line

(116). . . Measuring unit

(116a). . . Hall signal generator

(116b). . . Hall sensor

(118). . . case

(120). . . Signal line

(122). . . Signal line

(124). . . Signal line

Figure 1 is a conventional electro-hydraulic unit (1) having an assay unit (16) in an electric motor (6) housing (18);

Figure 2 is an electro-hydraulic unit (101) of the present invention having an assay unit (16) in a hydraulic pump housing (18).

(101)‧‧‧Electric hydraulic unit

(102)‧‧‧Drive adjustment device

(104)‧‧‧Signal lines

(106)‧‧‧ Non-synchronous electric motor

(110)‧‧‧Constant axial piston pump

(112) ‧‧‧ suction line

(114)‧‧‧ Pressure lines

(116)‧‧‧Measurement unit

(116a)‧‧‧ Hall Signal Generator

(116b)‧‧‧ Hall sensor

(118)‧‧‧Shell

(120)‧‧‧Signal lines

(122)‧‧‧Signal lines

(124)‧‧‧Signal lines

Claims (11)

An electro-hydraulic unit having a hydraulic pump (10) driven by an electric motor (106), a measuring unit (16) for determining an actual value of the rotational speed of the hydraulic pump (110), and an adjusting unit (102) The electric motor (106) can be adjusted according to the actual value, wherein: the measuring unit (116) is provided on the hydraulic pump (110), wherein the electric unit can be adjusted via the adjusting unit (102) The rotation speed of the motor (106), the measuring unit (116) has a magnetic field sensor (116b) and at least one segmentable magnetized signal generator (116a), the magnetic field sensor (116b) is firmly fixed at The manner of the housing is provided on or in the hydraulic pump (110). An electro-hydraulic unit of claim 1, wherein the signal generator (116a) has a non-magnetizable section or a recess. An electro-hydraulic unit of claim 1, wherein the signal generator (116a) is designed in the form of a gear and is coupled to a rotating portion (108) of the hydraulic pump (110). An electro-hydraulic unit according to claim 1, wherein the signal generator (116a) is designed in the form of a gear bar and is connected to a substantially linearly moving portion of the hydraulic pump (110). An electro-hydraulic unit of claim 3 or 4, wherein the gear or rack has a modulus greater than 0.3. An electro-hydraulic unit of claim 1, wherein the signal generator (116a) is designed in the form of a stamped metal sheet. The electro-hydraulic unit of claim 1, wherein the measuring unit (116) has a DSM rotational speed sensor (116b). The electro-hydraulic unit of claim 1, wherein the adjusting unit (102) can adjust the rotational speed of the electric motor (106). The electro-hydraulic unit of claim 1, wherein the hydraulic pump (110) is a constant pump. An electro-hydraulic unit of claim 1, wherein the hydraulic pump (110) is coupled to the electric motor (106) via a coupler. An electro-hydraulic unit having a hydraulic pump (110) driven by an electric motor and a measuring unit (116) having a Hall sensor having a signal generator (116a), wherein the measuring unit is utilized ( 116) an actual value of the number of revolutions of the hydraulic pump (110), and an adjustment unit for adjusting a rotational speed of the electric motor (106) according to the actual value and a nominal value, wherein The signal generator (116a) and the Hall sensor (116b) are disposed on a portion of the hydraulic pump (110).